[A case of progressive multifocal leukoencephalopathy associated with daratumumab, bortezomib, and dexamethasone for...

Area of Science:

• Neurology
• Oncology
• Infectious Diseases

Background:

• Multiple myeloma (MM) is a hematologic malignancy.
• Daratumumab, bortezomib, and dexamethasone (DBd) is a common treatment regimen for MM.
• Immunosuppression is a known risk factor for opportunistic infections.

Observation:

• An 83-year-old male with MM presented with visual disturbance and hemiparalysis one month post-DBd therapy.
• Laboratory tests revealed a CD4+ T-lymphocyte count of 132/μl.
• Cerebrospinal fluid (CSF) analysis detected JC virus (JCV) DNA via PCR.

Findings:

• Magnetic resonance imaging (MRI) showed characteristic high-intensity signals in the occipital lobes and left precentral gyrus.
• The patient was diagnosed with progressive multifocal leukoencephalopathy (PML).
• Despite treatment with mefloquine and mirtazapine, CSF JCV-DNA PCR levels did not decrease, and the patient died six months after symptom onset.

Implications:

• This case highlights the potential for PML in MM patients receiving DBd therapy, particularly those with iatrogenic immunosuppression (low CD4+ counts).
• Clinicians should consider PML in the differential diagnosis of neurological symptoms in MM patients undergoing immunosuppressive therapy.
• Further research is needed to explore preventative strategies and optimize treatment for PML in this vulnerable patient population.