Short-term risk of disease progression in HIV-1-infected children receiving no antiretroviral therapy or zidovudine monotherapy: a meta-analysis

Early versus deferred antiretroviral therapy for children older than 1 year infected with HIV (PREDICT): a multicentre, randomised, open-label trial

BACKGROUND

The optimum time to start antiretroviral therapy for children diagnosed with HIV infection after 1 year of age is unknown. We assessed whether antiretroviral therapy could be deferred until CD4 percentages declined to less than 15% without affecting AIDS-free survival.

METHODS

In our multicentre, randomised, open-label trial at nine research sites in Thailand and Cambodia, we enrolled children aged 1-12 years who were infected with HIV and had CD4 percentages of 15-24%. Participants were randomly assigned (1:1) by a minimisation scheme to start antiretroviral therapy at study entry (early treatment group) or antiretroviral therapy to start when CD4 percentages declined to less than 15% (deferred treatment group). The primary endpoint was AIDS-free survival (based on US Centers for Disease Control and Prevention category C events) at week 144, assessed with the Kaplan-Meier analysis and the log-rank approach. This study is registered with ClinicalTrials.gov, number NCT00234091.

FINDINGS

Between March 28, 2006, and Sept 10, 2008, we enrolled 300 Thai and Cambodian children infected with HIV, with a median age of 6·4 years (IQR 3·9-8·4). 150 children were randomly allocated early antiretroviral therapy (one participant was excluded from analyses after withdrawing before week 0) and 150 children were randomly allocated deferred antiretroviral therapy. Median baseline CD4 percentage was 19% (16-22%). 69 children (46%) in the deferred treatment group started antiretroviral therapy during the study. AIDS-free survival at week 144 in the deferred treatment group was 98·7% (95% CI 94·7-99·7; 148 of 150 patients) compared with 97·9% (93·7-99·3; 146 of 149 patients) in the early treatment group (p=0·6).

INTERPRETATION

AIDS-free survival in both treatment groups was high. This low event rate meant that our study was underpowered to detect differences between treatment start times and thus additional follow-up of study participants or future studies are needed to answer this clinical question.

The unanswered question: when to initiate antiretroviral therapy in children with HIV infection

PURPOSE OF REVIEW

The question of when to initiate antiretroviral treatment for children is perhaps the most critical unanswered question in pediatric HIV therapeutics. With large numbers of children throughout the world acquiring HIV infection and with improved global access to HIV treatment it is particularly timely to consider the optimal time to initiate antiretroviral therapy in infants, children and adolescents.

RECENT FINDINGS

Early treatment can result in suppression of HIV viremia, immune preservation and prevention of disease progression. This must be balanced by the challenges of maintaining adherence to multidrug regimens, the risks of selecting drug-resistant virus, and long and short-term toxicities of medications.

SUMMARY

This review provides a framework within which to consider when to initiate children on antiretroviral treatment. A child's age and developmental status, where they live, and the goals and expectations for treatment provide a context for balancing the risks of disease progression with the risks of drug-related toxicities and viral resistance.

The CD4 lymphocyte count and risk of clinical progression

PURPOSE OF REVIEW

The CD4 lymphocyte count was identified as a key predictor of risk of AIDS defining diseases almost 20 years ago, early in the HIV epidemic. Several issues concerning its use to predict AIDS have arisen since. These include the difference between short and long-term prediction, the use of CD4 percentage compared with absolute counts, the impact of antiretroviral therapy on the predictive value of the CD4 count, the role relative to other markers such as viral load, the derivation of scores to predict AIDS diseases, the use of CD4 count as a surrogate endpoint, the role of the CD4 count nadir compared with the current value and the differential ability to predict different AIDS diseases.

RECENT FINDINGS

All the above issues have been clarified further and this process has continued through 2004 and 2005. These developments are briefly described in this review.

SUMMARY

The CD4 count remains the strongest short-term predictor of risk of AIDS so far identified in both treated and untreated patients and should continue to be a mainstay of monitoring for both untreated and treated patients.

The long-term effectiveness of generic adult fixed-dose combination antiretroviral therapy for HIV-infected Ugandan children

BACKGROUND

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

OBJECTIVE

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

METHODS

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

RESULTS

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7-13.9) and 348,846copies/mL (IQR 160,941-681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96 weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10-8.32), p=0.03}; no difference was found among those with CD4 cell percent >5-14.9% and <5%.

CONCLUSION

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.

Tuberculosis among children in Kenya: epidemiology and impact of HIV in two provinces

We collected clinical register data on children in two provinces of Kenya and conducted bivariate and multivariate analyses to assess characteristics associated with death. Among 987 children with tuberculosis (TB), pulmonary disease was diagnosed in 689 (70%) children. Final outcomes were known for 830 children, 40 (5%) of whom died during TB treatment. HIV test results were available for 670 (68%) children; 371 (55%) of whom tested positive. Only 63 of 134 (47%) of children <1 year were tested for HIV. There were no data on CD4 or anti-retroviral use. The relative risk for death for HIV-infected children compared to HIV-uninfected children was 9.3 for children <1 year [95% confidence interval (CI) 1.2-69.2], 3.9 for children aged 1-4 (95% CI 0.9-17.7) and 0.9 for children aged 5-14 (95% CI 0.3-2.6). In Kenya, HIV infection in children with TB is common, and our data suggest that HIV is particularly deadly in TB patients <1 year, the group with the lowest rate of testing. Poor data recording and reporting limit our understanding of TB in this age group. Expansion of HIV testing may improve survival, and more complete data recording and reporting will enhance our understanding of pediatric TB.

Effectiveness of antiretroviral therapy in HIV-infected children under 2 years of age

BACKGROUND

In the absence of antiretroviral therapy (ART), over 50% of HIV-infected infants progress to AIDS and death by 2 years of age. However, there are challenges to initiate ART in early life, including the possibility of drug resistance in the context of prevention of mother-to-child transmission (PMTCT) programs, a paucity of drug choices , uncertain dosing for some medications and long-term toxicities. Key management decisions include when to start ART, what regimen to start, and whether and when to switch or interrupt therapy. This review aims to summarize the currently available evidence on this topic and inform the ART management in HIV-infected children less than 2 years of age.

OBJECTIVES

To evaluate 1) when to start ART in young children; 2) what ART to start with, comparing first-line non-nucleoside reverse transcriptase inhibitor (NNRTI) and PI-based regimens; and 3) whether and when ART should be stopped or switched from a PI-based regimen to an NNRTI-based regimen.

SEARCH METHODS

We searched for published studies in the Cochrane HIV/AIDS Review Group Trials Register, The Cochrane Library, Pubmed, EMBASE and CENTRAL. We screened abstracts from relevant conference proceedings and searched for unpublished and ongoing trials in clinical trial registries (ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform).

SELECTION CRITERIA

We identified RCTs that recruited perinatally HIV-infected children under 2 years of age without restriction of setting. We rejected trials that did not include children less than 2 years of age, or did not evaluate either timing of ART initiation, choice of drug regimen or treatment switch/interruption strategy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently applied study selection criteria, assessed study quality and extracted data. Effects were assessed using the hazard ratio (HR) for time-to-event outcomes, relative risk for dichotomous outcomes and weighted mean difference for continuous outcomes.

MAIN RESULTS

Of 1921 records retrieved, 5 studies were eligible for inclusion in the review, addressing when to start treatment (n=2), what to start (n=2) and whether to switch regimen (n=1). Three ongoing studies that address the question of treatment interruption were also identified.Early infant treatment was associated with a 75% reduction (HR=0.25; 95%CI 0.12-0.51; p=0.0002) in mortality or disease progression in the one trial with sufficient power to address this question. In a smaller trial,median CD4 cell count was not significantly different between early and deferred treatment groups 12 months after ART.Regardless of previous exposure to nevirapine for PMTCT, the hazard for treatment failure was 2.01 (95%CI 1.47, 2.77) times higher in children starting ART with a NVP-based regimen compared to those starting with a LPV/r-based regimen (p<0.0001) with no clear difference in effect by age group. The hazard for virological failure was overall 2.28 (95%CI 1.55, 3.34) times higher for children starting ART with a NVP-based regimen compared to those starting with a LPV/r-based regimen (p=0.0005) with a larger difference in time to virological failure (or death) between the NVP and LPV/r-based regimens when ART was initiated in the first year of life. By contrast, increases in weight z-score (MD=0.37, 95%CI 0.08, 0.65, p=0.01) and height z-score (MD=0.23, 95%CI 0.04, 0.42, p=0.02) were larger in the NVP arm compared to the LPV/r arm .Infants starting on a LPV/r regimen but who then switched to a NVP-based regimen after a median time of 9 months on LPV/r were less likely to develop virological failure (defined as at least one VL greater than 50 copies/mL) compared with infants who started and stayed on LPV/r (HR=0.62, 95%CI 0.41, 0.92, p=0.02). However the hazard for confirmed failure at a higher viral load (>1000 copies/mL) was higher among children who switched to NVP compared to those who remained on LPV/r (HR=10.19, 95% CI 2.36, 43.94, p=0.002).

