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Telemedicine and teleconsultation can be powerful and useful tools for patients to hamper the physical barriers to access to health care services during COVID-19 pandemic. We describe the teleconsultation (TC) model in the Lazio Region. It uses a hub-and-spoke network system on geographic regional basis using a web based digital platform, termed ADVICE with the aim to connect regional Emergency Departments (EDs) and Infectious Diseases (ID) acute and critical care settings for patients with acute ID syndrome. Between January 2020 and June 2021, the ADVICE platform received 18.686 TCs: of them, 10838 requests (58%) were for ID TCs in 7996 patients, followed by 2555(13%) requests for trauma, 2286(12%) for acute complex syndrome and 1681 (8%) for Stroke TCs. Three quarter of ID TCs were requested for SARS-COV-2 infection, followed by sepsis management in 7% and tuberculosis in 6%. In 5416 TCs, 68%, diagnostic investigations and therapeutic prescriptions were recommended before admission, in 1941 TCs, 24%, the recommendation was patient admission and in 608 TCs, 7%, was to discharge patient at home. Telemedicine have ensured high-profile consultations for ID patients and during COVID-19 the use of this resource optimized clinical patient management., (© 2022. The Author(s).)

Background: Omics data, driven by rapid advances in laboratory techniques, have been generated very quickly during the COVID-19 pandemic. Our aim is to use omics data to highlight the involvement of specific pathways, as well as that of cell types and organs, in the pathophysiology of COVID-19, and to highlight their links with clinical phenotypes of SARS-CoV-2 infection., Methods: The analysis was based on the domain model, where for domain it is intended a conceptual repository, useful to summarize multiple biological pathways involved at different levels. The relevant domains considered in the analysis were: virus, pathways and phenotypes. An interdisciplinary expert working group was defined for each domain, to carry out an independent literature scoping review., Results: The analysis revealed that dysregulated pathways of innate immune responses, (i.e., complement activation, inflammatory responses, neutrophil activation and degranulation, platelet degranulation) can affect COVID-19 progression and outcomes. These results are consistent with several clinical studies., Conclusions: Multi-omics approach may help to further investigate unknown aspects of the disease. However, the disease mechanisms are too complex to be explained by a single molecular signature and it is necessary to consider an integrated approach to identify hallmarks of severity., (© 2021. The Author(s).)

In the last months, many studies have clearly described several mechanisms of SARS-CoV-2 infection at cell and tissue level, but the mechanisms of interaction between host and SARS-CoV-2, determining the grade of COVID-19 severity, are still unknown. We provide a network analysis on protein-protein interactions (PPI) between viral and host proteins to better identify host biological responses, induced by both whole proteome of SARS-CoV-2 and specific viral proteins. A host-virus interactome was inferred, applying an explorative algorithm (Random Walk with Restart, RWR) triggered by 28 proteins of SARS-CoV-2. The analysis of PPI allowed to estimate the distribution of SARS-CoV-2 proteins in the host cell. Interactome built around one single viral protein allowed to define a different response, underlining as ORF8 and ORF3a modulated cardiovascular diseases and pro-inflammatory pathways, respectively. Finally, the network-based approach highlighted a possible direct action of ORF3a and NS7b to enhancing Bradykinin Storm. This network-based representation of SARS-CoV-2 infection could be a framework for pathogenic evaluation of specific clinical outcomes. We identified possible host responses induced by specific proteins of SARS-CoV-2, underlining the important role of specific viral accessory proteins in pathogenic phenotypes of severe COVID-19 patients., (© 2021. The Author(s).)

Complex systems are inherently multilevel and multiscale systems. The infectious disease system is considered a complex system resulting from the interaction between three sub-systems (host, pathogen, and environment) organized into a hierarchical structure, ranging from the cellular to the macro-ecosystem level, with multiscales. Therefore, to describe infectious disease phenomena that change through time and space and at different scales, we built a model framework where infectious disease must be considered the set of biological responses of human hosts to pathogens, with biological pathways shared with other pathologies in an ecological interaction context. In this paper, we aimed to design a framework for building a disease model for COVID-19 based on current literature evidence. The model was set up by identifying the molecular pathophysiology related to the COVID-19 phenotypes, collecting the mechanistic knowledge scattered across scientific literature and bioinformatic databases, and integrating it using a logical/conceptual model systems biology. The model framework building process began from the results of a domain-based literature review regarding a multiomics approach to COVID-19. This evidence allowed us to define a framework of COVID-19 conceptual model and to report all concepts in a multilevel and multiscale structure. The same interdisciplinary working groups that carried out the scoping review were involved. The conclusive result is a conceptual method to design multiscale models of infectious diseases. The methodology, applied in this paper, is a set of partially ordered research and development activities that result in a COVID-19 multiscale model.

Background: Epidemiological, virological and pathogenetic characteristics of SARS-CoV-2 infection are under evaluation. A better understanding of the pathophysiology associated with COVID-19 is crucial to improve treatment modalities and to develop effective prevention strategies. Transcriptomic and proteomic data on the host response against SARS-CoV-2 still have anecdotic character; currently available data from other coronavirus infections are therefore a key source of information., Methods: We investigated selected molecular aspects of three human coronavirus (HCoV) infections, namely SARS-CoV, MERS-CoV and HCoV-229E, through a network based-approach. A functional analysis of HCoV-host interactome was carried out in order to provide a theoretic host-pathogen interaction model for HCoV infections and in order to translate the results in prediction for SARS-CoV-2 pathogenesis. The 3D model of S-glycoprotein of SARS-CoV-2 was compared to the structure of the corresponding SARS-CoV, HCoV-229E and MERS-CoV S-glycoprotein. SARS-CoV, MERS-CoV, HCoV-229E and the host interactome were inferred through published protein-protein interactions (PPI) as well as gene co-expression, triggered by HCoV S-glycoprotein in host cells., Results: Although the amino acid sequences of the S-glycoprotein were found to be different between the various HCoV, the structures showed high similarity, but the best 3D structural overlap shared by SARS-CoV and SARS-CoV-2, consistent with the shared ACE2 predicted receptor. The host interactome, linked to the S-glycoprotein of SARS-CoV and MERS-CoV, mainly highlighted innate immunity pathway components, such as Toll Like receptors, cytokines and chemokines., Conclusions: In this paper, we developed a network-based model with the aim to define molecular aspects of pathogenic phenotypes in HCoV infections. The resulting pattern may facilitate the process of structure-guided pharmaceutical and diagnostic research with the prospect to identify potential new biological targets.

