Progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy is a demyelinating disease of the central nervous system caused by JC virus reactivation, usually when immune defenses are impaired.

JC virus: JC virus is a human polyomavirus that can persist silently and, after immune suppression, infect cells in the central nervous system. Its reactivation initiates the infection that causes this disease.
Cerebrospinal fluid: Cerebrospinal fluid is the clear fluid circulating around the brain and spinal cord. JC virus DNA can be detected in this fluid during diagnostic evaluation.
Astrocytoma: Astrocytoma is a tumor arising from astrocytes, a type of supporting cell in the central nervous system. The disease was first described in a patient with chronic lymphocytic leukemia and an astrocytoma.
Progressive rubella panencephalitis: Progressive rubella panencephalitis is a rare, late complication of congenital rubella involving progressive inflammation and degeneration of the brain. It is another rare progressive brain disease, but follows persistent rubella infection.
Oligodendrocyte: An oligodendrocyte is a central nervous system cell that produces and maintains myelin around axons. JC virus damages these myelin-producing cells.
Polymerase chain reaction: Polymerase chain reaction is a laboratory method that amplifies selected DNA sequences for detection and analysis. PCR testing of cerebrospinal fluid can identify JC virus DNA.
Chronic lymphocytic leukemia: Chronic lymphocytic leukemia is a cancer of mature B lymphocytes that accumulate in blood, bone marrow, and lymphoid tissues. Its association with the first recognized case highlighted vulnerability during immune dysfunction.
HIV-associated neurocognitive disorder: HIV-associated neurocognitive disorder is a spectrum of cognitive and motor impairment linked to HIV infection. It can cause neurological decline in immunocompromised people without the focal demyelination of this disease.
Demyelination: Demyelination is the loss or destruction of insulating myelin around nerve fibers. It is the tissue injury underlying the disease’s neurological deficits.
Brain biopsy: A brain biopsy is the removal of a small brain tissue sample for microscopic and laboratory examination. It can establish the diagnosis when fluid testing and imaging remain inconclusive.

Linked from 5 pages