DISCUSSION
Historically, clinical manifestations of BT have been observed within 1 year, but they range from months to years.11 BT commonly affects women aged from 20-50 years,4,12which is equivalent to the higher prevalence of pulmonary tuberculosis seen in a similar age women.13 In our report, the patient was a 34-year-old woman presenting with symptoms for 2 months.
BT regularly presents as a lump14 in the central or upper outer quadrant of the breast.15 In our patient, the lump was present in the upper outer quadrant of the right breast. Manifestation is inconsistent, frequently as a round nodular lump with tissue induration, with fistula formation, but they are infrequently connected with pain. Our patient had diffuse ulceration, pain, and a lump in the right breast.
Tubercular ulcers over the breast skin and tubercular breast abscess with or without discharging sinuses are even common forms of presentation of BT.13 Our patient presented with a unilateral draining sinus.
BT was classified earlier as: Nodular, disseminated, sclerosing, obliterans, and acute miliary tubercular mastitis.14The sclerosing, obliterans, and miliary types are of historical significance and currently BT could be reclassified as nodular, disseminated, or abscess. The BT in our patient belonged to the abscess variety.
BT lesions have no specific US findings and are visualized as heterogeneous, hypoechoic, irregularly bordered with internal echoes.16 Diagnosis is optimally based on the confirmation of AFB in the breast tissue by ZN staining.17 In this study, Doppler US showed features of breast abscess, while FNAC showed epithelioid granulomas with AFB positivity on ZN staining.
FNAC is a trustworthy diagnostic procedure, in which aspirated material is subjected to staining for revealing AFB18 and diagnosing BT.17 In BT cases, FNAC evaluation has accurately diagnosed the cases as BT in 73% of the cases evaluated using histopathology as having both epithelioid granulomas and necrosis.19 In this study, histology revealed the presence of Langhans giant cells, epithelioid cell granulomas, and caseous necrosis; FNAC was diagnostically useful for BT.
Trepan biopsy showed a decent positive result. However, inci-/excisional biopsy of breast lumps, ulcers, and sinuses, or a suspected tubercular breast abscess cavity wall mostly diagnoses BT.17,19In this patient, an excision biopsy was suggested, but the patient and her attendants refused the procedure.
Even though tests such as QuantiFERON‐TB Gold-In tube have high sensitivity (97.9%) and specificity (98.1%),20 there are many limitations such as false-negative results in extrapulmonary tuberculosis (28.8%)21 and inability to discriminate latent tuberculosis from active tuberculosis infection.22 In this study, FNAC evaluation paved the way for an accurate diagnosis.
BT could show a diagnostic difficulty in radiological and microbiological diagnosis, and consequently, high degree of suspicion are required. BT is treatable with ATT,23 and surgical intervention is needed in rare situations.