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Background Invasive aspergillosis (IA) by a triazole-resistant Aspergillus fumigatus is associated with high mortality. Real-time resistance detection will result in earlier initiation of appropriate therapy. Methods In a prospective study, we evaluated the clinical value of the AsperGenius polymerase chain reaction (PCR) assay in hematology patients from 12 centers. This PCR assay detects the most frequent cyp51A mutations in A. fumigatus conferring azole resistance. Patients were included when a computed tomography scan showed a pulmonary infiltrate and bronchoalveolar fluid (BALf) sampling was performed. The primary end point was antifungal treatment failure in patients with azole-resistant IA. Results Of 323 patients enrolled, complete mycological and radiological information was available for 276 (94%), and probable IA was diagnosed in 99/276 (36%). Sufficient BALf for PCR testing was available for 293/323 (91%). Aspergillus DNA was detected in 116/293 (40%) and A. fumigatus DNA in 89/293 (30%). The resistance PCR was conclusive in 58/89 (65%) and resistance detected in 8/58 (14%). Two had a mixed azole-susceptible/azole-resistant infection. In the 6 remaining patients, treatment failure was observed in 1. Galactomannan positivity was associated with mortality (P = .004) while an isolated positive Aspergillus PCR was not (P = .83). Conclusions Real-time PCR-based resistance testing may help to limit the clinical impact of triazole resistance. In contrast, the clinical impact of an isolated positive Aspergillus PCR on BALf seems limited. The interpretation of the EORTC/MSGERC PCR criterion for BALf may need further specification (eg, minimum cycle threshold value and/or PCR positive on >1 BALf sample).

Background: In many infants, treatment is started for suspicion of early onset sepsis (EOS), of whom the majority do not have an infection. Early prediction of the absence of a culture-proven sepsis (CPS) would significantly reduce the time of antibiotic treatment and hospitalization. Our objective was to analyze 3 criteria in infants with CPS: positive blood culture (BC) at 24 hours after the onset of suspicion of EOS (OSEOS), C-reactive protein (CRP) >= 10 mg/L and clinical signs of infection, so we can consequently consider to stop antibiotic treatment in infants without these criteria.Methods: We included all infants with suspicion of EOS from 2007 until 2020. The proportion was calculated of (1) infants with CPS with, at 24 hours, a positive BC and/or CRP >= 10 mg/L and/or clinical signs of infection and (2) infants without CPS with CRP = 24 hours in 8 (16%) infants, of whom 7 infants had a raised CRP and/or clinical symptoms of infection within 24 hours. In 1095 (74%) of infants without CPS in whom CRP was measured between 12 and 24 hours after OSEOS, CRP was

World-wide, emerging triazole resistance increasingly complicates treatment of invasive aspergillosis (IA). In settings with substantial (>10%) prevalence of triazole resistance, empiric combination therapy with both a triazole and liposomal amphotericin B (LAmB) can be considered because of the low yields of susceptibility testing. To avoid toxicity while optimizing outcome, a strategy with monotherapy would be preferable. A newly designed treatment algorithm based on literature and expert consensus provided guidance for empiric monotherapy with either voriconazole or LAmB. Over a four and a half year period, all adult patients in our hospital treated for IA were included and patient data were collected. An independent committee reviewed the attributability of death to IA for each patient. Primary outcomes were 30- and 100-day crude mortality and attributable mortality. In total, 110 patients were treated according to the treatment algorithm. Fifty-six patients (51%) were initially treated with voriconazole and 54 patients (49%) with LAmB. Combined attributable and contributable mortality was 13% within 30 days and 20% within 100 days. Treatment switch to LAmB was made in 24/56 (43%) of patients who were initially treated with voriconazole. Combined contributable and attributable 100-day mortality in this subgroup was 21% and was not increased when compared with patients initially treated with LAmB (P = 0.38). By applying a comprehensive clinical decision algorithm, an antifungal-sparing regime was successfully introduced. Further research is warranted to explore antifungal treatment strategies that account for triazole-resistance. Lay summary Due to resistance of Aspergillus against triazoles, combination therapy with liposomal amphotericin B (LAmB) is applied more often as primary therapy against invasive aspergillosis. This study presents the results of a decision tool which differentiated between triazole or LAmB monotherapy.

