HIV Paediatric Prognostic Markers Collaborative Study. Use of total lymphocyte count for informing when to start antiretroviral therapy in HIV-infected children: a meta-analysis of longitudinal data

Effect of high-calorie formula on weight, height increment, IGF-1 and TLC in growth faltering children: A quasi-experimental study

High-calorie formulas have been used to promote catch-up growth in undernourished children. The level of insulin-like growth factor 1 (IGF-1) is closely related to weight and nutritional intake, whereas low a total lymphocyte count (TLC) is associated with impaired immune system function in undernourished children. This study was conducted to investigate the effect of high-calorie formula as an intervention on weight, height increment, IGF-1 and TLC in children with growth faltering or undernutrition. A quasi-experimental study with pre- and post-design was conducted in the outpatient clinic of a private hospital during October 2021-July 2022 on children with growth failure and underlying infection. For 90 days, subjects were given a high-calorie formula. An enzyme-linked immunosorbent assay was then conducted to measure IGF-1, followed by a complete blood count examination. Subjects were divided into two groups based on age: Group 1 (12-24 months) and Group 2 (>24-60 months). There was a significant increment in body weight and body length/height after intervention but no significant difference between the groups. The increment of body length/height after intervention was greater in Group 1 than Group 2 (p = 0.000) and reduced the incidence of stunted/severely stunted and wasted/severely wasted children (p > 0.05). IGF-1 increased after the intervention but with no significant difference (1.42 ± 8.31 ng/ml; p = 0.144). There was a significant reduction in TLC after the intervention (1194.34 + 4400.34 cells/mm3; p = 0.002) that was reduced in Group 1 and slightly increased in Group 2 (p = 0.003). Being underweight/severely underweight increased the risk of a low TLC by 27.658-fold but this risk was reduced by 25.904-fold after nutritional intervention. High-calorie formula intervention increases body weight and body length/height, reduces the incidence of underweight, stunted and wasted children and improves IGF-1 levels.

Association between pretreatment lymphocyte count and efficacy of immune-enhancing therapy in acute necrotising pancreatitis: a post-hoc analysis of the multicentre, randomised, placebo-controlled TRACE trial

Background

Immune-enhancing thymosin alpha 1 (Tα1) therapy may reduce infected pancreatic necrosis (IPN) in acute necrotising pancreatitis (ANP). However, the efficacy might be impacted by lymphocyte count due to the pharmacological action of Tα1. In this post-hoc analysis, we tested the hypothesis that pre-treatment absolute lymphocyte count (ALC) determines whether patients with ANP benefit from Tα1 therapy.

Methods

A post-hoc analysis of data from a multicentre, double-blind, randomised, placebo-controlled trial testing the efficacy of Tα1 therapy in patients with predicted severe ANP was performed. Patients from 16 hospitals of China were randomised to receive a subcutaneous injection of Tα1 1.6 mg every 12 h for the frst 7 days and 1.6 mg once a day for the following 7 days or a matching placebo during the same period. Patients who discontinued the Tα1 regimen prematurely were excluded. Three subgroup analyses were conducted using the baseline ALC (at randomisation), and the group allocation was maintained as intention-to-treat. The primary outcome was the incidence of IPN 90 days after randomisation. The fitted logistic regression model was applied to identify the range of baseline ALC where Tα1 therapy could exert a maximum effect. The original trial is registered with ClinicalTrials.gov, NCT02473406.

Findings

Between March 18, 2017, and December 10, 2020, a total of 508 patients were randomised in the original trial, and 502 were involved in this analysis, with 248 in the Tα1 group and 254 in the placebo group. Across the three subgroups, there was a uniform trend toward more significant treatment effects in patients with higher baseline ALC. Within the subgroup of patients with baseline ALC≥0.8 × 10ˆ9/L (n = 290), the Tα1 therapy significantly reduced the risk of IPN (covariate adjusted risk difference, -0.12; 95% CI, -0.21,-0.02; p = 0.015). Patients with baseline ALC between 0.79 and 2.00 × 10ˆ9/L benefited most from the Tα1 therapy in reducing IPN (n = 263).

Interpretation

This post-hoc analysis found that the efficacy of immune-enhancing Tα1 therapy on the incidence of IPN may be associated with pretreatment lymphocyte count in patients with acute necrotising pancreatitis.

Funding

National Natural Science Foundation of China.

Trajectories of Lymphocyte Counts in the Early Phase of Acute Pancreatitis Are Associated With Infected Pancreatic Necrosis

INTRODUCTION

Infected pancreatic necrosis (IPN) is an important complication of acute pancreatitis (AP). Absolute lymphocyte count (ALC) was reported to be associated with immunosuppression and the development of IPN. The aim of this study was to describe the trajectory of ALC during the early phase of AP and assess its association with IPN.

