Diagnostic Accuracy and Yield of Determine Urine TB LF-LAM for Detecting Tuberculosis Among Adults and Children with Advanced HIV Disease in Nigeria.

IntroductionTuberculosis (TB) diagnosis remains the weakest link in the care cascade, particularly among people living with HIV and AIDS (PLHIV) with advanced HIV disease (AHD), who are often cannot produce quality sputum for standard tests. Urine-based assays such as Determine Urine TB LF-LAM(R) offer a non-invasive, easy-to-collect alternative that can detect lipoarabinomannan antigen even in extrapulmonary TB, making them especially useful in severely immunocompromised individuals. MethodsWe conducted a cross-sectional diagnostic accuracy and yield of Determine Urine TB LF-LAM(R) against GeneXpert MTB/RIF as the reference standard among adults and children (<5 years) with AHD enrolled across 334 selected HIV treatment facilities in Nigeria between July 2022 and July 2025. We calculated the DY for LF-LAM among all AHD patients tested and, in the paired-testing cohort, determined its incremental diagnostic yield (IDY). Test proportions are presented with 95% CIs using the Wilson score method; discordance in paired results was assessed with McNemars test. ResultsOf the 17,155 AHD patients tested with LF-LAM on first urine samples, 5,212 were TB LF LAM positive, giving a diagnostic yield of 30.4%. Among 5,212 LF LAM positives, 2,074 (41%) of them were not presumptive through WHO four-symptom screening and would have been missed without LF-LAM. Among 3,138 patients tested with both GeneXpert and LF-LAM, GeneXpert detected 1,914 TB cases. The remaining 1224 GeneXpert-negative cases tested positive through TB LF-LAM, giving an incremental yield of 39% for LF-LAM over GeneXpert (1224/(1,914+1224); Wilson 95% CI) with significant discordance (McNemar p<0.001). ConclusionDetermine Urine TB LF-LAM(R) substantially improved TB case detection among PLHIV with AHD in routine Nigerian HIV programs, including pediatric and severely immunocompromised patients who are unable to produce sputum or with extrapulmonary TB. Its high incremental yield and simplicity underscore the need for programmatic integration of LF-LAM with molecular testing to close diagnostic gaps and reduce TB-related mortality. Summary BoxO_ST_ABSWhat is already known about this topic?C_ST_ABSO_LITuberculosis (TB) is the leading cause of death among people living with HIV (PLHIV), contributing to approximately 35% of opportunistic infections among those with advanced HIV disease (AHD). C_LIO_LIConventional TB diagnosis in PLHIV relies on sputum-based tests such as GeneXpert MTB/RIF, which are often limited by poor sputum production in immunocompromised individuals and reduced sensitivity in extrapulmonary TB. C_LIO_LIThe World Health Organization recommends urine-based TB lipoarabinomannan (LF-LAM) testing for PLHIV with AHD, but programmatic evidence from Nigeria remains scarce. C_LI What this study addsO_LIThis study provides further insight on the diagnostic accuracy and yield of Determine Urine TB LF-LAM(R) among adults and children with AHD in Nigeria in a real programmatic setting. C_LIO_LIIt demonstrates the added diagnostic value of urine-based LF-LAM testing in immunocompromised patients, including those unable to produce sputum or with extrapulmonary TB. C_LI How this study might affect research, practice or policyO_LIFindings support integrating LF-LAM into the routine AHD care package in Nigeria and similar high-burden, resource-limited settings. C_LIO_LIEvidence from this study can inform national HIV and TB program guidelines and accelerate scale-up of non-invasive TB diagnostic strategies to reduce TB-related mortality. C_LI