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Background: Data on antifungal prescribing in neonatal patients are limited to either single-center or single-country studies or to 1-day recording. Therefore, we assessed antifungal longitudinal usage in neonatal units (NUs) within Europe., Methods: CALYPSO, a prospective weekly point prevalence study on antifungal drug usage in NUs in 18 hospitals (8 European countries), was conducted in 2020 during a 12-week period. All patients receiving systemic antifungals were included. Ward demographics were collected at the beginning; ward and patient data including indication, risk factors and antifungal regimen were weekly collected prospectively., Results: Among 27 participating NUs, 15 (56%) practiced antifungal prophylaxis for neonates with birth weight <1000 g or <1500 g and additional risk factors. In total, 174 patients received antifungals with a median frequency per week of 10.5% ranging from 6.9% to 12.6%. Indication for antifungal prescribing was prophylaxis in 135/174 (78%) courses and treatment in 22% [39 courses (69% empirical, 10% preemptive, 21% targeted)]. Fluconazole was the most frequent systemic agent used both for prophylaxis (133/135) and treatment (15/39, 39%). Among neonates receiving prophylaxis, the most common risk factors were prematurity (119/135, 88%), mechanical ventilation (109/135, 81%) and central vascular catheters (89/135, 66%). However, gestational age <28 weeks was only recorded in 55/135 (41%) courses and birth weight <1000 g in 48/135 (35%). Most common reason for empirical treatment was late-onset sepsis; all 8 targeted courses were prescribed for invasive candidiasis., Conclusion: Antifungal usage in European NUs is driven by prophylaxis and empirical treatment with fluconazole being the most prescribed agent for both indications., Competing Interests: E.C.: Speaker at sponsored symposia for Pfizer and F2G. C.G. is funded by the Spanish Ministry of Science and Innovation—Instituto de Salud Carlos III and Fondos FEDER (Contrato Juan Rodés JR22/00044). A.H.G. has received grants from Gilead, Merck, Sharp & Dohme and Pfizer and has served as a consultant to Amplyx, Astellas, Basilea, F2G, Gilead. Merck, Sharp & Dohme, Pfizer, Scynexis and Mundipharma. T.L. has received a grant from Gilead Sciences, has served as a consultant to Gilead Sciences, Merck/MSD, Pfizer, Astellas, AstraZeneca, Recordati and Roche and served at the speaker´s bureau of Gilead Sciences, Merck/MSD, Astellas, Pfizer and GSK and Recordati. E.R. has received research grants from Merck, Abvie, Shionogi, Cidara and Pfizer Inc. to his institution and is a scientific advisor and member of the speaker bureaux for Gilead, Merck, Shionogi, Mundipharma and Pfizer Inc. For the remaining authors, there are no conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Aim: The aim of this review was to summarise the current knowledge on host-related factors that contribute to the development and severity of staphylococcal scalded skin syndrome (SSSS) in children., Methods: A comprehensive assessment and analysis of the existing literature on SSSS clinical features, pathogenesis and susceptibility factors., Results: SSSS is a blistering skin disease caused by circulating exfoliative toxins (ETs) of Staphylococcus aureus (S. aureus), almost exclusively affecting infants, young children and immunocompromised individuals. ETs possess serine protease activity and target desmoglein-1 (Dsg-1) in the superficial epidermis. While the role of S. aureus ETs and site of action are well-described, other host factors such as impaired immune responses to ETs, poor renal clearance and genetic factors are crucial for the onset of and/or the severity of SSSS in children., Conclusion: The fate of desmosomal fractions after cleavage by ETs, as well as the role of dermal inflammatory cell infiltrates remain to be elucidated., (© 2024 The Author(s). Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)

The Omicron variant is associated with increased transmissibility, but evidence about the impact of Omicron in seropositivity of children is limited. This study aims to evaluate SARS-CoV-2 seroprevalence in children during the different variants' subperiods. A prospective multicenter seroprevalence study was conducted in 7 University public hospitals in Greece from November 2021 to August 2022 (3 subperiods: November 2021-February 2022, March 2022-May 2022, June 2022-August 2022). Children from different age groups, admitted to the hospital or examined in outpatient clinics for reasons other than COVID-19 were enrolled. Neutralizing antibodies (Nabs), anti-Spike (anti-S) and anti-nucleocapsid (anti-N) SARS-CoV-2 IgG in serum were evaluated. A total of 2127 children (males:57,2%; median age:4,8years) were enrolled. Anti-N IgG seropositivity increased from 17,8% in the first sub-period to 40,7% in the second sub-period and then decreased in the third sub-period (36,7%). Anti-S IgG seropositivity appeared to have an increasing trend over the study period, starting from 34,8% and reaching 80,7%. Children aged 1-4 years old have significantly higher anti-N IgG titers compared to children aged 0-1 years old (p < 0,001). Infants have significantly lower anti-S IgG titers compared to all other age groups (p < 0,001). Immunocompromised children and infants have the lowest seropositivity for NAbs.Conclusions During the Omicron period, seropositivity significantly increased, as a result of higher transmissibility. Neonates and infants have lower antibody titers compared to other age groups, while young children aged 1-4 years old present higher antibody titers, suggesting that this age group may mount a higher antibody response. Continuous surveillance seroprevalence studies are needed in children, in order to identify the true extent of SARS-CoV-2 and guide the planning of adequate public health measures., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: COVID-19 vaccination has been recommended for children to protect them and to enable in-person educational and social activities., Methods: We estimated COVID-19 vaccination effectiveness (VE) against school absenteeism in children 5-17 years old hospitalized from September 1, 2021 through May 31, 2023. Full vaccination was defined as two vaccine doses., Results: We studied 231 children admitted to hospital with COVID-19, including 206 (89.2 %) unvaccinated/partially vaccinated and 25 (10.8 %) fully vaccinated. Unvaccinated/partially vaccinated children were absent from school for longer periods compared to fully vaccinated children (median absence: 14 versus 10 days; p-value = 0.05). Multivariable regression showed that full COVID-19 vaccination was associated with fewer days of absence compared to no/partial vaccination on average (adjusted relative risk: 0.77; 95 % CI: 0.61 to 0.98). COVID-19 VE was 50.7 % (95 % CI: -11.3 % to 78.2 %) for school absenteeism above the median duration of absenteeism., Conclusions: Full COVID-19 vaccination conferred protection against school absenteeism in hospitalized school-aged children with COVID-19., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: The CDC and ACIP recommend COVID-19 vaccination for patients with inborn errors of immunity (IEI). Not much is known about vaccine safety in IEI, and whether vaccination attenuates infection severity in IEI., Objective: To estimate COVID-19 vaccination safety and examine effect on outcomes in patients with IEI., Methods: We built a secure registry database in conjunction with the US Immunodeficiency Network to examine vaccination frequency and indicators of safety and effectiveness in IEI patients. The registry opened on January 1, 2022, and closed on August 19, 2022., Results: Physicians entered data on 1245 patients from 24 countries. The most common diagnoses were antibody deficiencies (63.7%). At least one COVID-19 vaccine was administered to 806 patients (64.7%), and 216 patients received vaccination prior to the development of COVID-19. The most common vaccines administered were mRNA-based (84.0%). Seventeen patients were reported to seek outpatient clinic or emergency room care for a vaccine-related complication, and one patient was hospitalized for symptomatic anemia. Eight hundred twenty-three patients (66.1%) experienced COVID-19 infection. Of these, 156 patients required hospitalization (19.0%), 47 required ICU care (5.7%), and 28 died (3.4%). Rates of hospitalization (9.3% versus 24.4%, p < 0.001), ICU admission (2.8% versus 7.6%, p = 0.013), and death (2.3% versus 4.3%, p = 0.202) in patients who had COVID-19 were lower in patients who received vaccination prior to infection. In adjusted logistic regression analysis, not having at least one COVID-19 vaccine significantly increased the odds of hospitalization and ICU admission., Conclusion: Vaccination for COVID-19 in the IEI population appears safe and attenuates COVID-19 severity., (© 2024. The Author(s).)