METHODS

We retrospectively screened patients with AP admitted to our center between January 2016 and July 2019. The ALC levels for the first 7 days after admission were collected. Group-based trajectory modeling was performed to detect the trajectories. Cox proportional hazards regression model was adopted to identify potential risk factors of IPN.

RESULTS

Overall, 292 patients were enrolled for analysis. A triple-group trajectory model was developed, assigning 116 patients to the low-level ALC group, 133 to the medium-level ALC group, and 43 to the high-level ALC group. There was no overall significant difference regarding the incidence of IPN among the 3 groups (P = 0.066). In pairwise comparison, patients in the low-level ALC group had significantly higher incidence of IPN than those in the high-level ALC group (hazard ratio: 3.50; 95% confidence interval: 1.22-10.00, P = 0.020). Length of hospital stay and intensive care unit stay differed significantly among patients with different trajectories (P = 0.042 and 0.033, respectively).

DISCUSSION

Despite the fact that the trajectories of ALC is overall insignificant for the development of IPN, patients with persistent low ALC trajectories during the early phase of AP are more likely to develop IPN when compared with patients with high ALC trajectories.

Common and Novel Markers for Measuring Inflammation and Oxidative Stress Ex Vivo in Research and Clinical Practice-Which to Use Regarding Disease Outcomes?

Many chronic conditions such as cancer, chronic obstructive pulmonary disease, type-2 diabetes, obesity, peripheral/coronary artery disease and auto-immune diseases are associated with low-grade inflammation. Closely related to inflammation is oxidative stress (OS), which can be either causal or secondary to inflammation. While a low level of OS is physiological, chronically increased OS is deleterious. Therefore, valid biomarkers of these signalling pathways may enable detection and following progression of OS/inflammation as well as to evaluate treatment efficacy. Such biomarkers should be stable and obtainable through non-invasive methods and their determination should be affordable and easy. The most frequently used inflammatory markers include acute-phase proteins, essentially CRP, serum amyloid A, fibrinogen and procalcitonin, and cytokines, predominantly TNFα, interleukins 1β, 6, 8, 10 and 12 and their receptors and IFNγ. Some cytokines appear to be disease-specific. Conversely, OS-being ubiquitous-and its biomarkers appear less disease or tissue-specific. These include lipid peroxidation products, e.g., F2-isoprostanes and malondialdehyde, DNA breakdown products (e.g., 8-OH-dG), protein adducts (e.g., carbonylated proteins), or antioxidant status. More novel markers include also -omics related ones, as well as non-invasive, questionnaire-based measures, such as the dietary inflammatory-index (DII), but their link to biological responses may be variable. Nevertheless, many of these markers have been clearly related to a number of diseases. However, their use in clinical practice is often limited, due to lacking analytical or clinical validation, or technical challenges. In this review, we strive to highlight frequently employed and useful markers of inflammation-related OS, including novel promising markers.

An Evaluation of Alternative Markers to Guide Initiation of Anti-retroviral Therapy in HIV-Infected Children in Settings where CD4 Assays are not Available

OBJECTIVES

In settings where CD4 testing is not available, alternative markers to start paediatric anti-retroviral therapy (ART) could be used. A comprehensive evaluation of these markers has not been performed.

METHODS

Prospective cross-sectional study of HIV-infected Malawian children not eligible for ART based on clinical criteria. Associations between CD4 and alternative markers [haemoglobin, total lymphocyte count (TLC), serum albumin, thrombocytes and growth parameters] were analysed, and accuracy of existing and new cut-offs were evaluated.

RESULTS

In all, 417 children were enrolled. Of 261 children aged ≥5 years, 155 (59%) qualified to start ART using CD4. In this group, only TLC was associated with CD4 (p < 0.001). Sensitivity for TLC was 21% (95% CI: 15-29%), using World Health Organization cut-offs. Improved cut-offs increased sensitivity to 73% (95% CI: 65-80%), specificity 62% (95% CI: 52-72%).

CONCLUSION

Clinical staging alone is an unreliable strategy to start ART in children. TLC is the only alternative marker for CD4, cut-offs need to be revised though.

