Which combination of findings establishes the diagnosis of toxic megacolon in a patient with severe ulcerative colitis?

• A Colonoscopic evidence of deep ulceration irrespective of colonic diameter
• B Cecal diameter greater than 12 cm in a postoperative patient without colitis symptoms
• C Diffuse colonic dilation on CT in a patient taking loperamide alone
• D Transverse colon diameter greater than 6 cm on plain radiograph together with systemic toxicity such as fever, tachycardia and leukocytosis ✓

Explanation

Toxic megacolon requires both radiological colonic dilation, classically a transverse colon exceeding 6 cm, and evidence of systemic toxicity including fever, tachycardia, leukocytosis or electrolyte disturbance in the setting of acute colitis. Option B describes Ogilvie syndrome, a pseudo-obstruction without mucosal inflammation, which is a different entity. Endoscopy is avoided in suspected toxic megacolon because insufflation risks perforation, so option A is incorrect.

Reference: Schwartz's Principles of Surgery, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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