[HIV First Diagnoses in Germany in 2014 - A Regional Analysis]. / HIV-Erstdiagnosen in Deutschland im Jahr 2014 ­ eine regionale Analyse.

BACKGROUND: Information on testing units in health care is scarce, particularly the group of late-presenters among the HIV-first diagnoses is still a challenge in Germany. AIM: Analysis of the impact of testing units on and reasons for the prevalence of HIV-first diagnoses and late presentation, taking 2014 for illustrative purposes. MATERIAL AND METHODS: Cross-sectional analysis of all individuals, treated in the Network HIV-Regional who were first diagnosed with HIV in 2014; patient characteristics, demographic and clinical data, including information on HIV testing were collected retrospectively and in a decentralised manner, pseudonymized and statistically evaluated. RESULTS: A total of 971 individuals with HIV-first diagnosis from 31 specialised care centres throughout Germany (15 hospitals, 16 private practices) represented 27.5% of all National HIV-first diagnoses -registrations from Robert Koch Institute for 2014, with similar results for CD4-cell count and HIV-transmission risk. The most common test site was a hospital (34.8%), followed by the office of a family doctor (19.6%) and medical specialist (16.1%). If the first diagnosis was established in hospital, then the patients were on average older than those tested on an ambulant care basis (42 vs. 37 years, p=0.001); moreover, the HI-viral load was higher (585 vs. 270 thousand copies/mL, p<0.001) and the CD4-cell count lower (265 vs. 414/µL, p<0.001). In 208/971 individuals with first diagnosis, at least one AIDS-defining disease was found, most frequently pneumocystis-pneumonia (43.8%), candidiasis (36.5%) and Kaposi sarcoma (10.6%). A regional comparison revealed that in eastern Germany, for first diagnosed HIV-patients were younger, had a higher HIV-RNA viral load and also more often clinical AIDS. CONCLUSION: This analysis of HIV-Regional for 2014 enables a deeper insight into HIV first diagnoses, on the eve of the introduction of important prevention tools in Germany, e. g., HIV home testing and pre-exposure prophylaxis. This cross-sectional analysis was representative for Germany and underscores the importance of specialised hospitals, in particular for eastern Germany, and furthermore the involvement of late-presenters into HIV health care.

Complement activation induces excessive T cell cytotoxicity in severe COVID-19.

Severe COVID-19 is linked to both dysfunctional immune response and unrestrained immunopathology, and it remains unclear whether T cells contribute to disease pathology. Here, we combined single-cell transcriptomics and single-cell proteomics with mechanistic studies to assess pathogenic T cell functions and inducing signals. We identified highly activated CD16+ T cells with increased cytotoxic functions in severe COVID-19. CD16 expression enabled immune-complex-mediated, T cell receptor-independent degranulation and cytotoxicity not found in other diseases. CD16+ T cells from COVID-19 patients promoted microvascular endothelial cell injury and release of neutrophil and monocyte chemoattractants. CD16+ T cell clones persisted beyond acute disease maintaining their cytotoxic phenotype. Increased generation of C3a in severe COVID-19 induced activated CD16+ cytotoxic T cells. Proportions of activated CD16+ T cells and plasma levels of complement proteins upstream of C3a were associated with fatal outcome of COVID-19, supporting a pathological role of exacerbated cytotoxicity and complement activation in COVID-19.