Isolated Primary Tuberculosis of the Pectoralis Major Muscle

Abstract

Skeletal muscle tuberculosis is an extremely rare form of extrapulmonary TB, accounting for <1% of all cases, even in TB-endemic countries. We present the case of a 45-year-old female with isolated involvement of the right pectoralis major muscle, presenting as a painful, gradually enlarging anterior chest wall swelling. Computerized tomography scan revealed a soft tissue lesion within the muscle, and fine needle aspiration cytology from the lesion confirmed tuberculosis with granulomatous inflammation and acid-fast bacilli. The patient responded completely to standard anti-tuberculosis therapy. This case highlights the importance of considering tuberculosis in the differential diagnosis of soft tissue swellings at any site of body in endemic areas.