AUTHORS' CONCLUSIONS

Immediate ART reduces morbidity and mortality among infants and may improve neurodevelopmental outcome. However It remains unclear whether all children diagnosed with HIV infection between 1-2 years of age should start ART, as has been recommended by the World Health Organization on practical grounds.The available evidence suggests that a LPV/r-based first-line regimen is more potent than NVP, regardless of PMTCT exposure status. However, this finding provides a dilemma to policy-makers because higher cost, poor palatability, inconvenient formulation and cold chain requirements make LPV/r a more costly and challenging first-line regimen. An alternative approach to long-term LPV/r is switching to NVP (maintaining the NRTI backbone) once virological suppression is achieved. This strategy looked promising in the one trial undertaken, but may be difficult to implement in the absence of VL testing. Ongoing trials are exploring the possibility of starting early ART and interrupting treatment beyond the critical period of rapid disease progression and neurological development. Further evidence is urgently required to better inform policy on first-line treatment recommendations in young children and more robust data addressing non-virological outcomes are also needed.

Barriers to Initiation of Pediatric HIV Treatment in Uganda: A Mixed-Method Study

Although the advantages of early infant HIV diagnosis and treatment initiation are well established, children often present late to HIV programs in resource-limited settings. We aimed to assess factors related to the timing of treatment initiation among HIV-infected children attending three clinical sites in Uganda. Clinical and demographic determinants associated with early disease (WHO clinical stages 1-2) or late disease (stages 3-4) stage at presentation were assessed using multilevel logistic regression. Additionally, semistructured interviews with caregivers and health workers were conducted to qualitatively explore determinants of late disease stage at presentation. Of 306 children initiating first-line regimens, 72% presented late. Risk factors for late presentation were age below 2 years old (OR 2.83, P = 0.014), living without parents (OR 3.93, P = 0.002), unemployment of the caregiver (OR 4.26, P = 0.001), lack of perinatal HIV prophylaxis (OR 5.66, P = 0.028), and high transportation costs to the clinic (OR 2.51, P = 0.072). Forty-nine interviews were conducted, confirming the identified risk factors and additionally pointing to inconsistent referral from perinatal care, caregivers' unawareness of HIV symptoms, fear, and stigma as important barriers. The problem of late disease at presentation requires a multifactorial approach, addressing both health system and individual-level factors.

Utility of clinical parameters to identify HIV infection in infants below ten weeks of age in South Africa: a prospective cohort study

BACKGROUND

As HIV-infected infants have high mortality, the World Health Organization now recommends initiating antiretroviral therapy as early as possible in the first year of life. However, in many settings, laboratory diagnosis of HIV in infants is not readily available. We aimed to develop a clinical algorithm for HIV presumptive diagnosis in infants < 10 weeks old using screening data from the Children with HIV Early Antiretroviral therapy (CHER) study in South Africa.HIV-infected and HIV-uninfected exposed infants < 10 weeks of age were identified through Vertical Transmission Prevention programs. Clinical and laboratory data were systematically recorded, groups were compared using Kruskal-Wallis, analysis of variance (ANOVA), and Fisher's exact tests. Receiver Operating Characteristic (ROC) curves were compiled using combinations of clinical findings.

RESULTS

417 HIV-infected and 125 HIV-exposed, uninfected infants, median age 46 days (IQR 38-55), were included. The median CD4 percentage in HIV-infected infants was 34 (IQR 28-41)%. HIV-infected infants had lower weight-for-age, more lymphadenopathy, oral thrush, and hepatomegaly than exposed uninfected infants (Adjusted Odds Ratio 0.51, 8.8, 5.6 and 23.5 respectively; p < 0.001 for all). Sensitivity of individual signs was low (< 20%) but specificity high (98-100%). If any one of oral thrush, hepatomegaly, splenomegaly, lymphadenopathy, diaper dermatitis, weight < 50(th) centile are present, sensitivity for HIV infection amongst HIV-exposed infants was 86%. These algorithms performed similarly when used to predict severe immune suppression.

CONCLUSIONS

A combination of physical findings is helpful in identifying infants most likely to be HIV-infected. This may inform management algorithms and provide guidance for focused laboratory testing in some settings, and should be further validated in these settings and elsewhere.

Utility of total lymphocyte count as a surrogate marker for CD4 counts in HIV-1 infected children in Kenya

Background

In resource-limited settings, such as Kenya, access to CD4 testing is limited. Therefore, evaluation of less expensive laboratory diagnostics is urgently needed to diagnose immuno-suppression in children.

Objectives

To evaluate utility of total lymphocyte count (TLC) as surrogate marker for CD4 count in HIV-infected children.

Methods

This was a hospital based retrospective study conducted in three HIV clinics in Kisumu and Nairobi in Kenya. TLC, CD4 count and CD4 percent data were abstracted from hospital records of 487 antiretroviral-naïve HIV-infected children aged 1 month - 12 years.

Results

TLC and CD4 count were positively correlated (r = 0.66, p < 0.001) with highest correlation seen in children with severe immuno-suppression (r = 0.72, p < 0.001) and children >59 months of age (r = 0.68, p < 0.001). Children were considered to have severe immuno-suppression if they met the following WHO set CD4 count thresholds: age below 12 months (CD4 counts < 1500 cells/mm³), age 12-35 months (CD4 count < 750 cells/mm3), age 36-59 months (CD4 count < 350 cells/mm³, and age above 59 months (CD4 count < 200 cells/mm³). WHO recommended TLC threshold values for severe immuno-suppression of 4000, 3000, 2500 and 2000 cells/mm³ for age categories <12, 12-35, 36-59 and >59 months had low sensitivity of 25%, 23%, 33% and 62% respectively in predicting severe immuno-suppression using CD4 count as gold standard. Raising TLC thresholds to 7000, 6000, 4500 and 3000 cells/mm³ for each of the stated age categories increased sensitivity to 71%, 64%, 56% and 86%, with positive predictive values of 85%, 61%, 37%, 68% respectively but reduced specificity to 73%, 62%, 54% and 68% with negative predictive values of 54%, 65%, 71% and 87% respectively.

Conclusion

TLC is positively correlated with absolute CD4 count in children but current WHO age-specific thresholds had low sensitivity to identify severely immunosuppressed Kenyan children. Sensitivity and therefore utility of TLC to identify immuno-suppressed children may be improved by raising the TLC cut off levels across the various age categories.

Antiretroviral treatment of US children with perinatally acquired HIV infection: temporal changes in therapy between 1991 and 2009 and predictors of immunologic and virologic outcomes

BACKGROUND

Advances in therapy have allowed children with perinatal HIV infection in the United States to survive into adolescence. We sought to describe the disease status of a large cohort of such children and identify predictors of their current CD4 count and HIV viral load (VL).

METHODS

The Pediatric HIV/AIDS Cohort Study AMP Protocol is an ongoing prospective study conducted at 15 sites in the United States. Between 2007 and 2009, we enrolled a population-based sample of 451 children with perinatal HIV who were 7-16 years of age at entry.

RESULTS

The median age of subjects at entry was 12.2 years, 53% were female, 70% were African-American, and 24% Hispanic. Their median entry CD4% was 33%, and 78% had a CD4% ≥25%; 68% had a suppressed VL. The more recent birth cohorts (1994-2002) had a significantly higher CD4% over time than the earliest birth cohort (1991-1993). The significant independent predictors of a higher CD4% at entry were a suppressed entry VL, a higher nadir CD4%, and starting antiretroviral therapy at a younger age. The mean CD4% at entry for children with a nadir CD4% ≥25% was 9.5% higher than for those with a nadir CD4% <15% (P < 0.001). Independent predictors of a suppressed entry VL were membership in a recent birth cohort, male gender, highly active combination antiretroviral therapy use at entry, and fewer prior antiretroviral therapy regimens.