Paediatric European Network for Treatment of AIDS (PENTA) guidelines for treatment of paediatric HIV-1 infection 2015: optimizing health in preparation for adult life

The 2015 Paediatric European Network for Treatment of AIDS (PENTA) guidelines provide practical recommendations on the management of HIV‐1 infection in children in Europe and are an update to those published in 2009. Aims of treatment have progressed significantly over the last decade, moving far beyond limitation of short‐term morbidity and mortality to optimizing health status for adult life and minimizing the impact of chronic HIV infection on immune system development and health in general. Additionally, there is a greater need for increased awareness and minimization of long‐term drug toxicity. The main updates to the previous guidelines include: an increase in the number of indications for antiretroviral therapy (ART) at all ages (higher CD4 thresholds for consideration of ART initiation and additional clinical indications), revised guidance on first‐ and second‐line ART recommendations, including more recently available drug classes, expanded guidance on management of coinfections (including tuberculosis, hepatitis B and hepatitis C) and additional emphasis on the needs of adolescents as they approach transition to adult services. There is a new section on the current ART ‘pipeline’ of drug development, a comprehensive summary table of currently recommended ART with dosing recommendations. Differences between PENTA and current US and World Health Organization guidelines are highlighted and explained.

A sheath-less combined optical and impedance micro-cytometer

We describe a sheath-less micro-cytometer that measures four different parameters, namely fluorescence, large angle side scatter and dual frequency electrical impedance (electrical volume and opacity). The cytometer was benchmarked using both size and fluorescent bead standards and demonstrates excellent size accuracy (CVs ≤ 2.1%), sensitivity and dynamic range (3.5 orders of magnitude) at sample flow rates of 80 μL per minute. The cytometer was evaluated by analysing human blood, and a four part differential leukocyte assay for accurate CD4+ T-cell enumeration was demonstrated. The integration of impedance, fluorescence and side scatter into a single miniature cytometer platform provides the core information content of a classical cytometer in a highly compact, simple, portable and low cost format.

Incidence of World Health Organization stage 3 and 4 events, tuberculosis and mortality in untreated, HIV-infected children enrolling in care before 1 year of age: an IeDEA (International Epidemiologic Databases To Evaluate AIDS) East Africa regional analysis

BACKGROUND

Few studies have reported CD4%- and age-stratified rates of World Health Organization Stage 3 (WHO3) events, World Health Organization Stage 4 (WHO4) events, tuberculosis (TB) and mortality in HIV-infected infants before initiation of antiretroviral therapy.

METHODS

HIV-infected children enrolled before 1 year of age in the International Epidemiologic Databases to Evaluate AIDS East Africa region (October 1, 2002, to November, 2008) were included. We estimated incidence rates of earliest clinical event (WHO3, WHO4 and TB), before antiretroviral therapy initiation per local guidelines, stratified by current age (< or ≥6 months) and current CD4% (<15%, 15-24%, ≥25%). CD4%-stratified mortality rates were estimated separately for children who did not experience a clinical event ("background" mortality) and for children who experienced an event, including "acute" mortality (≤30 days post event) and "later" mortality (>30 days post event).

RESULTS

Among 847 children (median enrollment age: 4.8 months; median pre-antiretroviral therapy follow up: 10.8 months; 603 (71%) with ≥1 CD4% recorded), event rates were comparable for those aged <6 and ≥6 months. Current CD4% was associated with risk of WHO4 events for children <6 months of age and with all evaluated events for children ≥6 months old (P < 0.05). "Background" mortality was 3.7-8.4/100 person-years (PY). "Acute" mortality (≤30 days post event) was 33.8/100 PY (after TB) and 41.1/100 PY (after WHO3 or WHO4). "Later" mortality (>30 days post event) ranged by CD4% from 4.7 to 29.1/100 PY.

CONCLUSIONS

In treatment-naïve, HIV-infected infants, WHO3, WHO4 and TB events were common before and after 6 months of age and led to substantial increases in mortality. Early infant HIV diagnosis and treatment are critically important, regardless of CD4%.

Total lymphocyte count as a surrogate marker to predict CD4 count in human immunodeficiency virus-infected children: a retrospective evaluation

A retrospective study was conducted, and 576 human immunodeficiency virus-infected children with total lymphocyte count (TLC) and CD4 count were recruited from China. Spearman rank order correlation and receiver-operating characteristic were used. An overall positive correlation was noted between TLC and CD4 count (prehighly active antiretroviral therapy [pre-HAART], r = 0.789, 6 months of HAART, r = 0.642, 12 months of HAART, r = 0.691, P = 0.001). TLC ≤ 2600 cells/mm(3) predicted a CD4 count of ≤ 350 cells/mm(3) with 82.9% sensitivity, 79.6% specificity pre-HAART. Meanwhile, the optimum prediction for CD4 count of ≤ 350 cells/mm(3) was a TLC of ≤ 2400 cells/mm at 6 months (73.6% sensitivity and 74.1% specificity) and 12 months (81.7% sensitivity and 76.5% specificity) of HAART. TLC can be used as a surrogate marker for predicting CD4 count of human immunodeficiency virus-infected children before and during HAART in resource-limited countries.

