Laboratory Dr. Wisplinghoff

Introduction: Mold, which includes the components and metabolic products of mold fungi as well as other factors associated with moisture, such as yeasts, bacteria (actinobacteria) and mites, occurs indoors when there is increased moisture. In addition to known causes of damp/mold damage such as structural defects (including thermal bridges, rising damp, insufficient ventilation), water damage and incorrect ventilation and heating options, construction work plays an important role in hospitals and medical practices.Methods: The AWMF S2k guideline “Medical clinical diagnostics for indoor mold exposure” was first published in 2016. Following a new systematic literature search, an updated version of this guideline was published in October 2023 with the cooperation of various medical disciplines and other experts. The guideline is intended to close the existing knowledge gap in terms of rational and efficient medical diagnosis in cases of indoor mold contamination. Recommendations are given on general and specific examination methods. Non-evidence-based diagnostic methods, some of which are still used in practice, are not recommended. Furthermore, treatment options for health problems and diseases caused by mold fungi are presented. It is explained why, in most cases, indoor measurements of molds, their components or metabolites are not required for medical evaluation. Results: Individuals who are immunosuppressed (grade 2 and 3 of the immunosuppression grades according the Commission for Hospital Hygiene and Infection Prevention [KRINKO] at the Robert Koch Institute [RKI]), or are suffering from severe influenza, severe COVID-19, cystic fibrosis and uncontrolled bronchial asthma are at increased risk of exposure to mold fungi. For these patients, exposure to mold damage must be ruled out in the clinic and practice as well as in the home environment.Conclusion: If, despite all precautionary measures, moisture/mold damage can be detected in the environment of these particularly vulnerable patients, it must be remediated immediately. Indoor measurements of mold exposure are not indicated for medical reasons. Rather, all measures that help to avoid moisture damage are crucial for prevention.

Dengue is an increasing threat to individuals living in or visiting endemic countries. Effective vaccines have become available, but their use in travelers is typically only recommended to individuals with documented prior infection. We present a fatal case of severe dengue in an unvaccinated traveler without known prior dengue virus infection but longitudinal serologic and molecular evidence for secondary infection. In the context of this case and vaccination guidance for travelers, we discuss pre-vaccination screening, potential implications for travelers to regions with ongoing outbreaks, and emphasize the importance of serostatus-independent vaccines.

BACKGROUNDThe fungus Aspergillus fumigatus causes a variety of clinical phenotypes in patients with cystic fibrosis (pwCF). Th cells orchestrate immune responses against fungi, but the types of A. fumigatus-specific Th cells in pwCF and their contribution to protective immunity or inflammation remain poorly characterized.METHODSWe used antigen-reactive T cell enrichment (ARTE) to investigate fungus-reactive Th cells in peripheral blood of pwCF and healthy controls.RESULTSWe show that clonally expanded, high-avidity A. fumigatus-specific effector Th cells, which were absent in healthy donors, developed in pwCF. Individual patients were characterized by distinct Th1-, Th2-, or Th17-dominated responses that remained stable over several years. These different Th subsets target different A. fumigatus proteins, indicating that differential antigen uptake and presentation directs Th cell subset development. Patients with allergic bronchopulmonary aspergillosis (ABPA) are characterized by high frequencies of Th2 cells that cross-recognize various filamentous fungi.CONCLUSIONOur data highlight the development of heterogenous Th responses targeting different protein fractions of a single fungal pathogen and identify the development of multispecies cross-reactive Th2 cells as a potential risk factor for ABPA.FUNDINGGerman Research Foundation (DFG), under Germany's Excellence Strategy (EXC 2167-390884018 "Precision Medicine in Chronic Inflammation" and EXC 2051-390713860 "Balance of the Microverse"); Oskar Helene Heim Stiftung; Christiane Herzog Stiftung; Mukoviszidose Institut gGmb; German Cystic Fibrosis Association Mukoviszidose e.V; German Federal Ministry of Education and Science (BMBF) InfectControl 2020 Projects AnDiPath (BMBF 03ZZ0838A+B).

