Progressive multifocal leukoencephalopathy--incidental finding in the forensic neuropathological examination

Area of Science:

• Neurology
• Virology
• Pathology

Background:

• Progressive Multifocal Leukoencephalopathy (PML) is a rare, fatal demyelinating disease of the central nervous system (CNS).
• PML is typically caused by the JC virus (JCV), a polyomavirus, which reactivates in severely immunocompromised individuals.
• While JCV infection is common, PML is extremely rare in immunocompetent individuals.

Observation:

• A case report of an elderly, immunocompetent male with no prior medical history is presented.
• The patient died of sepsis 50 days after sustaining severe flame burns.
• PML was discovered incidentally during forensic autopsy neuropathological examination, having been missed during hospitalization.

Findings:

• JC virus (JCV) was detected in the brain tissue via in situ hybridization, confirming PML.
• The autopsy revealed extensive and severe demyelinating lesions characteristic of PML.
• The rapid progression and severity of PML in this immunocompetent host were notable.

Implications:

• This case highlights that immunocompetence does not exclude PML diagnosis.
• It suggests severe physiological stress, like extensive burns, may contribute to JCV reactivation even in immunocompetent hosts.
• Revising diagnostic criteria for PML to include immunocompetent patients under specific circumstances is warranted.