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe hyperinflammatory condition that may occur following SARS-CoV-2 infection. This retrospective, descriptive study of children hospitalized with multisystem inflammatory syndrome in children (MIS-C) in 12 tertiary care centers from 3/11/2020 to 12/31/2021. Demographics, clinical and laboratory characteristics, treatment and outcomes are described. Among 145 patients (95 males, median age 8.2 years) included, 123 met the WHO criteria for MIS-C, while 112 (77%) had serological evidence of SARS-CoV-2 infection. Fever was present in 99%, gastrointestinal symptoms in 77%, mucocutaneous involvement in 68% and respiratory symptoms in 28%. Fifty-five patients (38%) developed myocarditis, 29 (20%) pericarditis and 19 (13%) coronary aneurysms. Among the above cases 11/55 (20%), 1/29 (3.4%) and 5/19 (26.3%), respectively, cardiac complications had not fully resolved at discharge. Underlying comorbidities were reported in 18%. Median CRP value was 155 mg/l, ferritin 535 ng/ml, PCT 1.6 ng/ml and WBC 14.2 × 10 9 /mm 3 . Most patients had elevated troponin (41.3%) and/or NT-pro-BNP (49.6%). Intravenous immunoglobulin plus corticosteroids were used in 117/145 (80.6%), monotherapy with IVIG alone in 13/145 (8.9%) and with corticosteroids alone in 2/145 (1.3%). Anti-IL1 treatment was added in 15 patients (10.3%). Thirty-three patients (23%) were admitted to the PICU, 14% developed shock and 1 required ECMO. Mortality rate was 0.68%. The incidence of MIS-C was estimated at 0.69/1000 SARS-CoV-2 infections. Patients who presented with shock had higher levels of NT-pro-BNP compared to those who did not (p < 0.001). Acute kidney injury and/or myocarditis were associated with higher risk of developing shock., Conclusion: MIS-C is a novel, infrequent but serious disease entity. Cardiac manifestations included myocarditis and pericarditis, which resolved in most patients before discharge. Timely initiation of immunomodulatory therapy was shown to be effective. NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. Further research is required to elucidate the pathogenesis, risk factors and optimal management, and long-term outcomes of this clinical entity., What Is Known: • MIS-C is an infrequent but serious disease entity. • Patients with MIS-C present with multi-organ dysfunction, primarily involving the gastrointestinal and cardiovascular systems., What Is New: • NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. • Acute kidney injury and/or myocarditis were associated with higher risk of developing shock., (© 2024. The Author(s).)

Repeated implantation failure (RIF) is a significant limiting factor in assisted reproduction. Chronic endometrial inflammation has been noted in RIF women, therefore we sought to investigate the potential association of endometrial Th17/Treg ratio and endometrial inflammation in these cases. Endometrial pipelle biopsies were obtained from volunteers, 29 women with RIF (failure to achieve pregnancy following at least 3 transfers of high-grade embryos in IVF-cycles) and 27 fertile women (at least one child) in total, at the secretory phase of the menstrual cycle. Using tissues from 17 fertile and 18 RIF endometrial samples, stromal and immune cells were isolated and flow cytometry analysis was performed to determine Th17 and CD4+ CD25 high FOXP3 + cell populations in endometrial stromal cell suspensions. Another group of tissues from 10 fertile and 11 RIF samples were used for mRNA expression levels of Treg and Th17-cell transcription factors, FOXP3 and RORγt respectively. Endometrial inflammatory mediators' mRNA expression was also analyzed. A statistically significant increase in protein flow cytometry analysis of Th17/Treg ratio (p ≤ 0.05) as well as a reduction in absolute Treg cells in the endometrium (p ≤ 0.05) was noted in women with RIF. Additionally, RNA analysis on the same set of women indicated RORγt/FOXP3 significantly increased in women with RIF compared to fertile ones (p ≤ 0.05). Finally, women with RIF exhibited significantly (p ≤ 0.05) elevated mRNA levels of pro-inflammatory mediators (ΤΝF-a, ΙL-6, IL-8 and CCl2). Women with RIF exhibit elevated Th17/Treg ratio, mostly due to endometrial Treg depletion, as well as a pro-inflammatory state in the endometrium., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The limited reserves of neutrophils are implicated in the susceptibility to infection in neonates, however the regulation of neutrophil kinetics in infections in early life remains poorly understood. Here we show that the developmental endothelial locus (DEL-1) is elevated in neonates and is critical for survival from neonatal polymicrobial sepsis, by supporting emergency granulopoiesis. Septic DEL-1 deficient neonate mice display low numbers of myeloid-biased multipotent and granulocyte-macrophage progenitors in the bone marrow, resulting in neutropenia, exaggerated bacteremia, and increased mortality; defects that are rescued by DEL-1 administration. A high IL-10/IL-17A ratio, observed in newborn sepsis, sustains tissue DEL-1 expression, as IL-10 upregulates while IL-17 downregulates DEL-1. Consistently, serum DEL-1 and blood neutrophils are elevated in septic adult and neonate patients with high serum IL-10/IL-17A ratio, and mortality is lower in septic patients with high serum DEL-1. Therefore, IL-10/DEL-1 axis supports emergency granulopoiesis, prevents neutropenia and promotes sepsis survival in early life., (© 2024. The Author(s).)

In this nationwide retrospective study, a substantial decline in the incidence of multisystem inflammatory syndrome in children over 3 successive pandemic waves characterized by different severe acute respiratory syndrome coronavirus 2 variants was documented-from 3.4 of 1000 to 1.1 of 1000 and finally to 0.25 of 1000 confirmed severe acute respiratory syndrome coronavirus 2 positive cases (P < 0.0001), respectively, whereas clinical findings and severity did not significantly vary., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

School closures were enforced as measures to restrain the COVID-19 pandemic, based on the assumption that young children may play a key role in SARS-CoV-2 spread. This study aims to determine the prevalence of SARS-CoV-2 IgG antibodies in children and corresponding parents, in order to improve surveillance and estimate the prevalence of asymptomatic or subclinical COVID-19 cases. A prospective multicenter study was conducted between March and June 2021 in Greece. Children admitted to the hospital or examined in outpatient clinics for reasons other than COVID-19 and their parents were tested for anti-Spike SARS-CoV-2 IgG in serum. A questionnaire about clinical and demographic data was completed. The study included 823 participants: 427 children and 396 corresponding parents. The overall seroprevalence was 16.4% in parents and 13.8% in children. Among families with ≥ 1 seropositive child or parent, the combination of a seropositive parent and a corresponding seronegative child was 29.6%, a seronegative parent and a corresponding seropositive child was 24.7%, and a seropositive child with a corresponding seropositive parent was 45.7%. Age, level of education, and school or work attendance were not significantly associated with increased seropositivity. On the contrary, ethnic minority of Roma, close contact with known COVID-19 case, previous symptoms consistent with COVID-19, and mass gatherings were risk factors for seropositivity., Conclusion: The spread of SARS-CoV-2 during a period of lockdown in Greece was low in children and comparable to adults most likely due to intrafamilial transmission. Accordingly, it is unlikely that children have boosted virus transmission., What Is Known: • In the earliest months of the pandemic, it was demonstrated that children had significantly lower seroprevalence rates than the older age groups, due to the fact that children had decreased exposure to the virus, because of early public health interventions, such as school and day care closure. • Later, further studies reported that children have similar incidence rate of SARS-CoV-2 infection compared to adults in households and community settings., What Is New: • In this seroprevalence study, the spread of SARS-CoV-2 infection during a period of lockdown in Greece with the predominance of the Alpha-variant was particularly low in children and comparable to adults, most likely due to intrafamilial transmission. • These study findings will be useful for decisions regarding non-pharmaceutical interventions during the pandemic, and especially, to guide in designing and implementing appropriate containment measures for schools and social gatherings., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The aim of the present study was to assess the psychological impact of hospitalization during the COVID-19 pandemic on parents and their offspring. We performed a nationwide cross-sectional study in Greece based on an Internet questionnaire survey. A convenience sample of parents whose offspring had been hospitalized due to COVID-19 (including multisystem inflammatory syndrome in children, MIS-C), diagnosed with COVID-19 but not hospitalized, and hospitalized for another reason during the pandemic were enrolled. Parental stress was assessed using the Perceived Stress Scale (PSS) and the Revised Impact of Event Scale (IES-R) tools, and childhood mental wellbeing with the Children’s Revised Impact of Event 13 (CRIES-13) scale. Out of 214 received responses, stress levels were significantly higher in parents whose children had been admitted for COVID-19 or MIS-C versus those not admitted or admitted for other reasons (p < 0.001, for PSS/IES-R). Parental and childhood stress levels were correlated. In the multivariable linear regression analysis, children’s hospitalization because of COVID-19 or MIS-C, younger parental age, the existence of comorbidities, and another family member’s hospitalization because of COVID-19 were independent factors for higher stress. In light of the above, stricter hospital admission criteria for COVID-19 could be implemented, and psychological support for eventually admitted families may be beneficial.

