Effect of isoniazid prophylaxis on mortality and incidence of tuberculosis in children with HIV: randomised controlled trial

BCG Vaccination in HIV-Infected Children

Despite the use of Bacillus Calmette-Guérin (BCG) vaccination for many years, infants and young children exposed to adults with infectious forms of tuberculosis (TB) are at high risk of developing complicated TB disease. This risk is much higher among HIV-infected children, and data on BCG protective efficacy in HIV-infected children is lacking. Recent research on BCG safety in HIV-infected infants has resulted in policy shifts, but implementation is challenging. New approaches to preventing TB among infants and children, particularly HIV-infected infants, are needed. This paper briefly reviews BCG safety and efficacy considerations in HIV-infected infants and discusses other approaches to preventing TB, including new TB vaccines and vaccination strategies.

TB and HIV in children - advances in prevention and management

The human immunodeficiency virus (HIV) epidemic has had a major impact on the age and gender profile of adult tuberculosis (TB) patients, resulting in increased exposure of HIV-infected and uninfected children at a very young age. Young and/or HIV-infected children are extremely vulnerable to develop severe forms of TB following recent exposure and infection. There is an urgent need to implement safe and pragmatic strategies to prevent TB in children, especially in TB endemic areas where they suffer the greatest burden of disease. The management of TB in HIV-infected children poses multiple challenges, but recent advances in the implementation of prevention of mother to child transmission (PMTCT) strategies and HIV care of infants offer hope. These include HIV testing and access to PMTCT for all pregnant women, routine testing of all HIV exposed infants and rapid initiation of antiretroviral treatment irrespective of clinical or immunological disease staging. In addition, careful scrutiny for TB exposure should occur at every health care visit, with provision of isoniazid preventive therapy (IPT) following each documented exposure event. Knowing the HIV infection status of child TB suspects is essential to optimize case management. Although multiple difficulties remain, recent advances demonstrate that the management of children with TB and/or HIV can be vastly improved by well focused interventions using readily available resources.

Factors influencing uptake of HIV care and treatment among children in South Africa - a qualitative study of caregivers and clinic staff

Despite antiretroviral therapy rollout in South Africa, fewer children than expected are accessing HIV care services. Our objectives were to describe barriers and facilitators of uptake of HIV care among children. Our study involved six private-sector clinics which provide HIV care free-of-charge in and around Gauteng province, South Africa. In-depth interviews were conducted in July 2008 with 21 caregivers of HIV-infected children attending these clinics, 21 clinic staff members and three lead members of staff from affiliated care centres. Many children were only tested for HIV after being recurrently unwell. The main facility-related barriers reported were long queues, negative staff attitudes, missed testing opportunities at healthcare facilities and provider difficulties with paediatric counselling and venesection. Caregivers reported lack of money for transport, food and treatments for opportunistic infections, poor access to welfare grants and lack of coordination amongst multiple caregivers. Misperceptions about HIV, maternal guilt and fear of negative repercussions from disclosure were common. Reported facilitators included measures implemented by clinics to help with transport, support from family and day-care centres/orphanages, and seeing children's health improve on treatment. Participants felt that better public knowledge about HIV would facilitate uptake. Poverty and the implications of children's HIV infection for their families underlie many of these factors. Some staff-related and practical issues may be addressed by improved training and simple measures employed at clinics. However, changing caregiver attitudes may require interventions at both individual and societal levels. Healthcare providers should actively promote HIV testing and care-seeking for children.

Opportunities for chemoprophylaxis in children with culture-confirmed tuberculosis

BACKGROUND AND OBJECTIVES

Chemoprophylaxis is an effective strategy to prevent progression of tuberculosis (TB) in vulnerable children who have had contact with an infectious source of TB. However, many operational gaps prevent implementation of routine chemoprophylaxis in high-burden settings. The TB exposure status and disease spectrum in children diagnosed with culture-confirmed TB are described and missed opportunities for chemoprophylaxis are highlighted.

