BACKGROUND: World Health Organization (WHO) guidelines for the use of antiretroviral therapy (ART) in resource-limited settings state that CD4 cell counts may be used to indicate when ART regimens should be changed because of treatment failure. The performance of immunologic monitoring for this purpose has not been evaluated, however. METHODS: Participants aged > or =18 years from the British Columbia HIV/AIDS Drug Treatment Program who had CD4 cell counts < or =200 cells/microL or an AIDS diagnosis at baseline had CD4 cell counts measured at 6 and 12 months after treatment initiation. Logistic regression analysis was used to calculate sensitivity, specificity, and positive and negative predictive values for immunologic responses in terms of predicting failure to achieve 2 viral load measurements < 500 copies/mL within 1 year. RESULTS: Viral load suppression occurred in 674 (60%) of 1125 subjects. Using no increase in CD4 cell counts at 6 months as a definition of treatment failure had a sensitivity of 34%, specificity of 94%, positive predictive value of 75%, and negative predictive value of 71% for predicting failure to achieve virologic suppression. Using 12-month CD4 cell count values, the measurements were 35%, 95%, 79%, and 73%, respectively. CONCLUSION: Immunologic criteria to predict which patients have not achieved virologic suppression results in significant misclassification of therapeutic responses.
BACKGROUND: World Health Organization (WHO) guidelines for the use of antiretroviral therapy (ART) in resource-limited settings state that CD4 cell counts may be used to indicate when ART regimens should be changed because of treatment failure. The performance of immunologic monitoring for this purpose has not been evaluated, however. METHODS:Participants aged > or =18 years from the British Columbia HIV/AIDS Drug Treatment Program who had CD4 cell counts < or =200 cells/microL or an AIDS diagnosis at baseline had CD4 cell counts measured at 6 and 12 months after treatment initiation. Logistic regression analysis was used to calculate sensitivity, specificity, and positive and negative predictive values for immunologic responses in terms of predicting failure to achieve 2 viral load measurements < 500 copies/mL within 1 year. RESULTS: Viral load suppression occurred in 674 (60%) of 1125 subjects. Using no increase in CD4 cell counts at 6 months as a definition of treatment failure had a sensitivity of 34%, specificity of 94%, positive predictive value of 75%, and negative predictive value of 71% for predicting failure to achieve virologic suppression. Using 12-month CD4 cell count values, the measurements were 35%, 95%, 79%, and 73%, respectively. CONCLUSION: Immunologic criteria to predict which patients have not achieved virologic suppression results in significant misclassification of therapeutic responses.
Authors: I Ssebugenyi; A Kizza; B Mpoza; G Aluma; I Boaz; K Newell; O Laeyendecker; J P Shott; D Serwadda; S J Reynolds Journal: Int J STD AIDS Date: 2011-07 Impact factor: 1.359
Authors: Olivia Keiser; Hannock Tweya; Paula Braitstein; François Dabis; Patrick MacPhail; Andrew Boulle; Denis Nash; Robin Wood; Ruedi Lüthi; Martin W G Brinkhof; Mauro Schechter; Matthias Egger Journal: Trop Med Int Health Date: 2009-12-09 Impact factor: 2.622
Authors: Steven J Reynolds; Cissy Kityo; Claire W Hallahan; Geoffrey Kabuye; Diana Atwiine; Frank Mbamanya; Francis Ssali; Robin Dewar; Marybeth Daucher; Richard T Davey; Peter Mugyenyi; Anthony S Fauci; Thomas C Quinn; Mark R Dybul Journal: PLoS One Date: 2010-04-22 Impact factor: 3.240
Authors: Mattia C F Prosperi; Michal Rosen-Zvi; André Altmann; Maurizio Zazzi; Simona Di Giambenedetto; Rolf Kaiser; Eugen Schülter; Daniel Struck; Peter Sloot; David A van de Vijver; Anne-Mieke Vandamme; Anders Sönnerborg Journal: PLoS One Date: 2010-10-29 Impact factor: 3.240
Authors: Olivia Keiser; Patrick MacPhail; Andrew Boulle; Robin Wood; Mauro Schechter; François Dabis; Eduardo Sprinz; Matthias Egger Journal: Trop Med Int Health Date: 2009-07-14 Impact factor: 2.622