Acute Cerebellar Ataxia as the Presenting Symptom of Progressive Multifocal Leukoencephalopathy with HIV - A Case Report.

A 45-year-old man presented with acute onset ataxia for last 1 week. On examination he had signs of left-sided cerebellar involement. MRI brain revealed asymmetric altered signal intensities in bilateral cerebellar hemispheres suggesting demyelinating lesions. ELISA for Human Immune Deficiency virus-1 was positive. CSF JC virus DNA PCR was positive. A diagnosis of Progressive Multifocal Leukoencephalopathy (PML) was made on the basis of clinico-radiological picture and JC virus DNA PCR presence in CSF. PML is unknown and under diagnosed CNS infection seen in HIV patients mostly seen with advanced disease. We present an unusual case report where isolated cerebellar involvement occurred as the first AIDS defining event in the absence of appreciable immunodeficiency in a patient with previously undiagnosed HIV infection.