We report two cases of Emergomyces pasteurianus infection in the Netherlands. Both patients were immunocompromised and had pulmonary symptoms. The first patient died due to a pulmonary infection with Es. pasteurianus, concomitant listeriosis, Pseudomonas aeruginosa sepsis and invasive pulmonary aspergillosis. The second patient had pulmonary and subcutaneous lesions, and recovered completely after treatment with posaconazole for 14 months. In both cases, diagnosis of Es. pasteurianus was made with internal transcribed spacer rRNA PCR and culture. Keywords: Emergomyces, Immunocompromised, Mycosis, Disseminated infection, Dimorphic fungi

Contains fulltext : 220210.pdf (Publisher’s version ) (Open Access) We investigated the prevalence of azole resistance of Aspergillus fumigatus isolates in the Netherlands by screening clinical A. fumigatus isolates for azole resistance during 2013-2018. We analyzed azole-resistant isolates phenotypically by in vitro susceptibility testing and for the presence of resistance mutations in the Cyp51A gene. Over the 6-year period, 508 (11%) of 4,496 culture-positive patients harbored an azole-resistant isolate. Resistance frequency increased from 7.6% (95% CI 5.9%-9.8%) in 2013 (58/760 patients) to 14.7% (95% CI 12.3%-17.4%) in 2018 (112/764 patients) (p = 0.0001). TR(34)/L98H (69%) and TR(46)/Y121F/T289A (17%) accounted for 86% of Cyp51A mutations. However, the mean voriconazole MIC of TR(34)/L98H isolates decreased from 8 mg/L (2013) to 2 mg/L (2018), and the voriconazole-resistance frequency was 34% lower in 2018 than in 2013 (p = 0.0001). Our survey showed changing azole phenotypes in TR(34)/L98H isolates, which hampers the use of current PCR-based resistance tests. 01 juli 2020

Aim Nosocomial infections (NI) in neonates are associated with prolonged hospitalisation, adverse neurodevelopmental outcome and high mortality. Over the past decade, numerous prevention strategies have resulted in significant reductions in NI rates. In this review, we aim to provide an overview of current NI rates from large, geographically defined cohorts. Methods PubMed, Web of Science, EMBASE and Cochrane Library were searched for evidence regarding epidemiology and prevention of NI in neonates. Extracted studies were synthesised in a narrative form with experiential reflection. Results Despite the abundance of geographically defined incidence proportions, an epidemiological overview of NI is difficult to provide, given the lack of consensus definition for neonatal NI and different baseline populations being compared. Successful prevention efforts have focused on implementing evidence‐based practices while eliminating outdated strategies. The most promising model for reduction in infection rates is based on quality improvement (QI) collaboratives and benchmarking, involving identification and implementation of best practices, selection of measurable outcomes and fostering a sense of community and transparency. Conclusion The preventative rather than curative approach forms the new paradigm for reducing the burden of neonatal infections. Despite progress achieved, continued work towards improved prevention practices is required in the strive towards zero NIs.

Background Controlled human hookworm infections could significantly contribute to the development of a hookworm vaccine. However, current models are hampered by low and unstable egg output, reducing generalizability and increasing sample sizes. This study aims to investigate the safety, tolerability, and egg output of repeated exposure to hookworm larvae. Methods Twenty-four healthy volunteers were randomized, double-blindly, to 1, 2, or 3 doses of 50 Necator americanus L3 larvae at 2-week intervals. Volunteers were monitored weekly and were treated with albendazole at week 20. Results There was no association between larval dose and number or severity of adverse events. Geometric mean egg loads stabilized at 697, 1668, and 1914 eggs per gram feces for the 1 × 50L3, 2 × 50L3, and 3 × 50L3 group, respectively. Bayesian statistical modeling showed that egg count variability relative to the mean was reduced with a second infectious dose; however, the third dose did not increase egg load or decrease variability. We therefore suggest 2 × 50L3 as an improved challenge dose. Model-based simulations indicates increased frequency of stool sampling optimizes the power of hypothetical vaccine trials. Conclusions Repeated infection with hookworm larvae increased egg counts to levels comparable to the field and reduced relative variability in egg output without aggravating adverse events. Clinical Trials Registration NCT03257072.

