Progressive Multifocal Leukoencephalopathy in a Patient with Multifocal Neurological Manifestations Caused by Solitary Brainstem Involvement

A Japanese man in his 60s on medication for chronic lymphocytic leukemia presented with progressive, multifocal neurological manifestations. Magnetic resonance imaging showed a small, solitary region of brain -stem involvement. Sensitive real-time polymerase chain reaction testing detected a small amount of JC virus (JCV) DNA (170 copies/mL) with pathogenic mutation in cerebrospinal fluid. We diagnosed the patient with progressive multifocal leukoencephalopathy (PML). The small PML lesion may have caused multifocal neu-rological symptoms because of its focal brainstem involvement. This case contributes to knowledge regarding the diagnosis and treatment of brainstem PML in the context of hematologic malignancies and other underly-ing diseases.

Automated summary

A Japanese man in his 60s with chronic lymphocytic leukemia developed progressive multifocal neurological symptoms. The MRI showed a small solitary brainstem lesion. PCR testing detected a small amount of JC virus DNA in his cerebrospinal fluid, confirming a diagnosis of progressive multifocal leukoencephalopathy (PML). This case contributes to knowledge about brainstem PML in patients with hematologic malignancies and other underlying diseases.