PLEX
Also written as: PLEX — plasma exchange
Plasma exchange therapy used to remove pathogenic antibodies in severe neuroinflammatory conditions.
Full Definition
Plasma exchange (PLEX), also known as plasmapheresis, is a therapeutic procedure that involves the mechanical removal and replacement of patient plasma to eliminate circulating pathogenic factors such as autoantibodies, immune complexes, and inflammatory mediators. In neuroimmunology, PLEX is employed as an acute treatment for severe antibody-mediated CNS diseases including neuromyelitis optica spectrum disorder, anti-NMDA receptor encephalitis, myasthenia gravis, and acute inflammatory demyelinating polyneuropathy (Guillain-Barré syndrome). The procedure typically involves 5-7 exchanges performed on alternate days, with each exchange removing 1-1.5 plasma volumes. Replacement fluid is usually albumin or fresh frozen plasma. PLEX can provide rapid clinical improvement by reducing antibody titers, though the effect may be temporary without concurrent immunosuppressive therapy. Potential complications include hypotension, bleeding, infection, and electrolyte disturbances.
Usage
Usage note: Specify number of exchanges planned and replacement fluid type in treatment orders.
In Context
- "The patient underwent five sessions of PLEX for severe anti-NMDA receptor encephalitis with marked clinical improvement." — Treatment summary
- "PLEX was initiated emergently for rapidly progressive neuromyelitis optica spectrum disorder." — Acute care note