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.

Monitoring Antiretroviral Therapy in HIV-Infected Children in Resource-Limited Countries: A Tale of Two Epidemics

Twenty-nine years into the HIV epidemic, several advances have been made; however, there remain several challenges particularly with pediatric HIV in resource-limited countries. The obstacles facing pediatric antiretroviral therapy (ART) delivery in resource-limited countries are multifaceted: lack of health care infrastructure, limited availability of pediatric drug formulations, lack of early HIV diagnostic and monitoring techniques, limited manpower with expertise in pediatric HIV care, limited donor funding, and competing public health priorities with limited health care budget. In this paper, the challenges with various ART monitoring tools in resource-limited countries are discussed. Noninvasive (e.g., patient, clinical events outcome, and adherence) and invasive (e.g., immunologic and virologic) monitoring tools are discussed. Several cheap and technically less complex laboratory tests for monitoring are becoming available. Funding agencies and country programs should invest in validating the use of current technologies to optimize pediatric HIV care in resource-limited countries.

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.

T-lymphocyte subsets in apparently healthy nigerian children

Population studies showed that there are differences in T-lymphocytes subpopulation of normal children in different regions, and reference values in an area might be different from another. This study compared the values in our population with CDC and WHO reference values. Blood samples from 279 healthy, HIV-negative children <12 years of age were analysed for complete blood count, CD3+, CD4+, CD8+ counts and percentages. Except for CD8%, mean values for all parameters measured significantly decreased with age. CD4+ counts were higher in females than males, P < .05. Using the WHO criteria, 15.9% of subjects had low total lymphocyte count and 20.6% had low CD4 count. Children <3 years had median CD4% lower than WHO normal values. Our median CD4+ counts correlated with CDC values. Values used by WHO in infants are higher than ours. We suggest that our children be assessed using CDC reference values which correlate with ours.

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.

Comparison of previous and present World Health Organization clinical staging criteria in HIV-infected Malawian children

In many settings, HIV infected children are looked after with limited access to CD4 cell count or viral load. The decision to initiate antiretroviral therapy (ART) is made clinically, based on the WHO paediatric staging criteria, which were revised in 2006. Results of using new and old criteria were compared. Of 694 children, 626 (90.2%) fulfilled criteria to start ART when applying the new WHO staging guidelines, whereas 330 (47.6%) children were eligible for ART when using the old WHO criteria. This signifies a marked rise in the number of paediatric patients qualifying for ART on clinical grounds.

Predictors for mortality and loss to follow-up among children receiving anti-retroviral therapy in Lilongwe, Malawi

OBJECTIVES

To determine predictors of mortality in children on anti-retroviral therapy (ART) who attended the Paediatric HIV Clinic at Kamuzu Central Hospital in Lilongwe, Malawi.

METHODS

Retrospective case cohort study by chart review of children who had started ART between October 2004 and May 2006. Bivariable and multivariable analysis were performed with and without defaulters to evaluate associations according to vital status and to identify independent predictors of mortality.

RESULTS

Forty-one of 258 children (15.9%) were deceased, 185 (71.7%) were alive, and 32 (12.4%) had defaulted: 51% were female, 7% were under 18 months, 26% were 18 months to 5 years, and 54% were >5 years of age. Most were WHO stage III or IV (56% and 37%, respectively). On multivariate analysis, factors most strongly associated with mortality and defaulting were age <18 months [hazards ratio (HR) 2.11 (95% CI 1.0-4.51)] and WHO stage IV [HR 2.00 (95% CI 1.07-3.76)].

CONCLUSIONS

To improve outcomes of HIV-positive children, they must be identified and treated early, specifically children under 18 months of age. Access to infant diagnostic procedures must be improved to allow effective initiation of ART in infants at higher risk of death.

Total lymphocyte count and World Health Organization pediatric clinical stage as markers to assess need to initiate antiretroviral therapy among human immunodeficiency virus-infected children in Moshi, Northern Tanzania

BACKGROUND

The World Health Organization (WHO) has recommended the use of clinical staging alone and with total lymphocyte count to identify HIV infected children in need of antiretroviral therapy (ART) in resource-limited settings, when CD4 cell count is not available.

