Assessment of lung injury severity using ultrasound in critically ill COVID-19 patients in resource limited settings.

BACKGROUND: Lung ultrasound is a non-invasive tool available at the bedside for the assessment of critically ill patients. The objective of this study was to evaluate the usefulness of lung ultrasound in assessing the severity of SARS-CoV-2 infection in critically-ill patients in a low-income setting. METHODS: We conducted a 12-month observational study in a university hospital intensive care unit (ICU) in Mali, on patients admitted for COVID-19 as diagnosed by a positive polymerase chain reaction for SARS-CoV-2 and/or typical lung computed tomography scan findings. RESULTS: The inclusion criteria was met by 156 patients with a median age of 59 years. Almost all patients (96%) had respiratory failure at admission and many needed respiratory support (121/156, 78%). The feasibility of lung ultrasound was very good, with 1802/1872 (96%) quadrants assessed. The reproducibility was good with an intra-class correlation coefficient of elementary patterns of 0.74 (95% CI 0.65, 0.82) and a coefficient of repeatability of lung ultrasound score < 3 for an overall score of 24. Confluent B lines were the most common lesions found in patients (155/156). The overall mean ultrasound score was 23 ± 5.4, and was significantly correlated with oxygen saturation (Pearson correlation coefficient of - 0.38, p < 0.001). More than half of the patients died (86/156, 55.1%). The factors associated with mortality, as shown by multivariable analysis, were: the patients' age; number of organ failures; therapeutic anticoagulation, and lung ultrasound score. CONCLUSION: Lung ultrasound was feasible and contributed to characterize lung injury in critically-ill COVID-19 patients in a low income setting. Lung ultrasound score was associated with oxygenation impairment and mortality.

Identifying Risk Factors for Pulmonary Tuberculosis Diagnosis Delays in Mali a West-African Endemic Country.

Background: Tuberculosis was the deadliest infectious agent before covid-19; 1.5 million deaths in 2020. Despite, a variety, of easy and cheap diagnostic tools, detection rates still fall below 90%; diagnosis delays are long exceeding 30 days in many continents. This study aimed to determine risk factors for pulmonary TB diagnosis delays in Mali. Methods: A cross-sectional study was conducted in Bamako to include pulmonary TB patients at treatment initiation centers. Verbal consent was obtained before the interview. Demographics, clinical, treatment cost, and patient, medical, and diagnostic delays were computed using SPSS 25.0 considering a significance level p < 0.05. Results: In total 266 patients were included, 80.8% were male, mean age was ± 12 years, primary education level was 50.4%, treatment cost before diagnosis was 100 - 200 thousand CFA in 65.4%, smokers were 42.1%, median patient, medical and total diagnostic delays were 58, 57 and 114 days respectively. Education level below university, social reasons, and non-request of health workers were identified as independent risk factors for diagnostic delay > 100 days in Mali. Conclusion: Diagnostic delay is relatively very long in Mali, there is an urgent need for identification and action to shorten the delays to limit the transmission chain and avoid disabling pulmonary sequels.

Point-of-care ultrasound for tuberculosis management in Sub-Saharan Africa-a balanced SWOT analysis.

Point-of-care ultrasound (POCUS) is an increasingly accessible skill, allowing for the decentralization of its use to nonspecialist healthcare workers to guide routine clinical decision-making. The advent of ultrasound-on-a-chip has transformed the technology into a portable mobile health device. Because of its high sensitivity to detect small consolidations, pleural effusions, and subpleural nodules, POCUS has recently been proposed as a sputum-free likely triage tool for tuberculosis (TB). To make an objective assessment of the potential and limitations of POCUS in routine TB management, we present a Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis based on a review of the relevant literature and focusing on Sub-Saharan Africa (SSA). We identified numerous strengths and opportunities of POCUS for TB management, e.g., accessible, affordable, easy to use and maintain, expedited diagnosis, extrapulmonary TB detection, safer pleural/pericardial puncture, use in children/pregnant women/people living with HIV, targeted screening of TB contacts, monitoring TB sequelae, and creating artificial intelligence decision support. Weaknesses and external threats such as operator dependency, lack of visualization of central lung pathology, poor specificity, lack of impact assessments and data from SSA must be taken into consideration to ensure that the potential of the technology can be fully realized in research as in practice.

