Relapsing demyelinating disease after chicken pox in a child

Post-infectious encephalomyelitis (PIE), an inflammatory demyelinating disorder, usually begins days to weeks after virus (usually measles, Epstein–Barr virus [EBV], cytomegalovirus [CMV], or varicella zoster virus [VZV]) or mycoplasma infection, and after vaccination with hepatitis B virus,1 Bordetella pertussis , and possibly influenza virus.2 The mechanism by which the infectious agent triggers demyelination is uncertain. Two days after varicella infection, a 3-year-old girl developed fever, confusion, lethargy, and status epilepticus. CSF was acellular with normal protein and glucose, without oligoclonal bands (OGBs) or amplifiable VZV DNA, and no VZV IgM or IgG antibody in serum or CSF. Brain CT revealed diffuse white matter edema. After IV treatment with ceftriaxone, acyclovir, clonazepam, and phenobarbital, seizures stopped and mental status was normal. Neurologic signs included increased DTRs, greater on the left, and ankle clonus bilaterally. Twenty days later, she became febrile. Neurologic signs consisted of ataxia with dysmetria bilaterally and intention tremor in the arms. Serum contained VZV IgM antibody, and VZV IgG was 6,800 international units (IU) per liter (normal < 50 IU/L). There was no amplifiable VZV DNA in blood. CSF was acellular, protein 31 mg%; …