Idiopathic hypertrophic cranial pachymeningitis of the cavernous sinus mimicking lymphocytic hypophysitis.

A 56-year-old female presented with idiopathic hypertrophic cranial pachymeningitis manifesting as headache, hypopituitarism, and diabetes insipidus, mimicking lymphocytic hypophysitis. Five months later, she complained of double vision and unusual right facial sensation. The diagnosis was based on magnetic resonance imaging, angiography, and meningeal biopsy via transsphenoidal surgery, and exclusion of other know causes of pachymeningitis. Despite initial response to steroid treatment, her symptoms recurred repeatedly and she became steroid-dependent. Repetition of short-term steroid pulse therapy restrained the deterioration of her condition. The clinical presentation of idiopathic hypertrophic cranial pachymeningitis is variable, and it may develop with signs of adjacent tissue involvement. Resultant secondary hypophysitis must be differentiated from lymphocytic hypophysitis. Initial steroid therapy is effective in improving symptoms, but should be carefully considered since the natural course of this disease seems to be self-limited.