Background: SARS-CoV-2 infects through the respiratory route and triggers inflammatory response by affecting multiple cell types including type II alveolar epithelial cells. SARS-CoV-2 triggers signals via its Spike (S) protein, which have been shown to participate in the pathogenesis of COVID19., Aim: Aim of the present study was to investigate the effect of SARS-CoV2 on type II alveolar epithelial cells, focusing on signals initiated by its S protein and their impact on the expression of inflammatory mediators., Results: For this purpose A549 alveolar type II epithelial cells were exposed to SARS CoV2 S recombinant protein and the expression of inflammatory mediators was measured. The results showed that SARS-CoV-2 S protein decreased the expression and secretion of IL8, IL6 and TNFα, 6 hours following stimulation, while it had no effect on IFNα, CXCL5 and PAI-1 expression. We further examined whether SARS-CoV-2 S protein, when combined with TLR2 signals, which are also triggered by SARS-CoV2 and its envelope protein, exerts a different effect in type II alveolar epithelial cells. Simultaneous treatment of A549 cells with SARS-CoV-2 S protein and the TLR2 ligand PAM3csk4 decreased secretion of IL8, IL6 and TNFα, while it significantly increased IFNα, CXCL5 and PAI-1 mRNA expression. To investigate the molecular pathway through which SARS-CoV-2 S protein exerted this immunomodulatory action in alveolar epithelial cells, we measured the induction of MAPK/ERK and PI3K/AKT pathways and found that SARS-CoV-2 S protein induced the activation of the serine threonine kinase AKT. Treatment with the Akt inhibitor MK-2206, abolished the inhibitory effect of SARS-CoV-2 S protein on IL8, IL6 and TNFα expression, suggesting that SARS-CoV-2 S protein mediated its action via AKT kinases., Conclusion: The findings of our study, showed that SARS-CoV-2 S protein suppressed inflammatory responses in alveolar epithelial type II cells at early stages of infection through activation of the PI3K/AKT pathway. Thus, our results suggest that at early stages SARS-CoV-2 S protein signals inhibit immune responses to the virus allowing it to propagate the infection while in combination with TLR2 signals enhances PAI-1 expression, potentially affecting the local coagulation cascade., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Al-Qahtani, Pantazi, Alhamlan, Alothaid, Matou-Nasri, Sourvinos, Vergadi and Tsatsanis.)

Group B Streptococcus (GBS) is a gram-positive bacterium that is harmless for healthy individuals but may provoke invasive disease in young infants and immunocompromised hosts. GBS invades the epithelial barriers to enter the bloodstream, and thus strategies that enhance epithelial cell responses may hamper GBS invasion. In the present study, we sought to investigate whether the inhibition of Akt, a kinase that regulates host inflammatory responses and autophagy via suppression of mTOR, can enhance the response of non-phagocytic alveolar epithelial cells against GBS. Treatment of the alveolar epithelial cell line A549 with the Akt inhibitor MK-2206 resulted in the enhanced production of reactive oxygen species and inflammatory mediators in response to GBS. Additionally, Akt inhibition via MK-2206 resulted in elevated LC3II/I ratios and increased autophagic flux in alveolar epithelial cells. Importantly, the inhibition of Akt promoted GBS clearance both in alveolar epithelial cells in vitro and in lung tissue in vivo in a murine model of GBS pneumonia. The induction of autophagy was essential for GBS clearance in MK-2206 treated cells, as knockdown of ATG5, a critical component of autophagy, abrogated the effect of Akt inhibition on GBS clearance. Our findings highlight the role of Akt kinase inhibition in promoting autophagy and GBS clearance in the alveolar epithelium. The inhibition of Akt may serve as a promising measure to strengthen epithelial barriers and prevent GBS invasion in susceptible hosts.

Aim: We studied the incidence and time course of any coronary artery changes in children up to 2 years of age who were hospitalised with mild COVID-19., Methods: This was a single-centre prospective study of 29 children (19 males) with a median age of 3 months and interquartile range (IQR) of 1.6-4.3 months. They were admitted to a Greek University hospital for mild COVID-19 from 1 March to 30 December 2021. Three echocardiographic evaluations were performed at a median (IQR) of 19 (16-24) days, 82 (75-89) days and 172 (163-197) after the first symptoms. The prevalence of coronary artery dilation, regression, and changes was documented., Results: Coronary artery dilation was present in 3 (10.3%) cases at the first evaluation, with complete regression at the second. Regression was observed in 18/24 (75%) cases with follow-up data and 9 (31%) demonstrated significant z-score changes of >2. Coronary artery changes in any segment at any time were documented in 18/29 (62%) of the patients., Conclusion: Cases of transient and very mild coronary artery dilatation following mild COVID-19 completely regressed within 3 months. Large-scale studies are needed to document the extent and time course of coronary artery dilation following paediatric COVID-19., (© 2022 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Multisystem inflammatory syndrome in children (MIS-C) may develop as a rare complication following COVID-19. MIS-C presentation varies substantially, but fever and gastrointestinal symptoms are the most prominent. Indeed, gastrointestinal involvement may be severe enough to present as acute abdomen, posing challenges to clinicians. We present herein the case of a healthy five-year-old male who presented with fever, vomiting, and abdominal pain, resembling acute abdomen. The patient had no history of SARS-CoV-2 infection or exposure, and MIS-C diagnosis was initially surpassed unnoticed. The patient underwent exploratory laparotomy that only revealed mesenteric lymphadenitis. Postoperatively, the patient met the clinical and laboratory diagnostic criteria of MIS-C. SARS-CoV-2 exposure was serologically confirmed and MIS-C treatment was commenced, resulting in defervescence and a satisfactory outcome. In young patients presenting with acute abdomen, surgeons should be aware of MIS-C, so that earlier diagnosis and appropriate treatment are made prior to surgical interventions.

Background: Desert dust outbreaks and dust storms are the major source of particulate matter globally and pose a major threat to human health. We investigated the microorganisms transported with desert dust particles and evaluated their potential impact on human health., Methods: A systematic review of all reports on the association between non-anthropogenic desert dust pollution, dust microorganisms and human health is conducted., Results: In total, 51 articles were included in this review. The affected regions studied were Asia (32/51, 62.7%) followed by Europe (9/51, 17.6%), America (6/51, 11.8%), Africa (4/51, 7.8%) and Australia (1/51, 2.0%). The Sahara Desert was the most frequent source of dust, followed by Asian and American deserts. In 39/51 studies the dust-related microbiome was analyzed, while, in 12/51 reports, the association of desert dust with infectious disease outbreaks was examined. Pathogenic and opportunistic agents were isolated from dust in 24/39 (61.5%) and 29/39 (74.4%) of the studies, respectively. A significant association of dust events with infectious disease outbreaks was found in 10/12 (83.3%) reports. The infectious diseases that were mostly investigated with dust outbreaks were pneumonia, respiratory tract infections, COVID-19, pulmonary tuberculosis and coccidioidomycosis., Conclusions: Desert dust outbreaks are vehicles of a significant number of pathogenic or opportunistic microorganisms and limited data indicate an association between dust events and infectious disease outbreaks. Further research is required to strengthen the correlation between dust events and infectious diseases and subsequently guide preventive public health measures.

