Multifocal multinucleated giant cell myelitis in an AIDS patient

Area of Science:

• Neurology
• Immunology
• Pathology

Background:

• A 19-year-old human immunodeficiency virus (HIV)-positive male with a history of cerebral toxoplasmosis presented with progressive lower limb weakness and urinary retention.
• Intravenous drug use was a significant risk factor in this patient's medical history.

Observation:

• Neurological examination revealed flaccid paraparesis and abnormal reflexes, with normal sensory examination and myelography.
• Cerebrospinal fluid analysis showed elevated protein levels and mild pleocytosis.
• The patient's condition deteriorated, leading to death from septic peritonitis one month after admission.

Findings:

• Neuropathological examination identified chronic toxoplasmosis lesions in the brain and disseminated small necrotic foci with myelin loss, microglial proliferation, macrophages, and multinucleated giant cells (MGC) throughout the spinal cord.
• Immunohistochemistry confirmed the presence of HIV antigens (p24 and p17) within macrophages, MGC, and microglial cells in the spinal cord lesions.
• These spinal cord lesions were consistent with multifocal giant cell encephalitis, despite the brain being spared.

Implications:

• This case demonstrates that HIV-related multifocal inflammatory changes can be predominantly or exclusively localized to the spinal cord.
• Such spinal cord-restricted inflammation can manifest as a significant myelopathy in patients with acquired immunodeficiency syndrome (AIDS).
• The findings underscore the importance of considering HIV-associated myelopathy in the differential diagnosis of neurological deficits in AIDS patients, even when brain imaging is normal.