METHODS

All children <13 years of age diagnosed with culture-confirmed TB at a tertiary referral hospital between March 2003 and February 2007 were included. Clinical data were collected from retrospective review of files. TB was classified as pulmonary and extra-pulmonary; disseminated TB included miliary disease and TB meningitis.

RESULTS

During the study period, 614 children (327, 53·3% boys, median age 32 months) were diagnosed with culture-confirmed TB. Contact with an infectious adult source case was documented in 333 (54·2%), 237 (71·2%) of whom were <5 years of age, and 24 (7·2%) were HIV-infected and ≥5 years of age. Of those eligible for chemoprophylaxis, missed opportunities were identified in 156/221 (70·6%) children; 127 (81·4%) were <3 years of age, 39 (25%) had disseminated TB and 8 (5·1%) died. The TB source case was the mother or father in 74/156 (47·4%) children.

CONCLUSION

Opportunities for initiation of chemoprophylaxis in vulnerable children following TB exposure are often missed. Awareness should be increased among health-care workers and in the community at large regarding the importance of chemoprophylaxis in young and HIV-infected children. Health system strengthening is required to improve delivery of chemoprophylaxis to vulnerable children in close contact with newly diagnosed infectious TB cases.

Human immunodeficiency virus and tuberculosis coinfection in children: challenges in diagnosis and treatment

The burden of childhood tuberculosis (TB) is influenced by the human immunodeficiency virus (HIV) epidemic and this dangerous synergy affects various aspects of both diseases; from pathogenesis and the epidemiologic profile to clinical presentation, diagnosis, treatment, and prevention. HIV-infected infants and children are at increased risk of developing severe forms of TB. The TB diagnosis is complicated by diminished sensitivity and specificity of clinical features and diagnostic tools like the tuberculin skin test and chest x-ray. Although alternative ways of pulmonary sampling and the development of interferon-γ assays have shown to lead to some improvement of TB diagnosis in HIV-infected children, new diagnostic tools are urgently needed. Coadministration of anti-TB treatment and antiretroviral drugs induces severe complications, and this highlights the need to define optimal treatment regimens. Practical implementation of these regimens in TB control programs should be combined with isoniazid preventive therapy in TB-exposed HIV-infected children. The risk of severe complications after Bacille Calmette-Guérin vaccination of HIV-infected children emphasizes the need for new nonviable vaccines. This article reviews the current status of pediatric HIV-TB coinfection with specific emphasis on the diagnosis and treatment.

HIV-Associated Tuberculosis

The intersecting HIV and Tuberculosis epidemics in countries with a high disease burden of both infections pose many challenges and opportunities. For patients infected with HIV in high TB burden countries, the diagnosis of TB, ARV drug choices in treating HIV-TB coinfected patients, when to initiate ARV treatment in relation to TB treatment, managing immune reconstitution, minimising risk of getting infected with TB and/or managing recurrent TB, minimizing airborne transmission, and infection control are key issues. In addition, given the disproportionate burden of HIV in women in these settings, sexual reproductive health issues and particular high mortality rates associated with TB during pregnancy are important. The scaleup and resource allocation to access antiretroviral treatment in these high HIV and TB settings provide a unique opportunity to strengthen both services and impact positively in meeting Millennium Development Goal 6.

A randomized controlled trial of intermittent compared with daily cotrimoxazole preventive therapy in HIV-infected children

OBJECTIVE

Cotrimoxazole preventive therapy (CPT) reduces morbidity and mortality in HIV-infected children. The WHO recommends prolonged daily CPT for HIV-infected infants and children. In adults, intermittent CPT has been associated with less adverse events than daily, with increased tolerability and equal efficacy. We investigated the efficacy and tolerability of intermittent CPT compared with daily CPT in HIV-infected children over a 5-year period.

DESIGN

A prospective randomized controlled study.

