Progressive Multifocal Leukoencephalopathy in the Setting of Idiopathic CD4 Lymphocytopenia: Case Report and Literature Review of the Epidemiology (P2.075)

Objective: To report a rare presentation of progressive multifocal leukoencephalopathy in a patient with idiopathic CD4 lymphocytopenia (ICL). Background: Progressive multifocal leukoencephalopathy (PML) is a rare neurological disorder that is classically associated with immunosuppression. There are few reported cases of PML in non-immunocompromised individuals. We present a case of a patient with history of alcohol abuse, but no clear immunosuppresion risk, presenting with PML. Case Report A 55-year-old male was referred to our practice following two witnessed seizures with multiple subacute neurologic deficits. Relevant history included newly diagnosed atrial fibrillation and hyperlipidemia, in addition to chronic alcohol abuse. He endorsed headache, loss of peripheral vision and intermittent bilateral paresthesias of the extremities with associated gait imbalance. Brain MRI revealed T2 hyperintensities throughout the right hemisphere white matter and basal ganglia. Over the course of one month, he deteriorated clinically, with neurologic exam showing left hemiparesis, hemiparesthesia, homonomous hemianopia, and dysarthria. Repeat brain MRI showed worsening T2 hyperintense signal throughout the right hemisphere white matter, subcortical structures and the splenium. Lab testing included negative HIV antibody, CD4+ count of 293 cells/mm3, and mild leukocytotosis with increased absolute lymphocyte count. Hepatitis panel and HTLV-1/2 testing were negative. Brain biopsy confirmed diagnosis of PML. Within one month, he was wheelchair-dependent, with right sided deficits in addition to worsening of his previous left sided deficits. Conclusions: While CD4+ lymphocytopenia likely contributed to the development of PML in this case, there was no causal explanation for lymphocytopenia. To our knowledge, there have been 7 cases of PML in patients with hepatic cirrhosis and 10 cases of PML in patients with ICL. Therefore, although rare, neurologists should be aware of alternative causes of PML. Disclosure: Dr. Yaqub has nothing to disclose. Dr. Derani has nothing to disclose. Dr. Gheith has nothing to disclose. Dr. Aburashed has received personal compensation as a consultant.