West Nile Virus Meningoencephalitis during Treatment of Crohnʼs Disease with Adalimumab

Abstract

Purpose: A 72-year-old male with longstanding history of ileocolic Crohn's disease presented with one week of high grade fevers, fatigue, headache and declining mental status. The patient was diagnosed with inflammatory bowel disease 23 years prior and for two decades was stable on a regimen which included 6-mercaptopurine (6-MP) and mesalamine. Two years prior to admission he developed worsening diarrhea and following a colonoscopy showing active colitis was started on Infliximab and steroids. Symptoms improved however recurred upon steroid taper. Infliximab therapy was escalated and he was transitioned from 6-MP to Methotrexate with improvement, but incomplete disease control. Due to ongoing symptoms patient was switched to adalimumab, which was later escalated to 80 mg every other week. Patient was having 8-9 solid bowel movements daily at the time of admission. On presentation the patient's systolic blood pressure was greater than 200 mmHg. Brain imaging did not reveal any acute changes. He was admitted to the ICU where blood pressure was stabilized and broad spectrum antibiotics were initiated, however his mental status continued to decline. He underwent lumbar puncture which was notable for opening pressure of 160 mmHg, consistent with aseptic meningitis. He was started on acyclovir but continued to deteriorate; within days he developed septic shock and respiratory failure secondary to MRSA pneumonia. Electroencephalogram demonstrated nonspecific slowing and extensive infectious work up resulted in serology positive for West Nile virus. Despite supportive efforts, his condition worsened over a 3 week period and per the family's wishes he was palliatively extubated. It was later discovered that the patient was bitten by a mosquito while gardening shortly before admission. The introduction of anti tumor necrosis factor alpha (TNF α) therapy in the late 1990s significantly expanded the armamentarium for the management of IBD. These agents have proven effective in treating Ulcerative colitis and Crohn's disease and thus their use has become common practice. Unfortunately, treatment related infections are known to occur. In vitro studies have demonstrated a neuroprotective role of TNF α in West Nile virus infection. Inhibitors of the TNF α response thus theoretically prolong viremia and increase penetration into the CNS. Here we describe a case of fatal West Nile virus meningoencephalitis in the setting of Crohn's disease treatment with adalimumab. A heightened awareness of mosquito-borne infections and monitoring for early symptoms of West Nile virus infection are encouraged for patients receiving anti TNF α therapy because of theoretically increased susceptibility to severe disease.