Introduction Nosocomial infections (NIs) are a major source of iatrogenic harm in neonatal intensive care units (NICUs). The influence of the infrastructure of NICUs on NIs is not well documented. This study aims to examine the effect of single-room units (SRU) versus open-bay units (OBU) on the incidence of NIs, including central-line-associated bloodstream infections (CLABSI), in preterm neonates. Methods All preterm neonates (

Background Adequate dosage recommendations are imperative for successful treatment of invasive infections. We evaluated the occurrence of sub- and supratherapeutic serum and cerebrospinal fluid (CSF) concentrations of benzylpenicillin (BPEN) in neonates treated for a severe group B streptococci (GBS) sepsis and/or meningitis as well as discrepancies in dosing recommendations provided by pediatric reference sources. Methods Retrospective analysis of (pre)term infants treated with BPEN undergoing therapeutic drug monitoring (TDM) between May 2015 and May 2019. Outcomes included numbers of sub- and supratherapeutic concentrations, and dose adjustments, clinical evolution, and dosing recommendations from six pediatric reference sources. Results A total of 21 TDM samples from 8 neonates were evaluated. Among serum concentrations, 9/21 (43%) were below and 8/21 (38%) above the pre-specified therapeutic target range of 10-20 mg/L. Only 1 patient had BPEN determined in CSF whose concentration was below the lower limit of quantification. TDM identified a need for dose modification in 10/21 (48%) instances. Three of eight patients exhibited complete resolution of clinical, laboratory and radiologic signs of infection. Substantial variation in dosing recommendations (50,000-400,000 IE/kg/d) was present between reference sources. Conclusions Our data reveal that under current dosage recommendations, the predefined target serum or CSF concentrations of BPEN are not achieved in all children. In case of clinical failure, serum and/or CSF BPEN concentrations should be determined. Given the wide variation in concentrations and subsequent dose requirements, further exploration of the clinical and pharmacologic characteristics of BPEN in (pre)term neonates is essential to optimize therapeutic efficacy.

Schistosomiasis treatment relies on the use of a single drug, praziquantel, which is insufficient to control transmission in highly endemic areas1. Novel medicines and vaccines are urgently needed2,3. An experimental human model for schistosomiasis could accelerate the development of these products. We performed a dose-escalating clinical safety trial in 17 volunteers with male Schistosoma mansoni cercariae, which do not produce eggs (clinicaltrials.gov NCT02755324), at the Leiden University Medical Center, the Netherlands. The primary endpoints were adverse events and infectivity. We found a dose-related increase in adverse events related to acute schistosomiasis syndrome, which occurred in 9 of 17 volunteers. Overall, 5 volunteers (all 3 of the high dose group and 2 of 11 of the medium dose group) reported severe adverse events. Worm-derived circulating anodic antigen, the biomarker of the primary infection endpoint, peaked in 82% of volunteers at 3–10 weeks following exposure. All volunteers showed IgM and IgG1 seroconversion and worm-specific cytokine production by CD4+ T cells. All volunteers were cured with praziquantel provided at 12 weeks after exposure. Infection with 20 Schistosoma mansoni cercariae led to severe adverse events in 18% of volunteers and high infection rates. This infection model paves the way for fast-track product development for treatment and prevention of schistosomiasis. A new human challenge model of schistosomiasis, which affects more than 290 million people globally, will aid development of novel therapies and vaccines for this neglected tropical disease.

Patients with haematological malignancies are at risk for invasive fungal diseases (IFD). A survey was conducted in all Dutch academic haematology centres on their current diagnostic, prophylactic and therapeutic approach towards IFD in the context of azole-resistance. In all 8 centres, a haematologist and microbiologist filled in the questionnaire that focused on different subgroups of haematology patients. Fungal prophylaxis during neutropaenia was directed against Candida and consisted of fluconazole and/or amphotericin B suspension. Mould-active prophylaxis was given to acute myeloid leukaemia patients during chemotherapy in 2 of 8 centres. All centres used azole prophylaxis in a subset of patients with graft-versus-host disease. A uniform approach towards the diagnosis and treatment of IFD and in particular azole-resistant Aspergillus fumigatus was lacking. In 2017, all centres agreed to implement a uniform diagnostic and treatment algorithm regarding invasive aspergillosis with a central role for comprehensive diagnostics and PCR-based detection of azole-resistance. This study (DB-MSG 002) will re-evaluate this algorithm when 280 patients have been treated. A heterogeneous approach towards antifungal prophylaxis, diagnosis and treatment was apparent in the Netherlands. Facing triazole-resistance, consensus was reached on the implementation of a uniform diagnostic approach in all 8 centres.