Vaccination of healthcare professionals (HCPs) is a key measure to prevent infections in healthcare facilities, but uptake rates often remain low. Mandatory vaccination policies have been occasionally implemented to increase compliance among HCPs, but this remains an issue of controversy. The purpose of this survey was to assess the attitudes and beliefs of trainee HCPs towards mandatory occupational vaccination and further explore the factors that determine their decision. In this cross-sectional survey, trainees consisted of medical residents and medical and nursing students undergoing their clinical clerkship. An anonymous questionnaire was distributed following pilot testing. In total, 410 trainees participated (response rate: 90.1%), of whom 194 (47.3%) were residents, 154 (37.6%) medical and 62 (15.1%) nursing students. Most participants (320/410, 78%) supported mandatory occupational vaccination, stating that it should be applied to promote public welfare and benefit (294/320, 91.9%) or should be a prerequisite for employment (271/320, 84.7%). Only 22/410 (5.4%) of HCPs opposed to mandatory occupational vaccination. The primary reasons for a negative attitude were the belief that personal rights outweigh public benefit (10/22, 45.5%) and the fear of side effects (9/22, 40.9%). Univariate analysis revealed that HCPs that have been informed by vaccination campaigns or had higher knowledge scores, were more likely to support mandatory occupational vaccination (OR 1.7, 95% CI: 1.1-2.7, p 0.038 and OR 1.7, 95% CI: 1.02- 2.7. p 0.044, respectively). In conclusion, most medical and nursing trainees in this study supported mandatory vaccination for HCPs. Focusing on continuing professional education on vaccines is important to positively determine HCPs' attitudes towards occupational vaccination and increase their vaccination uptake rates., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Aim: Multisystem inflammatory syndrome in children (MIS-C), a rare severe complication of SARS-CoV-2 infection, has been recently reported to mimic acute abdomen and lead to surgical interventions, posing challenges for clinicians. In this systematic review, we evaluated the rate of acute abdomen and abdominal surgical emergencies in children with MIS-C., Methods: Systematic review of all MIS-C cases presented with acute abdomen., Results: A total of 385 patients with MIS-C, from 38 studies, were included. Gastrointestinal manifestations were prominent in 233/385 (60.5%) children. Acute abdomen was noted in 72/385 (18.7%) of MIS-C cases and in 72/233 (30.9%) of MIS-C cases with gastrointestinal symptoms. Final diagnoses were mostly non-surgical (55/72, 76.4%), such as mesenteric lymphadenitis (23/72, 31.9%), terminal ileitis/ileocolitis (19/72, 26.4%), free abdominal fluid/ascites (8/72, 11.1%) and paralytic ileus (3/72, 4.2%). Laparotomy was performed in 35/72 (48.6%) of children with MIS-C, and acute abdomen and was proven unnecessary in 18/35 (51.4%) cases. True abdominal surgical emergencies, such as appendicitis and obstructive ileus, were confirmed in 17/72 (23.6%) cases., Conclusion: MIS-C often presents with acute abdomen, mostly due to non-surgical intestinal inflammatory pathology. However, surgical complications occur in patients with MIS-C; therefore, a high index of suspicion should remain., (© 2021 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Introduction: Glucose transporter type 1 (Glut1) deficiency syndrome is a treatable neurometabolic disorder characterized by seizures, developmental delay, and hypoglycorrhachia. Due to the rareness and non-specific clinical manifestations, it is usually mis- or underdiagnosed., Case Presentation: We report the case of a toddler who presented with afebrile epileptic seizures and abnormal gait. Brain imaging and electroencephalogram were normal. Further investigation of the cerebrospinal fluid revealed hypoglycorrhachia that was the clue to the diagnosis of Glut1 deficiency syndrome and the initiation of treatment with ketogenic diet., Conclusion: Our case highlights the importance of lumbar puncture while investigating a child with epileptic seizures and abnormal gait or developmental delay, in order not to miss treatable neurometabolic conditions, such as Glut1 deficiency syndrome., Competing Interests: The authors declare that they have no conflict of interest., (© 2022 Chinese Medical Association. Pediatric Investigation published by John Wiley & Sons Australia, Ltd on behalf of Futang Research Center of Pediatric Development.)

Encephalitis in children may lead to adverse outcomes and long-term neurodevelopmental sequelae. The prompt identification of the causative agent is important to guide proper management in cases with encephalitis; however, the etiology often remains undetermined. The use of polymerase chain reaction (PCR) analysis in the cerebrospinal fluid (CSF) has increased the diagnostic yield in encephalitis cases; however, it may be occasionally misleading. In this article, we describe the case of a male immunocompetent child with encephalitis in which human herpesvirus-7 (HHV-7) was detected in CSF by PCR. As the detection of HHV-7 DNA in the CSF alone is insufficient to prove an etiologic association of severe encephalitis in immunocompetent children, alternative diagnoses were pursued. Enterovirus (E-11) was detected by PCR analysis of the nasopharyngeal and rectal swabs of the male patient. The final diagnosis was facilitated by the findings in his sibling, which presented concurrently with enteroviral encephalitis. Failure to detect enterovirus in the CSF by PCR does not exclude enteroviral encephalitis; screening of other samples, from other body sites, may be necessary to identify the virus, and physicians should take into consideration all evidence, including history, clinical presentation, and sick contacts' clinical status.

Macrophages, the central mediators of innate immune responses, being in the first-line of defense, they have to readily respond to pathogenic or tissue damage signals to initiate the inflammatory cascade. Such rapid responses require energy to support orchestrated production of pro-inflammatory mediators and activation of phagocytosis. Being a cell type that is present in diverse environments and conditions, macrophages have to adapt to different nutritional resources. Thus, macrophages have developed plasticity and are capable of utilizing energy at both normoxic and hypoxic conditions and in the presence of varying concentrations of glucose or other nutrients. Such adaptation is reflected on changes in signaling pathways that modulate responses, accounting for the different activation phenotypes observed. Macrophage metabolism has been tightly associated with distinct activation phenotypes within the range of M1-like and M2-like types. In the context of diseases, systemic changes also affect macrophage metabolism, as in diabetes and insulin resistance, which results in altered metabolism and distinct activation phenotypes in the adipose tissue or in the periphery. In the context of solid tumors, tumor-associated macrophages adapt in the hypoxic environment, which results in metabolic changes that are reflected on an activation phenotype that supports tumor growth. Coordination of environmental and pathogenic signals determines macrophage metabolism, which in turn shapes the type and magnitude of the response. Therefore, modulating macrophage metabolism provides a potential therapeutic approach for inflammatory diseases and cancer., (© 2021 The Author(s) Published by S. Karger AG, Basel.)

Macrophages display an array of activation phenotypes depending on the activation signal and the cellular microenvironment. The type and magnitude of the response depend on signaling molecules as well as on the epigenetic and metabolic status of the cells at the time of activation. The AKT family of kinases consists of three isoforms encoded by independent genes possessing similar functions and structures. Generation of research tools such as isoform-specific gene deletion mutant mice and cells and isoform-specific antibodies has allowed us to understand the role of each kinase isoform in macrophage activation and homeostasis. This chapter discusses the current evidence on the role of AKT kinases in macrophage activation, polarization, and homeostasis, highlighting the gaps in knowledge and future challenges in the field., (© 2022. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Streptococcus pseudoporcinus is a newly recognized β-hemolytic streptococcus, that is considered a rare pathogen in adults. Infections in children have not been reported. We describe a child with Klippel-Trenaunay syndrome that developed of S. pseudoporcinus cellulitis and bacteremia, which was difficult-to-treat, relapsed and required prolonged antibiotic courses. S. pseudoporcinus can cause invasive infection in children, especially in the presence of predisposing conditions., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Aim: Co-infections with viral and bacterial enteropathogens often augment severity of diarrhoea, however, there is limited evidence on the clinical importance of bacterial enteric co-infections. We investigated the rate, type and impact of bacterial enteropathogens and their associations in children with gastroenteritis., Methods: Retrospective cohort study that included children 0-18 years old with acute bacterial diarrhoea during a 27-year period (1993-2019), in Crete, Greece. Differences in clinical characteristics and pathogen associations were investigated between single and multiple infections., Results: Two or more bacteria were isolated in stool culture in 53 out of 1932 children (2.74%). Patients with co-infections were younger (p 0.0001) and had higher hospitalisation rates (p 0.03). Escherichia coli (E. coli) was the most prevalent pathogen associated with co-infections, in particular the E. coli enteropathogenic strains O127 and O111 (p 0.001), and Salmonella spp the least (p 0.001). Co-occurrence analysis revealed two positively associated pathogen pairs, E. coli with Campylobacter spp and E. coli (p 0.001) with Salmonella spp (p 0.04)., Conclusion: Bacterial enteropathogen co-infection was most common with E. coli strains and related to higher hospitalisation rates and younger age., (©2021 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