Objective: To make an informed viewpoint on the usefulness of Tuberculin Skin test (TST) compared to Interferon Gamma Release Assays (IGRAs) for diagnosis of Latent TB Infection (LTBI) in different geographical settings., Methods: We reviewed the current literature on TST compared to IGRA, including national implementation of WHO LTBI recommendations and retrospective data over the past 7 years at the National Institute for Infectious Diseases "L. Spallanzani" as indirect indicator of usage of both tests under actual programmatic conditions., Results: Current national guidelines vary considerably, reflecting the uncertainty and rapidly evolving evidence about the potential use of these tests. Data from Institute "L. Spallanzani" showed IGRA concordance in TST positive subjects only in 54.74% of subjects, while there was strong concordance between two tests in TST negative subjects (93.78%)., Conclusion: Neither IGRAs nor TST can distinguish active TB from LTBI. TST will continue to be clinically useful in low and high TB endemic areas until more accurate and predictive tests will become available. Clinical judgment remains fundamental in choosing between IGRA/TST tests and interpreting their results., (Copyright © 2019. Published by Elsevier Ltd.)

An unprecedented Ebola virus (EBOV) epidemic occurred in 2013-2016 in West Africa. Over this time the epidemic exponentially grew and moved to Europe and North America, with several imported cases and many Health Care Workers (HCW) infected. Better understanding of EBOV infection patterns in different body compartments is mandatory to develop new countermeasures, as well as to fully comprehend the pathways of human-to-human transmission. We have longitudinally explored the persistence of EBOV-specific negative sense genomic RNA (neg-RNA) and the presence of positive sense RNA (pos-RNA), including both replication intermediate (antigenomic-RNA) and messenger RNA (mRNA) molecules, in the upper and lower respiratory tract, as compared to plasma, in a HCW infected with EBOV in Sierra Leone, who was hospitalized in the high isolation facility of the National Institute for Infectious Diseases "Lazzaro Spallanzani" (INMI), Rome, Italy. We observed persistence of pos-RNA and neg-RNAs in longitudinally collected specimens of the lower respiratory tract, even after viral clearance from plasma, suggesting possible local replication. The purpose of the present study is to enhance the knowledge on the biological features of EBOV that can contribute to the human-to-human transmissibility and to develop effective intervention strategies. However, further investigation is needed in order to better understand the clinical meaning of viral replication and shedding in the respiratory tract., Competing Interests: The authors have declared that no competing interests exist.

The unprecedented epidemic of Ebola virus disease (EVD) in West Africa highlighted the need for stronger systems for disease surveillance, response, and prevention worldwide. Tackling an epidemic event today requires a broader view, not only limited to medical management of the patients, but which also includes heroic efforts by clinicians and public health personnel.Since its foundation in 1936, INMI has been devoted to the prevention, diagnosis and care for infectious diseases. In 2009, INMI became a WHO collaborative center for clinical care, diagnosis, response and training on Highly Infectious Diseases. This paper is aimed to present the activities and the challenging issues encountered by INMI during the 2014-2015 EVD outbreak in terms of preparedness and response to the epidemiological, clinical, diagnostic and research controversial aspects of EVD, both in Italy and in the field.

Zika virus (ZIKV) is mainly transmitted by mosquitoes bites. However, transmission by sexual contacts has been reported in 11 non endemic countries. The rapid spread of ZIKV in Latin American and Caribbean Countries (LCR), person-to-person transmission and perceived risk on people's well being can affect the emerging economies of LCR which historically dependent on truism. Here we present an analysis on economic outputs for assessing the current impact of ZIKV on markets. Our analysis show an unexpected resilience of LCR markets to international alerts. This positive response represents an opportunity to scale-up interventions for preventing the further spreading of the ZIKV epidemic.

Background: In the current Ebola epidemic in Western Africa, many healthcare workers have become infected. Some of these have been medically evacuated to hospitals in Europe and the USA. These clinical experiences provide unique insights into the course of Ebola virus disease under optimized condition within high level isolation units., Case Presentation: A 50-year-old Caucasian male physician contracted Ebola virus diseases in Sierra Leone and was medically evacuated to Italy. Few days after the admission the course of the illness was characterized by severe gastro-intestinal symptoms followed by respiratory failure, accompanied by pulmonary infiltration and high Ebola viral load in the bronchial aspirate and Plasmodium vivax co-infection. The patient received experimental antiviral therapy with favipiravir, convalescent plasma and ZMAb. Ebola viral load started to steadily decrease in the blood after ZMAb administration and became undetectable by day 19 after admission, while it persisted longer in urine samples. No temporal association was observed between viral load decay in plasma and administration of favipiravir. The patient completely recovered and was discharged 39 days after admission., Conclusions: This is the first case of Ebola-related interstitial pneumonia documented by molecular testing of lung fluid specimens. This reports underlines the pivotal role of fluid replacement and advanced life support with mechanical ventilation in the management of patients with Ebola virus diseases respiratory failure. Beside our finding indicates a close temporal association between administration of cZMAb and Ebola virus clearance from blood.

