Accuracy of immunological criteria for identifying virological failure in children on antiretroviral therapy - The IeDEA Southern Africa Collaboration

School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa.
Tropical Medicine & International Health (Impact Factor: 2.3). 08/2011; 16(11):1367-71. DOI: 10.1111/j.1365-3156.2011.02854.x
Source: PubMed

ABSTRACT To determine the diagnostic accuracy of World Health Organization (WHO) 2010 and 2006 as well as United States Department of Health and Human Services (DHHS) 2008 definitions of immunological failure for identifying virological failure (VF) in children on antiretroviral therapy (ART).
Analysis of data from children (<16 years at ART initiation) at South African ART sites at which CD4 count/per cent and HIV-RNA monitoring are performed 6-monthly. Incomplete virological suppression (IVS) was defined as failure to achieve ≥1 HIV-RNA ≤400 copies/ml between 6 and 15 months on ART and viral rebound (VR) as confirmed HIV-RNA ≥5000 copies/ml in a child on ART for ≥18 months who had achieved suppression during the first year on treatment.
Among 3115 children [median (interquartile range) age 48 (20-84) months at ART initiation] on treatment for ≥1 year, sensitivity of immunological criteria for IVS was 10%, 6% and 26% for WHO 2006, WHO 2010 and DHHS 2008 criteria, respectively. The corresponding positive predictive values (PPV) were 31%, 20% and 20%. Diagnostic accuracy for VR was determined in 2513 children with ≥18 months of follow-up and virological suppression during the first year on ART with sensitivity of 5% (WHO 2006/2010) and 27% (DHHS 2008). PPV results were 42% (WHO 2010), 43% (WHO 2006) and 20% (DHHS 2008).
Current immunological criteria are unable to correctly identify children failing ART virologically. Improved access to viral load testing is needed to reliably identify VF in children.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background. The performance of clinical and immunological criteria to predict virological failure in HIV-infected children receiving antiretroviral therapy (ART) is not well documented.Objective. To determine the validity of clinical and immunological monitoring in detecting virological failure in children on ART.Methods. A total of 218 children were included in the study. All were from care and treatment clinics in Dar es Salaam, Tanzania. Their mean age was 10.6 years, 122 (56.0%) were males, and the mean time on ART was 40.9 months. The study was conducted from August 2011 to March 2012. Data on sociodemographic and clinical characteristics and immunological and virological failure were based on World Health Organization definitions. Blood samples were collected for CD4+ T-cell count and viral load tests.Results. Of 217 children with available viral load results, 124 (57.1%) had virological failure (>400 copies/mL), 25.0% immunological failure and 11.5% clinical failure. The sensitivity, specificity, positive predictive value and negative predictive value of clinical criteria were 12.9%, 90.3%, 64.0% and 43.8%, respectively, those for immunological criteria 22.6%, 73.1%, 53.3% and 41.4%, and those for the combination of clinical and immunological monitoring 25.8%, 69.9%, 53.3% and 41.4%. Children who received nevirapine (NVP)-based regimens were two times more likely (odds ratio 2.0; 95% confidence interval 1.20 - 3.64) to have virological failure than those on efavirenz and protease inhibitor-based regimens. Conclusions. The study demonstrated poor performance of currently recommended clinical and immunological criteria for monitoring HIV-infected children on ART. Moreover, children on NVP-based regimens had a higher risk of developing virological failure than those on other regimens.
    10/2014; 104(10):696-9. DOI:10.7196/samj.7807
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Many paediatric antiretroviral therapy (ART) programmes in Southern Africa rely on CD4(+) to monitor ART. We assessed the benefit of replacing CD4(+) by viral load monitoring. Design: A mathematical modelling study. Methods: A simulation model of HIV progression over 5 years in children on ART, parameterized by data from seven South African cohorts. We simulated treatment programmes with 6-monthly CD4(+) or 6- or 12-monthly viral load monitoring. We compared mortality, second-line ART use, immunological failure and time spent on failing ART. In further analyses, we varied the rate of virological failure, and assumed that the rate is higher with CD4(+) than with viral load monitoring. Results: About 7% of children were predicted to die within 5 years, independent of the monitoring strategy. Compared with CD4(+) monitoring, 12-monthly viral load monitoring reduced the 5-year risk of immunological failure from 1.6 to 1.0% and the mean time spent on failing ART from 6.6 to 3.6 months; 1% of children with CD4(+) compared with 12% with viral load monitoring switched to second-line ART. Differences became larger when assuming higher rates of virological failure. When assuming higher virological failure rates with CD4(+) than with viral load monitoring, up to 4.2% of children with CD4(+) compared with 1.5% with viral load monitoring experienced immunological failure; the mean time spent on failing ART was 27.3 months with CD4(+) monitoring and 6.0 months with viral load monitoring. Conclusion: Viral load monitoring did not affect 5-year mortality, but reduced time on failing ART, improved immunological response and increased switching to second-line ART. (C) 2014 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins
    AIDS (London, England) 10/2014; 28(16):2451-60. DOI:10.1097/QAD.0000000000000446 · 6.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: We assessed the rate of treatment failure of HIV-infected children after 12 months on antiretroviral treatment (ART) in the Paediatric IeDEA West African Collaboration according to their perinatal exposure to antiretroviral drugs for preventing mother-to-child transmission (PMTCT). Methods: A retrospective cohort study in children younger than five years at ART initiation between 2004 and 2009 was nested within the pWADA cohort, in Bamako-Mali and Abidjan-Côte d'Ivoire. Data on PMTCT exposure were collected through a direct review of children's medical records. The 12-month Kaplan-Meier survival without treatment failure (clinical or immunological) was estimated and their baseline factors studied using a Cox model analysis. Clinical failure was defined as the appearance or reappearance of WHO clinical stage 3 or 4 events or any death occurring within the first 12 months of ART. Immunological failure was defined according to the 2006 World Health Organization age-related immunological thresholds for severe immunodeficiency. Results: Among the 1035 eligible children, PMTCT exposure was only documented for 353 children (34.1%) and remained unknown for 682 (65.9%). Among children with a documented PMTCT exposure, 73 (20.7%) were PMTCT exposed, of whom 61.0% were initiated on a protease inhibitor-based regimen, and 280 (79.3%) were PMTCT unexposed. At 12 months on ART, the survival without treatment failure was 40.6% in the PMTCT-exposed group, 25.2% in the unexposed group and 18.5% in the children with unknown exposure status (p=0.002). In univariate analysis, treatment failure was significantly higher in children unexposed (HR 1.4; 95% CI: 1.0-1.9) and with unknown PMTCT exposure (HR 1.5; 95% CI: 1.2-2.1) rather than children PMTCT-exposed (p=0.01). In the adjusted analysis, treatment failure was not significantly associated with PMTCT exposure (p=0.15) but was associated with immunodeficiency (aHR 1.6; 95% CI: 1.4-1.9; p=0.001), AIDS clinical events (aHR 1.4; 95% CI: 1.0-1.9; p=0.02) at ART initiation and receiving care in Mali compared to Côte d'Ivoire (aHR 1.2; 95% CI: 1.0-1.4; p=0.04). Conclusions: Despite a low data quality, PMTCT-exposed West African children did not have a poorer 12-month response to ART than others. Immunodeficiency and AIDS events at ART initiation remain the main predictors associated with treatment failure in this operational context.
    Journal of the International AIDS Society 06/2014; 17(1):18737. DOI:10.7448/IAS.17.1.18737 · 4.21 Impact Factor

Full-text (2 Sources)

Available from
May 29, 2014