Abstract
Causative factors of toxic megacolon are predominantly ulcerative colitis, Cytomegalovirus colitis and pseudomembranous (CMV) enteritis. We experienced a case of toxic megacolon in a patient under the treatment of HIV infection, whose toxic megacolon appeared to be caused by neither of the above factors.
A 27-year-old man who had been followed for HIV infection developed fever, watery diarrhea and abdominal pain. Due to decreased CD4+146/μL, treatment with HAART was started. CMV, amebic enteritis or bacterial enteritis was likely, but the therapy was in effective. High fever, tachycardia, anemia, psychiatric symptoms, and electrolyte abnormalities were observed. Abdominal CT revealed expansion of the colon. Worsening of ulcerative lesions was suggested in endoscopic findings of the colonic mucosa. Toxic megacolon resistant to medical therapy was diagnosed, and surgical resection (ileostomy+subtotal colectomy) was performed. Immediately after the surgery high fever decreased and the patient regained his health. Factors for the development of toxic megacolon in this patient might be exacerbation of HIV infection itself or the immune reconstitution syndrome.