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Four healthy volunteers were infected with 50 Necator americanus infective larvae (L3) in a controlled human hookworm infection trial and followed for 52 weeks. The kinetics of fecal egg counts in volunteers was assessed with Bayesian multilevel analysis, which revealed an increase between weeks 7 and 13, followed by an egg density plateau of about 1000 eggs/g of feces. Variation in egg counts was minimal between same-day measurements but varied considerably between days, particularly during the plateau phase. These analyses pave the way for the controlled human hookworm model to accelerate drug and vaccine efficacy studies.

Contains fulltext : 204852.pdf (Publisher’s version ) (Closed access) BACKGROUND: Triazole resistance is an increasing problem in invasive aspergillosis (IA). Small case series show mortality rates of 50%-100% in patients infected with a triazole-resistant Aspergillus fumigatus, but a direct comparison with triazole-susceptible IA is lacking. METHODS: A 5-year retrospective cohort study (2011-2015) was conducted to compare mortality in patients with voriconazole-susceptible and voriconazole-resistant IA. Aspergillus fumigatus culture-positive patients were investigated to identify patients with proven, probable, and putative IA. Clinical characteristics, day 42 and day 90 mortality, triazole-resistance profiles, and antifungal treatments were investigated. RESULTS: Of 196 patients with IA, 37 (19%) harbored a voriconazole-resistant infection. Hematological malignancy was the underlying disease in 103 (53%) patients, and 154 (79%) patients were started on voriconazole. Compared with voriconazole-susceptible cases, voriconazole resistance was associated with an increase in overall mortality of 21% on day 42 (49% vs 28%; P = .017) and 25% on day 90 (62% vs 37%; P = .0038). In non-intensive care unit patients, a 19% lower survival rate was observed in voriconazole-resistant cases at day 42 (P = .045). The mortality in patients who received appropriate initial voriconazole therapy was 24% compared with 47% in those who received inappropriate therapy (P = .016), despite switching to appropriate antifungal therapy after a median of 10 days. CONCLUSIONS: Voriconazole resistance was associated with an excess overall mortality of 21% at day 42 and 25% at day 90 in patients with IA. A delay in the initiation of appropriate antifungal therapy was associated with increased overall mortality.

A retrospective case record study was conducted that established a scoring tool based on clinical and iQ200 parameters, able to predict or rule out the clinical diagnosis of UTI in the majority of adult patients in an academic hospital. Automated standardized quantitative urine analysis, such as iQ200 analysis, is on the rise because of its high accuracy and efficiency compared to those of traditional urine analysis. Previous research on automated urinalysis focused mainly on predicting culture results but not on the clinical diagnosis of urinary tract infection (UTI). A retrospective analysis was conducted of consecutive urine samples sent in for culture because of suspected UTI. UTI was defined by expert opinion, based on reported symptoms, conventional urine sediment analysis, and urine cultures. Parameters of iQ200 analysis and clinical symptoms and signs were compared between cases and controls. Optimal cutoff values were determined for iQ200 parameters, and multivariate logistic regression analysis was used to identify the set of variables that best predicts the clinical diagnosis of UTI for development of a scoring tool. A total of 382 patients were included. Optimal cutoff values of iQ200 analysis were 74 white blood cells (WBC)/μl, 6,250 “all small particles” (ASP)/μl, and a bacterial score of 2 on an ordinal scale of 0 to 5. The scoring tool attributed 1 point for frequent micturition or increased urge, 2 points for dysuria, 1 point for a bacterial score of ≥2, 2 points for WBC/μl of ≥50, and an additional point for WBC/μl of ≥150. This score had a sensitivity of 86% and a specificity of 92% when using a threshold of

To accelerate the development of novel vaccines for schistosomiasis, we set out to develop a human model for Schistosoma mansoni infection in healthy volunteers. During natural infections, female schistosomes produce eggs that give rise to morbidity. Therefore, we produced single-sex, male Schistosoma mansoni cercariae for human infection without egg production and associated pathology. Cercariae were produced in their intermediate snail hosts in accordance with the principles of good manufacturing practice (GMP). The application of GMP principles to an unconventional production process is a showcase for the controlled production of complex live challenge material in the European Union or under Food and Drug Administration guidance.