METHODS

We prospectively enrolled children obtaining care for HIV infection at the Kilimanjaro Christian Medical Centre Pediatric Infectious Diseases Clinic in Moshi, Tanzania between March 2004 and May 2006 for this cohort study.

RESULTS

One hundred ninety two (89.7%) of 214 children met WHO ART initiation criteria based on clinical staging or CD4 cell count. Several low-cost measures identified individuals who met WHO ART initiation criteria to the following degree: WHO stages 3 or 4 had 87.5% (95% CI, 82.8-92.1) sensitivity and, by definition, 100% (CI, 100-100) specificity; WHO recommended advance disease TLC cutoffs: sensitivity = 23.9% (95% CI, 17.3-30.5) specificity = 78.2% (95% CI, 67.3-89.1). Low TLC was a common finding, (50 of 214; 23%); however, it did not improve the sensitivity or specificity of clinical staging in identifying the severely immunosuppressed stage 2 children. Growth failure or use of total lymphocyte counts in isolation were not reliable indicators of severe immunosuppression or need to initiate ART.

CONCLUSION

The use of total lymphocyte count does not improve the ability to identify children in need of ART compared with clinical staging alone. Low absolute lymphocyte count did not correlate with severe immunosuppression based on CD4 cell count in this cohort.

Validation of 2006 WHO prediction scores for true HIV infection in children less than 18 months with a positive serological HIV test

Introduction

All infants born to HIV-positive mothers have maternal HIV antibodies, sometimes persistent for 18 months. When Polymerase Chain Reaction (PCR) is not available, August 2006 World Health Organization (WHO) recommendations suggest that clinical criteria may be used for starting antiretroviral treatment (ART) in HIV seropositive children <18 months. Predictors are at least two out of sepsis, severe pneumonia and thrush, or any stage 4 defining clinical finding according to the WHO staging system.

Methods and Results

From January 2005 to October 2006, we conducted a prospective study on 236 hospitalized children <18 months old with a positive HIV serological test at the national reference hospital in Kigali. The following data were collected: PCR, clinical signs and CD4 cell count.

Current proposed clinical criteria were present in 148 of 236 children (62.7%) and in 95 of 124 infected children, resulting in 76.6% sensitivity and 52.7% specificity. For 87 children (59.0%), clinical diagnosis was made based on severe unexplained malnutrition (stage 4 clinical WHO classification), of whom only 44 (50.5%) were PCR positive. Low CD4 count had a sensitivity of 55.6% and a specificity of 78.5%.

Conclusion

As PCR is not yet widely available, clinical diagnosis is often necessary, but these criteria have poor specificity and therefore have limited use for HIV diagnosis. Unexplained malnutrition is not clearly enough defined in WHO recommendations. Extra pulmonary tuberculosis (TB), almost impossible to prove in young children, may often be the cause of malnutrition, especially in HIV-affected families more often exposed to TB. Food supplementation and TB treatment should be initiated before starting ART in children who are staged based only on severe malnutrition.

Clinical practice treatment of HIV infection in children

Perinatal transmission remains the main cause of HIV infection in the pediatric population. Treatment of HIV-infected children has become less of a problem in resource-rich countries with a remarkable decrease of perinatal infections, resulting in an effective prevention of mother-to-child transmission and antiretroviral treatment of HIV infection in pediatrics because of differences in drug pharmacokinetics, the lack of available licensed drugs, the use of different immunologic markers and age-related adherence issues. This review, for the general pediatrician, summarizes the most recent pediatric data and guidelines for treatment of HIV. Recommendations for when to initiate therapy are more aggressive in children than in adults, particularly in infants because disease progression in children is more rapid. The indications to start therapy differ by age and are based on international immunologic and clinical classification system for HIV infection. At present, combination regimens of at least three drugs are recommended. Moreover, therapies must also consider the potential complications in these children currently treated for a long time.

Measurement of CD4+ T cells in point-of-care settings with the Sysmex pocH-100i haematological analyser

The decision to provide antiretroviral therapy to HIV-positive patients mainly depends on the CD4(+) T-cell count, with therapy indicated at a cut-off value of <350-200 CD4(+) T cells/microl blood. Monitoring patients is still a major problem in countries with limited resources where blood samples often have to be transported over long distances to regional referral centres in which the count can be performed on flow cytometers. We have evaluated a newly developed simple and inexpensive method for CD4(+) T-cell quantification. It is a variation of the Invitrogen T4 Quant kit, with manual isolation of nuclei from CD4(+) T cells and subsequent counting on the small haematology analyser pocH-100i, Sysmex. We have demonstrated that this new method is highly reproducible and gives stable and linear results over a wide range of CD4(+) T-cell concentrations. Method comparison to two different flow cytometers showed excellent correlation with concordances of about 93%. Overall, this method is rapid, easy to perform and offers a good reliable alternative to measurement by flow cytometry. The pocH-100i has the additional benefit of providing a complete blood count with a three-part white blood cell differential and software for patient data storage and handling.

