Efficacy and safety of in-hospital treatment of Covid-19 infection with low-dose hydroxychloroquine and azithromycin in hospitalized patients: A retrospective controlled cohort study.

Objectives: In this study we evaluate the efficacy and safety of a treatment protocol with standard dose of hydroxychloroquine plus azithromycin in patients hospitalized with COVID-19 infection. Methods: We conducted a retrospective analysis to compare the 28-day mortality rate in 352 patients treated with hydroxychloroquine with or without azithromycin (HCQ-group) in our hospital with a contemporary control group of 3533 patients receiving standard of care from the Belgian Collaborative Group on COVID-19 Hospital Surveillance. Results: All patients who received at least one dose of treatment were included in the analysis. A statistically significant reduction in crude mortality rate at 28 days was observed in the HCQ-group compared to standard of care (16.8% vs 25.9%,p â€‹= â€‹0.001).Patients in the treatment group were on average younger (69,7 vs73,1 years, p â€‹= â€‹0,0002), were less likely to smoke or to have malignancy and more likely to be male. Patients in the treatment group were more likely to be obese, immunocompromised or to have arterial hypertension, liver disease and lung disease.After adjustment for these variables the OR for mortality was 0.635 (95%CI 0.464-0.875). Patients who did not receive HCQ had a 57% higher risk of mortality. A survival benefit in the treatment group was consistent across all age groups. 13 patients discontinued treatment due to side effects (4 with QTc-prolongation>60msec (1.1%) and 9 because of gastro-intestinal symptoms (2.55%)). No episodes of ventricular arrhythmia or torsade de pointes were recorded during treatment. Conclusion: Treatment of COVID-19 using a combination of hydroxychloroquine plus azithromycin was safe and was associated with a statistically significant mortality benefit in the treatment of COVID-19 infection in hospitalized patients. Our findings do not support the current negative recommendations regarding this treatment.

VIDAS3® TB-IGRA assay: evaluation of performance characteristics in a predominantly low risk, low incidence population.

OBJECTIVES: To evaluate the analytical performance of the TB-IGRA® assay on the VIDAS3 platform (bioMérieux) when testing a predominantly low risk population in a low incidence area. RESULTS: Eighty-eight percent of the results were concordant between QuantiFERON®-TB Gold-Plus (QFT®-Plus, QIAGEN) and TB-IGRA®. All 12 of 99 (12.1%) discordant results were determined positive only with the TB-IGRA® assay. In 11 of 12 of these discordant cases, no explanation could be found in the medical record. Five of these discrepant results were probably caused by the use of contaminated stimulation reagents. The remaining 6 discrepant samples were also part of the reproducibility experiment and only 2 results were reproducible positive. Overall, in the reproducibility experiment 5 of 25 (20.0 %) results were not repeatable. CONCLUSIONS: the TB-IGRA® assay seems prone to contamination. Besides, we documented a reproducibility of only 80.0% with the TB-IGRA® assay.

Ruminococcus gnavus bacteremia, an uncommon presentation of a common member of the human gut microbiota: case report and literature review.

Case report: We present a case of a 66-year-old female diagnosed with R. gnavus bacteremia associated with fecal peritonits secondary to small-bowel herniation and perforation. Identification  as R. gnavus was delayed because of absence of this species in the MALDI-TOF MS database (Vitek MS, bioMérieux). Identification was provided by 16S rRNA gene sequencing. Review: R. gnavus, a Gram-positive, strictly anaerobic bacterium, is a member of the human gut microbiota. Dysbiosis in the gut microbiota, with increased amounts of R. gnavus, has been described in inflammatory bowel disease. R. gnavus has only been reported occasionally as the cause of infections. Hence the potential pathogenicity is not yet fully recognized, and data regarding the antimicrobial susceptibility profile are rare. Identification of anaerobic bacteria such as R. gnavus is greatly accelerated  as a result of the introduction of MALDI-TOF MS. However, as illustrated in this case report, an extensive and up-to-date MALDI-TOF MS database is necessary for providing an accurate identification.

Distribution of HCV genotypes in Belgium from 2008 to 2015.

