Postvaricella myelitis

This code describes inflammation of the spinal cord (myelitis) that occurs as a neurological complication following a varicella (chickenpox) infection. It represents a rare, but serious, post-infectious demyelinating syndrome affecting the central nervous system.

Use this code when documentation clearly indicates myelitis developing after a confirmed or presumed varicella infection. This typically presents with acute or subacute onset of motor weakness, sensory disturbances, or bladder/bowel dysfunction, with a recent history of chickenpox. Supporting documentation includes physician notes detailing the neurological symptoms and their temporal relationship to varicella.

• Ensure the documentation explicitly links the myelitis to a preceding varicella infection.
• Do not confuse with myelitis due to other viral etiologies; verify the varicella connection.
• Sequence this code as the primary diagnosis when it is the reason for the encounter.