Utility of Xpert MTB/RIF using bronchoalveolar lavage samples for the diagnosis of pulmonary tuberculosis in negative or sputum-scarce adults: a systematic review and meta-analysis protocol.

Abstract

Tuberculosis is the leading cause of death globally from a single infectious agent. Early diagnosis is critical to reducing morbimortality. In cases of negative smear microscopy or limited sputum production, bronchoalveolar lavage (BAL) samples offer an alternative for diagnosis. Culture, the gold standard, requires a high bacterial load, extensive infrastructure and is time-consuming. Xpert MTB/RIF provides faster results with a higher cost. Previous systematic reviews present substantial limitations, including significant heterogeneity. Therefore, the diagnostic utility of Xpert MTB/RIF using BAL samples in adults with negative or scant sputum for pulmonary tuberculosis (PTB) needs to be reassessed. A systematic search of MEDLINE, Embase, LILACS and Web of Science will be conducted without language or publication date restriction. Cross-sectional diagnostic studies of negative or sputum-scarce adults with presumptive PTB who underwent bronchoscopy to obtain samples for Xpert MTB/RIF and culture will be included. Screening and data extraction will be performed independently. Methodological quality will be assessed using the QUADAS-2 tool. A bivariate hierarchical random-effects model will synthesise sensitivity and specificity. Meta-analysis will be performed using Meta-DiSc 2.0. Heterogeneity will be assessed using <i>I</i> ^<i>2</i> and Cochrane thresholds. Subgroup analyses will be performed based on study design, population differences, country, culture method and risk of bias. Publication bias will be investigated using a funnel plot. The certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. There was no patient or public involvement in the development of the systematic review protocol. Ethical approval is not required as this study will use publicly available data. Findings will be disseminated through peer-reviewed publication. CRD42025639440.