Early initiation of lopinavir/ritonavir in infants less than 6 weeks of age: pharmacokinetics and 24-week safety and efficacy

BACKGROUND

With increasing recognition of the benefits of early antiretroviral therapy initiation in perinatally HIV-infected infants, data are needed regarding the pharmacokinetics (PK), safety, and efficacy of recommended first-line protease inhibitors such as lopinavir/ritonavir (LPV/r).

METHODS

A prospective, phase I/II, open-label, dose-finding trial evaluated LPV/r at a dose of 300/75 mg/m twice daily plus 2 nucleoside analogs in HIV-1-infected infants > or =14 days to <6 weeks of age. Intensive 12-hour PK evaluations were performed after 2 weeks of LPV/r therapy, and doses were modified to maintain LPV predose concentrations >1 microg/mL and area under the curve (AUC) <170 microg hr/mL.

RESULTS

Ten infants enrolled [median age 5.7 (range, 3.6-5.9) weeks] with median HIV-1 RNA of 6.0 (range, 4.7-7.2) log10 copies/mL; all completed 24 weeks of follow-up. Nine completed the intensive PK evaluation at a median LPV dose of 267 (range, 246-305) mg/m q12 hours; median measures were AUC = 36.6 (range, 27.9-62.6) microg hr/mL; predose concentration = 2.2 (range, 0.99-4.9) microg/mL; maximum concentration = 4.76 (range, 2.84-7.28) microg/mL and apparent clearance (L/h/m) = 6.75 (range, 2.79-12.83). Adverse events were limited to transient grade 3 neutropenia in 3 subjects. By week 24, 2 of 10 subjects had experienced a protocol-defined virologic failure.

CONCLUSIONS

Although the LPV AUC in this population was significantly lower than that observed in infants ages 6 weeks to 6 months, LPV/r-based antiretroviral therapy in doses of 300/75 mg/m BID was well tolerated and resulted in virologic control in 8 of 10 infants by 24 weeks. Additional investigation is needed to understand the long-term implications of the lower LPV exposure in this age group.

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.

Absolute CD4+ T-lymphocyte count as a surrogate marker of pediatric human immunodeficiency virus disease progression

BACKGROUND

Traditionally in pediatric HIV, the CD4+ T-lymphocyte percent is used to monitor disease progression because of the variability in absolute CD4+ T-lymphocyte numbers. Because of the high cost of equipment, sophisticated and delicate technology, most laboratories in resource-limited settings use simple protocols that enumerate only the absolute CD4+ T-lymphocyte counts. We assessed the use of absolute CD4+ T-lymphocyte count as a surrogate marker of pediatric HIV disease progression.

METHODS

We analyzed the CD4+ T-lymphocytes and HIV viral load over a 10-year period (1996-2006) of 97 HIV-infected children enrolled in the Yale Prospective Longitudinal Pediatric HIV Cohort using generalized linear mixed models. Both CD4+ T-lymphocytes and HIV viral load were assessed at baseline and every 2-3 months. The modeling approach used in this study allows the intercept and the rate at which outcome variables change over time to vary across participants.

RESULTS

We determined that absolute CD4+ T-lymphocytes count was just as reliable at monitoring pediatric HIV as CD4+ T-lymphocyte percentage. Antiretroviral treatment, regardless of the regimen used, was associated with higher CD+ T-lymphocytes count (P < 0.01). Race was significantly associated with CD4+ T-lymphocytes counts (with lower values for blacks compared with nonblacks; P < 0.01). The presence of other infections was associated with lower CD4+ T-lymphocyte count (P = 0.01) and higher viral load (P < 0.01), respectively.

CONCLUSIONS

In situations where determination of CD4+ T-lymphocyte percentages is not readily available, the absolute count may provide an affordable and accessible laboratory surrogate marker of HIV disease progression in children.

Computed CD4 percentage as a low-cost method for determining pediatric antiretroviral treatment eligibility

Background

The performance of the WHO recommendations for pediatric antiretroviral treatment (ART) in resource poor settings is insufficiently documented in routine care.

Methods

We compared clinical and immunological criteria in 366 children aged 0 to 12 years in Kinshasa and evaluated a simple computation to estimate CD4 percent, based on CD4 count, total white blood cell count and percentage lymphocytes. Kappa (κ) statistic was used to evaluate eligibility criteria and linear regression to determine trends of CD4 percent, count and total lymphocyte count (TLC).

