ADA and diabetes mellitus: CSF: cerebrospinal fluid; CNS: central nervous system; HIV: human immunodeficiency virus; CD4: CD4 lymphocytes; M: male; F: female; L: leucocytes; M: monocytes; Lymph: lymphocytes; P: proteins, G: glucose; ADA: adenosine deaminase; DM: diabetes mellitus; IgG: immunoglobulin G; IgA: immunoglobulin A