Brodie's Abscess in a Pediatric Patient: A Diagnostic Pitfall.

Brodie's abscess is a localized form of subacute osteomyelitis that often presents without systemic illness and may be misdiagnosed due to its indolent course. We describe a pediatric patient in whom Brodie's abscess initially mimicked a less severe, superficial condition, resulting in delayed definitive diagnosis. The patient was initially treated for presumed septic infrapatellar bursitis, with transient clinical improvement under antibiotic therapy before imaging revealed proximal tibial osteomyelitis consistent with a Brodie's abscess. This case highlights the risk of misdiagnosis in children presenting with atraumatic knee pain and underscores the importance of reconsidering initial diagnoses when clinical progression is atypical. Early and appropriate imaging is essential to avoid delayed diagnosis and potential complications.