1186 patients underwent CSF ACE testing; elevated in 66 (median level: 4.4 U/L, range 2.6-40.0 U/L). Mean age 55.7 ±14.2, 40 females, 26 males. Diagnoses included: meningitis (n=13; 6 aseptic, 2 bacterial, 3 fungal, 1 viral, 1 parasitic), miscellaneous neurologic presentations (n=10; 3 headache, 3 encephalopathy, 2 seizure, 1 spinocerebellar ataxia, 1 acute stroke), neurosarcoidosis (n=9; 8 probable, 1 possible), CNS malignancy (n=10; 5 primary, 5 secondary), structural (n=7; 3 CSF leak, 2 hydrocephalus, 2 compressive myelopathy), autoimmune/inflammatory (n=7; 5 CNS demyelination, 2 Guillain Barre Syndrome), unclassified (n=7; 5 incomplete workup, 2 lost to follow-up), neuromuscular (n=5; 4 peripheral neuropathy, 1 myopathy), idiopathic meningeal enhancement (n=4). Neuroleptic use found in 2 secondary CNS malignancy, 2 encephalopathy, 1 aseptic meningitis, 1 headache (n=6). 24/66 (36.4%) demonstrated meningeal enhancement on MRI (10 leptomeningeal, 10 pachymeningeal, 4 both).  

Elevated CSF ACE was seen in association with a variety of neurologic diagnoses demonstrating elevated CSF ACE is not specific for sarcoidosis and actually may be more associated with meningitis (19.7%) than sarcoidosis (13.6%). Across diagnoses, meningeal enhancement was a relatively common finding, 36.4% of cases, indicating CSF ACE may be a more common marker of meningeal pathology than of sarcoidosis.