Brainstem CMV encephalitis in AIDS: clinical case and MRI features

Atypical presentation and diagnosis of AIDS-related CMV encephalitis

We report a case of man in his 40s with a medical history of post-traumatic stress disorder who presented to the emergency department with altered mental status, ataxia, headache and dizziness a few hours after snorting amphetamines and mushrooms. Twenty-four hours after presentation, while no longer abusing amphetamines or mushrooms, he remained ataxic and dizzy. A CT scan of the head showed periventricular hypodensities. MRI of the brain revealed extensive confluent T2 hyperintense signal throughout the cerebral white matter, brainstem and cerebellar white matter. Given these findings and persistent ataxia, lumbar puncture was performed, and cerebrospinal fluid (CSF) meningoencephalitis panel was positive for cytomegalovirus (CMV), prompting a diagnosis of CMV encephalitis. Since CMV almost always occurs in the setting of immunocompromise, the patient was screened for HIV and found to be positive with a CD4 count of 22. He was treated with ganciclovir 5 mg/kg/dose intravenously every 12 hours, with resolution of all symptoms.

Magnetic resonance imaging of mesenrhombencephalitis

Mesenrhombencephalitis is a rare inflammatory process involving the midbrain, pons, and medulla. The diagnosis is difficult as clinical and laboratory findings may be nonspecific. Magnetic resonance (MR) imaging demonstrates abnormal T2 signal in the brainstem, which can suggest the diagnosis. The clinical, laboratory and MR imaging findings are described in five patients with this serious, life-threatening disease. MR imaging can be of value in the early diagnosis of this rare disorder.