Results

Agreement between clinical and immunological eligibility criteria was poor (κ = 0.26). One third of children clinically eligible for ART were ineligible using immunological criteria; one third of children immunologically eligible were ineligible using clinical criteria. Among children presenting in WHO stage I or II, 54 (32%) were eligible according to immunological criteria. Agreement with CD4 percent was poor for TLC (κ = 0.04), fair for total CD4 count (κ = 0.39) and substantial for CD4 percent computational estimate (κ = 0.71). Among 5 to 12 years old children, total CD4 count was higher in younger age groups (-32 cells/mm³ per year older), CD4 percent was similar across age groups.

Conclusion

Age-specific thresholds for CD4 percent optimally determine pediatric ART eligibility. The use of CD4 percent computational estimate may increase ART access in settings with limited access to CD4 percent assays.

Change over time of mortality predictors after HAART initiation in a Senegalese cohort

BACKGROUND

In 1998, Senegal was among the first sub-Saharan African countries to launch a Highly active anti-retroviral therapy (HAART) access program. Initial studies have demonstrated the feasibility and efficacy of this initiative. Analyses showed a peak of mortality short after starting HAART warranting an investigation of early and late mortality predictors.

METHODS

404 HIV-1-infected Senegalese adult patients were enrolled and data censored as of September 2005. Predictor effects on mortality were first examined over the whole follow-up period (median 46 months) using a Cox model and Shoenfeld residuals. Then, changes of these effects were examined separately over the early and late treatment periods; i.e., less and more than 6-month follow-up.

RESULTS

During the early period, baseline body mass index and baseline total lymphocyte count were significant predictors of mortality (Hazard Ratios 0.82 [0.72-0.93] and 0.80 [0.69-0.92] per 200 cell/mm3, respectively) while baseline viral load was not significantly associated with mortality. During the late period, viro-immunological markers (baseline CD4-cell count and 6-month viral load) had the highest impact. In addition, the viral load at 6-month was a significant predictor (HR = 1.42 [1.20-1.66]).

CONCLUSION

In this cohort, impaired clinical status could explain the high early mortality rate while viro-immunological markers were rather predictors of late mortality.

Markers for predicting mortality in untreated HIV-infected children in resource-limited settings: a meta-analysis

OBJECTIVES

To evaluate the prognostic value of selected laboratory and growth markers on the short-term risk of mortality in untreated HIV-infected children in resource-limited settings.

DESIGN

A meta-analysis of individual longitudinal data on children aged 12 months onwards from 10 studies (nine African, one Brazilian in the 3Cs4kids collaboration).

METHODS

The risk of death within 12 months based on age and the most recent measurements of laboratory and growth markers was estimated using Poisson regression models, adjusted for cotrimoxazole prophylaxis use and study effects.

RESULTS

A total of 2510 children contributed 357 deaths during 3769 child-years-at-risk, with 81% follow-up occurring after start of cotrimoxazole. At first measurement, median age was 4.0 years (interquartile range, 2.2-7.0 years), median CD4% was 15% and weight-for-age z-score -1.9. CD4% and CD4 cell count were the strongest predictors of mortality, followed by weight-for-age and haemoglobin. After adjusting for these markers, the effects of total lymphocyte count and BMI-for-age were relatively small. Young children who were both severely malnourished and anaemic had high mortality regardless of CD4 values, particularly those aged 1-2 years. By contrast, high CD4% or CD4 cell count values predicted low mortality level amongst either children older than 5 years or those younger with neither severe malnutrition nor anaemia.

CONCLUSIONS

CD4 measurements are the most important indicator of mortality and wider access to affordable tests is needed in resource-limited settings. Evaluation of antiretroviral initiation in children also needs to consider weight-for-age and haemoglobin. Prevention and treatment of malnutrition and anaemia is integral to HIV paediatric care and could improve survival.

Early response to highly active antiretroviral therapy in HIV-1-infected Kenyan children

OBJECTIVES

To describe the early response to World Health Organization (WHO)-recommended nonnucleoside reverse transcriptase inhibitor (NNRTI)-based first-line highly active antiretroviral therapy (HAART) in HIV-1-infected Kenyan children unexposed to nevirapine.

DESIGN

Observational prospective cohort.

METHODS

HIV-1 RNA level, CD4 lymphocyte count, weight for age z score, and height for age z score were measured before the initiation of HAART and every 3 to 6 months thereafter. Children received no nutritional supplements.

