Idiopathic hypertrophic pachymeningitis in a child with hydrocephalus.

Idiopathic hypertrophic pachymeningitis is a rare but increasingly recognized disorder characterized by diffuse thickening of the dura mater of unknown etiology. The inflammation usually involves the cranial or spinal dura mater, with resultant neurologic deficits. Although it is reported primarily in adults, there is one previous report describing the condition in a child. Described here is the case of a child who presented at the age of 3.5 years with idiopathic hypertrophic pachymeningitis involving the entire central nervous system, with poor response to steroids, cyclophosphamide, and intraventricular cytarabine.