Susac's Syndrome (SS) is an autoimmune endotheliopathy of cerebral, retinal and cochlear arterioles. We report of an HIV-infected woman who developed a first SS episode following a spontaneous reduction of plasma viral load and several relapses six years later, following initiation of combined antiretroviral therapy (cART). Corticosteroids and intravenous immunoglobulins alone did not control the disease, which improved after combined treatment with acyclovir and ganciclovir. SS onset in HIV infection and relapses during cART-induced immune reconstitution are consistent with the dysimmune nature of the disease. The response to anti-herpes drugs suggests a viral contribute in this case of SS.