Metagenomic next-generation sequencing as a diagnostic tool in the clinical routine of an infectious diseases department: a retrospective cohort study.

BACKGROUND: Metagenomic next-generation sequencing (mNGS) of circulating cell-free DNA from plasma is a hypothesis-independent broadband diagnostic method for identification of potential pathogens. So far, it has only been investigated in special risk populations (e.g. patients with neutropenic fever). PURPOSE: To investigate the extent to which mNGS (DISQVER® platform) can be used in routine clinical practice. METHODS: We collected whole blood specimens for mNGS testing, blood cultures (BC), and pathogen-specific PCR diagnostics. Clinical data and pathogen diagnostics were retrospectively reviewed by an infectious disease expert panel regarding the adjustment of anti-infective therapy. RESULTS: In 55 selected patients (median age 53 years, 67% male) with heterogeneous diagnoses, a total of 66 different microorganisms and viruses were detected using mNGS (51% viruses, 38% bacteria, 8% fungi, 3% parasites). The overall positivity rate of mNGS was 53% (29/55). Fifty-two out of 66 (79%) potential pathogens detected by mNGS were found in patients with primary or secondary immunodeficiency. The concordance rates of BC and pathogen-specific PCR diagnostics with mNGS testing were 14% (4/28) and 36% (10/28), respectively (p < 0.001). An additional bacterial pathogen (Streptococcus agalactiae) could only be detected by BC. Therapeutic consequences regarding anti-infective therapy were drawn from 23 pathogens (35% of detections), with 18 of these detections occurring in patients with immunodeficiency. CONCLUSIONS: We conclude that mNGS is a useful diagnostic tool, but should only be performed selectively in addition to routine diagnostics of infectious diseases. The limited number of patients and the retrospective study design do not allow any further conclusions.

COVID-19 treatment strategies with drugs centrally procured by the German Federal Ministry of Health in a representative tertiary care hospital: a temporal analysis.

Introduction: To ensure the fastest and earliest possible treatment, the German Federal Ministry of Health (BMG) initiated central procurement and nationwide distribution of new drugs against COVID-19. A single centre was used for a retrospective temporal analysis of this procedure. Methods: A descriptive analysis of hospitalization and treatment of COVID-19 patients with drugs centrally procured by the BMG at St. Georg Hospital, Leipzig, Germany, for the period from 1 March 2020 to 28 February 2023 was employed considering the approval status, evolving guidelines and recommendations of medical societies. Results: In total, 3,412 patients ≥18 years (54.9% men) with PCR-confirmed SARS-CoV-2 infection were admitted. The mean age was 64 years during the reporting period and 66.1/70.6 years during the first and second COVID-19 waves, respectively. 964 patients (28.2%) received COVID-19 therapy with drugs procured centrally by the BMG. Remdesivir was the most commonly used (63%). SARS-CoV-2 neutralizing monoclonal antibodies represented 23% of the therapies. Peroral antivirals (nirmatrelvir/ritonavir and molnupiravir) were used in 14% of COVID-19 patients, with molnupiravir being insignificant (five prescriptions). Conclusions: Specific therapeutic approaches were mainly based on antiviral therapy in the early phase of COVID-19 to prevent severe disease progression in vulnerable patient groups. Most drugs had not been approved at the time of central procurement; therefore, prescriptions were given on a case-by-case basis after careful risk-benefit assessments. All available neutralizing monoclonal SARS-CoV-2 antibodies lost efficacy during the pandemic due to different circulating immune escape variants. Remdesivir and nirmatrelvir/ritonavir remained effective therapies in the early phase of COVID-19.

Clinical outcomes of hospitalized COVID-19 patients treated with remdesivir: a retrospective analysis of a large tertiary care center in Germany.