The major cause of death in SARS-CoV-2 infected patients is due to de-regulation of the innate immune system and development of cytokine storm. SARS-CoV-2 infects multiple cell types in the lung, including macrophages, by engagement of its spike (S) protein on angiotensin converting enzyme 2 (ACE2) receptor. ACE2 receptor initiates signals in macrophages that modulate their activation, including production of cytokines and chemokines. IL-1R-associated kinase (IRAK)-M is a central regulator of inflammatory responses regulating the magnitude of TLR responsiveness. Aim of the work was to investigate whether SARS-CoV-2 S protein-initiated signals modulate pro-inflammatory cytokine production in macrophages. For this purpose, we treated PMA-differentiated THP-1 human macrophages with SARS-CoV-2 S protein and measured the induction of inflammatory mediators including IL6, TNFα, IL8, CXCL5, and MIP1a. The results showed that SARS-CoV-2 S protein induced IL6, MIP1a and TNFα mRNA expression, while it had no effect on IL8 and CXCL5 mRNA levels. We further examined whether SARS-CoV-2 S protein altered the responsiveness of macrophages to TLR signals. Treatment of LPS-activated macrophages with SARS-CoV-2 S protein augmented IL6 and MIP1a mRNA, an effect that was evident at the protein level only for IL6. Similarly, treatment of PAM3csk4 stimulated macrophages with SARS-CoV-2 S protein resulted in increased mRNA of IL6, while TNFα and MIP1a were unaffected. The results were confirmed in primary human peripheral monocytic cells (PBMCs) and isolated CD14+ monocytes. Macrophage responsiveness to TLR ligands is regulated by IRAK-M, an inactive IRAK kinase isoform. Indeed, we found that SARS-CoV-2 S protein suppressed IRAK-M mRNA and protein expression both in THP1 macrophages and primary human PBMCs and CD14+ monocytes. Engagement of SARS-CoV-2 S protein with ACE2 results in internalization of ACE2 and suppression of its activity. Activation of ACE2 has been previously shown to induce anti-inflammatory responses in macrophages. Treatment of macrophages with the ACE2 activator DIZE suppressed the pro-inflammatory action of SARS-CoV-2. Our results demonstrated that SARS-CoV-2/ACE2 interaction rendered macrophages hyper-responsive to TLR signals, suppressed IRAK-M and promoted pro-inflammatory cytokine expression. Thus, activation of ACE2 may be a potential anti-inflammatory therapeutic strategy to eliminate the development of cytokine storm observed in COVID-19 patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Pantazi, Al-Qahtani, Alhamlan, Alothaid, Matou-Nasri, Sourvinos, Vergadi and Tsatsanis.)

Aim: Diagnosis and management of complicated mastoiditis in childhood are still controversial. We investigated the clinical manifestations, evaluation and management of children with mastoiditis complicated with cerebral venous sinus thrombosis., Methods: Retrospective cohort study that included all children admitted for acute mastoiditis over the last 5 years. Children were divided in two groups based on the presence or not of venous sinus thrombosis. Clinical, laboratory, imaging and management data were retrieved and compared., Results: Overall, 20 children with acute mastoiditis were included, of whom 5 had magnetic resonance imaging-confirmed cerebral venous sinus thrombosis and elevated intracranial pressure (ICP). In all complicated cases, neurological signs rather than mastoiditis signs, prevailed. The more prominent neurologic signs observed were lethargy (60%), nuchal rigidity (60%), abducens nerve palsy (60%) and ataxic gait (20%). Treatment consisted of intravenous antibiotics combined with anticoagulation. Surgery was performed in four children (4/5). Complicated cases had prolonged symptoms prior to admission (p 0.002), presented with neurologic signs and symptoms (p < 0.001), underwent more often lumbar puncture (p < 0.001) and brain imaging (p < 0.001), and were treated with prolonged courses of antibiotics and surgery (<0.001), compared to children with uncomplicated mastoiditis., Conclusion: Neurological signs and symptoms and elevated ICP dominate in children with mastoiditis complicated with thrombosis. Brain imaging is essential for early diagnosis of cerebral venous sinus complications and appropriate management., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The prevalence of extended-spectrum beta-lactamase producing Εnterobacteriaceae (ESBL-PE) is increasing globally. ESBL-PE are an important cause of urinary tract infections (UTIs) in children. We aimed to characterize the clinical presentation, treatment and outcomes of childhood UTI caused by ESBL-PE in Europe., Methods: Multicenter retrospective cohort study. Children 0 to 18 years of age with fever, positive urinalysis and positive urine culture for an ESBL-PE uropathogen, seen in a participating hospital from January 2016 to July 2017, were included., Main Outcome Measures: Primary outcome measure: day of defervescence was compared between (1) initial microbiologically effective treatment (IET) versus initial microbiologically ineffective treatment (IIT) and (2) single initial antibiotic treatment versus combined initial antibiotic treatment., Secondary Outcome Measures: Clinical and microbiologic failure of initial treatment., Results: We included 142 children from 14 hospitals in 8 countries. Sixty-one children had IET and 77 IIT. There was no statistical difference in time to defervescence for effective/ineffective groups (P = 0.722) and single/combination therapy groups (P = 0.574). Two of 59 (3.4%) and 4/66 (6.1%) patients exhibited clinical failure during treatment (P = 0.683) when receiving IET or IIT, respectively. Eight of 51 (15.7%) receiving IET and 6/58 (10.3%) receiving IIT patients (P = 0.568) had recurring symptoms/signs suggestive of a UTI. Recurrence of a UTI occurred 15.5 days (interquartile range, 9.0-19.0) after the end of treatment., Conclusions: Time to defervescence and clinical failure did not differ between IET/IIT groups. Non-carbapenem beta-lactam antibiotics may be used for the empiric treatment of ESBL febrile UTIs, until susceptibility testing results become available.

Vaccination is recommended for healthcare professionals (HCPs) to protect them against vaccine-preventable diseases (VPDs); however, uptake rates are low. This study aimed to evaluate HCPs' influenza, hepatitis B, and measles vaccine uptake in all healthcare levels in Crete, Greece. We conducted a questionnaire-based, cross-sectional multicenter study in 2018, including HCPs employed at 18 primary care centers and 3 hospitals. Overall, 2,246 HCPs responded (57.2% of the target population). The influenza vaccine uptake rate was 36.1% (810/2,246), with the annual vaccination rate at 14.8% (332/2,246) over the previous 5 years. Concurrently, the hepatitis B 3-dose vaccine uptake rate was 60.3% (1,316/2,181). Among the participating HCPs, 70.7% (1,457/2,061) had measles immunity due to previous illness (959/2,061, 46.5%), a 2-dose vaccination scheme (461/2,061, 22.4%), or serological confirmation (37/2,061, 1.8%). Vaccine uptake rates differed between groups depending on age, profession, and workplace setting. Logistic regression analysis revealed that risk factors for no influenza vaccine uptake during the previous season were younger age (≤45 years; odds ratio [OR] 1.35, 95% confidence interval [CI]: 1.08-1.66), profession other than physician (OR 2.94, 95%CI: 2.09-4.12), and working in hospitals (OR 1.39, 95%CI 1.02-1.89). Older age (>45 years) was an independent risk factor for not receiving a measles (OR 26.74, 95%CI: 17.41-41.06) or hepatitis B vaccine (OR 1.36, 95%CI 1.09-1.7). Working in primary care was an independent risk factor for not getting a hepatitis B vaccine (OR 1.52, 95%CI: 1.15-2.1). Our findings indicate that individualized and targeted interventions should be implemented to increase vaccine uptake among HCPs.

Acute Q fever is usually asymptomatic or is associated with a mild self-limited course and a favorable outcome. The occurrence of endocarditis during acute infection by Coxiella burnetii is an emerging clinical entity observed in adults that has been attributed to an autoimmune complication of early infection. Herein, we report the first case of a previously healthy 2-year-old child with endocarditis complicated by septic embolic stroke, in which the identified microbiological evidence was suggestive of acute rather than chronic C. burnetii infection. The development of endocarditis in this case occurred in the absence of any autoimmune reaction, but in the context of a very mild form of congenital heart disease, a small ventricular septal defect, which might serve as a predisposing factor for endocarditis. This case suggests that acute Q fever endocarditis may affect children as well and can be attributed not only to autoimmune mechanisms but also to a potential effect of the infectious agent per se on the cardiac endothelium in patients with underlying heart defects, regardless of their severity.

