Pelvic Osteomyelitis in a Child - A Diagnostic Dilemma

INTRODUCTION: Pelvic osteomyelitis presents a diagnostic challenge due to its rarity and non-specific presentation. Early advance imaging in the form of magnetic resonance imaging (MRI) is warranted if clinical suspicion is high. We present an unusual case of pubic rami osteomyelitis, presenting with clinical findings of septic arthritis treated appropriately with early imaging and intravenous antibiotics with satisfactory outcome. CASE REPORT: A 9-year-old boy presented to accident and emergency with 2 days history of the left-sided groin and thigh pain, inability to weight bear, and feeling generally unwell following a rugby match. There was no history of trauma or recent infection. On examination, the child had fever, limp on weight-bearing, tender groin, and signs of an irritable hip. Laboratory report showed raised inflammatory markers and blood culture showed Staphylococcus aureus. Presumptive diagnosis of septic hip joint was made as there was effusion on ultrasound examination. Specialist opinion was sought and MRI confirmed changes of the left pubic rami osteomyelitis. The child was treated with intravenous antibiotics, with excellent clinical response after 48 h. CONCLUSION: Pelvic osteomyelitis in a child is a rare occurrence. This case highlights the significance of having a wide differential diagnosis for non-specific hip pain in a child. An MRI will help with the diagnosis if there is any uncertainty of the underlying cause. Early treatment with IV antibiotics is ideal for uncomplicated recovery. A multidisciplinary team approach is of utmost importance.