P0644 - From Father to Daughter: A Rash Portending a Deeper Diagnosis

A 12-year-old healthy female presented to her pediatrician with 4 months of painful, deep purple rashes on the hands and feet, appearing intermittently for 1-7 days at a time. She denied pruritus or triggers, such as temperature changes or contact exposures. She was diagnosed with hand-foot-mouth disease but her symptoms persisted, prompting referral to dermatology. A lesion was biopsied, and basic labs, including CBC, CMP, ESR, and CRP, were unremarkable. Rheumatology obtained anti-dsDNA, cardiolipin antibodies, anti-SS-A, anti-SS-B, Anti-Smith/RNP, anti-beta-2-glycoprotein, C3 and C4 complements, and dilute Russell’s viper venom time – these were unremarkable. The skin biopsy revealed a vessel lumen occluded by myxoid material, concerning for an embolic process possibly secondary to cardiac myxoma. Upon sharing this information, family revealed a previously undisclosed family history significant for a father with Carney complex and cardiac myxomas. An echocardiogram was obtained, revealing a myxoma in the left atrium. She was admitted for surgical removal. At time of admission, she denied chest pain, palpitations, shortness of breath, or anasarca. The surgeon removed a 4.0 x 3.5 x 1.0 cm friable mass from the left atrium. Her post-operative course was complicated by post-pericardiotomy syndrome. At six-week follow-up, her echocardiogram showed normal cardiac anatomy and function.

Pediatric cardiac tumors are rare, with the most common benign primary cardiac tumor being rhabdomyomas. In adults, the most common benign primary cardiac tumors are myxomas. For this reason, current management of myxomas is guided by adult literature. Approximately 35% of myxomas are friable and villous. They present with emboli manifesting as neurologic or systemic symptoms, e.g. vasculopathy. Larger tumors tend to have smooth surfaces and present with cardiovascular symptoms reflective of obstructive physiology. In a review of 20 pediatric patients diagnosed with myxomas, 70% of patients presented with symptoms suggestive of embolization. While myxomas are typically spontaneous in adults, with average age-of-onset in the fifth decade of life, early onset in the first or second decade should raise concern for a familial cause, particularly Carney complex. Carney complex is an autosomal dominant syndrome that presents with pigmented skin, myxomas, and multiple endocrine tumors. Once the diagnosis is made, the myxoma should be resected to prevent sequela of emboli or sudden death. Currently, there is no consensus recommendation on anticoagulation for these patients. Surgical outcomes reveal less than 5% operative mortality. Postoperative complications may include arrhythmias or recurrence of myxoma.

This case highlights the need for a thorough family history to guide suspicion for cardiac myxomas in patients with systemic or neurologic symptoms of embolization or new onset cardiac symptoms. While cardiac myxomas are rare in childhood, early recognition is essential to urgently remove the myxoma, avoid preventable sequela including death, and begin timely genetic work-up in pediatric patients.