[Focal presentation of progressive multifocal leukoencephalopathy: first manifestation of human immunodeficiency virus infection].

INTRODUCTION: Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating disorder of central nervous system caused by an opportunistic papovavirus infection of oligodendroglial cells, the JC virus. This virus remains latent in the human host. Their antibodies are detectable in 70% of healthy adult subjects. It is reactivated by different diseases and medical therapies impairing cellular immunity. CLINICAL CASE: A 35 year-old man, smoker, allergic to penicillin and derivatives, with a history of endovenous drug abuse, was admitted to Neurology Department due to a progressive left facial palsy and hand weakness. An alteration in the cellular immune ratio (CD4/CD8 0.07) and a positive human immunodeficiency virus serology were demonstrated. Highly active antiretroviral therapy (HAART) was started. A unique wide hyperintense subcortical right temporoparietal lobe lesion was shown by a cerebral magnetic resonance imaging (MRI), suggesting a differential diagnosis between PLM and low grade glial tumor. Cerebrospinal fluid study was normal and the polymerase chain reaction (PCR) was negative for JC virus. A steroataxic cerebral biopsy was made in order to establish a correct diagnosis due to patient's age and the good response to treatment. The pathology study showed changes suggestive of PLM and a positive-PCR test for JC virus. DISCUSSION: We report this case to suggest that inva- sive diagnosis methods may be useful to differentiate between PLM and low grade glial tumors and to establish a correct prognosis. HAART is becoming a good treatment option because it seems to make long term survival longer, as is the case of this patient who is practically asymptomatic after more than 2 years of evolution.