Clinical spectrum of extrapulmonary non-tuberculous mycobacterial disease in immunocompetent patients: a case series

Non-tuberculous mycobacterial (NTM) disease is an underdiagnosed condition that usually manifests as pulmonary infection. Extrapulmonary manifestations are rare and can be easily overlooked or misdiagnosed as tuberculosis or malignancy.

Herein, we present four cases of extrapulmonary NTM disease in immunocompetent patients. Patient 1 had bone marrow suppression secondary to NTM infection. Patient 2 was diagnosed with Mycobacterium abscessus meningitis, brain abscess and arachnoiditis. Patient 3 had pleural effusion, and fluid cytology revealed Mycobacterium fortuitum. Patient 4 was a 30-year-old male with cervical lymphadenopathy due to NTM. Two patients (case 2 and case 4) were initially diagnosed with tuberculosis but showed no response to anti-tubercular drugs. One patient (case 3) died within seven days of initiation of treatment. The rest of the patients (cases 1 and 2) showed clinical improvement with antimicrobial therapy for NTM species. Case 4 responded well to surgical excision without the need for antibiotics.

Clinicians should be vigilant about the possibility of NTM disease. Early diagnosis is vital to prevent poor outcomes, particularly in the setting of disseminated infections.