Tuberculosis (TB) is still the principal cause of death caused by a single infectious agent, and the balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. The aim of this work was to study the role of myeloid-derived suppressor cells (MDSCs) during active pulmonary tuberculosis at the site of infection. We observed an expansion of MDSCs in the lung and blood of patients with active TB, which are correlated with an enhanced amount of nitric oxide in the plasma. We also found that these cells have the remarkable ability to suppress T-cell response, suggesting an important role in the modulation of the immune response against TB. Interestingly, a trend in the diminution of MDSCs was found after an efficacious anti-TB therapy, suggesting that these cells may be used as a potential biomarker for monitoring anti-TB therapy efficacy.

Background: In Italy the proportion of cases of tuberculosis in persons originating from high-prevalence countries has been increasing in the last decade. We designed a study to assess adherence to and yield of a tuberculosis screening programme based on symptom screening conducted at primary care centres for regular and irregular immigrants and refugees/asylum seekers., Methods: Presence of symptoms suggestive of active tuberculosis was investigated by verbal screening in migrants presenting for any medical condition to 3 free primary care centres in the province of Rome. Individuals reporting at least one symptom were referred to a tuberculosis clinic for diagnostic workup., Results: Among 2142 migrants enrolled, 254 (11.9%) reported at least one symptom suggestive of active tuberculosis and 176 were referred to the tuberculosis clinic. Of them, 80 (45.4%) did not present for diagnostic evaluation. Tuberculosis was diagnosed in 7 individuals representing 0.33% of those screened and 7.3% of those evaluated for tuberculosis., Conclusion: The overall yield of this intervention was in the range reported for other tuberculosis screening programmes for migrants, although we recorded an unsatisfactory adherence to diagnostic workup. Possible advantages of this intervention include low cost and reduced burden of medical procedures for the screened population. Further evaluation of this approach appears to be warranted.

The authors show the results of an integrated model for risk management of tuberculosis in a sample of sheltered homeless in Rome. Tuberculin skin test (TST) was used for evaluating the prevalence of latent infection (LTBI). In TST positives, expectorate was collected and chest X-ray was achieved. Multiple logistic regression analysis was performed to investigate determinants of infection. Out of 288 recruited subjects, 259 returned for the TST reading; 45.56% were positive and referred to a specialized center; 70 accessed the health facility and completed the clinical pathway. The risk factors associated to LTBI were male gender (OR = 3.72), age over 60 years (OR = 3.59), immigrant status (OR = 3.73), and obesity (OR = 2.19). This approach, based on an integrated social network, guarantees high adherence to screening (89.93%), allowing patients testing positive for latent tuberculosis infection to be diagnosed and rapidly referred to a specialized center.

Background: Computer Tomography (CT) is considered the gold standard for assessing the morphological changes of lung parenchyma. Although novel CT techniques have substantially decreased the radiation dose, radiation exposure is still high. Magnetic Resonance Imaging (MRI) has been established as a radiation- free alternative to CT for several lung diseases, but its role in infectious diseases still needs to be explored further. Therefore, the purpose of our study was to compare MRI with high resolution CT (HRCT) for assessing pulmonary tuberculosis., Methods: 50 patients with culture-proven pulmonary tuberculosis underwent chest HRCT as the standard of reference and were evaluated by MRI within 24 h after HRCT. Altogether we performed 60 CT and MRI examinations, because 10 patients were also examined by CT and MRI at follow- up. Pulmonary abnormalities, their characteristics, location and distribution were analyzed by two readers who were blinded to the HRCT results., Results: Artifacts did not interfere with the diagnostic value of MRI. Both HRCT and MRI correctly diagnosed pulmonary tuberculosis and identified pulmonary abnormalities in all patients. There were no significant differences between the two techniques in terms of identifying the location and distribution of the lung lesions, though the higher resolution of MRI did allow for better identification of parenchymal dishomogeneity, caseosis, and pleural or nodal involvement., Conclusion: Technical developments and the refinement of pulse sequences have improved the quality and speed of MRI. Our data indicate that in terms of identifying lung lesions in non-AIDS patients with non- miliary pulmonary tuberculosis, MRI achieves diagnostic performances comparable to those obtained by HRCT but with better and more rapid identification of pulmonary tissue abnormalities due to the excellent contrast resolution.

Background: The first influenza pandemic of the 21th century was ignited by a new strain of influenza A virus (A/H1N1pdm). Specific patient groups, including those with comorbidities, pregnant women, young children, older and immunocompromised patients, are at increased risk for serious influenza-related disease. This study was aimed at investigating the influence of clinical presentation, antiviral treatment and possible drug resistance-associated mutations, on the extent and duration of viral shedding in patients infected with A/H1N1pdm., Methods: An observational study was performed, based on retrospective review of clinical and laboratory records of patients who were hospitalized for A/H1N1pdm infection at the National Institute for Infectious Diseases "L. Spallanzani", Rome, Italy, between April 24 and December 31, 2009. Among 119 hospitalized patients, 39 were selected for a post hoc analysis, based on the availability of serial nasopharyngeal swabs samples and related information., Results: Eleven out of the 39 study patients (28.2%) presented with pneumonia; 29 (74.4%) received antiviral treatment. Patients with pneumonia were significantly older than patients without pneumonia. The mean values of viral RNA concentration were not significantly increased in patients with pneumonia, but a significant increase in the duration of viral shedding was observed as compared to patients without pneumonia. In patients receiving antivirals, the viral RNA concentration was significantly reduced in comparison to untreated patients at days 4-5 after symptom onset, while the overall duration of viral shedding was only marginally affected. A significant correlation between duration of viral shedding and time elapsed between symptom onset and therapy start was observed, with a significant reduction of days of viral shedding when therapy was initiated within 2 days of symptoms appearance. No known drug resistance mutations were detected in patients with prolonged viral shedding., Conclusions: Our results show that severe respiratory illness is associated with delayed virus clearance in patients with A/H1N1pdm infection. Antivirals caused an early reduction of viral load, but only marginally affected the overall duration of shedding. Prolonged shedding was not associated with the emergence of strains carrying known drug-resistance mutations.

