Airway microbiome signature accurately discriminates Mycobacterium tuberculosis infection status.

Mycobacterium tuberculosis remains one of the deadliest infectious agents globally. Amidst efforts to control TB, long treatment duration, drug toxicity, and resistance underscore the need for novel therapeutic strategies. Despite advances in understanding the interplay between microbiome and disease in humans, the specific role of the microbiome in predicting disease susceptibility and discriminating infection status in tuberculosis still needs to be fully investigated. We investigated the impact of M.tb infection and M.tb-specific IFNγ immune responses on airway microbiome diversity by performing TB GeneXpert and QuantiFERON-GOLD assays during the follow-up phase of a longitudinal HIV-Lung Microbiome cohort of individuals recruited from two large independent cohorts in rural Uganda. M.tb rather than IFNγ immune response mainly drove a significant reduction in airway microbiome diversity. A microbiome signature comprising Streptococcus, Neisseria, Fusobacterium, Prevotella, Schaalia, Actinomyces, Cutibacterium, Brevibacillus, Microbacterium, and Beijerinckiacea accurately discriminated active TB from Latent TB and M.tb-uninfected individuals.

Differential expression of host protein biomarkers among symptomatic clinic attendees finally diagnosed with tuberculosis and other respiratory diseases with or without latent Mycobacterium tuberculosis infection.

BACKGROUND: There is a need for new tools for the diagnosis of tuberculosis (TB) amongst patients who present at primary health care centers with symptoms suggestive of TB. OBJECTIVES: To assess the abilities of selected blood-based host biomarkers to discriminate between patients who self-presented with symptoms suggestive of TB and were subsequently diagnosed with pulmonary tuberculosis (PTB), other respiratory diseases (ORD) with latent Mycobacterium tuberculosis infection (ORD_LTBI) or ORD without latent infection (ORD_NoLTBI). METHODS: Presumptive TB patients (n = 161) were enrolled at a TB Clinic in Kampala, Uganda, and blood was collected. Participants were later classified as having PTB or ORD using standard microbiological confirmatory tests. Patients with ORD were subsequently classified as having LTBI or no LTBI using the QuantiFERON Gold-plus test. The concentrations of 27 host biomarkers were evaluated in patient sera using the Luminex platform, followed by an evaluation of their abilities to discriminate between PTB, ORD_LTBI, and ORD_NoLTBI. RESULTS: Multiple host biomarkers including IP10, IL6, IL2, IL1ß, TNFα, IFNγ, and IL12p70, were significantly different between patients with PTB (n = 55), ORDs (n = 106), and between PTB and the two ORD sub-groups. A bio-signature comprising IP10, IL6, TNFα IL1ß, IL1ra, and IL12p70 best diagnosed PTB disease, with an area under the ROC curve of 90. CONCLUSION: We identified host biomarkers that discriminated between different M.tb infection states amongst patients who presented with symptoms requiring investigation for TB. The biomarkers that showed diagnostic potential in our study may be considered as additional candidate markers for future active PTB rapid screening tests.

Feasibility of collecting and processing of COVID-19 convalescent plasma for treatment of COVID-19 in Uganda.

INTRODUCTION: Evidence that supports the use of COVID-19 convalescent plasma (CCP) for treatment of COVID-19 is increasingly emerging. However, very few African countries have undertaken the collection and processing of CCP. The aim of this study was to assess the feasibility of collecting and processing of CCP, in preparation for a randomized clinical trial of CCP for treatment of COVID-19 in Uganda. METHODS: In a cross-sectional study, persons with documented evidence of recovery from COVID-19 in Uganda were contacted and screened for blood donation via telephone calls. Those found eligible were asked to come to the blood donation centre for further screening and consent. Whole blood collection was undertaken from which plasma was processed. Plasma was tested for transfusion transmissible infections (TTIs) and anti-SARS CoV-2 antibody titers. SARS-CoV-2 testing was also done on nasopharyngeal swabs from the donors. RESULTS: 192 participants were contacted of whom 179 (93.2%) were eligible to donate. Of the 179 eligible, 23 (12.8%) were not willing to donate and reasons given included: having no time 7(30.4%), fear of being retained at the COVID-19 treatment center 10 (43.5%), fear of stigma in the community 1 (4.3%), phobia for donating blood 1 (4.3%), religious issues 1 (4.4%), lack of interest 2 (8.7%) and transport challenges 1 (4.3%). The median age was 30 years and females accounted for 3.7% of the donors. A total of 30 (18.5%) donors tested positive for different TTIs. Antibody titer testing demonstrated titers of more than 1:320 for all the 72 samples tested. Age greater than 46 years and female gender were associated with higher titers though not statistically significant. CONCLUSION: CCP collection and processing is possible in Uganda. However, concerns about stigma and lack of time, interest or transport need to be addressed in order to maximize donations.