CONCLUSIONS

Most children with perinatal HIV maintain virologic suppression and good CD4 values. Earlier treatment results in better immune outcome.

HIV-1-resistance-associated mutations after failure of first-line antiretroviral treatment among children in resource-poor regions: a systematic review

HIV-positive children are at high risk of drug resistance, which is of particular concern in settings where antiretroviral options are limited. In this Review we explore resistance rates and patterns among children in developing countries in whom antiretroviral treatment has failed. We did a systematic search of online databases and conference abstracts and included studies reporting HIV-1 drug resistance after failure of first-line paediatric regimens in children (<18 years) in resource-poor regions (Latin America, Africa, and Asia). We retrieved 1312 citations, of which 30 studies reporting outcomes in 3241 children were eligible. Viruses with resistance-associated mutations were isolated from 90% (95% CI 88-93%) of children. The prevalence of mutations associated with nucleoside reverse transcriptase inhibitors was 80%, with non-nucleoside reverse transcriptase inhibitors was 88%, and with protease inhibitors was 54%. Methods to prevent treatment failure, including adequate paediatric formulations and affordable salvage treatment options are urgently needed.

Immunovirological response to combined antiretroviral therapy and drug resistance patterns in children: 1- and 2-year outcomes in rural Uganda

Background

Children living with HIV continue to be in urgent need of combined antiretroviral therapy (ART). Strategies to scale up and improve pediatric HIV care in resource-poor regions, especially in sub-Saharan Africa, require further research from these settings. We describe treatment outcomes in children treated in rural Uganda after 1 and 2 years of ART start.

Methods

Cross-sectional assessment of all children treated with ART for 12 (M12) and 24 (M24) months was performed. CD4 counts, HIV RNA levels, antiretroviral resistance patterns, and non-nucleoside reverse transcriptase inhibitor (NNRTI) plasma concentrations were determined. Patient adherence and antiretroviral-related toxicity were assessed.

Results

Cohort probabilities of retention in care were 0.86 at both M12 and M24. At survey, 71 (83%, M12) and 32 (78%, M24) children remained on therapy, and 84% participated in the survey. At ART start, 39 (45%) were female; median age was 5 years. Median initial CD4 percent was 11% [IQR 9-15] in children < 5 years old (n = 12); CD4 count was 151 cells/mm³ [IQR 38-188] in those ≥ 5 years old (n = 26). At M12, median CD4 gains were 11% [IQR 10-14] in patients < 5 years old, and 206 cells/mm³ [IQR 98-348] in ≥ 5 years old. At M24, median CD4 gains were 11% [IQR 5-17] and 132 cells/mm³ [IQR 87-443], respectively. Viral suppression (< 400 copies/mL) was achieved in 59% (M12) and 33% (M24) of children. Antiretroviral resistance was found in 25% (M12) and 62% (M24) of children. Overall, 29% of patients had subtherapeutic NNRTI plasma concentrations.

Conclusions

After one year of therapy, satisfactory survival and immunological responses were observed, but nearly 1 in 4 children developed viral resistance and/or subtherapeutic plasma antiretroviral drug levels. Regular weight-adjustment dosing and strategies to reinforce and maintain ART adherence are essential to maximize duration of first-line therapy in children in resource-limited countries.

Severe morbidity and mortality in untreated HIV-infected children in a paediatric care programme in Abidjan, Côte d'Ivoire, 2004-2009

Background

Clinical evolution of HIV-infected children who have not yet initiated antiretroviral treatment (ART) is poorly understood in Africa. We describe severe morbidity and mortality of untreated HIV-infected children.

Methods

All HIV-infected children enrolled from 2004-2009 in a prospective HIV programme in two health facilities in Abidjan, Côte d'Ivoire, were eligible from their time of inclusion. Risks of severe morbidity (the first clinical event leading to death or hospitalisation) and mortality were documented retrospectively and estimated using cumulative incidence functions. Associations with baseline characteristics were assessed by competing risk regression models between outcomes and antiretroviral initiation.

Results

405 children were included at a median age of 4.5 years; at baseline, 66.9% were receiving cotrimoxazole prophylaxis, and 27.7% met the 2006 WHO criteria for immunodeficiency by age. The risk of developing a severe morbid event was 14% (95%CI: 10.7 - 17.8) at 18 months; this risk was lower in children previously exposed to any prevention of mother-to-child-transmission (PMTCT) intervention (adjusted subdistribution hazard ratio [sHR]: 0.16, 95% CI: 0.04 - 0.71) versus those without known exposure. Cumulative mortality reached 5.5% (95%CI: 3.5 - 8.1) at 18 months. Mortality was associated with immunodeficiency (sHR: 6.02, 95% CI: 1.28-28.42).

Conclusions

Having benefited from early access to care minimizes the severe morbidity risk for children who acquire HIV. Despite the receipt of cotrimoxazole prophylaxis, the risk of severe morbidity and mortality remains high in untreated HIV-infected children. Such evidence adds arguments to promote earlier access to ART in HIV-infected children in Africa and improve care interventions in a context where treatment is still not available to all.

Presumptive diagnosis of severe HIV infection to determine the need for antiretroviral therapy in children less than 18 months of age

OBJECTIVE

To develop a new algorithm for the presumptive diagnosis of severe disease associated with human immunodeficiency virus (HIV) infection in children less than 18 months of age for the purpose of identifying children who require antiretroviral therapy (ART).

METHODS

A conditional probability model was constructed and non-virologic parameters in various combinations were tested in a hypothetical cohort of 1000 children aged 6 weeks, 6 months and 12 months to assess the sensitivity, specificity, and positive and negative predictive values of these algorithms for identifying children in need of ART. The modelled parameters consisted of clinical criteria, rapid HIV antibody testing and CD4+ T-lymphocyte (CD4) count.

FINDINGS

In children younger than 18 months, the best-performing screening algorithm, consisting of clinical symptoms plus antibody testing plus CD4 count, showed a sensitivity ranging from 71% to 80% and a specificity ranging from 92% to 99%. Positive and negative predictive values were between 61% and 97% and between 95% and 96%, respectively. In the absence of virologic tests, this alternate algorithm for the presumptive diagnosis of severe HIV disease makes it possible to correctly initiate ART in 91% to 98% of HIV-positive children who are at highest risk of dying.

CONCLUSION

The algorithms presented in this paper have better sensitivity and specificity than clinical parameters, with or without rapid HIV testing, for the presumptive diagnosis of severe disease in HIV-positive children less than 18 months of age. If implemented, they can increase the number of HIV-positive children successfully initiated on ART.

Inadequate coordination of maternal and infant HIV services detrimentally affects early infant diagnosis outcomes in Lilongwe, Malawi

OBJECTIVE

To assess the continuity of care and outcome of pediatric HIV prevention, testing, and treatment services, focusing on early infant diagnosis with DNA polymerase chain reaction (PCR).

DESIGN

A retrospective observational cohort.

METHODS

Maternal HIV antibody, infant HIV DNA PCR test results, and outcome data from HIV-infected infants from the prevention of mother-to-child transmission, early infant diagnosis, and pediatric HIV treatment programs operating in Lilongwe, Malawi, between 2004 and 2008 were collected, merged, and analyzed.

RESULTS

Of the 14,669 pregnant women who tested HIV antibody positive, 7875 infants (53.7%) received HIV DNA PCR testing. One thousand eighty-four infants (13.8%) were HIV infected. Three hundred twenty (29.5%) children enrolled into pediatric HIV care, with 202 (63.1%) at the Baylor Center of Excellence. Among these, antiretroviral therapy was initiated on 110 infants (54.5%) whose median age was 9.1 months (interquartile range, 5.4-13.8) and a median of 2.5 months (interquartile range, 1.4-5.2) after HIV clinic registration. Sixty-nine HIV-infected infants (34.2%) died or were lost by December 2008. Initiation of antiretroviral therapy increased the likelihood of survival 7-fold (odds ratio, 7.1; 95% confidence interval, 3.68 to 13.70).

CONCLUSIONS

Separate programs for maternal and infant HIV prevention and care services demonstrated high attrition rates of HIV-exposed and HIV-infected infants, elevated levels of mother-to-child transmission, late infant diagnosis, delayed pediatric antiretroviral therapy initiation, and high HIV-infected infant mortality. Antiretroviral therapy increased HIV-infected infant survival, emphasizing the urgent need for improved service coordination and strategies that increase access to infant HIV diagnosis, improve patient retention, and reduce antiretroviral therapy initiation delays.