Introduction: The influenza virus infection may be severe in non-immune people. Common complications of influenza virus include upper and lower respiratory tract infections, otitis media, myocarditis, acute respiratory distress syndrome and multi-organ failure. There have been cases of vasculitis following influenza vaccination, and rash and acute purpura may occur in certain viral infections. To the best of our knowledge, there are no reports concerning cases of systemic vasculitis associated with pandemic 2009 (H1N1) infection., Case Presentation: A 23-year-old Caucasian woman was hospitalized at the "L. Spallanzani" National Institute for Infectious Diseases in Rome, Italy. Clinical and radiological features including laboratory findings of this case are illustrated. Notably, the patient had fever, severe abdominal pain, hematuria, arthritis, and purpuric manifestations associated with a normal platelet count. Nasopharyngeal and rectal swabs revealed pandemic 2009 (H1N1) virus by reverse-transcriptase-polymerase-chain-reaction assay. Routine laboratory analyses showed elevated inflammatory parameters. The autoimmune panel tests were normal. Steroid therapy associated with oseltamivir achieved an evident and rapid improvement. On day seven the patient chose to leave the hospital against medical advice., Conclusion: Complications related to influenza infection can be life threatening, particularly in immunocompromised patients. Henoch-Schönlein purpura triggered by the novel influenza virus infection could be an attractive pathogenetic hypothesis. We have discussed both the diagnosis and the challenge of therapy protocols. Steroid therapy is part of the management of severe vasculitis. Our case suggests that steroid therapy associated with antivirals can prevent the risk of further complications such as hemorrhage and multi-organ failure during severe vasculitis, without enhancing the virulence of the influenza virus. The possible role of pandemic 2009 (H1N1) in the pathogenesis of hemorrhagic manifestations should be further investigated.

Background: A challenge in tuberculosis (TB) research is to develop a new immunological test that can help distinguish, among subjects responsive to QuantiFERON TB Gold In tube (QFT-IT), those who are able to control Mtb replication (remote LTBI, recent infection and past TB) from those who cannot (active TB disease). IFN-γ response to the Heparin-binding-hemagglutinin (HBHA) of Mtb has been associated with LTBI, but the cumbersome procedures of purifying the methylated and immunological active form of the protein from Mtb or M. bovis Bacillus Calmette et Guerin (BCG) have prevented its implementation in a diagnostic test. Therefore, the aim of the present study was to evaluate the IFN-γ response to methylated HBHA of Mtb produced in M. smegmatis (rHBHAms) in individuals at different stages of TB who scored positive to QFT-IT., Methodology/principal Findings: 87 individuals at different stages of TB who scored positive to QFT-IT were selected. IFN-γ response to in vitro whole blood stimulation with rHBHAms was evaluated by short-term and long-term tests and detected by ELISA or flow cytometry. We demonstrated that the IFN-γ response to rHBHAms is mediated by CD4(+) T-cells with an effector-memory phenotype. This response, evaluated by short-term-tests, is significantly lower in active TB than in remote LTBI (p = 0.0010) and past TB (p = 0.0152). These results were confirmed by long-term tests. The qualitative data confirmed that IFN-γ responses higher than the cut-off point identified by ROC analysis are associated with the status of non-active disease., Conclusions: In this study we show that the T-cell response to a recombinant and methylated HBHA of Mtb produced in M. smegmatis is useful to discriminate between active and non-active TB disease among those responsive to QFT-IT in a whole blood system. Further studies are needed to improve the accuracy of the assay.

Rationale: Due to the invasive nature of the procedures involved, most studies of Mycobacterium tuberculosis (Mtb)-specific immunity in humans have focused on the periphery rather than the site of active infection, the lung. Recently, antigens associated with Mtb-latency and -dormancy have been described using peripheral blood (PB) cells; however their response in the lung is unknown. The objective of this report was to evaluate, in patients prospectively enrolled with suspected active tuberculosis (TB), whether the latency antigen Rv2628 induces local-specific immune response in bronchoalveolar lavage (BAL) cells compared to PB cells., Material/methods: Among the 41 subjects enrolled, 20 resulted with active TB. Among the 21 without active disease, 9 were defined as subjects with latent TB-infection (LTBI) [Quantiferon TB Gold In-tube positive]. Cytokine responses to Rv2628 were evaluated by enzyme linked immunospot (ELISPOT) assay and flow cytometric (FACS) analysis. RD1-secreted antigen stimulation was used as control., Results: There was a significantly higher frequency of Rv2628- and RD1-specific CD4+ T-cells in the BAL of active TB patients than in PB. However the trend of the response to Rv2628 in subjects with LTBI was higher than in active TB in both PB and BAL, although this difference was not significant. In active TB, Rv2628 and RD1 induced a cytokine-response profile mainly consisting of interferon (IFN)-γ-single-positive over double-IFN-γ/interleukin (IL)-2 T-cells in both PB and BAL. Finally, BAL-specific CD4+ T-cells were mostly effector memory (EM), while peripheral T-cell phenotypes were distributed among naïve, central memory and terminally differentiated effector memory T-cells., Conclusions: In this observational study, we show that there is a high frequency of specific T-cells for Mtb-latency and RD1-secreted antigens (mostly IFN-γ-single-positive specific T-cells with an EM phenotype) in the BAL of active TB patients. These data may be important for better understanding the pathogenesis of TB in the lung.

