Granulomatous mastitis: difficult to differentiate from tuberculous mastitis

Background: Granulomatous mastitis (GM) is a rare, chronic inflammatory breast disease of unknown etiology, characterized by controversial treatment options and a high recurrence rate. Its clinical and radiological presentation often overlaps with other conditions, particularly tuberculous mastitis (TBM), making differentiation challenging. This study aimed to differentiate granulomatous mastitis from tuberculous mastitis in patients presenting with chronic breast abscess. Methods: A prospective observational study was conducted at the Department of Surgery, Mugda Medical College Hospital, Dhaka, Bangladesh, from January to December 2023. Twenty women with symptoms and signs of breast abscess were selected from outpatient and inpatient departments. Each case underwent triple assessment: clinical evaluation, imaging and histopathology. Results: Among the 20 cases, 16 were diagnosed as non-lactational bacterial abscesses, 3 as granulomatous mastitis and 1 as tuberculous mastitis. Non-lactational abscesses healed with scarring within six weeks. All three GM cases recurred within five months; one developed steroid-related complications and two developed painful breast lumps after treatment. The single TBM case recurred after six months, with associated breast deformity and pain. Conclusions: Granulomatous mastitis is difficult to treat and clinically mimics tuberculous mastitis. Accurate diagnosis requires histopathological confirmation alongside clinical and imaging assessment to guide appropriate therapy.