Application of Loop-Mediated Isothermal Amplification for Rapid Tuberculosis Diagnosis in Low-Resource Settings in Zamfara State

Rapid and accurate tuberculosis (TB) diagnosis remains a critical challenge in low-resource settings where laboratory infrastructure for conventional culture and GeneXpert testing is limited. This applied diagnostic study evaluated the performance of loop-mediated isothermal amplification (LAMP) as a point-of-care molecular diagnostic tool for TB detection in Zamfara State, in the North West geopolitical zone of Nigeria. Sputum samples from 180 patients with clinical suspicion of pulmonary TB attending chest clinics in Gusau and Kaura Namoda were tested using LAMP, Ziehl-Neelsen smear microscopy, and the WHO-endorsed GeneXpert MTB/RIF assay as the reference standard. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for LAMP and smear microscopy against the GeneXpert reference. LAMP demonstrated sensitivity of 92.3 percent and specificity of 96.4 percent compared to GeneXpert, significantly outperforming smear microscopy which had sensitivity of 63.1 percent. LAMP results were obtained within 60 minutes per test run. Cost per test analysis indicated LAMP to be significantly less expensive than GeneXpert per diagnosis. The study concludes that LAMP represents a highly promising decentralized TB diagnostic tool for Zamfara State's peripheral health system and recommends its integration into state-level TB control programs, with parallel strengthening of laboratory supply chains. Keywords: LAMP, tuberculosis diagnosis, Zamfara, point-of-care diagnostics, GeneXpert.