[Intracranial hypertrophic pachymeningitis with high perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) occurred in a patient on hemodialysis].

We present a 66-year-old woman undergoing hemodialysis who developed intracranial hypertrophic pachymeningitis. Neurological examinations revealed a loss of bilateral visual acuity with optic atrophy, headache, and markedly restricted bilateral extraocular movement. MRI examinations demonstrated homogenous hypertrophic dural enhancement compatible with hypertrophic cranial pachymeningitis, and biopsied dural specimen revealed chronic inflammatory changes with proliferation of dense collagen fibers. There was no direct evidence of vasculitis and specific infections including tuberculosis and troponema pallidum. Most of the inflammatory infiltrates were demonstrated to be T lymphocytes. Intriguingly, p-ANCA was found to be highly elevated at x 220 and decreased to x 110 after steroid treatment. Neurological manifestations and radiological findings also improved in accordance with the lowering of p-ANCA. Although a few reports have described similar conditions such as chronic renal failure accompanying hemodialysis and pachymeningitis, and though vasculitis was not depicted histologically in this patient, we considered that immunological mechanisms probably provoked the patient's glomerulonephritis and pachymeningitis. Additionally, positive reaction against hepatitis c virus might have influenced the immunological system leading to the occurrence of the pachymeningitis.