Steroid-responsive Encephalopathy with a Primary CMV Infection Complicated by Enteritis in a Young Woman with Ulcerative Colitis.

A 23-year-old woman with ulcerative colitis (UC) presented with fever, headache, an altered mental status, and bloody stool. A neurological examination, magnetic resonance imaging, and electroencephalography revealed right-side dominant encephalopathy. Although a serological analysis revealed a primary cytomegalovirus (CMV) infection, the cerebrospinal fluid (CSF) showed no evidence of a viral load, although the CSF interleukin-6 levels were markedly elevated (1,670 pg/mL). Encephalopathy rapidly improved with steroid therapy; however, the presence of bloody stool persisted. A colon biopsy revealed concurrent CMV enteritis, which improved with ganciclovir. This case shows that steroid-responsive encephalopathy can occur during a primary CMV infection. Additionally, CMV enteritis complicated by a primary CMV infection should be considered in patients with UC.