Aim: We investigated the impact of any antibiotic exposure on unusual and resistant pathogens in children with a urinary tract infection (UTI)., Methods: This was a retrospective cohort study of 695 children (54% female) hospitalised with 711 UTI episodes at Heraklion University Hospital, Greece, from January 2007 to December 2017. Three groups were studied: no previous antibiotic exposure, ongoing prophylaxis and short-term exposure to antibiotics in the last six months., Results: The median age at hospitalisation was 0.8 years (range 25 days to 15.9 years). Previous short-term exposure and prophylaxis were important determinants of non-Escherichia coli (E. coli) (OR 2.05, 95% CI 1.25-3.36, P = .0017 and OR 3.84, 95% CI 2.32-6.34, P < .0001, respectively) and extended-spectrum beta-lactamase-positive uropathogens (OR 2.43, 95% CI 1.36-4.32, P = .0025 and OR 2.63, 95% CI 1.31-5.33, P = .0070, respectively). Short-term antibiotics in the last 30 days or intravenous antibiotics were mostly associated with non-E. coli pathogens (OR 6.71 and OR 2.55, respectively). The most important determinants of E. coli resistance were short-term antibiotics for ampicillin (OR 2.58) and prophylaxis for cotrimoxazole (OR 2.64)., Conclusion: Recent short-term exposure to antibiotics and ongoing prophylaxis both had a significant impact on the type and resistance of uropathogens., (© 2019 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Dent disease is a rare X-linked renal proximal tubulopathy presenting with low-molecular-weight proteinuria (LMWP), hypercalciuria, and nephrocalcinosis, other signs of incomplete renal Fanconi syndrome, and renal failure. Early identification of patients who harbor disease-associated mutations is important for effective medical care and avoidance of unnecessary interventions. We report the case of an asymptomatic 9-year-old boy who presented with proteinuria in routine examination. Further investigation revealed the presence of nephrotic range proteinuria, mostly LMWP and mild hypercalciuria without nephrocalcinosis, or other features of tubular dysfunction. Renal function, growth, and bone mineral density were within regular limits. The male gender and the presence of LMWP and hypercalciuria even in the absence of other findings prompted us to genetic investigation for Dent disease. A novel splice site mutation (c.416-2A > G) of the chloride voltage-gated channel 5 ( CLCN5 ) gene, responsible for Dent disease type 1 was identified. In silico analysis revealed that this mutation interferes with the mating of exons 4 and 5. Due to early molecular diagnosis, our patient did not undergo a renal biopsy, neither required aggressive pharmacological interventions. This case underscores the diversity and complexity of CLCN5 mutations and highlights the importance of early molecular testing in male patients with incomplete phenotype of Dent disease., (© Thieme Medical Publishers.)

Obesity and insulin resistance influences metabolic processes, but whether it affects macrophage metabolism is not known. In this study, we demonstrate that chronic exposure of macrophages to insulin either in culture or in vivo in diet-induced, glucose-intolerant mice rendered them resistant to insulin signals marked by failure to induce Akt2 phosphorylation. Similarly, macrophages lacking Akt2 or IGF1 receptor were also resistant to insulin signals. Insulin-resistant macrophages had increased basal mTORC1 activity, possessed an M2-like phenotype, and reduced LPS responses. Moreover, they exhibited increased glycolysis and increased expression of key glycolytic enzymes. Inhibition of mTORC1 reversed the M2-like phenotype and suppressed glycolysis in insulin-resistant macrophages. In the context of polymicrobial sepsis, mice harboring insulin-resistant macrophages exhibited reduced sepsis-induced lung injury. Thus, macrophages obtain resistance to insulin characterized by increased glycolysis and a unique M2-like phenotype, termed M-insulin resistant, which accounts for obesity-related changes in macrophage responses and a state of trained immunity., (Copyright © 2019 by The American Association of Immunologists, Inc.)

Group B streptococcus (GBS) remains a leading cause of neonatal disease. However, GBS rates and prevention strategies vary considerably worldwide. Herein, we investigated the burden and epidemiological trends of neonatal GBS infections in our area (Greece) over the last two decades. We conducted a multicenter retrospective study that includes all cases of culture-proven GBS disease in infants <90 days old in the last 22 years. Neonatal GBS incidence was 0.17/1000 live births (95%CI: 0.11-0.21). A significant increase was noted during the second decade (0.23 vs 0.10/1000, P<0.05). Late onset disease (LOD) significantly increased during the second decade (0.08 vs 0.02, P<0.05). Infants in the LOD group had a higher risk of meningitis (RR 1.8, 95%CI: 1.23-2.71). Long-term neurological sequelae were reported in 42.8% of meningitis cases. The mortality rate was 8%. The incidence of neonatal GBS disease in our area is among the lowest reported, but an increase was noted the last decade mainly due a rise in the LOD. The burden of LOD, the mortality and long-term disability are still substantial, thus effective prevention strategies - including maternal vaccination for neonatal GBS - are needed., Competing Interests: Conflict of interest: the authors declare no conflict of interest.

The onset and the termination of innate immune response must be tightly regulated to maintain homeostasis and prevent excessive inflammation, which can be detrimental to the organism, particularly in the context of sepsis. Endotoxin tolerance and compensatory anti-inflammatory response syndrome (CARS) describe a state of hypo-responsiveness characterized by reduced capacity of myeloid cells to respond to inflammatory stimuli, particularly those initiated by bacterial lipopolysaccharide (LPS). To achieve endotoxin tolerance, extensive reprogramming otherwise termed as "innate immune training", is required that leads to both modifications of the intracellular components of TLR signaling and also to alterations in extracellular soluble mediators. Non-coding RNAs (ncRNAs) have been recognized as critical regulators of TLR signaling. Specifically, several microRNAs (miR-146, miR-125b, miR-98, miR-579, miR-132, let-7e and others) are induced upon TLR activation and reciprocally promote endotoxin tolerance and/or cross tolerance. Many other miRNAs have been also shown to negatively regulate TLR signaling. The long non-coding (lnc)RNAs (Mirt2, THRIL, MALAT1, lincRNA-21 and others) are also altered upon TLR activation and negatively regulate TLR signaling. Furthermore, the promotion or termination of myeloid cell tolerance is not only regulated by intracellular mediators but is also affected by other TLR-independent soluble signals that often achieve their effect via modulation of intracellular ncRNAs. In this article, we review recent evidence on the role of different ncRNAs in the context of innate immune cell tolerance and trained immunity, and evaluate their impact on immune system homeostasis.

Since the discovery of non-coding RNAs (ncRNAs) a new area has emerged in the field of biomarkers. NcRNAs are RNA molecules of different sizes that are transcribed as independent genes or as part of protein coding genes and are not translated, therefore they do not produce proteins. They have been classified according to their size and function and include microRNAs (miRNAs), piwiRNAs (piRNAs), snoRNAs and long non-coding RNAs (lncRNAs). These non-coding RNAs are present in different cell compartments participating in multiple cell functions, but they have also been identified in biological fluids, also known as cell-free or circulating ncRNAs, where they can be detected in exosomes, bound on lipoproteins as well as free circulating molecules. The role of circulating ncRNAs is still under investigation but are believed to be paracrine or endocrine messengers to systematically deliver signals between cells and tissues. Detecting ncRNAs in biological fluids has opened a new field in Clinical Chemistry utilizing them as biomarkers of diseases or prognostic markers for different pathological conditions. Herein, the different types of ncRNAs and their potential in the field of diagnostics are outlined.

Cystinosis is a rare autosomal recessive lysosomal transport disorder, characterized by the accumulation of the aminoacid cystine and progressive dysfunction of several organs. Kidneys are severely affected, and the most frequent form, infantile nephropathic cystinosis, presents with growth failure in infancy, renal Fanconi syndrome and end-stage renal disease by the first decade of life. We report of a girl with infantile nephropathic cystinosis that has reached adolescence without the need of renal replacement therapy and without extrarenal manifestations despite her delayed diagnosis and treatment initiation. The girl with this intermediate phenotype was found to have compound heterozygosity of one known (1015G > A) and one novel (587&#95;588insA) mutation in CTNS gene. Our case points to the wide clinical presentation of infantile nephropathic cystinosis and suggest that long-term outcome is not always ominous as generally thought.

