When leprosy mimics tuberculosis: A diagnostic challenge between lepromatous leprosy and pulmonary tuberculosis in an indigenous community – A case report

ABSTRACT

Lepromatous leprosy can pose a significant diagnostic challenge in endemic regions where tuberculosis is also prevalent. We report the case of a 64-year-old Orang Asli Temuan man from Kuala Kubu Bharu, Hulu Selangor, Selangor, initially misdiagnosed with pulmonary tuberculosis following a positive sputum acid-fast bacilli (AFB) smear. The patient presented with grade 2 leprosy-related deformities including nasal cartilage destruction, autoamputation of the digits over the bilateral hands and feet with chronic ulcers and leonine facies. Slit-skin smear demonstrated a high bacteriological index (2.7), while his chest radiograph was inconclusive. Despite initial sputum AFB positivity, GeneXpert MTB/RIF and mycobacterial cultures repeatedly showed negative findings. These findings were attributed to bacillary shedding from the upper airway, a known but under-recognised phenomenon in multibacillary disease. The case highlights the risk of diagnostic confusion between leprosy and tuberculosis when relying solely on smear microscopy. Anti-tuberculous therapy and multidrug therapy (MDT) were temporarily withheld due to drug-induced liver injury. Pulmonary tuberculosis was excluded via negative rapid molecular testing and thoracic CT, and MDT was restarted. This case underscores the importance of confirmatory molecular testing, early diagnosis and culturally sensitive public health measures in indigenous communities affected by ongoing leprosy transmission.