RESULTS

Sixty-seven HIV-1-infected children were followed for a median of 9 months between August 2004 and November 2005. Forty-seven (70%) used zidovudine, lamivudine (3TC), and an NNRTI (nevirapine or efavirenz), whereas 25% used stavudine (d4T), 3TC, and an NNRTI. Nevirapine was used as the NNRTI by 46 (69%) children, and individual antiretroviral drug formulations were used by 63 (94%), with only 4 (6%) using a fixed-dose combination of d4T, 3TC, and nevirapine (Triomune; Cipla, Mumbai, India). In 52 children, the median height for age z score and weight for age z score rose from -2.54 to -2.17 (P<0.001) and from -2.30 to -1.67 (P=0.001), respectively, after 6 months of HAART. Hospitalization rates were significantly reduced after 6 months of HAART (17% vs. 58%; P<0.001). The median absolute CD4 count increased from 326 to 536 cells/microL (P<0.001), the median CD4 lymphocyte percentage rose from 5.8% before treatment to 15.4% (P<0.001), and the median viral load fell from 5.9 to 2.2 log10 copies/mL after 6 months of HAART (P<0.001). Among 43 infants, 47% and 67% achieved viral suppression to less than 100 copies/mL and 400 copies/mL, respectively, after 6 months of HAART.

CONCLUSION

Good early clinical and virologic response to NNRTI-based HAART was observed in HIV-1-infected Kenyan children with advanced HIV-1 disease.

Determinants of Survival Without Antiretroviral Therapy After Infancy in HIV-1-Infected Zambian Children in the CHAP Trial

BACKGROUND

There are few data on predictors of HIV progression in untreated children in resource-limited settings.

METHODS

Children with HIV Antibiotic Prophylaxis (CHAP) was a randomized trial comparing cotrimoxazole prophylaxis with placebo in HIV-infected Zambian children. The prognostic value of baseline characteristics was investigated using Cox models.

RESULTS

Five hundred fourteen children aged 1 to 14 (median 5.5) years contributed 607 years follow-up (maximum 2.6 years). Half were boys, and in 67%, the mother was the primary carer; at baseline, median CD4 percentage was 11% and weight was less than third percentile in 67%. One hundred sixty-five children died (27.2 per 100 years at risk; 95% confidence interval 23.3-31.6). Low weight-for-age, CD4 percentage, hemoglobin, mother as primary carer, current malnutrition, and previous hospital admissions for respiratory tract infections or recurrent severe bacterial infections were independent predictors of poorer survival, whereas oral candidiasis predicted poorer survival only when baseline CD4 percentage was not considered. Mortality rates per 100 child years of 44.5 (37.2-53.2), 14.7 (10.9-19.8), and 2.3 (0.3-16.7) were associated with new World Health Organization stages 4, 3, and 1/2, respectively, applied retrospectively; very low weight-for-age was the only staging feature for 42% of stage 4 children.

CONCLUSIONS

Malnutrition and hospitalizations for respiratory/bacterial infections predict mortality independent of immunosuppression, suggesting that they capture HIV- and non-HIV-related mortality, whereas oral candidiasis is a proxy for immunosuppression.

Predictive value of absolute CD4 cell count for disease progression in untreated HIV-1-infected children

OBJECTIVES

To describe the relationship between absolute CD4 cell count and the short-term risk of disease progression in HIV-1-infected children.

DESIGN

A meta-analysis of individual longitudinal data on HIV-1-infected children enrolled in trials and cohort studies in Europe and the USA.

METHODS

The risks of progression to death and AIDS (or death) within 12 months, in terms of age and the most recent CD4 cell count, were estimated using parametric survival models. The analysis was restricted to measurements before the start of antiretroviral therapy except zidovudine monotherapy. The values of the absolute CD4 cell count and percentage predicting selected levels of disease progression risk were determined from this and previous models.

RESULTS

A total of 566 deaths was observed over 9128 person-years of follow-up, and 992 children progressed to AIDS or death over 7309 person-years of follow-up. In children older than 4 or 5 years, the estimated risk of disease progression increased sharply when the CD4 cell count fell below 200-300 cells/microl. As with other immunological markers, CD4 cell count was less prognostic in younger children. The CD4 cell count values predicting a 12-month risk of death of 2-5% and of AIDS of 5-10% were much more strongly influenced by age than equivalent CD4 cell percentage values.

CONCLUSION

This study suggests it may be appropriate to extend CD4 cell count criteria for initiating antiretroviral therapy in HIV-1-infected adults to children as young as 4 or 5 years. Monitoring by CD4 cell count in younger children is problematical because age is a highly influential variable.