P1221 - Myxedema Pseudo-Volvulus: A Rare Cause of Acute Colonic Pseudo-Obstruction

Garvit Chhabra, MD¹, Matthew A. Heckroth, MD¹, Amal Shine, MD¹, Dipendra Parajuli, MD^2
1University of Louisville, Louisville, KY; ²University of Louisville School of Medicine, Louisville, KY

Introduction: Acute colonic pseudo-obstruction is a condition characterized by acute colonic dilatation in the absence of mechanical obstruction. We present a case of severe hypothyroidism resulting in diffuse colonic pseudo-obstruction and partial sigmoid volvulus, a rare condition known as myxedema pseudo-volvulus.

Case Description/Methods: A 57-year-old male with a history of hypothyroidism presented with progressively worsening generalized swelling, shortness of breath, hoarseness, and severe constipation. Vitals were unremarkable except a heart rate of 56/min, and physical exam revealed periorbital swelling, hoarseness, and anasarca. The abdomen was distended and tympanic to percussion, without guarding or rebound tenderness. Labs showed TSH of 74.9 and fT4 < 0.25. CT revealed a large colonic stool burden with a transition point at the sigmoid colon with a mesenteric twist, concerning for a partial sigmoid volvulus. A bedside rigid proctoscopy was performed with placement of a rectal decompression tube and a follow-up CT scan revealed persistent, dilated stool-filled colon and narrowing at the sigmoid colon. He was restarted on 100mcg of levothyroxine daily with gradual improvement of transitory tone. Due to high fecal impaction with partial volvulus, sigmoidoscopy with follow-up colonoscopy was performed which revealed high stool burden and normal colonic mucosa without evidence of obstruction. Bowel function gradually improved after continued levothyroxine supplementation and colonoscopic fecal washout.

Discussion: Myxedema pseudo-volvulus is an extremely rare complication of hypothyroid crisis. Loss of bowel transitory tone secondary to hypothyroidism results in decreased peristalsis and increased bowel wall edema. Motility dysfunction from hypothyroidism has been well documented, however, progression to more severe manifestations such as acute ileus, pseudo-obstruction, and volvulus have been rarely discussed. Myxedematous deposits in the bowel wall muscle fibers lead to their separation from ganglia, affecting bowel motility. Hypothyroid-induced neuropathy can also affect the Auerbach’s and Meissner’s plexus, further aggravating intestinal hypomotility. Some peristaltic activity is usually recoverable with T4 supplementation however, in severe cases, atony may be irreversible and can lead to acute ileus, ischemia, or complete volvulus, requiring emergent surgical intervention. A high level of suspicion and prompt diagnosis can lead to successful nonoperative management.


Disclosures:


Garvit Chhabra, MD¹, Matthew A. Heckroth, MD¹, Amal Shine, MD¹, Dipendra Parajuli, MD². P1221 - Myxedema Pseudo-Volvulus: A Rare Cause of Acute Colonic Pseudo-Obstruction, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.