Abstract
McKittrick-Wheelock syndrome is characterized by fluid deficit, electrolyte derangements, and acute kidney injury caused by a villous colorectal polyp. Treatment depends on both the location and size of the polyp. Most small polyps are treated by endoscopic resection and larger polyps by either surgical segmental resection or endoscopic excision. The most challenging polyps are those involving the lower rectum, often associated with rectal prolapse. Endoscopic excision is much more difficult, and surgical resection remains the predominant treatment option. We discuss an 83-year-old female with a large low rectal polyp who is presenting with "chronic diarrhea," electrolyte deficiencies, acute-on-chronic kidney disease, hypoalbuminemia, and anemia. Clinical assessment, colonoscopy, radiological imaging, and histological diagnosis were consistent with a large tubulovillous adenoma with low-grade dysplasia. After physiological optimization, the lesion was successfully treated by transanal submucosal excision and Delorme's plication, instead of an abdominoperineal resection; there was a prompt resolution of the symptoms. A patient with the triad of chronic diarrhea, acute renal insufficiency, and electrolyte deficiencies should have a colonoscopy to rule out a villous colorectal polyp. Low rectal polyps that are too large to be resected endoscopically could benefit from transanal excision and Delorme's plication, instead of an abdominoperineal resection.