Abstract
BACKGROUND: The comorbidity between Multiple Sclerosis (MS) and Human Immunodeficiency Virus (HIV) infection is particularly rare. Only a few cases of comorbidity of Clinically Definite(CD)-MS and HIV have been documented worldwide, while the potential beneficial role of antiretroviral therapy regarding MS activity has long been an area of debate. CASE REPORT: We present a 36-year old male, bearing a diagnosis of CD-MS for twelve years. He had been treated for ten years with interferon-beta-1b, when he voluntarily discontinued therapy, claiming clinical stability. One year later he was diagnosed positive for HIV and he started and continued only on efavirenz/emricitabine/tenofovir-disoproxil fumarate (ATRIPLA®), remaining relapse-free until today. CONCLUSION: This fact, in combination with the unique pharmaceutical composition of the drug, which contains a component similar to a newly-approved agent for MS, dimethyl fumarate, prompted us to review the literature regarding this rare comorbidity and to suggest that the role of the antiretroviral therapy should be further explored in MS.