Background: Blood cytokines and chemokines have been proposed as biomarkers for tuberculosis (TB). Recently, some immune mediators found in the urine of patients with renal dysfunctions have also been suggested as potential biomarkers. Finding biomarkers for TB in urine would present several advantages over blood in terms of collection and safety. The objective of this study was to investigate the presence of cytokines and chemokines in the urine of patients with pulmonary TB at the time of diagnosis. In a subgroup, the evaluation was also performed during TB treatment and at therapy completion. Patients with lung diseases other than TB, and healthy subjects were also enrolled., Methods: Urine samples from 138 individuals, after exclusion of renal dysfunctions, were collected during an 18 month-period. Among them, 58 received a diagnosis of pulmonary TB, 28 resulted having lung diseases other than TB, and 34 were healthy subjects. Moreover, 18 TB patients, 9 of whom were tested 2 months after AFB smear sputum reversion and 9 of whom were cured of TB were also included. Cytokines and chemokines in urine were evaluated using a Cytometric-Bead-Array-Flex-Set. IP-10 detection in 49 subjects was also carried out in parallel by using an Enzyme Linked ImmunoSorbent Assay (ELISA)., Results: IFN-γ, TNF-α, IL-2, IL-8, MIP-1α, MIP-1β and RANTES were poorly detected in all urine samples. Conversely, IP-10 was consistently detected in urine and its level was significantly increased in patients with lung disease compared to healthy subjects (p < 0.001). Increased IP-10 levels were found in both pulmonary TB and lung diseases other than TB. Moreover lower IP-10 levels were found in cured-TB patients compared to the levels at the time of diagnosis, and this difference was close to significance (p = 0.06). Interestingly, we demonstrated a significant correlation between the data obtained by flow cytometry and ELISA (r² 0.82, p < 0.0001)., Conclusions: IP-10, in contrast to IFN-γ, TNF-α, IL-2, IL-8, MIP-1α, MIP-1β and RANTES, is detectable in the urine of patients with pulmonary diseases in the absence of renal dysfunctions. Moreover, the IP-10 level in cured-TB patients is comparable to that found in healthy subjects. More studies are needed to further investigate the clinical utility of these findings.

Background: Bacterial brain abscesses remain a serious central nervous system problem despite advances in neurosurgical, neuroimaging, and microbiological techniques and the availability of new antibiotics. The successful treatment of brain abscesses requires surgery, appropriate antibiotic therapy, and eradication of the primary source; nevertheless many controversial issues on the management of this serious infection remain unresolved., Controversial Issues: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues were: (1) Which patients with bacterial brain abscesses can be managed safely using medical treatment alone? (1a) What is the efficacy in terms of outcome, tolerability, cost/efficacy, and quality of life of the different antibiotic regimens used to treat bacterial cerebral abscesses? (1b) Which antibiotics have the best pharmacokinetics and/or tissue penetration of brain and/or brain abscess? 2) What is the best surgical approach in terms of outcome in managing bacterial brain abscesses? Results are presented and discussed in detail., Methods: A systematic literature search using the MEDLINE database for the period 1988 to 2008 of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence and strength of recommendation was applied., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Over the last decade, methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged as serious pathogens in the nosocomial and community setting. Hospitalization costs associated with MRSA infections are substantially greater than those associated with methicillin-sensitive S. aureus (MSSA) infections, and MRSA has wider economic effects that involve indirect costs to the patient and to society. In addition, there is some evidence suggesting that MRSA infections increase morbidity and the risk of mortality. Glycopeptides are the backbone antibiotics for the treatment of MRSA infections. However, several recent reports have highlighted the limitations of vancomycin, and its role in the management of serious infections is now being reconsidered. Several new antimicrobials demonstrate in vitro activity against MRSA and other Gram-positive bacteria. Data from large surveys indicate that linezolid, daptomycin, and tigecycline are almost universally active against MRSA. This review will briefly discuss the epidemiology, costs, outcome, and therapeutic options for the management of MRSA infections., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: The treatment of severe bloodstream infections (sepsis, endocarditis, and infections of vascular prostheses) caused by Gram-positive microorganisms is made even more difficult by the emergence of resistant strains. The introduction of new antibiotics with activity against these strains has created new opportunities, but many controversial issues remain., Controversial Issues: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues concerned the duration of therapy and role of aminoglycosides and teicoplanin in the treatment of Gram-positive bacterial endocarditis, the optimal use of the new antibiotics in the treatment of bloodstream infections caused by resistant Gram-positive strains, and the use of microbiological techniques (i.e., bactericidal serum testing and synergy testing) and of pharmacokinetic data (e.g., monitoring of plasma levels of antibiotics) in the treatment of difficult-to-treat Gram-positive bloodstream infections., Methods: A systematic literature search of randomized controlled trials and/or non-randomized studies was performed mainly using the MEDLINE database. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for non-randomized studies. The GRADE method for grading the quality of evidence and strength of recommendation was applied., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Complicated skin and skin-structure infections (cSSSI), including surgical site infections (SSI), cellulitis, and abscesses, have been extensively studied, but controversial issues still exist., Controversial Issues: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for the following controversial issues: (1) What is the efficacy of topical negative pressure wound treatment as compared to standard of care in the treatment of severe surgical site infections, i.e., deep infections, caused by Gram-positive microorganisms? (2) Which are the most effective antibiotic therapies in the treatment of cSSSI, including SSI, due to methicillin-resistant staphylococci? Results are presented and discussed., Methods: A systematic literature search using the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and www.clinicaltrials.gov databases of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method was used for grading quality of evidence. An analysis of the studies published between 1990 and 2008 is presented and discussed in detail., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Hospital-associated pneumonia (HAP) remains an important cause of morbidity and mortality despite advances in antimicrobial therapy. Many aspects of the treatment of HAP caused by multi-resistant Gram-positive microorganisms have been extensively studied, but controversial issues remain., Controversial Issues: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues were: (1) Is combination antibiotic therapy or monotherapy more effective in the treatment of HAP? (2) What role do pharmacokinetic/pharmacodynamic antibiotic features have as a guide in the selection of treatment for HAP? (3) Is a de-escalation approach for the management of HAP effective? An analysis of the studies published up until April 2009 is presented and discussed in detail., Methods: A systematic literature search using PubMed, MEDLINE, and EMBASE databases and the Cochrane Library was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence was applied., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Five thematic working groups composed of Italian infectious disease experts and a group coordinator, supported by a scientific secretary, identified controversial issues in the field of severe healthcare-associated infections caused by multidrug-resistant organisms. The five group coordinators received training courses on data sources and electronic databases, literature search strategies, the scientific revision methods of quality assessment, and the construction of an evidence matrix., Working Plan and Methods: The working plan identified the following step: definition of the controversial issues and identification of documents for a systematic literature review. A specific methodology to classify the selected evidence was used that required the evaluation of the quality of review documents and statement documents and evaluation of the quality of original research. An original method to assess review documents and statement documents was proposed. A matrix model to extract and evaluate the evidence from original studies was designed using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, cohorts, and retrospective studies., Quality of Evidence: A modified GRADE working group method was applied for grading quality of evidence and strength of recommendations. The working groups reviewed the available studies and formulated recommendations to be voted on at the national consensus conference held in Rome in June 2009., (Copyright © 2010. Published by Elsevier Ltd.)

