CASE PRESENTATION: He was first seen at an outlying hospital for AMS, which was attributed to drug use. Chest x-ray (CXR) revealed bilateral cavitary lung lesions, and he was treated for pneumonia and discharged. He returned one month later with persistent AMS. Brain MRI showed diffuse leptomeningeal enhancement. Lumbar puncture (LP) revealed lymphocytic pleocytosis, low glucose, and elevated protein. All infectious testing was negative. Transbronchial lung biopsy showed inflammation, but no organisms. He was discharged on itraconazole for presumed disseminated fungal infection. He returned with progressive mental status changes four months later. MRI and LP were unchanged, but CSF angiotensin-converting enzyme (ACE) was four times normal. Chest imaging again showed cavitary lesions, and CT guided lung biopsy revealed necrotizing granulomatous inflammation. Microbiological tests were again negative except one serum complement fixation (CF), which was positive for histoplasmosis. The patient was treated with amphotericin and discharged on itraconazole until he presented to us two months later. By this time, the patient had developed gait abnormalities and urinary incontinence. Imaging demonstrated progression of prior lesions. Both transbronchial lung and brain biopsies revealed necrotizing and non-necrotizing granulomas. All fungal tests including histoplasmosis fungal CF were negative. Serum ACE level was elevated and, considering prior elevated CSF ACE and granulomas in the lung and brain, sarcoidosis was diagnosed. The patient was treated with high dose steroids and his clinical status, along with lung and brain lesions, improved.