BACKGROUND: The knowledge of circulating HCV genotypes and subtypes in a country is crucial to guide antiviral therapy and to understand local epidemiology. Studies investigating circulating HCV genotypes and their trends have been conducted in Belgium. However they are outdated, lack nationwide representativeness or were not conducted in the general population. METHODS: In order to determine the distribution of different circulating HCV genotypes in Belgium, we conducted a multicentre study with all the 19 Belgian laboratories performing reimbursed HCV genotyping assays. Available genotype and subtype data were collected for the period from 2008 till 2015. Furthermore, a limited number of other variables were collected: some demographic characteristics from the patients and the laboratory technique used for the determination of the HCV genotype. RESULTS: For the study period, 11,033 unique records collected by the participating laboratories were used for further investigation. HCV genotype 1 was the most prevalent (53.6%) genotype in Belgium, with G1a and G1b representing 19.7% and 31.6%, respectively. Genotype 3 was the next most prevalent (22.0%). Further, genotype 4, 2, and 5 were responsible for respectively 16.1%, 6.2%, and 1.9% of HCV infections. Genotype 6 and 7 comprise the remaining <1%. Throughout the years, a stable distribution was observed for most genotypes. Only for genotype 5, a decrease as a function of the year of analysis was observed, with respectively 3.6% for 2008, 2.3% for 2009 and 1.6% for the remaining years. The overall M:F ratio was 1.59 and was mainly driven by the high M:F ratio of 3.03 for patients infected with genotype 3. Patients infected with genotype 3 are also younger (mean age 41.7 years) than patients infected with other genotypes (mean age above 50 years for all genotypes). The patients for whom a genotyping assay was performed in 2008 were younger than those from 2015. Geographical distribution demonstrates that an important number of genotyped HCV patients live outside the Belgian metropolitan cities. CONCLUSION: This national monitoring study allowed a clear and objective view of the circulating HCV genotypes in Belgium and will help health authorities in the establishment of cost effectiveness determinations before implementation of new treatment strategies. This baseline characterization of the circulating genotypes is indispensable for a continuous surveillance, especially for the investigation of the possible impact of migration from endemic regions and prior to the increasing use of highly potent direct-acting antiviral (DAA) agents.

Corynebacterium lowii sp. nov. and Corynebacterium oculi sp. nov., derived from human clinical disease and an emended description of Corynebacterium mastitidis.

Strains of members of the genus Corynebacterium derived from ophthalmologic patients in Japan, Belgium and Switzerland and found to be closely related to-, but distinguishable from Corynebacterium mastitidis by 16S rRNA gene sequencing, were characterized using biochemical, chemotaxonomic, MALDI-TOF mass spectrometry and antimicrobial susceptibility methods and DNA-DNA hybridization as well as by whole-genome sequencing (WGS). Based on this investigation, we describe Corynebacterium lowii sp. nov. and Corynebacterium oculi sp. nov., derived from human ocular specimens, as well as emend the description of Corynebacterium mastitidis. Type strains for these species are: C. lowii R-50085T (=LMG 28276T =CCUG 65815T) and C. oculi R-50187T (=LMG 28277T =CCUG 65816T). DNA G+C content was found to be 62.2 % (by HPLC) and 62.8 % (by WGS) for C. lowii R-50085T, 64.1 % (HPLC) and 64.8 % (WGS) for C. oculi R-50187T and 67.8 % (HPLC) for C. mastitidis LMG 19040T [=S-8T =CCUG 38654T =CECT 4843T =CIP 105509T =DSM 44356T =IFO (NBRC)16160T =JCM 12269T].

Monitoring the patient response as an alternative to commercial negative quality control in infectious serology.

BACKGROUND: Traditional internal quality control schemes for qualitative infectious serology mostly rely on the use of commercial positive and negative quality control materials. However, with respect to the negative control, target values provided by the manufacturer are often poorly defined and non-commutability of the commercial materials further complicates correct interpretation of control results. An alternative quality control procedure using the median patient seronegative response is presented. STUDY DESIGN: Daily patient median responses were calculated for our Hepatitis B surface antigen, Hepatitis B core antibody, Hepatitis C antibody and HIV antigen/antibody test systems. Because of the low prevalence of these viruses in our area, most patient responses are negative. A minimum of 5 patient samples per day was required to generate a stable daily median. Control limits were calculated and daily patient medians were plotted against commercial quality control results. RESULTS: Commercial negative controls and daily patient medians mostly behaved in the same way. Nevertheless, for the Hepatitis B surface antigen test, patient medians frequently exceeded the calculated control limit in contrast to commercial quality controls. This confirms that target ranges provided by the manufacturer are not always adequate. Moreover, an important matrix-related interference occurred on our HIV antigen/antibody test system and correct interpretation was only possible using daily patient median results. CONCLUSION: Monitoring the daily patient median response can be a valuable alternative to traditional commercial negative quality control. It's easy to perform, cost-free, provides additional information with respect to matrix effects and allows for the establishment of well-defined control limits.