Background: Joint replacement surgery has been on the increase in recent decades and prosthesis infection remains the most critical complication. Many aspects of the primary prevention and clinical management of such prosthesis infections still need to be clarified., Controversial Issues: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for the following controversial issues: (1) Is a conservative surgical approach for the management of prosthetic joint infections effective? (2) Is the one-stage or the two-stage revision for the management of prosthetic joint infections more effective? (3) What is the most effective treatment for the management of prosthetic joint infections due to methicillin-resistant staphylococci? Results are presented and discussed in detail., Methods: A systematic literature search using the MEDLINE database for the period 1988 to 2008 of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence and strength of recommendation was applied., (Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Molecular testing of 270 consecutive nasopharyngeal swab samples taken in May and June 2009 and 274 samples from patients hospitalized between July and December 2009 showed similar findings of respiratory viruses, with influenza A pandemic virus H1N1/09 being the most represented, followed by human parainfluenza virus type 3 and rhinoviruses. Statistical analyses suggested virus cocirculation in the absence of viral interference.

Background: Pandemic A/H1N1v influenza is characterized by a mild clinical course. However, a small subset of patients develops a rapidly progressive course caused by primary viral pneumonia or secondary bacterial infections that, in many cases, lead to death due to respiratory failure. The aim of the present study was to analyze the involvement of the immune response in the clinical presentation of H1N1v influenza., Methods: The differentiation and functional capability of T cells from H1N1v-infected patients presenting with either mild disease (n=22) or severe or fatal disease (n=6) were compared. Moreover, plasma cytokines and chemokines were quantified., Results: T cells from H1N1v-infected patients presenting with a severe clinical course resulted in impaired effector cell differentiation and failed to respond to mitogenic stimulation. T cell anergy was strictly associated with a severe acute phase of infection, but T cells could be restored in patients able to recover. Of interest, massive expression of CD95 marker was found on anergic T cells, suggesting an apoptosis-related mechanism. Finally, lower plasma levels of interferon-alpha and monocyte chemoattractant protein-1 were found in patients with a worse clinical course of influenza, suggesting impaired production of these cytokines., Conclusions: Our results show a strict association between host immune competence and the severity of the clinical course of H1N1v infection. By monitoring host functional response, patients with an enhanced risk of developing influenza-associated severe complications could be identified in a timely manner.

Interferon-gamma release assays based on region of difference 1 antigens have improved diagnosis of latent tuberculosis infection (LTBI). However, these tests cannot discriminate between recently acquired infection (higher risk of progression to active tuberculosis) and remote LTBI. The objective of the present study was to evaluate the T-cell interferon-gamma responses to Mycobacterium tuberculosis DosR-regulon-encoded antigens (latency antigens) compared with QuantiFERON TB-Gold In-Tube (QFT-GIT) in subjects at different stages of tuberculosis. A total of 16 individuals with remote LTBI and 23 with recent infection were studied; 15 controls unexposed to M. tuberculosis and 50 patients with active tuberculosis and 45 with cured tuberculosis were also analysed. The results indicated that subjects with remote LTBI showed significantly higher whole-blood interferon-gamma responses to M. tuberculosis latency antigen Rv2628 than did individuals with recent infection, active tuberculosis and controls (p<0.003), whereas no significant differences between these groups were found for other latency antigens tested (Rv2626c, Rv2627c, Rv2031c and Rv2032). The proportion of responders to Rv2628 was five-fold higher among QFT-GIT-positive-individuals with remote infection than among those with recently acquired infection. These data suggest that responses to M. tuberculosis latency antigen Rv2628 may associate with immune-mediated protection against tuberculosis. In contact-tracing investigations, these preliminary data may differentiate recent (positive QFT-GIT results without responses to Rv2628) from remote infection (positive to both tests).

