A case of idiopathic hypertrophic pachymeningitis presenting with chronic headache and multiple cranial nerve palsies

RATIONALE Idiopathic hypertrophic pachymeningitis (IHP) is a rare condition, characterized by a chronic fibrosing inflammatory process usually involving either the intracranial or spinal dura mater, but rarely both. Here, we report a rare case of IHP affecting both the intracranial and spinal dura mater. We also discussed the diagnosis, management, and outcome of IHP. PATIENT CONCERNS We reviewed the case of a 60-year-old woman presenting with chronic headache, multiple cranial nerve palsies and gait disturbance. Magnetic resonance imaging (MRI) of her head revealed thickened and contrast-enhanced dura in the craniocervical region as well as obstructive hydrocephalus and cerebellar tonsillar herniation. The patient had a suboccipital craniectomy and posterior decompression through C1 plus a total laminectomy. The dura was partially resected to the extent of the bony decompression, and a duroplasty was performed. DIAGNOSES Microscopic examination of the surgically resected sample showed chronic inflammatory changes, lymphoplasmacytic cell infiltration, fibrous tissue hyperplasia, and hyaline degeneration. Blood tests to evaluate the secondary causes of hypertrophic pachymeningitis (HP) were unremarkable. INTERVENTIONS Steroid was used to treat suspected IHP. OUTCOMES Postoperatively, the patient showed gradual improvement in her headache, glossolalia, and bucking. Prior to discharge, a follow-up MRI showed improvement of the dura mater thickening. LESSONS IHP is a chronic inflammatory disorder of the dura mater that usually causes neurological deficits. Clinical manifestations of IHP, MRI findings, and laboratory abnormalities are the essential components for making an accurate diagnosis. When the radiological or laboratory evaluation is uncertain, but neurological deficits are present, a prompt surgical approach should be considered. Postoperative steroid therapy and close observation for recurrence are necessary to ensure a good long-term outcome.