DOI: https://doi.org/10.36347/sjmcr.2025.v13i10.111

Pages: 2647-2649

Introduction: Idiopathic granulomatous mastitis (IGM) is a rare, benign, chronic inflammatory breast disease of unknown etiology, predominantly affecting women of reproductive age. Its variable clinical presentation and unpredictable course make it a persistent diagnostic and therapeutic challenge. Case presentation: We report the case of a 41-year-old woman presenting with a painful, erythematous nodule in the left breast, complicated by cutaneous fistulization and purulent discharge. Microbiological cultures were sterile. Breast ultrasound revealed a 20 × 18 mm hypoechoic lesion with multiple perilesional abscesses (BIRADS 4A). Core needle biopsy demonstrated granulomatous inflammation without caseous necrosis or malignancy. A comprehensive etiologic workup was unremarkable. The diagnosis of IGM was established, and oral corticosteroid therapy (60 mg/day) was initiated, leading to marked clinical improvement. The dose was gradually tapered, with no recurrence observed after 15 months of follow-up. Discussion and conclusion: IGM should be considered in reproductive-age women presenting with inflammatory breast masses after exclusion of infectious and autoimmune causes. Histopathology remains essential for diagnosis. While management is still debated, corticosteroid therapy is the preferred first-line approach. Surgery should be reserved for complicated or refractory cases. A conservative,