Efficacy of convalescent plasma for treatment of COVID-19 in Uganda.

RATIONALE: Convalescent plasma (CCP) has been studied as a potential therapy for COVID-19, but data on its efficacy in Africa are limited. OBJECTIVE: In this trial we set out to determine the efficacy of CCP for treatment of COVID-19 in Uganda. MEASUREMENTS: Patients with a positive SARS-CoV-2 reverse transcriptase (RT)-PCR test irrespective of disease severity were hospitalised and randomised to receive either COVID-19 CCP plus standard of care (SOC) or SOC alone. The primary outcome was time to viral clearance, defined as having two consecutive RT-PCR-negative tests by day 28. Secondary outcomes included time to symptom resolution, clinical status on the modified WHO Ordinal Clinical Scale (≥1-point increase), progression to severe/critical condition (defined as oxygen saturation <93% or needing oxygen), mortality and safety. MAIN RESULTS: A total of 136 patients were randomised, 69 to CCP+SOC and 67 to SOC only. The median age was 50 years (IQR: 38.5-62.0), 71.3% were male and the median duration of symptom was 7 days (IQR=4-8). Time to viral clearance was not different between the CCP+SOC and SOC arms (median of 6 days (IQR=4-11) vs 4 (IQR=4-6), p=0.196). There were no statistically significant differences in secondary outcomes in CCP+SOC versus SOC: time to symptom resolution (median=7 (IQR=5-7) vs 7 (IQR=5-10) days, p=0.450), disease progression (9 (22.0%) vs 7 (24.0%) patients, p=0.830) and mortality (10 (14.5%) vs 8 (11.9%) deaths, p=0.476). CONCLUSION: In this African trial, CCP therapy did not result in beneficial virological or clinical improvements. Further trials are needed to determine subgroups of patients who may benefit from CCP in Africa.Trial registration number NCT04542941.

Characteristics and outcomes of admitted patients infected with SARS-CoV-2 in Uganda.

RATIONALE: Detailed data on the characteristics and outcomes of patients with COVID-19 in sub-Saharan Africa are limited. OBJECTIVE: We determined the clinical characteristics and treatment outcomes of patients diagnosed with COVID-19 in Uganda. MEASUREMENTS: As of the 16 May 2020, a total of 203 cases had been confirmed. We report on the first 56 patients; 29 received hydroxychloroquine (HCQ) and 27 did not. Endpoints included admission to intensive care, mechanical ventilation or death during hospitalisation. MAIN RESULTS: The median age was 34.2 years; 67.9% were male; and 14.6% were <18 years. Up 57.1% of the patients were asymptomatic. The most common symptoms were fever (21.4%), cough (19.6%), rhinorrhea (16.1%), headache (12.5%), muscle ache (7.1%) and fatigue (7.1%). Rates of comorbidities were 10.7% (pre-existing hypertension), 10.7% (diabetes) and 7.1% (HIV), Body Mass Index (BMI) of ≥30 36.6%. 37.0% had a blood pressure (BP) of >130/90 mm Hg, and 27.8% had BP of >140/90 mm Hg. Laboratory derangements were leucopenia (10.6%), lymphopenia (11.1%) and thrombocytopenia (26.3%). Abnormal chest X-ray was observed in 14.3%. No patients reached the primary endpoint. Time to clinical recovery was shorter among patients who received HCQ, but this difference did not reach statistical significance. CONCLUSION: Most of the patients with COVID-19 presented with mild disease and exhibited a clinical trajectory not similar to other countries. Outcomes did not differ by HCQ treatment status in line with other concluded studies on the benefit of using HCQ in the treatment of COVID-19.