Derivation of parameters used in Spectrum for eligibility for antiretroviral therapy and survival on antiretroviral therapy

Background

The Spectrum projection package uses estimates of national HIV incidence, demographic data and other assumptions to describe the consequences of the HIV epidemic in low and middle-income countries. The default parameters used in Spectrum are updated every 2 years as new evidence becomes available to inform the model. This paper reviews the default parameters that define the course of HIV progression among adults and children in Spectrum.

Methods

For adults, data available from published and grey literature and data from the ART-LINC International epidemiologic Database to Evaluate AIDS (IeDEA) collaboration were combined to estimate survival among those who started antiretroviral therapy (ART). For children, a review of published material on survival on ART and survival on ART and cotrimoxazole was used to derive survival probabilities. Historical data on the distribution of CD4 cell counts and CD4 cell percentages by age among children who were not treated (before treatment was available) were used to progress children from seroconversion to different CD4 cell levels.

Results

Based on the updated evidence estimated survival among adults aged over 15 years in the first year on ART was 86%, while in subsequent years survival was estimated at 90%. Survival among children during the first year on ART was estimated to be 85% and for subsequent years 93%.

Discussion

The revised default parameters based on additional data will make Spectrum estimates more accurate than previous rounds of estimates.

Pediatric antiretroviral therapy

The rate of perinatal HIV transmission has decreased significantly in developed countries. However, worldwide, it remains the main source of HIV infection within the pediatric population. Recent advances as a result of findings from clinical trials, viral resistance testing and the advent of new drugs have increased the options for initial treatment regimens. This article provides an overview of antiretroviral therapy in treatment-naive children, including recent pediatric data and updated guidelines from the NIH. It also provides information on new drugs approved for the pediatric age group, dosage information, drug resistance testing and monitoring suggestions for children and adolescents receiving antiretroviral therapy. Special issues pertaining to adherence, disclosure and contraception are also highlighted.

Long-term survival of HIV-infected children receiving antiretroviral therapy in Thailand: a 5-year observational cohort study

BACKGROUND

There are scarce data on the long-term survival of human immunodeficiency virus (HIV)-infected children receiving antiretroviral therapy (ART) in lower-middle income countries beyond 2 years of follow-up.

METHODS

Previously untreated children who initiated ART on meeting immunological and/or clinical criteria were followed in a prospective cohort in Thailand. The probability of survival up to 5 years from initiation was estimated using Kaplan-Meier methods, and factors associated with mortality were assessed using Cox regression analyses.

RESULTS

Five hundred seventy-eight children received ART; of these, 111 (19.2%) were followed since birth. At start of ART (baseline), the median age was 6.7 years, 128 children (22%) were aged <2 years, and the median CD4 cell percentage was 7%. Median duration of follow-up was 53 months; 42 children (7%) died, and 38 (7%) were lost to follow-up. Age <12 months, low CD4 cell percentage, and low weight-for-height z score at ART initiation were independently associated with mortality (P < .001). The probability of survival among infants aged <12 months at baseline was 84.3% at 1 year and 76.7% at 5 years of ART, compared with 95.7% and 94.8%, respectively, among children aged ≥1 year. Low CD4 cell percentage and wasting at baseline had a strong association with mortality among older children but weak or no association among infants.

CONCLUSIONS

Children who initiated ART as infants after meeting immunological and/or clinical criteria had a high risk of mortality which persisted beyond the first year of therapy. Among older children, those with severe wasting or low CD4 cell percentage at treatment initiation were at high risk of mortality during the first 6 months of therapy. These findings support the scale-up of early HIV diagnosis and immediate treatment in infants, before advanced disease progression in older children.

The clinical care of the HIV-1-infected infant

Despite well-established strategies to decrease the mother-to-child transmission of HIV-1, new perinatal infections continue to occur globally, reflecting marked disparities in access to health care. Once HIV-1 infection has been established in an infant, the combination of early initiation of antiretroviral therapy and prophylaxis against Pneumocystis jiroveci pneumonia is paramount to reducing disease progression. This article reviews the recommendations and evidence for the treatment of HIV-1-infected infants.

Short-term risk of HIV disease progression and death in Ugandan children not eligible for antiretroviral therapy

BACKGROUND

Increasing numbers of HIV-infected children not yet eligible for antiretroviral therapy (ART) are entering health care in Africa. We sought to characterize the risk of short-term disease progression in this population.

METHODS

In a cohort of HIV-infected ART-naive and -ineligible Ugandan children older than 1 year, the rates of clinical/immunologic progression within 2 years were assessed using Kaplan-Meier survival analysis and multivariate Cox proportional-hazards modeling.

RESULTS

Among 192 children (mean age: 6.4 years, CD4%:25), 19% progressed within 2 years by World Health Organization stage 3/4 event (n = 22), death (n = 3), or World Health Organization-defined CD4 threshold for ART initiation (n = 12). Significant univariate predictors were CD4% [hazard ratio (HR) = 2.0 per 10% decrease, P = 0.005], HIV RNA level (HR = 2.4 per log10 increase, P = 0.002), male gender (HR = 2.0, P = 0.04), age < 3 years (HR = 3.7, P = 0.001), CD4 activation (%CD4+ CD38+ HLADR+) (HR = 1.6 per 10% increase, P = 0.05), and CD8 activation (%CD8+ CD38+ HLADR+) (HR = 1.3 per 10% increase, P = 0.05] (HR = 1.3, P = 0.5). In multivariate analysis, CD4% (HR = 2.0, P = 0.034), HIV RNA level (HR = 1.8, P = 0.013), and age < 3 years (HR = 3.0, P = 0.008) were independently predictive. Children with HIV RNA >10 copies per milliliter and CD4% <25 had progression rates of 29% (1 year) and 34% (2 years).

CONCLUSIONS

Even with frequent CD4 monitoring, HIV-infected Ugandan children experienced significant clinical events while ineligible for ART per WHO 2006 guidelines.

CD4 cell count criteria to determine when to initiate antiretroviral therapy in human immunodeficiency virus-infected children

We evaluated the validity of CD4 count against CD4% criteria of 2008 World Health Organization guideline for initiating antiretroviral therapy using the data of 446 human immunodeficiency virus-infected Asian children aged 1 to 12 years who were screened to the Pediatric Randomized of Early versus Deferred Initiation in Cambodia and Thailand study. The overall sensitivity and specificity were 34% and 98%, respectively. Using the current CD4 count criteria would globally result in 66% missed opportunity to initiate treatment in a timely fashion. Raising CD4 count thresholds should be considered to increase its sensitivity and reduce missed opportunity.

PENTA 2009 guidelines for the use of antiretroviral therapy in paediatric HIV-1 infection

PENTA Guidelines aim to provide practical recommendations for treating children with HIV infection in Europe. Changes to guidance since 2004 have been informed by new evidence and by expectations of better outcomes following the ongoing success of antiretroviral therapy (ART). Participation in PENTA trials of simplifying treatment is encouraged. The main changes are in the following sections: 'When to start ART': Treatment is recommended for all infants, and at higher CD4 cell counts and percentages in older children, in line with changes to adult guidelines. The number of age bands has been reduced to simplify and harmonize with other paediatric guidelines. Greater emphasis is placed on CD4 cell count in children over 5 years, and guidance is provided where CD4% and CD4 criteria differ. 'What to start with': A three-drug regimen of two nucleoside reverse transcriptase inhibitors (NRTIs) with either a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a boosted protease inhibitor (PI) remains the first choice combination. Lamivudine and abacavir are the NRTI backbone of choice for most children, based on long-term follow-up in the PENTA 5 trial. Stavudine is no longer recommended. Whether to start with an NNRTI or PI remains unclear, but PENPACT 1 trial results in 2009 may help to inform this. All PIs should be ritonavir boosted. Recommendations on use of resistance testing, therapeutic drug monitoring and HLA testing draw from data in adults and from European paediatric cohort studies. Recently updated US and WHO paediatric guidelines provide more detailed review of the evidence base. Differences between guidelines are highlighted and explained.

Discordance between CD4 cell count and CD4 cell percentage: implications for when to start antiretroviral therapy in HIV-1 infected children

OBJECTIVE

Antiretroviral therapy (ART) guidelines for HIV-1-infected children specify both absolute CD4 cell count and CD4 percentage thresholds at which consideration should be given to initiating ART. This leads to clinical dilemma when one marker is below the threshold, whereas the other is above.