METHODS

HIV-infected children aged at least 8 weeks were randomized to thrice weekly or daily CPT. Outcome measures were mortality, bacterial infections, hospitalizations and adverse events.

RESULTS

Three hundred and twenty-four children (median age 23 months) were followed for 672 child-years; 165 (51%) were randomized to intermittent CPT. Most children (287, 89%) were Centers for Disease Control and Prevention clinical category B or C; 207 (64%) received HAART during the study. Mortality (53 deaths, 16%) was similar in the intermittent CPT compared with the daily CPT group {24 (14%) vs. 29 (18%), hazard ratio 0.75 [95% confidence interval (CI) 0.44-1.29]}. The predominant causes of death in both groups were sepsis (17, 32%), pneumonia (13, 25%) or diarrhoea (8, 15%). Intermittent CPT was associated with more bacteraemias [incidence rate ratio 2.36 (95% CI 1.21-4.86)]. Children receiving intermittent CPT also spent more days in hospital [incidence rate ratio 1.15 (95% CI 1.04-1.28)]. The rate of serious adverse events was similar between groups [incidence rate ratio 1.07 (95% CI 0.58-2.02)].

CONCLUSION

Intermittent CPT was associated with more invasive bacterial disease than daily CPT, but survival was similar. Both regimens were well tolerated. On balance, daily CPT remains preferable to intermittent therapy for HIV-infected children.

Interpreting meta-analysis according to the adequacy of sample size. An example using isoniazid chemoprophylaxis for tuberculosis in purified protein derivative negative HIV-infected individuals

Objective:

To illustrate the utility of statistical monitoring boundaries in meta-analysis, and provide a framework in which meta-analysis can be interpreted according to the adequacy of sample size. To propose a simple method for determining how many patients need to be randomized in a future trial before a meta-analysis can be deemed conclusive.

Study design and setting:

Prospective meta-analysis of randomized clinical trials (RCTs) that evaluated the effectiveness of isoniazid chemoprophylaxis versus placebo for preventing the incidence of tuberculosis disease among human immunodeficiency virus (HIV)-positive individuals testing purified protein derivative negative. Assessment of meta-analysis precision using trial sequential analysis (TSA) with LanDeMets monitoring boundaries. Sample size determination for a future trials to make the meta-analysis conclusive according to the thresholds set by the monitoring boundaries.

Results:

The meta-analysis included nine trials comprising 2,911 trial participants and yielded a relative risk of 0.74 (95% CI, 0.53–1.04, P = 0.082, I² = 0%). To deem the meta-analysis conclusive according to the thresholds set by the monitoring boundaries, a future RCT would need to randomize 3,800 participants.

Conclusion:

Statistical monitoring boundaries provide a framework for interpreting meta-analysis according to the adequacy of sample size and project the required sample size for a future RCT to make a meta-analysis conclusive.

The use of anti-tuberculosis therapy for latent TB infection

Tuberculosis infection is of global public health significance, with millions of incident cases each year. Many cases, particularly in low-prevalence settings, result from the reactivation of latent tuberculosis infection (LTBI); potentially acquired years prior to active disease. Up to one-third of the world’s population has been infected with LTBI, and so may be at risk for future active TB disease. A variety of antituberculosis medications and treatment regimens have now been evaluated in the management of LTBI, with the aim of eradicating tuberculosis bacilli and reducing the likelihood of subsequent reactivation disease. This article reviews LTBI therapies and their use in clinical contexts, and considers future directions for individual and population-based strategies in LTBI management.