Development and clinical evaluation of a new multiplex PCR assay for a simultaneous diagnosis of tuberculous and nontuberculous mycobacteria.

BACKGROUND: The prevalence of non-tuberculous mycobacteria (NTM) has been increasing worldwide in both developed and developing countries. NTM infection is clinically indistinguishable from tuberculosis and therefore poses significant challenges in patient management, especially in patients chronically treated for pulmonary TB. In this study, we evaluated a new highly sensitive Multiplex MTB/NTM assay that can differentiate M. tuberculosis complex (MTBC) from all NTM, including the treatable and most common NTM, M. avium complex (MAC). METHODS: We developed and optimized a new open- Multiplex MTB/NTM assay with two gene-targets for MTBC (IS6110/senX3-regX3) and two targets for MAC (IS1311/DT1) with samples spiked with stored strains and testing 20 replicates. Patients with presumptive TB and NTM were enrolled at the Respiratory Disease Department of The University Teaching Hospital of Point G, in Mali. FINDINGS: In the development stage, the new assay showed a high analytic performance with 100% detections of MTBC and MAC at only 5 colony forming units (CFUs). Overall, without the treatment failure cases, the Multiplex assay and the Xpert showed a sensitivity, specificity, PPV and NPV of 83·3% [66·4-92·6], 96·6% [88·6-99·0], 92·5% [82·3-96·5] and 92·2% [82·7-96·5] and the Xpert had values of 96·7% [83·3-99·4], 80·0% [68·2-88·1], 70·7 [55·5-82·3] and 97·9% [89·3-99·6], respectively. The Multiplex assay successfully detected all (5/5) the MAC cases. INTERPRETATION: Our new Multiplex assay demonstrates better specificity than Xpert for all group studied, in addition to detecting potential NTM cases. The assay could therefore complement the widely used Xpert assay and enhance discrimination of TB and NTM infections. FUNDING: This work was supported by the National Institutes of Health (R03AI137674, U54EB027049, D43TW010350 and UM1AI069471) and Northwestern University's Institute for Global Health Catalyzer Fund.

Clinical risk factors associated with multidrug-resistant tuberculosis (MDR-TB) in Mali.

BACKGROUND: MDR-TB is a major threat to global TB control. In 2015, 580,000 were treated for MDR-TB worldwide. The worldwide roll-out of GeneXpert MTB/RIF® has improved diagnosis of MDR-TB; however, in many countries laboratories are unable to assess drug resistance and clinical predictors of MDR-TB could help target suspected patients. In this study, we aimed to determine the clinical factors associated with MDR-TB in Bamako, Mali. METHODS: We performed a cross-sectional study of 214 patients with presumed MDR-TB admitted to University of Bamako Teaching Hospital, Point-G between 2007 and 2016. We calculated crude and adjusted odds ratios for MDR-TB disease diagnosis using SPSS. RESULTS: We found that age ≤40years (OR=2.56. 95% CI: 1.44-4.55), two courses of prior TB treatment (OR=3.25, 95% CI: 1.44-7.30), TB treatment failure (OR=3.82, 95% CI 1.82-7.79), sputum microscopy with 3+ bacilli load (OR=1.98, 95% CI: 1.13-3.48) and a history of contact with a TB patient (OR=2.48, 95% CI: 1.11-5.50) were significantly associated with confirmation of MDR-TB disease. HIV was not a risk factor for MDR-TB (aOR=0.88, 95% CI: 0.34-1.94). CONCLUSION: We identified several risk factors that could be used to identify MDR-TB suspects and prioritize them for laboratory confirmation. Prospective studies are needed to understand factors associated with TB incidence and clinical outcomes of TB treatment and disease.