VIPoma: An Unusual Cause of Chronic Diarrhea.

Chronic diarrhea is a significant challenge in clinical practice because of its high prevalence and various causes. Comprehensive clinical assessment and stepwise laboratory approach are crucial for an accurate diagnosis. This report presents a case of an adult woman who experienced chronic watery diarrhea, complicated by renal impairment and multiple electrolyte imbalances, including hypokalemia, hypophosphatemia, and metabolic acidosis. The diagnosis of a vasoactive intestinal polypeptide-secreting tumor (VIPoma) with liver metastases was confirmed by elevated serum levels of a vasoactive intestinal polypeptide (VIP) and imaging findings of a pancreatic mass with multiple hepatic lesions. Preoperative management, including fluid rehydration, electrolyte correction, and somatostatin analog therapy, significantly improved her clinical symptoms. Subsequent surgical tumor removal and radiofrequency ablation of the hepatic lesions resulted in complete resolution of symptoms and normalized VIP levels. This case emphasizes the importance of early recognition of this rare tumor in patients with chronic diarrhea to improve clinical outcomes.