DESIGN

Data were obtained on a large group of children followed longitudinally in trials and cohort studies in Europe and the USA. Follow-up was censored 6 months after the start of any antiretroviral drug other than zidovudine monotherapy.

METHODS

Discordance between CD4 cell count and percentage was defined in relation to ART initiation thresholds in World Health Organization (WHO) and European paediatric treatment guidelines. The relative prognostic value of CD4 cell count and percentage for progression to AIDS/death was investigated using time-updated Cox proportional hazards models, stratified by age.

RESULTS

Among 3345 children, with a total of 21,815 pairs of CD4 measurements analysed, 980 developed AIDS and/or died after a median follow-up of 1.7 years. Over one-half of children had discordant values of CD4 cell markers at the first visit when one or both treatment thresholds were crossed and approximately one-third had the same pattern of discordance at a subsequent measurement. Models suggested that CD4 percentage had little or no prognostic value over and above that contained in CD4 cell count, irrespective of age.

CONCLUSIONS

More emphasis should be placed on CD4 cell count than on CD4 percentage in deciding when to start ART in HIV-1-infected children.

Antiretroviral therapy outcomes in resource-limited settings for HIV-infected children <5 years of age

OBJECTIVE

We describe medium-term outcomes for young children receiving antiretroviral therapy (ART) in resource-limited countries.

METHODS

Analyses were conducted on surveillance data for children <5 years of age receiving ART (initiated April 2002 to January 2008) in 48 HIV/AIDS treatment programs in Africa and Asia. Primary outcome measures were probability of remaining in care, probability of developing World Health Organization stage 4 clinical events, rate of switching to second-line ART, and drug toxicity, compared at 6, 12, 24, and 36 months of ART.

RESULTS

Of 3936 children (90% in Africa) initiating ART, 9% were <12 months, 50% were 12 to 35 months, and 41% were 36 to 59 months of age. The median time of ART was 10.5 months. Probabilities of remaining in care after 12, 24, and 36 months of ART were 0.85, 0.80, and 0.75, respectively. Compared with children 36 to 59 months of age at ART initiation, probabilities of remaining in care were significantly lower for children <12 months of age. Overall, 55% and 69% of deaths and losses to follow-up occurred in the first 3 and 6 months of ART, respectively. Probabilities of developing stage 4 clinical events after 12, 24, and 36 months of ART were 0.03, 0.06, and 0.09, respectively. Only 33 subjects (0.8%) switched to second-line regimens, and 151 (3.8%) experienced severe drug toxicities.

CONCLUSIONS

Large-scale ART for children <5 years of age in resource-limited settings is feasible, with encouraging clinical outcomes, but efforts should be increased to improve early HIV diagnosis and treatment.

Short-term micronutrient supplementation reduces the duration of pneumonia and diarrheal episodes in HIV-infected children

The duration of pneumonia and of diarrhea is reported to be longer in HIV-infected than in uninfected children. We assessed the effect of a multi-micronutrient supplement on the duration of hospitalization in HIV-infected children. In a double-blind, randomized trial, HIV-infected children (4-24 mo) who were hospitalized with diarrhea or pneumonia were enrolled (n = 118) and given a daily dose of a multi-micronutrient supplement (containing vitamins A, B complex, C, D, E, and folic acid, as well as copper, iron, and zinc at levels based on recommended daily allowances) or a placebo until discharge from the hospital. Children's weights and heights were measured after enrollment and micronutrient concentrations were measured before discharge. On recovery from diarrhea or pneumonia, the children were discharged and the duration of hospitalization was noted. Anthropometric indices and micronutrient concentrations did not differ between children who received supplements and those who received placebos. Overall, the duration of hospitalization was shorter (P < 0.05) among children who were receiving supplements (7.3 +/- 3.9 d) (mean +/- SD) than in children who were receiving placebos (9.0 +/- 4.9); this was independent of admission diagnosis. In children admitted with diarrhea, the duration of hospitalization was 1.6 d (19%) shorter among children receiving supplements than in those receiving placebos, and hospitalization for pneumonia was 1.9 d (20%) shorter among children receiving supplements. Short-term multi-micronutrient supplementation significantly reduced the duration of pneumonia or diarrhea in HIV-infected children who were not yet receiving antiretroviral therapy and who remained alive during hospitalization.

Task shifting routine inpatient pediatric HIV testing improves program outcomes in urban Malawi: a retrospective observational study

BACKGROUND

This study evaluated two models of routine HIV testing of hospitalized children in a high HIV-prevalence resource-constrained African setting. Both models incorporated "task shifting," or the allocation of tasks to the least-costly, capable health worker.

METHODS AND FINDINGS

Two models were piloted for three months each within the pediatric department of a referral hospital in Lilongwe, Malawi between January 1 and June 30, 2008. Model 1 utilized lay counselors for HIV testing instead of nurses and clinicians. Model 2 further shifted program flow and advocacy responsibilities from counselors to volunteer parents of HIV-infected children, called "patient escorts." A retrospective review of data from 6318 hospitalized children offered HIV testing between January-December 2008 was conducted. The pilot quarters of Model 1 and Model 2 were compared, with Model 2 selected to continue after the pilot period. There was a 2-fold increase in patients offered HIV testing with Model 2 compared with Model 1 (43.1% vs 19.9%, p<0.001). Furthermore, patients in Model 2 were younger (17.3 vs 26.7 months, p<0.001) and tested sooner after admission (1.77 vs 2.44 days, p<0.001). There were no differences in test acceptance or enrollment rates into HIV care, and the program trends continued 6 months after the pilot period. Overall, 10244 HIV antibody tests (4779 maternal; 5465 child) and 453 DNA-PCR tests were completed, with 97.8% accepting testing. 19.6% of all mothers (n = 1112) and 8.5% of all children (n = 525) were HIV-infected. Furthermore, 6.5% of children were HIV-exposed (n = 405). Cumulatively, 72.9% (n = 678) of eligible children were evaluated in the hospital by a HIV-trained clinician, and 68.3% (n = 387) successfully enrolled into outpatient HIV care.

CONCLUSIONS/SIGNIFICANCE

The strategy presented here, task shifting from lay counselors alone to lay counselors and patient escorts, greatly improved program outcomes while only marginally increasing operational costs. The wider implementation of this strategy could accelerate pediatric HIV care access in high-prevalence settings.

Treatment of HIV infection: Swedish recommendations 2009

On 4 previous occasions, in 2002, 2003, 2005 and 2007, the Swedish Medical Products Agency (Läkemedelsverket) and the Swedish Reference Group for Antiviral Therapy (RAV) have jointly published recommendations for the treatment of HIV infection. In November 2008, an expert group under the guidance of RAV once more revised the guidelines, of which this is a translation into English. The most important updates in the present guidelines include the following: (a) treatment initiation is now recommended at a CD4 cell count of approximately 350/microl; (b) new recommendations for first-line therapy: abacavir/lamivudine or tenofovir/emtricitabine in combination with efavirenz or a boosted protease inhibitor (PI/r); (c) an increased focus on reducing the use of antiretroviral drugs that may cause lipoatrophy; (d) an emphasis on quality assurance of HIV care through the use of InfCare HIV; (e) considerably altered recommendations for the initiation of antiretroviral therapy in children. All infants (<1 y) should start antiretroviral therapy, regardless of immune status. Also, absolute CD4+ cell counts, rather than percentage, may be used to guide treatment initiation in children above the age of 5 y.

Response to planned treatment interruptions in HIV infection varies across childhood

OBJECTIVE

To evaluate clinical, immunological and virological consequences of CD4-guided antiretroviral therapy (ART) planned treatment interruptions (PTIs) compared with continuous therapy in children with chronic HIV infection in the Paediatric European Network for Treatment of AIDS 11 trial.

DESIGN

This was a multicentre, 72-week, open, randomized, phase II trial.

METHODS

One hundred and nine children with HIV-RNA below 50 copies/ml and CD4% of at least 30% (2-6 years) or at least 25% and CD4 cell count of at least 500 cells/microl (7-15 years) were randomized to continuous therapy (53) or PTI (56). In PTI, ART was restarted if confirmed CD4% was less than 20% or more than 48 weeks had been spent off ART. The primary outcome was Centers for Disease Control and Prevention (CDC) stage C event, death or CD4% less than 15% (and CD4 cell count less than 200 cells/microl for children aged 7-15 years).