Introduction: Urinary tract infection (UTI) is a common bacterial infection in childhood with favourable outcome. However, the recent emergence of UTI caused by multidrug-resistant pathogens, such as carbapenem-resistant Enterobacteriaceae (CRE), has become a great concern worldwide. CRE are mainly responsible for nosocomial infections and community-onset CRE infections in healthy individuals are rare., Objectives: In this study, we report a series of infants without substantial genitourinary abnormalities that were admitted with community-onset urinary tract infections (UTIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) and we discuss their aetiology., Methods: We retrospectively reviewed the medical records of nine infants who presented from community to the paediatric ward with CRKP urinary tract infections, as well as all affected neonates of a concomitant CRKP outbreak that occurred in the neonatal intensive care unit (NICU) in a tertiary hospital (period from April 2009 to July 2012). We further retrieved all culture-proven CRKP infections of any site from 2007 to 2015 in our paediatric department., Results: Over a 33-month period, nine infants, all males, aged 0.9-19.3 (median 4.0) months, were admitted to the Department of Paediatrics with UTI caused by CRKP. Three of them were diagnosed with urinary tract abnormalities but only one had vesicoureteral reflux (VUR), which was a UTI-associated one. History revealed that they had all been hospitalised in the same NICU during a concurrent long-lasting CRKP outbreak for a median of 17 (2-275) days and thereafter presented with CRKP UTI 15 to 207 (median 41) days after NICU discharge. The antibiotic susceptibility and phenotypic characteristics were identical among all isolates in NICU and the paediatric ward. The summary Figure shows a timeline of NICU hospitalisation indicative of its duration and subsequent CRKP UTI of study participants is presented., Conclusions: These cases illustrate that UTI caused by multidrug-resistant pathogens does not necessarily imply an underlying urinary track anomaly. Hospital acquisition of CRKP may well provoke community-onset multidrug-resistant UTI in infants months later, and this highlights the value of detailed history in patients with unusual pathogens. Cautious use of broad-spectrum antibiotics in NICUs and infection control measures would minimise the spread of multidrug-resistant pathogens in infants in the community., (Copyright © 2017 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Macrophages become activated initiating innate immune responses. Depending on the signals, macrophages obtain an array of activation phenotypes, described by the broad terms of M1 or M2 phenotype. The PI3K/Akt/mTOR pathway mediates signals from multiple receptors including insulin receptors, pathogen-associated molecular pattern receptors, cytokine receptors, adipokine receptors, and hormones. As a result, the Akt pathway converges inflammatory and metabolic signals to regulate macrophage responses modulating their activation phenotype. Akt is a family of three serine-threonine kinases, Akt1, Akt2, and Akt3. Generation of mice lacking individual Akt, PI3K, or mTOR isoforms and utilization of RNA interference technology have revealed that Akt signaling pathway components have distinct and isoform-specific roles in macrophage biology and inflammatory disease regulation, by controlling inflammatory cytokines, miRNAs, and functions including phagocytosis, autophagy, and cell metabolism. Herein, we review the current knowledge on the role of the Akt signaling pathway in macrophages, focusing on M1/M2 polarization and highlighting Akt isoform-specific functions., (Copyright © 2017 by The American Association of Immunologists, Inc.)

Nitric oxide (NO), the first gas known to act as a biological messenger, is one of the most widely studied free radical/gas in medicine, both for its biological function and therapeutic applications. The measurement of endogenous NO in exhaled air is widely used in the evaluation of lung disorders. Partitioning of exhaled nitric oxide (eNO) is of increasing interest because of the additional information about lung pathology and distal lung inflammation that can be obtained. Specifically, measuring exhaled NO at multiple flow rates allows assessment of the flow-independent NO parameters: alveolar NO concentration (CalvNO), bronchial NO flux (JNO), bronchial wall NO concentration (CWNO), and bronchial diffusing capacity of NO (DNO). Several studies have reported that there were different patterns of those parameters in different airway diseases and/or in different severities of the same disease, mostly in asthma. Specifically, while JNO seems to provide the same information as FeNO50, alveolar NO concentration appears to be an independent parameter that is putatively associated with increased distal lung inflammation and more severe disease. However, despite much research interest in partitioning exhaled NO, clinical usefulness has yet to be established.

Background: Mechanical stress induced by injurious ventilation leads to pro-inflammatory cytokine production and lung injury. The extracellular-signal-regulated-kinase, ERK1/2, participates in the signaling pathways activated upon mechanical stress in the lungs to promote the inflammatory response. Tumor progression locus 2 (Tpl2) is a MAP3kinase that activates ERK1/2 upon cytokine or TLR signaling, to induce pro-inflammatory cytokine production. The role of Tpl2 in lung inflammation, and specifically in the one caused by mechanical stress has not been investigated. The aim of the study was to examine if genetic or pharmacologic inhibition of Tpl2 could ameliorate ventilator-induced lung injury., Methods: Adult male wild-type and Tpl2-deficient mice were ventilated with normal or high tidal volume for 4 h. Additional wild-type mice were treated with a Tpl2 inhibitor either before or 30 min after initiation of high tidal ventilation. Non-ventilated mice of both genotypes served as controls. The development of lung injury was evaluated by measuring lung mechanics, arterial blood gases, concentrations of proteins, IL-6, and MIP-2 in bronchoalveolar lavage fluid (BALF) and by lung histology. Data were compared by Kruskal-Wallis non-parametric test and significance was defined as p < 0.05., Results: Mechanical ventilation with normal tidal volume induced a mild increase of IL-6 in BALF in both strains. High tidal volume ventilation induced lung injury in wild-type mice, characterized by decreased lung compliance, increased concentrations of proteins, IL-6 and MIP-2 in BALF, and inflammatory cell infiltration on histology. All indices of lung injury were ameliorated in Tpl2-deficient mice. Wild-type mice treated with the Tpl2 inhibitor, either prior of after the initiation of high tidal volume ventilation were protected from the development of lung injury, as indicated by preserved lung compliance and lower BALF concentrations of proteins and IL-6, than similarly ventilated, untreated wild-type mice., Conclusions: Genetic and pharmacologic inhibition of Tpl2 is protective in a mouse model of ventilator-induced lung injury, ameliorating both high-permeability pulmonary edema and lung inflammation.

Acute respiratory distress syndrome (ARDS) is a major cause of respiratory failure, with limited effective treatments available. Alveolar macrophages participate in the pathogenesis of ARDS. To investigate the role of macrophage activation in aseptic lung injury and identify molecular mediators with therapeutic potential, lung injury was induced in wild-type (WT) and Akt2(-/-) mice by hydrochloric acid aspiration. Acid-induced lung injury in WT mice was characterized by decreased lung compliance and increased protein and cytokine concentration in bronchoalveolar lavage fluid. Alveolar macrophages acquired a classical activation (M1) phenotype. Acid-induced lung injury was less severe in Akt2(-/-) mice compared with WT mice. Alveolar macrophages from acid-injured Akt2(-/-) mice demonstrated the alternative activation phenotype (M2). Although M2 polarization suppressed aseptic lung injury, it resulted in increased lung bacterial load when Akt2(-/-) mice were infected with Pseudomonas aeruginosa. miR-146a, an anti-inflammatory microRNA targeting TLR4 signaling, was induced during the late phase of lung injury in WT mice, whereas it was increased early in Akt2(-/-) mice. Indeed, miR-146a overexpression in WT macrophages suppressed LPS-induced inducible NO synthase (iNOS) and promoted M2 polarization, whereas miR-146a inhibition in Akt2(-/-) macrophages restored iNOS expression. Furthermore, miR-146a delivery or Akt2 silencing in WT mice exposed to acid resulted in suppression of iNOS in alveolar macrophages. In conclusion, Akt2 suppression and miR-146a induction promote the M2 macrophage phenotype, resulting in amelioration of acid-induced lung injury. In vivo modulation of macrophage phenotype through Akt2 or miR-146a could provide a potential therapeutic approach for aseptic ARDS; however, it may be deleterious in septic ARDS because of impaired bacterial clearance.

