<prompt> All are true about Immune Reconstitution Inflammatory syndrome IRIS except:It occurs when CD4 cell count is 50 cellsmm3Develops after initiation of anti-retroviral therapyAssociated with delayed type of hypersensitivityDoes not require a specific antimicrobial therapy for recovery  <response>: Immune Reconstitution Inflammatory syndrome IRIS In patients with CD4 count 100 cellsmm3. In HIV infection, an exaggerated inflammatory reaction to a disease-causing microorganism that sometimes occurs when the immune system begins to recover following treatment with antiretroviral ARV drugs. 2 IRIS scenarios : Unmasking- Flare-up of an underlying occult oppounistic infection. Paradoxical- Symptomatic relapse of a prior infection despite microbiologic treatment success. MECHANISM : Increased inflammation as the recovering immune system recognizes the antigens , there is hypothesized reconstitution of antigen-specific T cell-mediated immunity with activation of the immune system following HIV therapy against persisting antigen, whether present as intact organisms, dead organisms, or debris.as bodys immune response recovers following HAA There is a cytokine storm with a predominant type-1 helper T-cell interferon-gamma response. Delayed hypersensitivity Cryptococcus neoformans is the usual pathogen eliciting more severe disease Rx- Systemic coicosteroids during IRIS may be beneficial in preventing death or progressive neurological deterioration. 