Tuberculosis as part of the natural history of HIV infection in developing countries

An enhanced, refocused research agenda is critical to reducing the burden of tuberculosis (TB) in the human immunodeficiency virus (HIV) epidemic in developing countries. TB threatens HIV-infected patients before and after initiation of antiretroviral therapy, is difficult to diagnose, is rapidly fatal when it is drug resistant, and is being spread in clinics and hospitals. Research priorities include improved and point-of-care TB diagnostics; TB treatment and prevention during HIV infection, drug-resistant TB, and childhood TB; and optimization of TB and HIV program integration. With new TB diagnostics and drugs reaching approval, research must focus on effectively deploying these advancements. Research must include evaluations of individual, household, health care, and community approaches. Studies must apply implementation science to determine how to increase and adapt effective interventions to reduce TB burden in the context of HIV infection. Investment in this research will improve the lives of persons infected with HIV and contribute to efforts to reduce the global TB burden.

Community-acquired pneumonia in HIV-infected children: a global perspective

PURPOSE OF REVIEW

Pneumonia is a leading cause of morbidity and death in HIV-infected children. The aim of this study was to review recent advances in the epidemiology, cause, management and prevention of pneumonia in HIV-infected children.

RECENT FINDINGS

Pneumonia remains a major cause of death and hospitalization, particularly in sub-Saharan Africa, where the paediatric HIV epidemic is concentrated. HIV-infected children have a higher risk of developing pneumonia and of more severe disease than immunocompetent children. Bacterial pathogens especially Streptococcus pneumoniae, Staphylococcus aureus and Gram-negative bacteria predominate, with rising rates of antimicrobial resistance. Mycobacterium tuberculosis is increasingly reported to cause acute pneumonia. Pneumocystis jirovecii (PCP) remains an important cause of severe pneumonia especially in infants. Viral infections, especially cytomegalovirus-associated pneumonia are common. Polymicrobial infection is increasingly recognized and associated with a worse prognosis. HIV-exposed, negative children have an increased risk of infection with opportunistic pathogens and a poorer outcome than HIV-unexposed children.Increasing access to highly active antiretroviral therapy (HAART) has reduced the incidence of severe pneumonia, eliminated most opportunistic infections and improved outcome. However, pneumonia remains the major cause of morbidity in HIV-infected children taking HAART. Standard case management guidelines are effective at decreasing mortality but require adaptation for high HIV-prevalence areas. Broad-spectrum antibiotics should be used as empiric therapy. Infants or children who are not taking pneumocystis prophylaxis should be treated for PCP.A number of general or specific preventive strategies are effective including early use of HAART at the time of HIV diagnosis, pathogen-specific immunizations, in particular pneumococcal conjugate vaccine, and antibiotic prophylaxis against PCP.

SUMMARY

Greater access to preventive and treatment strategies, especially PCP prophylaxis, pneumococcal immunization and HAART, are urgently needed in areas of high childhood HIV prevalence.

HIV: primary and secondary prophylaxis for opportunistic infections

INTRODUCTION

Opportunistic infections can occur in up to 40% of people with HIV infection and a CD4 count less than 250/mm(3), although the risks are much lower with use of highly active antiretroviral treatment.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of prophylaxis for Pneumocystis jirovecii pneumonia (PCP) and toxoplasmosis? What are the effects of antituberculosis prophylaxis in people with HIV infection? What are the effects of prophylaxis for disseminated Mycobacterium avium complex (MAC) disease for people with, and without, previous MAC disease? What are the effects of prophylaxis for cytomegalovirus (CMV), herpes simplex virus (HSV), and varicella zoster virus (VZV)? What are the effects of prophylaxis for invasive fungal disease in people with, and without, previous fungal disease? What are the effects of discontinuing prophylaxis against opportunistic pathogens in people on highly active antiretroviral treatment (HAART)? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2008 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 43 systematic reviews, RCTs, or observational studies that met our inclusion criteria.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: aciclovir; antituberculosis prophylaxis; atovaquone; azithromycin (alone or plus rifabutin); clarithromycin (alone, or plus rifabutin and ethambutol); discontinuing prophylaxis for CMV, MAC, and PCP; ethambutol added to clarithromycin; famciclovir; fluconazole; isoniazid; itraconazole; oral ganciclovir; rifabutin (alone or plus macrolides); trimethoprim-sulfamethoxazole; and valaciclovir.

