Tuberculous mastitis, the great imitator in breast disease: a case report with diagnostic and therapeutic challenges

Background Extrapulmonary tuberculosis (TB) remains a diagnostic challenge due to its nonspecific clinical manifestations, low bacterial burden, and the need for invasive procedures to obtain diagnostic samples. Breast TB, a particularly rare form, can closely mimic other conditions such as inflammatory breast carcinoma. Case presentation A 30-year-old Peruvian woman with no relevant medical history was admitted with painful erythema of the right breast and two fistulous tracts secreting purulent discharge. Initial microbiological tests, including interferon-gamma release assay (IGRA) and cultures, were negative. Imaging revealed multiple pulmonary micronodules, and breast biopsy demonstrated granulomatous inflammation with Langhans giant cells. Despite negative PCR and culture results for mycobacteria, empirical antitubercular therapy was initiated based on clinical, radiological, and histopathological evidence. The patient was initiated on standard antitubercular therapy, which was simplified two months later. Progressive clinical improvement was observed, with complete ulcer healing by month 4 and resolution of pulmonary nodules by month 7. By month 12, she remained in good clinical condition with no signs of recurrence. Conclusions This case highlights the diagnostic complexity of breast TB and underscores the importance of a multidisciplinary approach in the absence of microbiological confirmation. Clinical context, imaging, and histology may guide successful empirical treatment and improve patient outcomes.