PURPOSE: The benefits of antiviral treatment with remdesivir in hospitalized patients with COVID-19 remain controversial. Clinical analyses are needed to demonstrate which patient populations are most likely to benefit. METHODS: In a retrospective monocentric analysis, patients with COVID-19 treated between July 1, 2020 and June 30, 2021 at Hospital St. Georg, Leipzig, Germany were evaluated. The primary endpoint was time to clinical improvement, and the secondary endpoint was 28-day mortality. Propensity score matching was used for the endpoint analysis. RESULTS: A total of 839 patients were fully evaluated, 68% of whom received specific COVID-19 drug therapy. Remdesivir was used in 31.3% of the patients, corticosteroids in 61.7%, and monoclonal antibodies in 2.3%. While dexamethasone administration was the most common therapeutic approach during the second pandemic wave, combination therapy with remdesivir and corticosteroids predominated during the third wave. Cox regression analysis revealed that combination therapy was not associated with faster clinical improvement (median: 13 days in both matched groups, HR 0.97 [95% CI 0.77-1.21], P = 0.762). By contrast, 28-day mortality was significantly lower in the corticosteroid-remdesivir group (14.8% versus 22.2% in the corticosteroid group, HR 0.60 [95% CI 0.39-0.95], P = 0.03) in the low-care setting. This effect was also demonstrated in a subgroup analysis of patients with remdesivir monotherapy (n = 44) versus standard of care (SOC). CONCLUSION: In COVID-19 patients with only mild disease (low-flow oxygen therapy and treatment in a normal ward) who received corticosteroids and/or remdesivir in addition to SOC, early administration of remdesivir was associated with a measurable survival benefit.

Low colonization rates with Multidrug-resistant Gram-negative bacteria in a German hospital-affiliated hemodialysis center.

BACKGROUND: Multidrug-resistant Gram-negative bacteria (MDRGN) are found with rising prevalence in non-hemodialysis risk populations as well as hemodialysis (HD) cohorts in Asia, Europe and North America. At the same time, colonization and consecutive infections with such pathogens may increase mortality and morbidity of affected individuals. We aimed to monitor intestinal MDRGN colonization in a yet not investigated German HD population. METHODS: We performed cross-sectional point-prevalence testing with 12 months follow-up and selected testing of relatives in an out-patient HD cohort of n = 77 patients by using microbiological cultures from fresh stool samples, combined with Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF-MS) and antimicrobial susceptibility testing. RESULTS: We detected MDRGN in 8 out of 77 patients (10.4%) and 1 out of 22 relatives (4.5%), indicating only colonization and no infections. At follow-up, 2 patients showed phenotypic persistence of MDRGN colonization, and in 6 other patients de-novo MDRGN colonization could be demonstrated. Pathogens included Escherichia coli and Klebsiella pneumoniae (with extended-spectrum beta-lactamase [ESBL]-production as well as fluoroquinolone resistance), Stenotrophomonas maltophilia and Enterobacter cloacae. CONCLUSIONS: In a single-center study, MDRGN colonization rates were below those found in non-HD high-risk populations and HD units in the US, respectively. Reasons for this could be high hygiene standards and a strict antibiotic stewardship policy with evidence of low consumption of fluoroquinolones and carbapenems in our HD unit and the affiliated hospital.

Cell death induced by 131 I in a differentiated thyroid carcinoma cell line in vitro: necrosis or apoptosis?

AIM: The apoptotic and necrotic dose-response of thyroid carcinoma cells following irradiation with I was evaluated. METHODS: In our in-vitro model, cells of well-differentiated papillary thyroid carcinoma (B-CPAP) were incubated with increasing activity concentrations of I for 2 days. Changes in cell viability and the extents of necrosis and apoptosis were evaluated both immediately and 2 days after irradiation. RESULTS: Viability of B-CPAP cells diminished with increasing I activity concentration. No apoptosis was detectable immediately after irradiation. Two days after irradiation significant apoptosis was found. The lowest I activity concentration at which apoptosis was detectable corresponds to about 1 MBq . ml. At higher activity concentrations a larger percentage of cells became apoptotic but the proportion decreased again at activity concentrations >10 MBq . ml. Likewise, necrosis was minimal at low activity concentrations and showed an exponential increase with rising I activity concentrations (>5-10 MBq . ml). Necrosis was already detectable immediately after irradiation and was the predominant form of cell death at high activity concentrations. CONCLUSION: The data suggest that the nature of the cytotoxic effect of I and whether it leads to apoptotic or necrotic cell death is dose-dependent. High I doses seem to produce mainly necrotic phenomena, whereas at low I activity concentrations apoptotic phenomena prevail. The predominance of delayed apoptosis could explain why radioiodine therapy at lower doses is often linked to delayed onset and possible continuation of thyroid volume reduction over some months and even up to a year.