Low rates of hepatotoxicity in HIV-infected children on anti-retroviral therapy with and without isoniazid prophylaxis

This study investigates the incidence of hepatotoxicity in HIV-infected children during anti-retroviral therapy (ART) and the impact of concomitant use of isoniazid preventive therapy. It is a retrospective cohort analysis of HIV-infected children who commenced ART or were followed up between September 1998 and November 2005. Alanine transferase levels were measured at baseline, at 1, 3 and 6 months and then 6 monthly thereafter. Of the 598 children included in the study, 425 were taking ART alone, 73 ART and isoniazid, 39 isoniazid alone and 61 neither isoniazid nor ART. There was no increased risk of hepatotoxicity with ART with or without isoniazid compared to the control group over a 2-year period. Grade 3 or 4 ALT elevations occurred in 19 (3.4%) children, with no cases of fulminant hepatic failure. Severe hepatic events are uncommon in children on ART or isoniazid. There is no increased risk of hepatotoxicity with ART and concurrent isoniazid preventive therapy.

Diagnosis of pulmonary tuberculosis in children: new advances

The global burden of childhood pulmonary TB has been underappreciated, in part due to difficulties in obtaining microbiological confirmation of disease. Most HIV-uninfected children can be diagnosed using a combination of clinical and epidemiological features, tuberculin skin testing and chest radiography, as represented in different scoring systems. However, accurate microbiologic diagnosis has become increasingly important for timely use of effective treatment. Mycobacterial culture confirms the diagnosis of TB and provides drug susceptibility data but is not available in most areas with a high TB prevalence. Moreover, culture has poor sensitivity in children who usually have paucibacillary disease. The HIV epidemic has made definitive diagnosis even more challenging due to nonspecific clinical and radiological signs. In high HIV-prevalence areas, scoring systems have been especially variable, lacking sensitivity and specificity. Newer methods for diagnosis are aimed either at detecting the organism or a specific host immune response. Methods for organism detection have focused on collection of better samples, improved culture techniques, molecular methods or antigen detection. Recent advances include the use of sputum induction for obtaining a more reliable specimen, faster and more sensitive culture methods, and rapid detection of the organism and drug resistance based on nucleic acid amplification. Improved methods for detecting a specific host response have largely focused on the use of IFN-g release assays. Even with newer methods, accurately diagnosing childhood TB may be challenging. Greater efforts to obtain a microbiologic diagnosis should be made in children, even in primary care settings. Further research to develop a more accurate, cost-effective and simple diagnostic test for childhood TB is urgently needed.

The HIV-associated tuberculosis epidemic--when will we act?

Despite policies, strategies, and guidelines, the epidemic of HIV-associated tuberculosis continues to rage, particularly in southern Africa. We focus our attention on the regions with the greatest burden of disease, especially sub-Saharan Africa, and concentrate on prevention of tuberculosis in people with HIV infection, a challenge that has been greatly neglected. We argue for a much more aggressive approach to early diagnosis and treatment of HIV infection in affected communities, and propose urgent assessment of frequent testing for HIV and early start of antiretroviral treatment (ART). This approach should result in short-term and long-term declines in tuberculosis incidence through individual immune reconstitution and reduced HIV transmission. Implementation of the 3Is policy (intensified tuberculosis case finding, infection control, and isoniazid preventive therapy) for prevention of HIV-associated tuberculosis, combined with earlier start of ART, will reduce the burden of tuberculosis in people with HIV infection and provide a safe clinical environment for delivery of ART. Some progress is being made in provision of HIV care to HIV-infected patients with tuberculosis, but too few receive co-trimoxazole prophylaxis and ART. We make practical recommendations about how to improve this situation. Early HIV diagnosis and treatment, the 3Is, and a comprehensive package of HIV care, in association with directly observed therapy, short-course (DOTS) for tuberculosis, form the basis of prevention and control of HIV-associated tuberculosis. This call to action recommends that both HIV and tuberculosis programmes exhort implementation of strategies that are known to be effective, and test innovative strategies that could work. The continuing HIV-associated tuberculosis epidemic needs bold but responsible action, without which the future will simply mirror the past.

