BK VIRUS ENCEPHALITIS IN AN IMMUNOCOMPETENT PATIENT

Objectives: To describe a previously healthy patient now suffering fro m monophasic encephalitis caused by a primary infection with BK virus and to discuss possible risk factors for developing BK virus encephali tis. Design: Case report. Setting: Referral hospital. Patient: The pat ient was examined on referral. Main Outcome Measures: The main diagnos tic tests performed were serology, polymerase chain reaction on cerebr ospinal fluid samples, and cranial magnetic resonance imaging. Results : During the course of the patient's encephalitis, an IgM titer develo ped against polyomavirus, followed by anti-polyomavirus IgG. Wild-type BK virus was demonstrated in cerebrospinal fluid samples. Cranial mag netic resonance imaging showed diffuse reversible white matter changes most prominent on T-2-weighted images. Conclusion: We conclude that d iagnostic tests for BK, a human polyomavirus, should be included in th e screening program for encephalitogenic pathogens.