Individualized immunotherapy for immune reconstitution-associated cortical encephalitis in an HIV-positive cryptococcal meningitis patient: a case report

Background Neurological immune reconstitution inflammatory syndrome (IRIS) in HIV can present variably. We report a case of steroid-dependent, recurrent cortical encephalitis with a distinctive migratory Magnetic Resonance Imaging (MRI) pattern following cryptococcal meningitis. Case presentation A 38-year-old male with advanced HIV (CD4 11/μL) developed cryptococcal meningitis. After antifungal induction and switching to effective antiretroviral therapy (bictegravir/emtricitabine/tenofovir alafenamide), he suffered recurrent neurological episodes. Serial brain MRIs showed sequentially appearing and resolving T2/Fluid-Attenuated Inversion Recovery (FLAIR) hyperintensities in the bilateral frontal lobes, left cingulate gyrus, and left occipital cortex, despite negative infectious and autoimmune workup. Symptoms were steroid-responsive but relapsed upon tapering. Lasting remission was achieved only after adding mycophenolate mofetil (MMF), allowing corticosteroid withdrawal. Conclusions This case describes a “migratory cortical encephalitis” phenotype of Central Nervous System (CNS)-IRIS. It highlights that cortical grey matter can be the primary target in severe IRIS and illustrates the utility of steroid-sparing agents like MMF for managing refractory, steroid-dependent neuroinflammation in this context.