Hypertrophic pachymeningitis : varied manifestations of a single disease entity.

Hypertrophic pachymeningitis is a unique clinical entity characterised by fibrosis and thickening of the duramater with resulting neurological dysfunction. Three cases of this entity are described. Presenting features were headaches and cranial neuropathies in two patients and predominantly cerebellar dysfunction in the third. One of the patients also had evidence of spinal involvement. Lower cranial nerves were chiefly involved in two patients whereas optic nerve was the predominantly affected nerve in one. Except for the presence of rheumatoid arthritis in one of the patients, we could not document clinical or biochemical evidence of any predisposing infective, inflammatory or infiltrative condition in the other two. All three patients had characteristic changes on imaging suggestive of thickened and enhancing duramater. Although variable steroid responsiveness was seen in all the three patients, tendency towards steroid dependence was evident. The clinical presentations, causes, radiological features, management options and differential diagnosis of this unique clinical syndrome have been discussed.