Therapeutic drug monitoring allows to determine the best dosage regimen adapted to each patient optimizing the therapeutic benefits, while minimizing the risk for side effects. Here, the first methodological approach based on matrix-assisted laser desorption/ionization source equipped with tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry for the determination of the antituberculosis (anti-TB) drugs ethambutol, pyrazinamide, rifampicin, and streptomycin concentration in the plasma of tuberculosis-infected patients is reported. The volume of the plasma sample was 200 microL. Plasma samples were cleaned-up by protein precipitation and evaporated in a water bath under a nitrogen stream. The extracted samples were reconstituted with 200 microL of 50% methanol-0.03% formic acid solution (v/v), spiked with known amounts of anti-TB drugs, mixed (1:1) with a saturated matrix solution (4-hydroxybenzoic acid in 50% acetonitrile-0.1% trifluoracetic acid solution; v/v), and spotted onto the MALDI-TOF/TOF sample target plate. The anti-TB drug concentration was determined by standard additions analysis. Regression of standard additions was linear over the whole anti-TB drug concentration range explored (the final anti-TB drug concentration ranged from 0.20 to 200 pmol/microL). The absolute recovery of the anti-TB drugs ranged between 87 and 110%. The minimal ethambutol, pyrazinamide, rifampicin, and streptomycin concentration detectable by MALDI-TOF/TOF is 0.08, 0.20, 0.12, and 0.15 pmol/microL, respectively.

Background: Diffuse alveolar haemorrhage (DAH) has been rarely reported in association with pulmonary infections., Case Presentation: We report the case of a 43 year old immunocompetent man presenting with dyspnoea, fever and haemoptysis. Chest imaging showed bilateral ground glass opacities. Microbiological and molecular tests were positive for Mycobacterium tuberculosis and treatment with isoniazid, rifampicin, ethambutol and pyrazinamide was successful. In this case the diagnosis of DAH relies on clinical, radiological and endoscopic findings. Routine blood tests documented the presence of anticardiolipin antibodies. In the reported case the diagnostic criteria of antiphospholipid syndrome were not fulfilled., Conclusions: The transient presence of anticardiolipin antibodies in association with an unusual clinical presentation of pulmonary tuberculosis is intriguing although a causal relationship cannot be established.

In October 2009, a traveller returning from Africa to Italy was hospitalised with symptoms suggestive of a haemorrhagic fever of unknown origin. The patient was immediately placed in a special biocontainment unit until laboratory investigations confirmed the infection to be caused by a dengue serotype 3 virus. This case reasserts the importance of returning travellers as sentinels of unknown outbreaks occurring in other countries, and highlights how the initial symptoms of dengue fever resemble those of other haemorrhagic fevers, hence the importance of prompt isolation of patients until a final diagnosis is reached.

Background: Interferon-gamma (IFN-gamma) release assays (IGRAs) were designed to detect latent tuberculosis infection (LTBI). However, discrepancies were found between the tuberculin skin test (TST) and IGRAs results that cannot be attributed to prior Bacille Calmètte Guerin vaccinations. The aim of this study was to evaluate tools for improving LTBI diagnosis by analyzing the IFN-gamma response to RD1 proteins in prolonged (long-term response) whole blood tests in those subjects resulting negative to assays such as QuantiFERON-TB Gold In tube (QFT-IT)., Methods: The study population included 106 healthy TST+ individuals with suspected LTBI (recent contact of smear-positive TB and homeless) consecutively enrolled. As controls, 13 healthy subjects unexposed to M. tuberculosis (TST-, QFT-IT-) and 29 subjects with cured pulmonary TB were enrolled. IFN-gamma whole blood response to RD1 proteins and QFT-IT were evaluated at day 1 post-culture. A prolonged test evaluating long-term IFN-gamma response (7-day) to RD1 proteins in diluted whole blood was performed., Results: Among the enrolled TST+ subjects with suspected LTBI, 70/106 (66.0%) responded to QFT-IT and 64/106 (60.3%) to RD1 proteins at day 1. To evaluate whether a prolonged test could improve the detection of LTBI, we set up the test using cured TB patients (with a microbiologically diagnosed past pulmonary disease) who resulted QFT-IT-negative and healthy controls as comparator groups. Using this assay, a statistically significant difference was found between IFN-gamma levels in cured TB patients compared to healthy controls (p < 0.006). Based on these data, we constructed a receiver operating characteristic (ROC) curve and we calculated a cut-off. Based on the cut-off value, we found that among the 36 enrolled TST+ subjects with suspected LTBI not responding to QFT-IT, a long term response to RD1 proteins was detected in 11 subjects (30.6%)., Conclusion: These results indicate that IFN-gamma long-term response to M. tuberculosis RD1 antigens may be used to detect past infection with M. tuberculosis and may help to identify additional individuals with LTBI who resulted negative in the short-term tests. These data may provide useful information for improving immunodiagnostic tests for tuberculosis infection, especially in individuals at high risk for active TB.

