Incidence and risk factors for the immune reconstitution inflammatory syndrome in HIV patients in South Africa: a prospective study.
OBJECTIVE
To determine the incidence, clinical manifestations, risk factors and outcome of immune reconstitution inflammatory syndrome (IRIS) in South Africa.


METHODS
Prospective surveillance cohort and nested case-control study in a large, University hospital-based antiretroviral therapy (ART) clinic.


METHODS
A total of 423 ART-naive HIV-infected South African patients were followed for signs and symptoms IRIS during the first 6 months of ART. We also performed a nested case-control study with controls matched to IRIS cases on ART duration.


RESULTS
During the first 6 months of ART, 44 (10.4%) patients experienced IRIS for an overall incidence rate of 25.1 cases per 100 patient-years. Diagnoses included tuberculosis (18/44, 41%), abscess formation and suppurative folliculitis (8/44, 18.2%), varicella zoster (6/44, 13.6%), herpes simplex (4/44, 9.1%), cryptococcal meningitis (3/44, 6.8%), molluscum contagiosum (3/44, 6.8%), and Kaposi's sarcoma (2/44, 4.5%). Median IRIS onset was 48 days (interquartile range, 29-99) from ART initiation. In comparison with controls, IRIS cases had significantly lower CD4 cell counts at baseline (79 versus 142 cells/microl; P = 0.02) and at IRIS diagnosis (183 versus 263 cells/microl; P = 0.05), but similar virological and immunological response to ART. In multivariable analyses, higher baseline CD4 cell count was protective of developing IRIS (HR 0.72 per 50 cells/microl increase). Most IRIS cases were mild, with ART discontinued in three (6.8%) patients, corticosteroids administered to four (9.1%) patients, and hospitalization required in 12 (27.3%) patients. Two deaths were attributable to IRIS.


CONCLUSIONS
IRIS may affect 10% of patients initiating ART in Africa, particularly those with advanced immunosuppression, but severe, life-threatening IRIS is uncommon.
Murdoch
David M
DM
Division of Pulmonary and Critical Care Medicine, Duke University Medical Center, Durham, North Carolina NC 27710, USA. dmurdoch@email.unc.edu
Venter
Willem D F
WD
Feldman
Charles
C
Van Rie
Annelies
A
D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology* / Q000401:mortality; D006801:Humans; D054019:Immune Reconstitution Inflammatory Syndrome / Q000150:complications / Q000453:epidemiology* / Q000276:immunology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D013019:South Africa; D016019:Survival Analysis; D013997:Time Factors
D044966:Anti-Retroviral Agents