Pheochromocytoma multisystem crisis presenting with abdominal pain in an adolescent: a case report

BACKGROUND: Pheochromocytoma is a rare neuroendocrine tumor in children, typically presenting with hypertension, headache, and palpitations. Presentation with abdominal pain as the sole initial symptom, rapidly progressing to catecholamine-induced cardiomyopathy, cardiogenic shock, and multiple organ dysfunction syndrome (MODS), is exceedingly uncommon and poses significant diagnostic and therapeutic challenges. We report a case of adolescent pheochromocytoma multisystem crisis to highlight the diagnostic pitfalls, pathophysiological cascade, and the dilemma of extracorporeal life support. CASE PRESENTATION: A 13-year-8-month-old male presented with a 3-day history of abdominal pain and poor responsiveness. Initial treatment for acute gastroenteritis was ineffective, and his condition rapidly deteriorated into cardiogenic shock and multiple organ failure, requiring mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) prior to transfer to our hospital. The clinical course was characterized by sustained abdominal pain as the initial manifestation, absence of typical palpitations or headache, transient hypertension (175/109 mmHg) followed by circulatory collapse, and physical findings of a sedated state, mottled skin with extremity ecchymoses, muffled heart sounds, absent bowel sounds, and prolonged capillary refill time of 5 s. Bedside echocardiography revealed a left ventricular ejection fraction of only 26%. Abdominal computed tomography and ultrasonography demonstrated a left adrenal mass. Plasma normetanephrine was markedly elevated at > 20.56 nmol/L (normal ≤ 0.9 nmol/L) and 3-methoxytyramine at 5.47 nmol/L (normal < 0.18 nmol/L), confirming the diagnosis of pheochromocytoma. VA-ECMO and mechanical ventilation were maintained. Multiple sessions of plasma exchange and continuous renal replacement therapy were instituted, alongside vasoactive agents. Surgical resection was planned but never performed due to progressive multiorgan deterioration. Despite 6 days of ECMO support and comprehensive therapy, the patient developed hepatic encephalopathy and digital dry gangrene. The family elected to withdraw care, and the patient died shortly after discharge. CONCLUSIONS: This case illustrates that pheochromocytoma can present with abdominal pain as the sole initial symptom in adolescents, mimicking acute gastroenteritis. The rapid progression from catecholamine storm to irreversible multiorgan failure underscores the critical importance of early recognition of atypical presentations. While VA-ECMO may serve as a bridge to diagnosis and stabilization, it cannot reverse established multiorgan injury when timely surgical source control is not achieved.