Granulomatous angiitis of the central nervous system complicated by the syndrome of inappropriate antidiuretic hormone

Abstract We report an autopsy case of granulomatous angiitis of the central nervous system (GANS) complicated by the syndrome of inappropriate antidiuretic hormone (SIADH). A 88-year old female was admitted because of progressive mental deterioration, fever, and vomiting. A computed tomogram disclosed bilateral periventricular lucency, and a low-density area in the right occipital lobe. Laboratory studies during her hospital stay, revealed hyponatremia, hypoalbuminemia, and increased antidiuretic hormone. Treatment with antibiotics, hypertonic saline solution, and steroids, and water restriction was ineffective, and the patient died six weeks after admission. Autopsy examination of the brain revealed slightly turbid meninges with multiple small infarctions in the corona raiata of both cerebral hemispheres. Microscopic study disclosed granulomatous inflammation with many giant cells in the walls of small and medium sized vessels, and the adventitia and media were more involved than the intima. Their lumens were narrowed, and many thrombi were observed. Extensive non-granulomatous inflammatory change was found mainly in the subarachnoid space. All of these findings were similar to the GANS firstly reported by Cravioto et al, in 1959. Since the blood vessels in the central nervous system play an important part in any inflammatory conditions and the blood vessels may be involved by bacterial, fungal, parasitic or viral meningitis, various microorganisms have been suspected as the cause of GANS, including mycoplasma, herpes zoster, herpes simplex viruses, cytomegalovirus, and human T-lymphotropic virus type III (HTLV-III). Some reported cases have been associated with Hodgkin's disease and cerebral amyloid angiopathy. We could not identify any cause in our case.(ABSTRACT TRUNCATED AT 250 WORDS)