An unusual case of Brodie's abscess in the humerus of an adult female

Abstract

Brodie's abscess is a manifestation of subacute to chronic osteomyelitis, characterized as intraosseous abscess formation, usually on the metaphysis of the long tubular bones in the lower extremities of male pediatric patients. Clinically, Brodie's abscess presents with atraumatic bone pain of an insidious onset, with absence of systemic findings. Delay in diagnosis is common, as diagnostic imaging, followed by biopsy for culture and histologic examination are generally required to secure a diagnosis of Brodie's abscess. Treatment of Brodie's abscess is non-standardized, and usually consists of surgical debridement and antibacterial therapy. Despite the variability in therapeutic approaches, outcomes of Brodie's abscess treated with surgery and antibiotics are favourable. Herein we report a case of a delayed diagnosis of Brodie's abscess in the upper extremity of an adult female. While she improved with treatment of Brodie's abscess, the case serves to remind clinicians to consider this entity in adult individuals who present with atraumatic bone pain.

Keywords: Brodie abscess; Humerus; Osteomyelitis; Staphylococcal infections; Staphylococcus aureus.

Fig. 1

Left humeral radiograph demonstrating central lucent lesion within the distal left humeral metaphysis measures 12 mm with surrounding ill-defined sclerosis and cortical thickening without fracture, periosteal reaction, or soft tissue component.

Fig. 2

Magnetic resonance imaging of A) Sagittal STIR, B) Sagittal T1-weighted, C) Coronal T-1 weighted post-gadolinium, and D) Axial T-1 weighted post-gadolinium demonstrating a eccentric distal left humeral metaphyseal lesion abutting the cortex with associated thickening, with T1 hypointense, T2 hyperintense signal with a thin T1 hyperintense rim suggestive of granulation tissue without intrinsic enhancement following administration of intravenous gadolinium. Abnormal edema and enhancement surround the lesion that extends into the periosteum and musculature without subperiosteal fluid collection, pathologic fracture, or soft tissue lesion.

Fig. 3

Biopsy of the left humeral lesion demonstrating A) lymphoplasmacytic (i.e. chronic) inflammatory infiltrate with deposition of reactive fibrous tissue in the marrow space, and B) fragments of lamellar bone with fibrin and mixed (i.e. acute and chronic) inflammatory cells including neutrophils, lymphocytes and plasma cells, suggestive of subacute osteomyelitis, both at 400 x magnification.