Initial response to protease-inhibitor-based antiretroviral therapy among children less than 2 years of age in South Africa: effect of cotreatment for tuberculosis

BACKGROUND

South African guidelines recommend protease-inhibitor-based antiretroviral therapy (ART) with lopinavir-ritonavir for human immunodeficiency virus (HIV)-infected children <36 months of age. We investigated factors associated with viral suppression and mortality among young children initiating ART.

METHODS

Treatment-naive, ART-eligible, HIV-infected children (aged 6-104 weeks) were enrolled in an ART strategies trial in South Africa and initiated protease-inhibitor-based ART. Mortality and the probability of viral suppression (defined as HIV RNA load of <400 copies/mL) by 39 weeks after ART initiation were investigated.

RESULTS

Of 254 children who initiated ART, 99 (39%) were cotreated for tuberculosis during follow-up. The mortality rate was 14%. Factors predicting mortality were lower pre-ART weight-for-age z score and higher HIV RNA load. By 39 weeks, 84% of surviving children achieved viral suppression. Children who were not cotreated for tuberculosis were more likely to achieve viral suppression (94.8%) than were children who were receiving cotreatment at ART initiation (74.2%) or who started tuberculosis cotreatment after ART initiation (51.6%; P < .001). Other factors predicting lower probability of viral suppression were lower pre-ART weight- and length-for-age z score, higher HIV RNA load, and World Health Organization disease stage.

CONCLUSION

High rates of viral suppression can be achieved among infants and young children who initiate protease-inhibitor-based ART. Cotreatment for tuberculosis reduced viral suppression. How best to treat HIV-infected children who require tuberculosis treatment warrants urgent investigation.

A systematic review of the reporting of Data Monitoring Committees' roles, interim analysis and early termination in pediatric clinical trials

BACKGROUND

Decisions about interim analysis and early stopping of clinical trials, as based on recommendations of Data Monitoring Committees (DMCs), have far reaching consequences for the scientific validity and clinical impact of a trial. Our aim was to evaluate the frequency and quality of the reporting on DMC composition and roles, interim analysis and early termination in pediatric trials.

METHODS

We conducted a systematic review of randomized controlled clinical trials published from 2005 to 2007 in a sample of four general and four pediatric journals. We used full-text databases to identify trials which reported on DMCs, interim analysis or early termination, and included children or adolescents. Information was extracted on general trial characteristics, risk of bias, and a set of parameters regarding DMC composition and roles, interim analysis and early termination.

RESULTS

110 of the 648 pediatric trials in this sample (17%) reported on DMC or interim analysis or early stopping, and were included; 68 from general and 42 from pediatric journals. The presence of DMCs was reported in 89 of the 110 included trials (81%); 62 papers, including 46 of the 89 that reported on DMCs (52%), also presented information about interim analysis. No paper adequately reported all DMC parameters, and nine (15%) reported all interim analysis details. Of 32 trials which terminated early, 22 (69%) did not report predefined stopping guidelines and 15 (47%) did not provide information on statistical monitoring methods.

CONCLUSIONS

Reporting on DMC composition and roles, on interim analysis results and on early termination of pediatric trials is incomplete and heterogeneous. We propose a minimal set of reporting parameters that will allow the reader to assess the validity of trial results.

Adherence to isoniazid prophylaxis among HIV-infected children: a randomized controlled trial comparing two dosing schedules

BACKGROUND

Tuberculosis contributes significantly to morbidity and mortality among HIV-infected children in sub-Saharan Africa. Isoniazid prophylaxis can reduce tuberculosis incidence in this population. However, for the treatment to be effective, adherence to the medication must be optimized. We investigated adherence to isoniazid prophylaxis administered daily, compared to three times a week, and predictors of adherence amongst HIV-infected children.

