Cerebrospinal fluid beta-2-microglobulin in multiple sclerosis and AIDS dementia complex.

Cerebrospinal fluid (CSF) and serum concentrations of beta-2-microglobulin (beta-2-m) were evaluated in 19 patients with clinically definite multiple sclerosis (MS), in 21 with AIDS dementia complex (ADC), and in 20 subjects with other neurological diseases (OND). CSF beta-2-m and CSF/serum beta-2-m ratio were significantly higher in the patients with ADC than in the MS and OND patients. The CSF and serum levels of beta-2-m in MS patients were not significantly different from those of OND patients. These findings indicate that CSF beta-2-m and CSF/serum ratio may be a useful marker in the diagnosis of ADC. In MS patients the beta-2-m CSF determinations are of no value.