Background Triazole resistance in Aspergillus spp. is emerging and complicates prophylaxis and treatment of invasive Aspergillosis (IA) worldwide. New polymerase chain reaction (PCR) tests on broncho-alveolar lavage (BAL) fluid allow for detection of triazole resistance on a genetic level, which opened up new possibilities for targeted therapy. In the absence of clinical trials, a modeling study delivers estimates of the added value of resistance detection with PCR and which empiric therapy would be optimal when local resistance rates are known. Methods We performed a decision-analytic modeling study based on epidemiological data of IA, extended with estimated dynamics of resistance rates and treatment effectiveness. We compared 6 clinical strategies that differ in the use of PCR diagnostics (A: not used, B: used) and in empiric therapeutic choice in case of unknown triazole susceptibility: Voriconazole (1, VOR), Liposomal Amphotericin B (2, LAmB), or both (3). Outcome measures were proportion of correct treatment, survival, and serious adverse events. Results Implementing Aspergillus PCR tests was projected to result in residual treatment susceptibility mismatches of Conclusion Introduction of current Aspergillus PCR tests on BAL-fluid is an effective way to increase the proportion of patients that receive targeted therapy for IA. The results indicate that close monitoring of background resistance rates and of adverse drug events are important to attain the potential benefits of LAmB. The choice of strategy ultimately depends on the probability of triazole resistance, the availability of PCR, and individual patient characteristics. Disclosures All authors: No reported disclosures.

BackgroundBlood cultures are considered the gold standard to distinguish bacteremia from non-bacteremic systemic inflammation. In current clinical practice, bacteraemia is considered unlikely if blood cultures have been negative for 48-72 hours. Modern BC systems have reduced this time-to-positivity (TTP), questioning whether the time frame of 48-72 hrs is still valid. This study investigates the distribution of TTP, the probability of blood culture positivity after 24 hours, and identifies clinical predictors of prolonged TTP.MethodsAdult patients with monomicrobial bacteremia in an academic hospital were included retrospectively over a three-year period. Clinical data were retrieved from the medical records. Predictors of TTP >24 hours were determined by uni- and multivariate analyses. The residual probability of bacteremia was estimated for the scenario of negative BCs at 24 hours after bedside collection.ResultsThe cohort consisted of 801 patients, accounting for 897 episodes of bacteremia. Mean age was 65 years (IQR 54-73), 534 (59.5%) patients were male. Median TTP was 15.7 (IQR 13.5-19.3) hours. TTP was ≤24 hours in 85.3% of episodes. Antibiotic pre-treatment (adjusted OR 1.77; 95%CI 1.14-2.74, pConclusionWith adequate hospital logistics, the probability of positive blood cultures after 24 hours of negative cultures was low. Combined with clinical reassessment, knowledge of this low probability may contribute to prioritization of the differential diagnosis and decisions on antimicrobial therapy. As a potential antibiotic stewardship tool, this strategy warrants further prospective investigation.

As the majority of urine samples submitted for culture yields a negative result, rapid screening that accurately predicts culture outcome benefits clinicians by reducing the time to result and improves the efficiency of the microbiological laboratory. Automated urinalysis using the IRIS Diagnostics iQ200 Elite (iQ200) analyzer permits just such a fast and large-scale screening. We aimed to predict and thus to reduce negative cultures with a screening algorithm based on iQ200 urinalysis in a tertiary university hospital. In parallel, we evaluated the performance of the iQ200 screen compared to that of Gram stain for sample quality. We screened 1,442 samples submitted for bacterial culture using the iQ200 analyzer; of these samples, 357 (24.8%) had a positive culture result. We identified the absence of microorganisms in the iQ200 screen as the strongest solitary predictor for a negative culture, with a sensitivity of 90.5% (323/357). The algorithm was further improved by performing logistic regression on leukocyte counts, which gave a cutoff of 65 leukocytes/μl to obtain the desired sensitivity of >95% (95.2%; 95% confidence interval [CI], 92.5 to 97.0), a negative predictive value of 97.3% (95% CI, 95.7 to 98.3), and an anticipated culture workload reduction of 44% (95% CI, 41 to 46). Concordance between sample quality based on Gram stain and iQ200 screening was only 72%, which was probably a result of interobserver effect in evaluation of the Gram stain. In conclusion, in our setting, screening by iQ200 proved to be a safe and cost-effective means to provide faster culture results, and it has the added benefit of a more objective evaluation of sample quality.