RESULTS

At baseline, median (interquartile range) age was 9 (6-12) years, CD4% 37% (33-41), CD4 cell count 966 (793-1258) cells/microl, nadir CD4% before combination ART 18% (10-27), time on ART 6 (3-6) years and 26% were CDC stage C. After median (range) 130 (33-180) weeks of follow-up, 4 versus 48% of time was spent off ART in continuous therapy and PTI, respectively. No child died or had a new CDC stage C event; one (2%) continuous therapy versus four (7%) PTI children had a primary outcome based on CD4%/cell count (P = 0.2). Lower nadir CD4% predicted faster CD4% decline after stopping ART. Younger age and higher nadir CD4% predicted being off ART for at least 48 weeks and better CD4% recovery following PTI.

CONCLUSION

In this first paediatric trial of PTI, there were no serious clinical outcomes. Younger children had better CD4% recovery after PTIs. Immunology substudies and long-term follow-up in Paediatric European Network for Treatment of AIDS 11 trial are ongoing. Further research into the role of treatment interruption in children is required, particularly, as guidelines now recommend early ART for all infected infants.

Lymphocyte subsets in healthy Malawians: implications for immunologic assessment of HIV infection in Africa

Background

CD4⁺T lymphocyte measurements are the most important indicator of mortality in HIV-infected individuals in resource-limited settings. There is currently a lack of comprehensive immunophenotyping data from African populations to guide the immunologic assessment of HIV infection.

Objective

To quantify variation in absolute and relative lymphocyte subsets with age in healthy Malawians.

Methods

Lymphocyte subsets in peripheral blood of 539 healthy HIV-uninfected Malawians stratified by age were enumerated by flow cytometry.

Results

B and T–lymphocyte and T-lymphocyte subset absolute concentrations peaked in early childhood then decreased to adult levels, whereas lymphocyte subset proportions demonstrated much less variation with age. Adult lymphocyte subsets were similar to those in developed countries. In contrast, high B-lymphocyte and CD8⁺T-lymphocyte levels among children under 2 years, relative to those in developed countries, resulted in low CD4⁺T-lymphocyte percentages that varied little between 0 and 5 years (35% to 39%). The CD4⁺T-lymphocyte percentages in 35% of healthy children under 1 year and 18% of children age 1 to 3 years were below the World Health Organization threshold defining immunodeficiency in HIV-infected children in resource-limited settings. Thirteen percent of healthy children under 18 months old had a CD4:CD8T-lymphocyte ratio <1.0, which is commonly associated with HIV infection. All immunologic parameters except absolute natural killer lymphocyte concentration varied significantly with age, and percentage and overall absolute CD4⁺T-lymphocyte counts were higher in females than males.

Conclusion

Although lymphocyte subsets in Malawian adults are similar to those from developed countries, CD4⁺T-lymphocyte percentages in young children are comparatively low. These findings need to be considered when assessing the severity of HIV-related immunodeficiency in African children under 3 years.

Update on antiretroviral therapy in paediatrics

This review provides an update on the most relevant issues concerning the current management of HIV infection in infants and children. Tremendous progress has been made over the last few years to diagnose and treat infants and children with HIV infection, yet much remains to be done. Every day there are nearly 1150 new infections in children under 15 years of age, more than 90% of them occurring in the developing world and most being the result of transmission from mother-to-child (WHO 2008). The comprehensive approach to preventing mother-to-child transmission (MTCT) has clearly reduced the number of children acquiring the infection in Western countries; while a further reduction of mother-to-child transmission should be aimed for personalized setting, specific intervention needs to be put in place and new efforts are now required in order to optimise treatment and care in HIV-infected children. The prompt initiation of treatment and a careful selection of first-line regimen, which considers potency as well as tolerability remain central. In addition, occurrence and prevention of opportunistic infections, adherence as well as long-term psychosocial consequences are becoming more and more relevant in the era of effective antiretroviral therapy. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of Antiretroviral Drug Discovery and Development, vol. 85, issue 1, 2010.

Antiretroviral treatment of HIV infection: Swedish recommendations 2007

On 3 previous occasions, in 2002, 2003 and 2005, the Swedish Medical Products Agency (Läkemedelsverket) and the Swedish Reference Group for Antiviral Therapy (RAV) have jointly published recommendations for the treatment of HIV infection. An expert group, under the guidance of RAV, has now revised the text again. Since the publication of the previous treatment recommendations, 1 new drug for the treatment of HIV has been approved - the protease inhibitor (PI) darunavir (Prezista). Furthermore, 3 new drugs have become available: the integrase inhibitor raltegravir (MK-0518), the CCR5-inhibitor maraviroc (Celsentri), both of which have novel mechanisms of action, and the non-nucleoside reverse transcriptase inhibitor (NNRTI) etravirine (TMC-125). The new guidelines differ from the previous ones in several respects. The most important of these are that abacavir is now preferred to tenofovir and zidovudine, as a first line drug in treatment-naïve patients, and that initiation of antiretroviral treatment is now recommended before the CD4 cell count falls below 250/microl, rather than 200/microl. Furthermore, recommendations on the treatment of HIV infection in children have been added to the document. As in the case of the previous publication, recommendations are evidence-graded in accordance with the Oxford Centre for Evidence Based Medicine, 2001 (see http://www.cebm.net/levels_of_evidence.asp#levels).

Early treatment of HIV: implications for resource-limited settings

PURPOSE OF REVIEW

We review the current literature supporting adoption of higher CD4 thresholds for initiation of antiretroviral treatment and survey progress in adoption of early treatment policies in resource-limited settings. We highlight some of the challenges and opportunities implementation of early treatment will bring.

RECENT FINDINGS

The initial success of combination antiretroviral treatment resulted in the recommendation to treat early all individuals with HIV. However, the gradual realization that antiretroviral treatment was associated with toxicity led to a more tempered approach. Recent cohort studies and some clinical trials have shown that delaying treatment is associated with increased morbidity and mortality.

SUMMARY

Early treatment is routinely practiced in developed countries. Now, early treatment is being adopted as a strategy in many resource-limited settings. The implications of this policy shift are not known, but we predict early treatment will have important consequences for the health system, the individual, and the community. Whereas these consequences will bring significant challenges, the increased numbers of HIV-infected individuals on treatment will result in many new opportunities - antiretroviral treatment will become less expensive, systems to deliver chronic care will be strengthened, and the policy shift will focus greater attention on pregnant women and children. Finally, some authors postulate that early treatment may impact HIV transmission.

Psychiatric diagnosis and antiretroviral adherence among adolescent Medicaid beneficiaries diagnosed with human immunodeficiency virus/acquired immunodeficiency syndrome

Research on adults with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) has suggested that psychiatric and substance abuse comorbidities are prevalent in this population, and that these may sometimes be associated with use of antiretroviral therapy (ART) and adherence. For adolescents with HIV/AIDS, much less is known about patterns of mental health comorbidity, and even fewer data are available that compare them to socioeconomically comparable youth without HIV/AIDS. Using medical and pharmacy data from 1999 to 2000 Medicaid claims (Medicaid Analytic Extract) from 4 states for beneficiaries aged 12 to 17 years, we identified 833 youth under care for HIV/AIDS meeting study criteria within the HIV/AIDS group, receipt of ART was less likely for youth who had diagnoses of substance abuse, conduct disorders, or emotional disorders than for others. Once ART was initiated, adherence did not significantly differ between adolescents living with a psychiatric condition, and those who were not, with the exception of an association between conduct disorder and lower adherence. Among those with HIV/AIDS, ART use and adherence were more common among youth with higher rates of service use, regardless of psychiatric status. Associations between race and adherence varied by gender: compared with their white counterparts, minority girls had lower, and minority boys had higher adherence.

Making a working clinical diagnosis of HIV infection in infants in Zimbabwe

OBJECTIVES

Clinical algorithms can be helpful in decisions about treatment and feeding options in infancy, but have had limited exposure to real data. This analysis uses data from a large clinical trial to test such algorithms, and thereby develop a successor which performs usefully in poor countries with high HIV-prevalence.

METHODS

The ZVITAMBO trial followed 14 110 mother-baby pairs through infancy. 32% of mothers were HIV-positive. Infants were HIV tested regularly using DNA PCR. Clinical signs were evaluated in terms of identifying HIV-infection at 6 weeks, 6 and 12 months, using Zimbabwean, South African, and WHO generic adaptations of the WHO integrated management of childhood illness HIV algorithm. A modification, in which HIV-exposed infants are first divided into being at least or less than median weight-for-age, was derived and evaluated.

