Idiopathic hypertrophic pachymeningitis resulting in delayed panhypopituitarism

To describe an adult man with idiopathic hypertrophic pachymeningitis (IHPM) that progressed to involve the pituitary gland and caused hypopituitarism 6 years after the onset of the first symptom.

We describe the slow 6-year progression of IHPM in a man being treated with steroids, radiation, and antineoplastic medications and present clinical, pathologic, and imaging data. The pertinent literature is also reviewed.

A 35-year-old man who presented with headaches, pain, and sensory loss on the right side of his face had thickened, inflamed dura without granulomas. Initially, the right middle fossa, the lateral wall of the right cavernous sinus, and the tentorium were involved. Results from a dural biopsy specimen were consistent with IHPM. His symptoms were only partially controlled with continuous high-dose steroids, cyclophosphamide, azathioprine, and radiation therapy. IHPM was diagnosed based on findings from an open brain biopsy. Other pathologic causes of inflammatory dural thickening were excluded. Six years after the onset of the first clinical manifestation of IHPM, the patient developed panhypopituitarism. Magnetic resonance imaging showed that the inflammatory process had invaded the pituitary gland. IHPM was confirmed by findings from transsphenoidal biopsy.

IHPM is a rare disorder characterized by an unexplained inflammatory thickening of the dura at the skull base. The usual clinical symptoms are intractable headache and cranial nerve palsies. Physicians must be aware that IHPM can be slowly progressive despite attempted treatment, and that the disease process can invade the sella with dysfunction of both the anterior and the posterior pituitary gland.