Contains fulltext : 172306.pdf (Publisher’s version ) (Closed access) A survey of diagnosis and treatment of invasive aspergillosis was conducted in eight University Medical Centers (UMCs) and eight non-academic teaching hospitals in the Netherlands. Against a background of emerging azole resistance in Aspergillus fumigatus routine resistance screening of clinical isolates was performed primarily in the UMCs. Azole resistance rates at the hospital level varied between 5% and 10%, although rates up to 30% were reported in high-risk wards. Voriconazole remained first choice for invasive aspergillosis in 13 out of 16 hospitals. In documented azole resistance 14 out of 16 centres treated patients with liposomal amphotericin B.

BACKGROUND Persistent infections with herpesviruses such as human cytomegalovirus (HCMV) frequently occur after solid organ or stem cell transplantation, and are due to either failure of the host to immunologically control the virus or emerging resistance of the virus to the antiviral drug(s) used. Antiviral therapy can be guided by viral drug susceptibility testing based on screening for known resistance-inducing mutations in the viral genome. Mass spectrometry-based comparative sequence analysis (MSCSA) might be advantageous for this purpose because of its suitability for semi-automation. OBJECTIVES The applicability of MSCSA to detect sequence polymorphisms and drug resistance-inducing mutations in the HCMV genome was investigated. STUDY DESIGN We analyzed the 3' part of the HCMV UL97 gene, which encodes the kinase that is activated by the commonly used anti-HCMV drug ganciclovir. Sequences obtained by MSCSA of material from HCMV-infected patients (43 samples) and the HCMV type strain were compared to conventional cycle sequencing results. RESULTS In 94.1% of all samples the results obtained by MSCSA of the UL97 gene were identical to those from conventional cycle sequencing. The threshold to detect mutant sequences in a mixture with wild-type material was 20% using either technique. Furthermore, MSCSA was successfully applied to study the development of drug resistance in a patient who developed encephalitis due to ganciclovir-resistant HCMV. CONCLUSIONS MSCSA was found to be equally accurate compared to conventional cycle sequencing in the analysis of UL97 of HCMV.

Background. Cytomegalovirus (CMV) infections after transplantation are commonly treated using a prophylactic or preemptive regimen with (val)ganciclovir. It remains unclear, which approach is most effective in preventing CMV disease in D+R— patients. The aim of this retrospective study was to compare the treatment response and antiviral resistance in CMV infections between two treatment regimens in D+R— renal transplant recipients. Methods. Before 2006, a preemptive treatment regimen with valganciclovir was applied (42 patients). From 2006 onwards, patients first received prophylaxis with valganciclovir for 90 days, followed by a preemptive regimen (29 patients). CMV infections were monitored by regular determination of the CMV DNA load in plasma. Patient charts were reviewed for antiviral treatment data, and resistance was analyzed by nucleotide sequence analysis of the UL97 and UL54 genes in CMV DNA-positive samples. Results. Treatment failure, defined as a CMV DNA load more than or equal to 1000 copies/mL after at least 2 weeks of treatment, occurred less frequently in the prophylaxis cohort than in the preemptive cohort (14% vs. 71 %, P

Background Varicella zoster virus (VZV) infections are a relevant cause of morbidity and mortality in hematological patients and especially in hematopoietic stem cell transplant (HSCT) recipients. The present study aimed to investigate the prevalence and clinical significance of viral persistence and antiviral resistance by systematically analyzing all episodes of VZV diagnosed in our laboratory in pediatric and adult hematological patients between 2007 and 2010. Methods Patient charts were reviewed to document patient and disease characteristics. VZV loads were determined in all available clinical samples from the day of diagnosis and thereafter. Persistent VZV infection was defined as a VZV infection that lasted at least 7 days. Analysis of resistance was performed in all patients with persistent VZV infection by sequence analysis of viral thymidine kinase and DNA polymerase genes. Results In total, 89 episodes occurred in 87 patients, of whom 65 were recipients of an allogeneic HSCT. Follow-up samples were available in 54 episodes. Persistent VZV was demonstrated in 32 of these episodes (59%). Complications occurred in 16 of the persistent episodes (50%) vs 2 of 22 nonpersistent episodes (9%). Mutations possibly associated with resistance were found in 27% of patients with persistent VZV, including patients with treatment-unresponsive dermatomal zoster that progressed to severe retinal or cerebral infection. Conclusions In hematological patients, VZV-related complications occur frequently, especially in persistent infections. Antiviral resistance is a relevant factor in persistent infections and needs to be investigated in various affected body sites, especially when clinical suspicion of treatment failure arises.