RESULTS

At 6 weeks 65% of all infected babies are less than median weight-for-age. Adding at least two clinical signs reduces sensitivity to 20% but those identified are 1.5 (95% CI 1.1-2.1) times more likely to die by 6 months than other infected infants. At 6 months, 86% of uninfected babies of HIV-infected mothers can be identified by selecting those whose weight is greater than median or, if less than median, who exhibit <2 clinical signs.

CONCLUSIONS

In poor settings a simple clinical algorithm can identify children with probable HIV infection, especially those at risk of early death, who can then be referred for further testing and care, including highly active antiretroviral therapy. Most infants who are HIV-uninfected can be identified at 6 months and provided with support to maintain infection-free survival, including focussed infant-feeding counselling.

Evaluation and management of the infant exposed to HIV-1 in the United States

The pediatrician plays a key role in the prevention of mother-to-child transmission of HIV-1 infection. For infants born to women with HIV-1 infection identified during pregnancy, the pediatrician ensures that antiretroviral prophylaxis is provided to the infant to decrease the risk of acquiring HIV-1 infection and promotes avoidance of postnatal HIV-1 transmission by advising HIV-1-infected women not to breastfeed. The pediatrician should perform HIV-1 antibody testing for infants born to women whose HIV-1 infection status was not determined during pregnancy or labor. For HIV-1-exposed infants, the pediatrician monitors the infant for early determination of HIV-1 infection status and for possible short- and long-term toxicity from antiretroviral exposures. Provision of chemoprophylaxis for Pneumocystis jiroveci pneumonia and support of families living with HIV-1 by providing counseling to parents or caregivers are also important components of care.

Antiretroviral therapy during infancy: essential intervention for resource-limited settings

EVALUATION OF: Prendergast A, Mphatswe W, Tudor-Williams G et al. Early virological suppression with three-class antiretroviral therapy in HIV-infected African infants. AIDS 22, 1333-1343 (2008). There is limited information regarding the outcome of infants treated with highly active antiretroviral therapy (HAART) in middle- and low-income countries. The mean/median age of children enrolled on HAART in these countries is generally high; however, it is acknowledged that untreated HIV-infected children under 2 years of age, including infected infants, are an extremely vulnerable group. This article assessed the findings of a recently published paper describing the outcome of 63 infants randomized to commence immediate or deferred HAART in a resource-poor setting and documented favorable short-term outcome in both groups, with correspondingly high adherence rates. The recent change in global treatment guidelines, recommending that all HIV-infected infants should be commenced on HAART soon after diagnosis, irrespective of their clinical status and/or immunological severity, is discussed in relation to the key findings of the article.

Early antiretroviral therapy and mortality among HIV-infected infants

BACKGROUND

In countries with a high seroprevalence of human immunodeficiency virus type 1 (HIV-1), HIV infection contributes significantly to infant mortality. We investigated antiretroviral-treatment strategies in the Children with HIV Early Antiretroviral Therapy (CHER) trial.

METHODS

HIV-infected infants 6 to 12 weeks of age with a CD4 lymphocyte percentage (the CD4 percentage) of 25% or more were randomly assigned to receive antiretroviral therapy (lopinavir-ritonavir, zidovudine, and lamivudine) when the CD4 percentage decreased to less than 20% (or 25% if the child was younger than 1 year) or clinical criteria were met (the deferred antiretroviral-therapy group) or to immediate initiation of limited antiretroviral therapy until 1 year of age or 2 years of age (the early antiretroviral-therapy groups). We report the early outcomes for infants who received deferred antiretroviral therapy as compared with early antiretroviral therapy.

RESULTS

At a median age of 7.4 weeks (interquartile range, 6.6 to 8.9) and a CD4 percentage of 35.2% (interquartile range, 29.1 to 41.2), 125 infants were randomly assigned to receive deferred therapy, and 252 infants were randomly assigned to receive early therapy. After a median follow-up of 40 weeks (interquartile range, 24 to 58), antiretroviral therapy was initiated in 66% of infants in the deferred-therapy group. Twenty infants in the deferred-therapy group (16%) died versus 10 infants in the early-therapy groups (4%) (hazard ratio for death, 0.24; 95% confidence interval [CI], 0.11 to 0.51; P<0.001). In 32 infants in the deferred-therapy group (26%) versus 16 infants in the early-therapy groups (6%), disease progressed to Centers for Disease Control and Prevention stage C or severe stage B (hazard ratio for disease progression, 0.25; 95% CI, 0.15 to 0.41; P<0.001). Stavudine was substituted for zidovudine in four infants in the early-therapy groups because of neutropenia in three infants and anemia in one infant; no drugs were permanently discontinued. After a review by the data and safety monitoring board, the deferred-therapy group was modified, and infants in this group were all reassessed for initiation of antiretroviral therapy.

CONCLUSIONS

Early HIV diagnosis and early antiretroviral therapy reduced early infant mortality by 76% and HIV progression by 75%. (ClinicalTrials.gov number, NCT00102960.)

Continuous improvement in the immune system of HIV-infected children on prolonged antiretroviral therapy

BACKGROUND

The goal of HAART is to promote reconstitution of CD4+ T cells and other immune responses. We evaluated the extent and the kinetics of immune reconstitution in HIV-infected children over 144 weeks of successful HAART.

METHODS

Thirty-seven children receiving their first HAART regimen had plasma HIV RNA; T cells and subpopulations; T-cell rearrangement excision circles (TREC) DNA; candida, HIVCD4 and HIVCD8 enzyme-linked immunospot measured at regular intervals.

RESULTS

Plasma HIV RNA became undetectable in 81% of patients at 24 weeks and remained undetectable in 77% at 144 weeks. In contrast, CD4+% continuously increased. Distribution of T-cell subpopulations changed rapidly during the first 48 weeks of HAART and more slowly thereafter. At 144 weeks, total, naive and activated CD4+% and naive CD8+% of HIV-infected children were not significantly different from those of healthy age-matched controls, whereas total and activated CD8+% remained elevated. CD4 and CD8 TREC content increased only during the first 48 weeks of HAART. They positively correlated with each other and with total CD4+%, naive CD4+% and naive CD8+%. Candida and HIVCD4 enzyme-linked immunospot increased over time reaching peak values at 48 weeks and 144 weeks, respectively. HIVCD8 enzyme-linked immunospot decreased in magnitude over 144 weeks of HAART but retained its breadth. Baseline CD4+% positively correlated with CD4+% and with functional immune reconstitution at week 144, whereas baseline TREC correlated with TREC at week 144.

CONCLUSION

HIV-infected children acquired normal distribution of CD4 T cells and other subpopulations and recovered CD4-mediated HIV immunity after 144 weeks of HAART.

A feasibility study of immediate versus deferred antiretroviral therapy in children with HIV infection

OBJECTIVE

To evaluate the feasibility of a large immediate versus deferred antiretroviral therapy (ART) study in children.

METHODS

We conducted an open-label pilot randomized clinical trial study in 43 Thai children with CD4 15 to 24% of starting generic AZT/3TC/NVP immediately (Arm 1) or deferring until CD4 < 15% or CDC C (Arm 2). Primary endpoints were recruitment rate, adherence to randomized treatment and retention in trial. Secondary endpoints were % with CDC C or CD4 < 15%. Children were in the trial until the last child reached 108 weeks. Intention to treat and on treatment analyses were performed.

RESULTS

Recruitment took 15 months. Twenty-six of 69 (37.7%) were not eligible due mainly to low CD4%. Twenty four and 19 were randomized to arms 1 and 2 respectively. All accepted the randomized arm; however, 3 in arm 1 stopped ART and 1 in arm 2 refused to start ART. Ten/19 (53%) in arm 2 started ART. At baseline, median age was 4.8 yrs, CDC A:B were 36:7, median CD4 was 19% and viral load was 4.8 log. All in arm 1 and 17/19 in arm 2 completed the study (median of 134 weeks). No one had AIDS or death. Four in immediate arm had tuberculosis. Once started on ART, deferred arm children achieved similar CD4 and viral load response as the immediate arm. Adverse events were similar between arms. The deferred arm had a 26% ART saving.

CONCLUSION

Almost 40% of children were not eligible due mainly to low CD4% but adherence to randomized treatment and retention in trial were excellent. A larger study to evaluate when to start ART is feasible.