Lipodystrophies represent a group of heterogeneous disorders characterized by loss of fat tissue. However, the underlying mechanisms remain poorly understood. Using mice carrying an ERCC1-XPF DNA repair defect systematically or in adipocytes, we show that DNA damage signaling triggers a chronic autoinflammatory response leading to fat depletion. Ercc1-/- and aP2-Ercc1F/- fat depots show extensive gene expression similarities to lipodystrophic Pparγ(ldi/+) animals, focal areas of ruptured basement membrane, the reappearance of primary cilia, necrosis, fibrosis, and a marked decrease in adiposity. We find that persistent DNA damage in aP2-Ercc1F/- fat depots and in adipocytes ex vivo triggers the induction of proinflammatory factors by promoting transcriptionally active histone marks and the dissociation of nuclear receptor corepressor complexes from promoters; the response is cell autonomous and requires ataxia telangiectasia mutated (ATM). Thus, persistent DNA damage-driven autoinflammation plays a causative role in adipose tissue degeneration, with important ramifications for progressive lipodystrophies and natural aging., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Hypoxia induces an inflammatory response in the lung manifested by alternative activation of macrophages with elevation of proinflammatory mediators that are critical for the later development of hypoxic pulmonary hypertension. Mesenchymal stromal cell transplantation inhibits lung inflammation, vascular remodeling, and right heart failure and reverses hypoxic pulmonary hypertension in experimental models of disease. In this study, we aimed to investigate the paracrine mechanisms by which mesenchymal stromal cells are protective in hypoxic pulmonary hypertension., Methods and Results: We fractionated mouse mesenchymal stromal cell-conditioned media to identify the biologically active component affecting in vivo hypoxic signaling and determined that exosomes, secreted membrane microvesicles, suppressed the hypoxic pulmonary influx of macrophages and the induction of proinflammatory and proproliferative mediators, including monocyte chemoattractant protein-1 and hypoxia-inducible mitogenic factor, in the murine model of hypoxic pulmonary hypertension. Intravenous delivery of mesenchymal stromal cell-derived exosomes (MEX) inhibited vascular remodeling and hypoxic pulmonary hypertension, whereas MEX-depleted media or fibroblast-derived exosomes had no effect. MEX suppressed the hypoxic activation of signal transducer and activator of transcription 3 (STAT3) and the upregulation of the miR-17 superfamily of microRNA clusters, whereas it increased lung levels of miR-204, a key microRNA, the expression of which is decreased in human pulmonary hypertension. MEX produced by human umbilical cord mesenchymal stromal cells inhibited STAT3 signaling in isolated human pulmonary artery endothelial cells, demonstrating a direct effect of MEX on hypoxic vascular cells., Conclusion: This study indicates that MEX exert a pleiotropic protective effect on the lung and inhibit pulmonary hypertension through suppression of hyperproliferative pathways, including STAT3-mediated signaling induced by hypoxia.

The aim of this study was to investigate the changes induced by high tidal volume ventilation (HVTV) in pulmonary expression of micro-RNAs (miRNAs) and identify potential target genes and corresponding miRNA-gene networks. Using a real-time RT-PCR-based array in RNA samples from lungs of mice subjected to HVTV for 1 or 4 h and control mice, we identified 65 miRNAs whose expression changed more than twofold upon HVTV. An inflammatory and a TGF-β-signaling miRNA-gene network were identified by in silico pathway analysis being at highest statistical significance (P = 10(-43) and P = 10(-28), respectively). In the inflammatory network, IL-6 and SOCS-1, regulated by miRNAs let-7 and miR-155, respectively, appeared as central nodes. In TGF-β-signaling network, SMAD-4, regulated by miR-146, appeared as a central node. The contribution of miRNAs to the development of lung injury was evaluated in mice subjected to HVTV treated with a precursor or antagonist of miR-21, a miRNA highly upregulated by HVTV. Lung compliance was preserved only in mice treated with anti-miR-21 but not in mice treated with pre-miR-21 or negative-control miRNA. Both alveolar-arterial oxygen difference and protein levels in bronchoalveolar lavage were lower in mice treated with anti-miR-21 than in mice treated with pre-miR-21 or negative-control miRNA (D(A-a): 66 ± 27 vs. 131 ± 22, 144 ± 10 mmHg, respectively, P < 0.001; protein concentration: 1.1 ± 0.2 vs. 2.3 ± 1, 2.1 ± 0.4 mg/ml, respectively, P < 0.01). Our results show that HVTV induces changes in miRNA expression in mouse lungs. Modulation of miRNA expression can affect the development of HVTV-induced lung injury.

Background: Parapneumonic effusions (PPE) and empyema, secondary to bacterial pneumonia, are relatively uncommon but their prevalence is increasing lately. Even if their prognosis is generally good, they may still cause significant morbidity. The traditional treatment of PPE has been intravenous antibiotics and, when necessary, chest tube drainage. Open thoracotomy with decortication has usually been applied in case of failure of the traditional approach. Lately, the use of fibrinolysis and/or video-assisted thoracoscopic surgery (VATS) are utilized in the management of PPE; however, there is still little consensus on the most effective primary treatment., Scope: In this article our goal was to summarize, based on up-to-date evidence, all the management options for PPE available to physicians and weigh the benefits and risks of the most popular ones, in an effort to figure out which one is superior as a first-line approach in children., Findings: A literature search of randomized and retrospective studies that pinpoint methods of evaluation and treatment of PPE was carried out in Medline and Scopus databases. Chest X-ray, ultrasound as well as microbiology and biochemical characteristics of the pleural fluid will facilitate decision-making. Small uncomplicated effusions resolve with antibiotics alone, larger ones require small-bore chest tube drainage and in case of complicated loculated PPE, fibrinolysis or VATS should be considered. Both methods promote faster drainage, reduce hospital stay and obviate the need for further interventions when used as first-line approach. However, primary treatment with VATS is not advised by the majority of studies as a first choice intervention, unless medical treatment has failed., Conclusion: The main steps in treatment are diagnostic thoracocentesis and imaging, small percutaneous drainage, and considering fibrinolysis in complicated PPE. In case of failure, VATS should be the surgical method to be applied.

Activated macrophages are described as classically activated or M1 type and alternatively activated or M2 type, depending on their response to proinflammatory stimuli and the expression of genetic markers including iNOS, arginase1, Ym1, and Fizz1. Here we report that Akt kinases differentially contribute to macrophage polarization, with Akt1 ablation giving rise to an M1 and Akt2 ablation resulting in an M2 phenotype. Accordingly, Akt2(-/-) mice were more resistant to LPS-induced endotoxin shock and to dextran sulfate sodium (DSS)-induced colitis than wild-type mice, whereas Akt1(-/-) mice were more sensitive. Cell depletion and reconstitution experiments in a DSS-induced colitis model confirmed that the effect was macrophage-dependent. Gene-silencing studies showed that the M2 phenotype of Akt2(-/-) macrophages was cell autonomous. The microRNA miR-155, whose expression was repressed in naive and in LPS-stimulated Akt2(-/-) macrophages, and its target C/EBPβ appear to play a key role in this process. C/EBPβ, a hallmark of M2 macrophages that regulates Arg1, was up-regulated upon Akt2 ablation or silencing. Overexpression or silencing of miR-155 confirmed its central role in Akt isoform-dependent M1/M2 polarization of macrophages.

Pulmonary arterial hypertension (PAH) remains a serious disease, and although current treatments may prolong and improve quality of life, search for novel and effective therapies is warranted. Using genetically modified mouse lines, we tested the ability of bone marrow-derived stromal cells (mesenchymal stem cells [MSCs]) to treat chronic hypoxia-induced PAH. Recipient mice were exposed for 5 weeks to normobaric hypoxia (8%-10% O(2)), MSC preparations were delivered through jugular vein injection and their effect on PAH was assessed after two additional weeks in hypoxia. Donor MSCs derived from wild-type (WT) mice or heme oxygenase-1 (HO-1) null mice (Hmox1(KO)) conferred partial protection from PAH when transplanted into WT or Hmox1(KO) recipients, whereas treatment with MSCs isolated from transgenic mice harboring a human HO-1 transgene under the control of surfactant protein C promoter (SH01 line) reversed established disease in WT recipients. SH01-MSC treatment of Hmox1(KO) animals, which develop right ventricular (RV) infarction under prolonged hypoxia, resulted in normal RV systolic pressure, significant reduction of RV hypertrophy and prevention of RV infarction. Donor MSCs isolated from a bitransgenic mouse line with doxycycline-inducible, lung-specific expression of HO-1 exhibited similar therapeutic efficacy only on doxycycline treatment of the recipients. In vitro experiments indicate that potential mechanisms of MSC action include modulation of hypoxia-induced lung inflammation and inhibition of smooth muscle cell proliferation. Cumulatively, our results demonstrate that MSCs ameliorate chronic hypoxia-induced PAH and their efficacy is highly augmented by lung-specific HO-1 expression in the transplanted cells, suggesting an interplay between HO-1-dependent and HO-1-independent protective pathways., (Copyright © 2010 AlphaMed Press.)