The understanding of longitudinal changes in the urinary microbiota of healthy women and its relation to intestinal microbiota is limited. From a cohort of 15 premenopausal women without known urogenital disease or current symptoms, we collected catheter urine (CU), vaginal and periurethral swabs, and fecal samples on four visits over six months. Additionally, ten participants provided CU and midstream urine (MU) to assess comparability. Urine was subjected to expanded culture. 16S rRNA gene sequencing was performed on all urine, fecal, and selected vaginal and periurethral samples. Sequence reads were processed (DADA2 pipeline) and analyzed using QIIME 2 and R. Relative abundances of urinary microbiota were variable over 6-18 months. The degree of intraindividual variability of urinary microbiota was higher than that found in fecal samples. Still, nearly half of the observed beta diversity of all urine samples could be attributed to differences between volunteers (R2 = 0.48, p = 0.001). After stratification by volunteer, time since last sexual intercourse was shown to be a factor significantly contributing to beta diversity (R2 = 0.14, p = 0.001). We observed a close relatedness of urogenital microbial habitats and a clear distinction from intestinal microbiota in the overall betadiversity analysis. Microbiota compositions derived from MU differed only slightly from CU compositions. Within this analysis of low-biomass samples, we identified contaminating sequences potentially stemming from sequencing reagents. Results from our longitudinal cohort study confirmed the presence of a rather variable individual urinary microbiota in premenopausal women. These findings from catheter urine complement previous observations on temporal dynamics in voided urine. The higher intraindividual variability of urinary microbiota as compared to fecal microbiota will be a challenge for future studies investigating associations with urogenital diseases and aiming at identifying pathogenic microbiota signatures.

Abstract IntroductionProphylactic vaccination against SARS-CoV-2 is one of the most important measures to contain the COVID-19 pandemic. Recently, break-through infections following vaccination against this virus have been reported. Here, we describe the humoral immune response of break-through infections in fully vaccinated individuals of old age from an outbreak in a nursery home.MethodsIn cooperation with the local health authority, blood samples from fully vaccinated and infected as well as fully vaccinated and uninfected residents of the nursery home were collected four weeks after the onset of the outbreak. The humoral immune response was determined in a neutralisation assay with replication-competent virus isolates and by a quantitative ELISA.ResultsIn this outbreak a total of 23 residents and four health care workers were tested positive for SARS-CoV-2. Four residents were unvaccinated, including one with a severe course of disease who later deceased. Despite their old age, all vaccinated residents showed no or only mild disease. Comparison of the humoral immune response revealed significantly higher antibody levels in fully vaccinated infected individuals compared to fully vaccinated uninfected individuals (p<0.001). Notably, although only a minority of the vaccinated uninfected group showed neutralisation capacity against SARS-CoV-2, all vaccinated and infected individuals showed high-titer neutralisation of SARS-CoV-2 including the alpha and beta variant.DiscussionLarge SARS-CoV-2 outbreaks can occur in fully vaccinated populations, but seem to associate with mild disease. SARS-CoV-2 infection in fully vaccinated individuals is a strong booster of the humoral immune response providing enhanced neutralisation capacity against immune evasion variants.

Liver fibrosis is the major determinant of liver related complications in patients with non-alcoholic fatty liver disease (NAFLD). A gut microbiota signature has been explored to predict advanced fibrosis in NAFLD patients. The aim of this study was to validate and compare the diagnostic performance of gut microbiota-based approaches to simple non-invasive tools for the prediction of advanced fibrosis in NAFLD. 16S rRNA gene sequencing was performed in a cohort of 83 biopsy-proven NAFLD patients and 13 patients with non-invasively diagnosed NAFLD-cirrhosis. Random Forest models based on clinical data and sequencing results were compared with transient elastography, the NAFLD fibrosis score (NFS) and FIB-4 index. A Random Forest model containing clinical features and bacterial taxa achieved an area under the curve (AUC) of 0.87 which was only marginally superior to a model without microbiota features (AUC 0.85). The model that aimed to validate a published algorithm achieved an AUC of 0.71. AUC’s for NFS and FIB-4 index were 0.86 and 0.85. Transient elastography performed best with an AUC of 0.93. Gut microbiota signatures might help to predict advanced fibrosis in NAFLD. However, transient elastography achieved the best diagnostic performance for the detection of NAFLD patients at risk for disease progression.