Background Susceptibility testing of herpes simplex virus type 1 (HSV-1) is traditionally performed by a plaque reduction assay (PRA), but this is labor intensive, time consuming and has a manual read out. Objectives The goal of this study was to develop an internally controlled real time PCR-based phenotypical susceptibility test for HSV-1 that is suitable for use in a clinical diagnostic setting. Study design A DNA reduction assay (DRA) was developed and validated on a test panel of 26 well-characterized isolates of varying susceptibility to aciclovir or foscarnet, including low-level resistant isolates. The DRA consisted of pre-culture of a clinical sample for 48 h and subsequent culture in the presence of antivirals for 24 h. Viral DNA concentration in the culture lysates was measured by an internally controlled quantitative real-time HSV-1 PCR and corrected for cell count and lysis by beta-globin PCR. DRA results were compared to results from PRA and sequence analysis. Results DRA results were in accordance with PRA results for both aciclovir and foscarnet susceptibility and appeared to have good discriminative value for low-level resistance due to UL30 gene mutations. Although the direct application of DRA in clinical samples appeared not possible, short pre-culture of 48 h was sufficient and ensured results within a clinically relevant time frame of 5 days. Conclusions DRA is an accurate, rapid and easy to perform phenotypical susceptibility test for HSV-1.

Background Treatment of cytomegalovirus (CMV) infections after stem cell transplantation (SCT) does not always lead to a rapid viral response. The causes of treatment failure may be either viral resistance or immunological failure to control viral replication. This study investigated the response to pre-emptive treatment in CMV infections in order to define risk factors for treatment failure, including the role of antiviral resistance. Methods Adult recipients of allogeneic T-cell depleted SCT were studied retrospectively ( n=92). CMV infections were treated with (val)ganciclovir according to a CMV DNA-load-based pre-emptive strategy. Treatment failure was defined as a CMV DNA load of 1,000 copies/ml or more after at least 2 weeks of treatment. Resistance was analysed by nucleotide sequence analysis of the UL97 and UL54 genes in the first CMV DNA-positive sample and in samples during treatment failure. Results Treatment failure occurred in 26 of the 47 pre-emptively treated patients (55%) and in 39 of 86 (45%) treatment episodes. The risk of treatment failure was increased during first treatment episodes ( P=0.01) and during the use of immunosuppressive medication ( P=0.02). Antiviral resistance was found in only 1 patient (4%) with treatment failure. Conclusions A slow response to pre-emptive antiviral treatment occurred frequently in CMV infections in SCT recipients. Antiviral resistance was observed but played a minor role in treatment failure.

Contains fulltext : 97382.pdf (Publisher’s version ) (Open Access) BACKGROUND: One of the major challenges in allogeneic stem cell transplantation is to find a balance between the harmful induction of graft-versus-host disease and the beneficial graft-versus-leukemia and pathogen-specific immune responses. Adoptive transfer of in-vitro generated donor T cells with specific anti-leukemic or pathogen-specific activity may be effective. However, in many cases this requires the in-vitro priming and expansion of antigen-specific precursor T cells from the naive donor T-cell repertoire. DESIGN AND METHODS: Antigen-specific CD8 T cells were generated by co-culture of CD45RO-depleted, regulatory T cell-depleted donor peripheral blood mononuclear cells with autologous peptide-loaded dendritic cells, followed by two re-stimulations with peptide-loaded autologous monocytes. Responding T cells were isolated based on CD137 expression and further purified using peptide/major histocompatibility complex tetramers. RESULTS: Using this method we were able to reproducibly generate functionally high avidity T cells directed against multiple viral antigens and minor histocompatibility antigens from the naive T-cell repertoire of seronegative, minor histocompatibility antigen-negative donors. Furthermore, we demonstrated that reduction of the regulatory T-cell frequency by depletion of CD45RO(+) responder cells resulted in improved priming and expansion of antigen-specific precursor T cells. CONCLUSIONS: In conclusion, we present a robust method for the in-vitro induction and isolation of antigen-specific T cells from the naive repertoire. We demonstrate that the likelihood of successful generation of primary immune responses is determined by a delicate balance between the numbers of antigen-specific precursor T cells and the numbers and activation state of regulatory T cells locally at the site of priming of the immune response. 01 augustus 2011