Viral haemorrhagic fevers (VHFs) represent a challenge for public health because of their epidemic potential, and their possible use as bioterrorism agents poses particular concern. In 1999 the World Health Organization (WHO) proposed a case definition for VHFs, subsequently adopted by other international institutions with the aim of early detection of initial cases/outbreaks in western countries. We applied this case definition to reports of Ebola and Marburg virus infections to estimate its sensitivity to detect cases of the disease. We analyzed clinical descriptions of 795 reported cases of Ebola haemorrhagic fever: only 58.5% of patients met the proposed case definition. A similar figure was obtained reviewing 169 cases of Marburg diseases, of which only 64.5% were in accordance with the case definition. In conclusion, the WHO case definition for hemorrhagic fevers is too specific and has poor sensitivity both for case finding during Ebola or Marburg outbreaks, and for early detection of suspected cases in western countries. It can lead to a hazardous number of false negatives and its use should be discouraged for early detection of cases.

Background: Hepatitis B outbreaks in healthcare settings are still a serious public health concern in high-income countries. To elucidate the most frequent infection pathways and clinical settings involved, we performed a systematic review of hepatitis B virus outbreaks published between 1992 and 2007 within the EU and USA., Methods: The research was performed using two different databases: the PubMed Database and the Outbreak Database, the worldwide database for nosocomial outbreaks. Selection of papers was carried out using the Quorom algorithm, and to avoid selection biases, the inclusion criteria were established before the articles were identified., Results: Overall, 30 papers were analyzed, reporting on 33 hepatitis B virus outbreaks that involved 471 patients, with 16 fatal cases. Dialysis units accounted for 30.3% of outbreaks followed by medical wards (21.2%), nursing homes (21.2%), surgery wards (15.2), and outpatient clinics (12.1%). The transmission pathways were: multi-vial drugs (30.3%), non-disposable multi-patient capillary blood sampling devices (27.2%), transvenous endomyocardial biopsy procedures (9.1%), and multiple deficiencies in applying standard precautions (9.1%)., Conclusion: The analysis of transmission pathways showed that some breaches in infection control measures, such as administration of drugs using multi-vial compounds and capillary blood sampling, are the most frequent routes for patient-to-patient transmission of hepatitis B virus. Moreover some outbreak reports underlined that heart-transplant recipients are at risk of contracting hepatitis B virus infection during the transvenous endomyocardial biopsy procedure through indirect contact with infected blood as a result of environmental contamination. To prevent transmission, healthcare workers must adhere to standard precautions and follow fundamental infection control principles, such as the use of sterile, single-use, disposable needles and avoiding the use of multi-vial compounds in all healthcare settings including outpatient settings.

Background: Five known human coronaviruses infect the human respiratory tract: HCoV-OC43, HCoV-229E, SARS-CoV, HCoV-NL63 and HCoV-HKU1., Objectives: To evaluate the prevalence of HCoV-NL63 in hospitalized adult patients and to perform molecular characterization of Italian strains., Study Design: HCoV-NL63 was sought by RT-PCR in 510 consecutive lower respiratory tract (LRT) samples, collected from 433 Central-Southern Italy patients over a 1-year period. Phylogenetic analysis was performed by partial sequencing of S and ORF1a. Additional S sequences from Northern Italy were included in the phylogenetic trees., Results: HCoV-NL63 was detected in 10 patients (2.0%) with symptomatic respiratory diseases, mainly during winter. Phylogenetic analysis indicated a certain degree of heterogeneity in Italian isolates. The ORF1a gene clustering in phylogenetic trees did not match with that of the S gene., Conclusions: As observed by others, HCoV-NL63 is often associated with another virus. Phylogenetic characterization of HCoV-NL63 circulating in Italy indicates that this virus circulates as a mixture of variant strains, as observed in other countries.

No information is currently available on the influence of injectable second-line drugs on treatment outcomes of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) patients. To investigate this issue, a large series of MDR- and XDR-TB cases diagnosed in Estonia, Germany, Italy and the Russian Federation (Archangels Oblast) between 1999 and 2006 were analysed. All study sites performed drug susceptibility testing for first- and second-line anti-TB drugs, laboratory quality assurance and treatment delivery according to World Health Organization recommendations. Out of 4,583 culture-confirmed cases, 240 MDR- and 48 XDR-TB cases had a definitive outcome recorded (treatment success, death, failure). Among MDR- and XDR-TB cases, capreomycin resistance yielded a higher proportion of failure and death than capreomycin-susceptible cases. Resistance to capreomycin was independently associated with unfavourable outcome (logistic regression analysis: odds ratio 3.51). In the treatment of patients with multidrug-resistant and extensively drug-resistant tuberculosis, resistance to the injectable drug capreomycin was an independent predictor for therapy failure in this cohort. As Mycobacterium tuberculosis drug resistance is increasing worldwide, there is an urgent need for novel interventions in the fight against tuberculosis.

Background: Respiratory infections are the most common infections in humans. The prevalence of respiratory viruses in adults is largely underestimated, and relevant data mostly concern infants and children., Objectives: To evaluate the prevalence of respiratory viruses in adults hospitalized in Italy., Study Design: During April 2004--May 2005, 510 consecutive lower respiratory tract samples were prospectively collected. These were evaluated with a molecular panel that detected 12 respiratory viruses., Results: Two hundred and fifteen samples were positive for at least one viral pathogen, with an overall sample prevalence of 42.2%. Human rhinoviruses (HRVs) were the most commonly detected viruses (32.9%), followed by influenza virus (FLU)-A (9.0%); the other viruses were 2% or less. Multiple agents were detected in 30 samples from 29 patients, resulting in a co-infection rate of 6.7%., Conclusions: This study shows a high prevalence of viruses in the lower respiratory tract samples of hospitalized adults, mostly HRV and FLU-A. It is not possible to establish the role of viruses detected at low frequency, but our findings suggest the necessity to consider them as potential causes or precursors of lower respiratory tract infections (LRTIs).