Actinomyces urogenitalis bacteremia and tubo-ovarian abscess after an in vitro fertilization (IVF) procedure.

We describe the first case of bacteremia due to Actinomyces urogenitalis. Bacteremia was secondary to a tubo-ovarian abscess following transvaginal oocyte retrieval. Identification was established by matrix-assisted desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and confirmed by 16S rRNA gene sequencing. A. urogenitalis should be considered as a potential causative agent of infection after gynecological procedures.

The human androgen receptor X-chromosome inactivation assay for clonality diagnostics of natural killer cell proliferations.

Clonality is a frequently exploited characteristic of lymphoid malignancies. However, in the natural killer (NK) cell subset of large granular lymphocyte proliferations, clonality is difficult to prove because of the lack of specific genetic markers, such as immunoglobulin or T-cell receptor gene rearrangements. The human androgen receptor (HUMARA) assay, a polymerase chain reaction-based X-chromosome inactivation assay, is a potential diagnostic tool in these disorders. Although there is much experience with X-chromosome inactivation assays in myeloid proliferations, these assays have found only very limited application in clonality assessment of NK cell proliferations. We applied the HUMARA assay in laboratory diagnostics for detection of clonality in NK cell proliferations. We describe its test performance and report three cases in which clonality of NK cell populations was investigated by use of this assay. Our results demonstrate the usefulness of the HUMARA assay in the diagnostic workup of NK cell proliferations.

Molecular diagnosis of invasive aspergillosis: the long and winding road.

Invasive aspergillosis is a major cause of morbidity and mortality in patients with hematological malignancies and stem cell transplant recipients. Early diagnosis and therapy are important to improve prognosis in these patients. Difficulties in establishing an early diagnosis have prompted investigations towards new and alternative diagnostic methods. During the last decade, PCR-based assays have emerged as valuable experimental tools to improve diagnostic workup and clinical management of patients with suspected or proven invasive aspergillosis. However, implementation of these molecular tools in the routine diagnostic laboratory is hampered by a lack of standardization.

Blockade of CTLA-4 (CD152) enhances the murine antibody response to pneumococcal capsular polysaccharides.

The capsular polysaccharides (caps-PS) of Streptococcus pneumoniae are classified as thymus-independent antigens. Nevertheless, T lymphocytes can modulate the antibody response to caps-PS. In this study, we show that anticytotoxic T lymphocyte-associated antigen 4 (CTLA-4) treatment, along with administration of caps-PS to BALB/c mice, resulted in a dose-dependent generation of a strong caps-PS-specific antibody response. Anti-CTLA-4 treatment had no effect on the immunoglobulin G (IgG) antibody production in athymic nu/nu mice. Anti-CTLA-4 treatment stimulated the IgG antibody production in severe combined immunodeficiency (SCID)/SCID mice reconstituted with CTLA-4(-/-) B lymphocytes and wild-type T lymphocytes. This excluded the possibility that anti-CTLA-4 enhanced antibody production by direct interaction with B lymphocytes. Anti-CTLA-4 treatment enhanced the antibody production in SCID/SCID mice reconstituted with B lymphocytes and CD4(+) and CD8(+) T lymphocytes but not in SCID/SCID mice reconstituted with B lymphocytes in the absence of CD4(+) and/or CD8(+) cells. Administration of anti-CTLA-4 in BALB/c mice but not in nu/nu mice resulted in a markedly increased production of interleukin (IL)-2, IL-4, and interferon-gamma. Taken together, these data strongly suggest a role of T lymphocytes and CTLA-4 in the regulation of the antibody response to caps-PS.