Multiple sclerosis (MS) has been infrequently described in association with human immunodeficiency virus (HIV) infection. Underreporting, missed diagnoses or a true negative association between MS and HIV infection are all possible explanations for the paucity of published cases. Since MS involves inflammation and demyelination of the central nervous system by autoreactive T cells, immunosuppression caused by HIV infection would be expected to confer a reduced risk of MS. This report describes a case of relapsing-remitting MS in a woman with non-progressive HIV-1 infection for 5 years. The patient has stable normal CD4+ cell counts and a low viral load in the absence of combination antitretroviral treatment (cART). She experienced typical neurological symptoms of MS including optic neuritis, trigeminal neuralgia, and transverse myelitis. MRI of the spinal cord demonstrated multiple lesions on T2-weighted images. Immune mechanisms associated with HIV control that may have contributed to the development and relapses of MS in this patient are discussed. [ABSTRACT FROM AUTHOR]