The acute phase reaction is important in many disease processes. Habitual levels of the acute phase proteins fibrinogen, C-reactive protein (CRP) and interleukin-6 (IL-6) are associated with an increased risk of cardiovascular disease, but the dynamic variation of plasma levels of acute phase proteins may be of importance as well. The aim of this study was to document the variation in response by fibrinogen, CRP and IL-6 levels to a mild inflammatory stimulus (yellow fever vaccination) in 25 healthy individuals. Plasma levels of fibrinogen, CRP and IL-6 were determined at baseline and 7 days after vaccination, and genetic polymorphisms in these genes were determined. After vaccination, fibrinogen levels had changed between -13 and +44% (P = 0.003), CRP levels between -88 and +672% (not significant), and IL-6 levels between -55 and +448% (not significant). Genetic variation partly explained the interindividual variation in response, as IL-6 -174G homozygotes showed a significantly stronger increase in CRP levels than IL-6 -174C allele carriers. In conclusion, this study suggests that a large interindividual variation exists in the acute phase response to yellow fever vaccination, indicating that individuals may be classified as hyper-responders or hyporesponders, and that genetic variation may influence the responsiveness of an individual. © 2004 Lippincott Williams & Wilkins. Chemicals / CAS: C reactive protein, 9007-41-4; fibrinogen, 9001-32-5; C-Reactive Protein, 9007-41-4; Fibrinogen, 9001-32-5; Interleukin-6; Yellow Fever Vaccine

In adults with febrile urinary tract infection (fUTI), data on optimal treatment duration in patients other than non-pregnant women without comorbidities are lacking. A randomized placebo-controlled, double-blind, non-inferiority trial among 35 primary care centers and 7 emergency departments of regional hospitals in the Netherlands. Women and men aged ≥ 18 years with a diagnosis of fUTI were randomly assigned to receive antibiotic treatment for 7 or 14 days (the second week being ciprofloxacin 500 mg or placebo orally twice daily). Patients indicated to receive antimicrobial treatment for at least 14 days were excluded from randomization. The primary endpoint was the clinical cure rate through the 10- to 18-day post-treatment visit with preset subgroup analysis including sex. Secondary endpoints were bacteriologic cure rate at 10–18 days post-treatment and clinical cure at 70–84 days post-treatment. Of 357 patients included, 200 were eligible for randomization; 97 patients were randomly assigned to 7 days and 103 patients to 14 days of treatment. Overall, short-term clinical cure occurred in 85 (90%) patients treated for 7 days and in 94 (95%) of those treated for 14 days (difference –4.5%; 90% CI, –10.7 to 1.7; P non-inferiority = 0.072, non-inferiority not confirmed). In women, clinical cure was 94% and 93% in those treated for 7 and 14 days, respectively (difference 0.9; 90% CI, –6.9 to 8.7, P non-inferiority = 0.011, non-inferiority confirmed) and, in men, this was 86% versus 98% (difference –11.2; 90% CI –20.6 to –1.8, P superiority = 0.025, inferiority confirmed). The bacteriologic cure rate was 93% versus 97% (difference –4.3%; 90% CI, –9.7 to 1.2, P non-inferiority = 0.041) and the long-term clinical cure rate was 92% versus 91% (difference 1.6%; 90% CI, –5.3 to 8.4; P non-inferiority = 0.005) for 7 days versus 14 days of treatment, respectively. In the subgroups of men and women, long-term clinical cure rates met the criteria for non-inferiority, indicating there was no difference in the need for antibiotic retreatment for UTI during 70–84 days follow-up post-treatment. Women with fUTI can be treated successfully with antibiotics for 7 days. In men, 7 days of antibiotic treatment for fUTI is inferior to 14 days during short-term follow-up but it is non-inferior when looking at longer follow-up. The study was registered at ClinicalTrials.gov [ NCT00809913 ; December 16, 2008] and trialregister.nl [ NTR1583 ; December 19, 2008].