Xanthogranulomatous osteomyelitis of pubic bone mimicking neoplasm: a case report and literature review.

Background: Xanthogranulomatous osteomyelitis (XO) is a rare disease characterized radiologically by an osteolytic lesion with cortical expansion or disruption. Differentiating this condition from other osteolytic diseases such as primary or metastatic bone neoplasms is imperative. Several case reports have been published on XO, with previous reports predominantly identifying bacteria such as Pseudomonas or Staphylococcus as causative organisms. However, fungal infection-induced XO has not yet been reported.
Case Presentation: We present the case of a 23-year-old woman with a tumor-like osteolytic lesion in the pubic bone. The patient had experienced pelvic pain and intermittent febrile episodes for 2 months. Plain radiography revealed an osteolytic lesion in the right pubic tubercle. Magnetic resonance imaging suggested a cystic bone tumor or tubercular infection. Surgical intervention included curettage of the lesion and irrigation with normal saline. Histopathological examination of the specimen revealed abundant foamy histiocytes with inflammatory infiltrates consistent with XO. Culture of the osteolytic lesion confirmed an Aspergillus species infection and antifungal treatment was initiated. At 1-year follow-up, no evidence of local recurrence was observed.
Conclusions: Although rare, XO requires differentiation from similar conditions and is treated with surgical intervention and targeted medical therapy based on the identified organisms. Clinicians should be mindful that XO can also be induced by fungal infections and that combination antifungal treatments may be beneficial in such cases.
(© 2024. The Author(s).)