P3.R355: Hip Pain as a Manifestation of Pediatric Endocarditis: A Case Report

Introduction: A 10-year-old male with past medical history of pulmonary stenosis s/p surgical repair as a young child presents with a six-week history of anterior left hip pain. His mother states that he initially developed a low-grade fever followed by left ankle and groin pain. His fever and ankle pain resolved but his groin pain had persisted. He was initially seen at an urgent care and now presents as a referral to pediatric sports medicine.

Case Description: The patient’s mother denies any recurrent fevers, stiffness, early morning pain, nighttime symptoms, weight loss, eye, throat, or abdominal pain. His examination was notable for left hip pain to palpation and inability to perform hip flexion and abduction, but was otherwise unremarkable. Initial x-rays of the left hip obtained at urgent care were unremarkable. He was sent for blood work and an MRI. Initial blood work revealed leukocytosis (WBC 11.9) with neutrophilic predominance and elevated inflammatory markers (ESR 28, CRP 11). MRI L hip demonstrated left-sided sacroiliitis but was also concerning for a sacral abscess on independent review (Figure 1). He was subsequently treated with a 10-day course of Augmentin. Repeat blood work 4 weeks later was notable for a normal CBC but persistently elevated inflammatory markers (ESR 22, CRP 34), and he was referred to both pediatric rheumatology and infectious diseases. Rheumatology workup was largely unremarkable including a normal uric acid level, as well as negative Lyme titers, HLA-B27, and fecal calprotectin. Given his cardiac history, an echocardiogram was obtained which demonstrated endocarditis. He was subsequently admitted to Johns Hopkins. During hospitalization, blood cultures grew Streptococcus viridans, and a chest CT revealed septic emboli to the lungs (Figure 2A-B). The patient was ultimately discharged home on IV penicillin through a PICC line.

Discussion: Infective endocarditis is an infection of the endocardium and/or heart valves that involves vegetation formation. It is a rare condition among children in the United States (incidence of 0.3 to 3.3 per 100,000 individuals per year). Risk factors include history of congenital heart disease, indwelling central venous catheters, and rheumatic heart disease. In its subacute form, patients may present with recurrent fevers, fatigue, arthralgias, myalgias, weight loss and exercise intolerance. Initial laboratory workup usually includes CBC, ESR/CRP and blood cultures. EKG and CXR may be obtained, but these are often nonspecific. Diagnosis is confirmed with a positive blood culture and echocardiogram. Management of pediatric endocarditis is with IV antibiotics for 4 weeks.

Conclusion: Infective endocarditis is a rare condition in children but can pose significant morbidity and mortality. This case report reinforces that medical conditions may often present with musculoskeletal complaints, and sports medicine providers must always include a broad differential when patients are not improving.