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Hemeroteca 
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Advanced HIV, Other Factors Increase Risk of Unusual TB Presentation May 29, 2010 NEW YORK (Reuters Health) May 17 - Advanced HIV infection, African origins, and a strong response to combined antiretroviral therapy (cART) increase the risk of an atypical inflammatory presentation of incident tuberculosis, researchers from France report in the April 27th AIDS. This presentation is known as "unmasking tuberculosis-associated immune reconstitution inflammatory syndrome" (TB-IRIS). It's distinct from "paradoxical TB-IRIS," which involves deterioration of pre-existing TB. Instead, unmasking TB-IRIS in patients with cART is characterized by active tuberculosis with heightened intensity of clinical manifestations that develops within 3 months after therapy begins. To learn more about the features and risk factors of unmasking TB-IRIS, Dr. Nadia Valin from Hospital Saint-Antoine, Paris, France, and colleagues studied 47 HIV-infected patients diagnosed with tuberculosis following cART initiation. Eleven patients (23%) developed an unmasking TB-IRIS. Unmasking IRIS was self-limiting in 6 cases. Two patients needed steroids for respiratory distress and cerebral involvement. Five patients with disseminated tuberculosis had cART withdrawn. Two patients had central nervous system (CNS) involvement, including one who died. For a case-control analysis, the researchers matched 3 HIV patients initiating cART with each case of unmasking IRIS. Patients with unmasking IRIS were more often of African origin (65% vs 18%) and had a higher median HIV-RNA load at cART initiation (5.2 vs 4.7 log). They also had more robust responses after a month on cART, as reflected by stronger CD4 T-cell percentage increases (+7 vs +2) and higher likelihood of more than a 3-log decrease in plasma HIV-RNA load (73% vs 27%). "Predictors of severe and life-threatening presentations of unmasking TB-IRIS in patients initiating cART are still unknown, and further studies should assess this crucial issue," the authors say. While the optimal treatment is also unknown, they advise that "as some cases of unmasking TB-IRIS are life-threatening, it might be appropriate to consider discontinuation of cART, at least in case of CNS involvement or of acute respiratory distress syndrome pending improvement of clinical status with specific antibiotic treatment." The authors list 3 implications of their findings. First, starting cART at higher CD4 T-cell levels might lower the risk of unmasking TB-IRIS. Second, it's important to screen for active tuberculosis before cART begins. And finally, patients with a low CD4 T-cell count and a high plasma HIV-RNA viral load at baseline should be monitored carefully during the first 3 months of cART, especially if they're having a strong virological or immune response. Article abstract about this note: http://journals.lww.com/aidsonline/Abstract/publishahead/Risk_factors_for__unmasking_immune_reconstitution.99533.aspx (AIDS 2010). Fuente: Medscape Today 
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