Current and future antiretroviral treatment options in paediatric HIV infection

Because of a lack of prevention policies or problems in implementing prevention of mother-to-child transmission (P-MTCT), most of the 1500 daily new HIV infections in children aged<15 years are caused by MTCT. Fifteen percent of all HIV-infected individuals are children, but the vast majority lack access to highly active antiretroviral therapy (HAART), which can drastically reduce morbidity and mortality. There are 22 antiretroviral drugs currently approved by the US FDA for use in the treatment of HIV-infected adults and adolescents, but only 12 of these drugs are approved for use in children. Antiretroviral drugs belong to four major classes: nucleoside and nucleotide analogue reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors and fusion inhibitors. According to international guidelines developed by organizations including WHO, the Paediatric European Network for Treatment of AIDS (PENTA) and the US National Institutes of Health (US-NIH), the treatment of choice for HIV-infected children and adults is a combination of two NRTIs (backbone treatment) plus a third potent agent from a different class, either an NNRTI or a ritonavir-boosted protease inhibitor. There are specific challenges in treating HIV-infected children, including uncertainty about the best time to start treatment, the need for more paediatric formulations, the lack of pharmacokinetic studies for new drugs, and incomplete dosing guidelines. Furthermore, the most appropriate regimen for an individual child depends on a variety of factors, including the age of the child; the availability of appropriate drug formulations; the potency, complexity and toxicity of the drug regimen; the home situation; the child and caregiver's ability to adhere to the regimen; and the child's antiretroviral treatment history. In addition, antiretroviral drugs are not licensed for all age groups and the drugs are often not affordable. This review describes NNRTI and protease inhibitors as key components of first- and second-line antiretroviral therapy (ART), focusing on the rationale for choosing an NNRTI- versus protease inhibitor-based regimen based on the results of available phase II and III studies. Some of the new agents available for children as second-line and salvage therapy both on- and off-label are also discussed. The drug regimens described in this review are relevant to clinicians in developed and developing countries. The availability of new, potent compounds with different resistance and toxicity profiles may represent an alternative option to interclass switching and could redefine ART strategy, including the option of first-line NRTI-sparing regimens.

Total lymphocyte count: not a surrogate marker for risk of death in HIV-infected Ugandan children

OBJECTIVES

To determine the utility of total lymphocyte count (TLC) in predicting the 12-month mortality in HIV-infected Ugandan children and to correlate TLC and CD4 cell %.

DESIGN

This is a retrospective data analysis of clinical and laboratory data collected prospectively on 128 HIV-infected children in the HIV Network for Prevention Trials 012 trial.

METHODS

TLC and CD4 cell % measurements were obtained at birth, 14 weeks, and 12, 24, 36, 48, and 60 months of age and assessed with respect to risk of death within 12 months.

RESULTS

Median TLC per microliter (CD4 cell %) was 4150 (41%) at birth, 4900 (24%) at 12 months, 4300 (19%) at 24 months, 4150 (19%) at 36 months, 4100 (18%) at 48 months, and 3800 (20%) at 60 months. The highest risk of mortality within 12 months was 34% - 37% at birth and declined to 13%-15% at 24 months regardless of TLC measurement. The correlation between CD4 cell % and TLC was extremely low overall (r = 0.01).

CONCLUSIONS

The TLC did not predict a risk of progression to death within 12 months in HIV-infected Ugandan children. Therefore, TLC alone may not be a useful surrogate marker for determining those children at highest risk of death, who require antiretroviral therapy most urgently.

CD4 cell response before and after HAART initiation according to viral load and growth indicators in HIV-1-infected children in Abidjan, Côte d'Ivoire

OBJECTIVE

To analyze the determinants of CD4 change in children during 3 periods: before highly active antiretroviral therapy (HAART), during the first year after HAART initiation, and past 1 year after HAART initiation.

METHODS

One hundred seventy-seven children enrolled in a prospective cohort in Abidjan received HAART during a mean follow-up of 30 months. A linear mixed-effects model was used for the first period, a mixed-effects piecewise model for the second period, and an asymptotic mixed-effects model for long-term CD4 dynamics.

RESULTS

Before HAART initiation, CD4 percentage decreased along time [beta = -0.59 (-0.92 to -0.26)] was positively associated with body mass index for age [beta = 0.47 (0.22 to 0.72)] and negatively associated with viral load [beta = -1.01 (-1.90 to -0.13)]. During the first year of treatment, the CD4 decrease reverted to a steep increase that was negatively associated with age at HAART initiation [beta = -0.24 (-0.4 to -0.07)] and with the mean viral load under HAART [beta = -1.51 (-2.21 to -0.81)]. The long-term CD4 percentage was also negatively associated with the mean viral load under HAART [beta = -4.97 (-6.22 to -3.72)] and age at HAART initiation [beta = -0.82 (-1.12 to -0.51)].

CONCLUSIONS

Before HAART initiation, the CD4 cell percentage was associated with growth indicators whereas, after HAART, an early increase and a long-term plateau were negatively associated with the viral load and age at HAART initiation.

Response to combination antiretroviral therapy: variation by age

OBJECTIVE

To provide information on responses to combination antiretroviral therapy in children, adolescents and older HIV-infected persons.

DESIGN AND SETTING

Multicohort collaboration of 33 European cohorts.

SUBJECTS

: Forty-nine thousand nine hundred and twenty-one antiretroviral-naive individuals starting combination antiretroviral therapy from 1998 to 2006.

OUTCOME MEASURES

Time from combination antiretroviral therapy initiation to HIV RNA less than 50 copies/ml (virological response), CD4 increase of more than 100 cells/microl (immunological response) and new AIDS/death were analysed using survival methods. Ten age strata were chosen: less than 2, 2-5, 6-12, 13-17, 18-29, 30-39 (reference group), 40-49, 50-54, 55-59 and 60 years or older; those aged 6 years or more were included in multivariable analyses.

RESULTS

The four youngest age groups had 223, 184, 219 and 201 individuals and the three oldest age groups had 2693, 1656 and 1613 individuals. Precombination antiretroviral therapy CD4 cell counts were highest in young children and declined with age. By 12 months, 53.7% (95% confidence interval: 53.2-54.1%) and 59.2% (58.7-59.6%) had experienced a virological and immunological response. The probability of virological response was lower in those aged 6-12 (adjusted hazard ratio: 0.87) and 13-17 (0.78) years, but was higher in those aged 50-54 (1.24), 55-59 (1.24) and at least 60 (1.18) years. The probability of immunological response was higher in children and younger adults and reduced in those 60 years or older. Those aged 55-59 and 60 years or older had poorer clinical outcomes after adjusting for the latest CD4 cell count.

CONCLUSION

Better virological responses but poorer immunological responses in older individuals, together with low precombination antiretroviral therapy CD4 cell counts, may place this group at increased clinical risk. The poorer virological responses in children may increase the likelihood of emergence of resistance.

Pediatric HIV infection: the state of antiretroviral therapy

Pediatric HIV/AIDS has become less of a problem in resource-rich countries as the number of perinatal infections has reduced dramatically since the advent of antiretrovirals, resulting in the effective prevention of mother-to-child transmission. In resource-limited settings, however, pediatric HIV infection remains a colossal problem; a separate review in this same issue of Expert Review of Anti-Infective Therapy examines the international aspects of pediatric HIV/AIDS. Treatment of HIV infection in children differs from that in adults in the use of immunologic markers and owing to drug pharmacokinetics and age-related adherence issues. This review, geared for the general pediatrician or family practitioner who may see the HIV-positive child in the clinic or the hospital, summarizes the most recent pediatric data and guidelines for the testing and treatment of HIV, including the US NIH guidelines released in February 2008. Treatment-experienced patients, who should be cared for by pediatric HIV specialists, are not addressed here specifically. Adolescents, infected either perinatally or sexually, with their own unique issues, deserve a separate review.

Delayed early antiretroviral treatment is associated with an HIV-specific long-term cellular response in HIV-1 vertically infected infants

Antiviral T-cell immune responses appear to be crucial to control HIV replication. Infants treated before the third month of life with highly active antiretroviral treatment (HAART) did not develop a persistent HIV-specific immune response. We evaluated how delayed initiation of HAART after 3 months of age influences the development of HIV-1-specific T-cell responses during long-term follow-up in 9 HIV-1 vertically infected infants. These data suggest that a longer antigenic stimulation, due to a larger window for therapeutic intervention with HAART, is associated with the establishment of a persistent specific HIV immune response resulting in a long-term viral control of vertically infected infants.