Life-Threatening Hypokalemia and Ventricular Arrhythmia Secondary to Segmental Colitis Associated With Diverticulosis: A Case Report.

Segmental colitis associated with diverticulosis (SCAD) is a localized inflammatory condition involving colonic segments affected by diverticulosis, most commonly the sigmoid colon. It is typically considered a benign entity presenting with mild hematochezia or intermittent diarrhea, with systemic complications rarely reported. We present a 47-year-old male with a history of autoimmune disease and chronic high-volume diarrhea who presented with chest pain and dyspnea. On admission, he was found to have profound hypokalemia with electrocardiographic abnormalities. His course was complicated by non-sustained ventricular tachycardia in the setting of underlying structural heart disease. An extensive infectious and inflammatory workup was unrevealing. Colonoscopy demonstrated sigmoid diverticulosis with localized peri-diverticular erythematous mucosa and rectal sparing, consistent with SCAD. Following aggressive electrolyte repletion and antibiotic therapy, the patient's metabolic abnormalities resolved, and diarrhea improved. This case expands the clinical spectrum of SCAD by demonstrating that chronic inflammatory diarrhea may result in severe electrolyte depletion and life-threatening arrhythmias. Clinicians should consider SCAD in the differential diagnosis of chronic diarrhea, particularly when associated with unexplained electrolyte disturbances.