METHODS

We investigated adherence to study medication in a two centre, randomized trial comparing daily to three times a week dosing of isoniazid. The study was conducted at two tertiary paediatric care centres in Cape Town, South Africa. Over a 5 year period, we followed 324 HIV-infected children aged >or= 8 weeks. Adherence information based on pill counts was available for 276 children. Percentage adherence was calculated by counting the number of pills returned. Adherence >or= 90% was considered to be optimal. Analysis was done using summary and repeated measures, comparing adherence to the two dosing schedules. Mean percentage adherence (per child during follow-up time) was used to compare the mean of each group as well as the proportion of children achieving an adherence of >or= 90% in each group. For repeated measures, percentage adherence (per child per visit) was dichotomized at 90%. A logistic regression model with generalized estimating equations, to account for within-individual correlation, was used to evaluate the impact of the dosing schedule. Adjustments were made for potential confounders and we assessed potential baseline and time-varying adherence determinants.

RESULTS

The overall adherence to isoniazid was excellent, with a mean adherence of 94.7% (95% confidence interval [CI] 93.5-95.9); similar mean adherence was achieved by the group taking daily medication (93.8%; 95% CI 92.1-95.6) and by the three times a week group (95.5%; 95% CI 93.8-97.2). Two-hundred and seventeen (78.6%) children achieved a mean adherence of >or= 90%. Adherence was similar for daily and three times a week dosing schedules in univariate (odds ratio [OR] 0.88; 95% CI 0.66-1.17; P = 0.38) and multivariate (adjusted OR 0.85; 95% CI 0.64-1.11; P = 0.23) models. Children from overcrowded homes were less adherent (adjusted OR 0.71; 95% CI 0.54-0.95; P = 0.02). Age at study visit was predictive of adherence, with better adherence achieved in children older than 4 years (adjusted OR 1.96; 95% CI 1.16-3.32; P = 0.01).

CONCLUSION

Adherence to isoniazid was excellent regardless of the dosing schedule used. Intermittent dosing of isoniazid prophylaxis can be considered as an alternative to daily dosing, without compromising adherence or efficacy.

TRIAL REGISTRATION

Clinical Trials NCT00330304.

Lactic acid bacteria population in children diagnosed with human immunodeficiency virus

AIM

To determine the effect of trimethoprim/sulphamethoxazole treatment on the natural population of lactic acid bacteria in the intestinal tract and to determine if any of the strains developed resistance to antibiotics.

METHODS

Lactic acid bacteria were isolated from stool samples of 100 children. The isolates were identified based on biochemical characteristics and DNA profiles obtained from polymerase chain reaction with genus- and species-specific primers. Resistance to sulphamethoxazole, streptomycin, compound sulphonamides, chloramphenicol and vancomycin was tested using the paper-disk method.

RESULTS

The lactic acid bacteria were identified as Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus paracasei, Lactobacillus pentosus, Lactobacillus rhamnosus, Leuconostoc mesenteroides subsp. mesenteroides, Enterococcus spp. and Weissella spp. Lactobacillus plantarum and Bifidobacterium spp. were not isolated. All strains, except two, were sensitive to chloramphenicol and streptomycin. Thirty-five percent of the isolates were resistant to vancomycin, 50% to compound sulphonamides and 66% to sulphamethoxazole.

CONCLUSION

Treatment with trimethoprim/sulphamethoxazole repressed a large number of lactic acid bacteria normally present in the intestinal tract of children. A number of strains were resistant to sulphamethoxazole and may be used as probiotics to correct the imbalance in lactic acid bacteria.

Guidelines for the Prevention and Treatment of Opportunistic Infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics

This report updates and combines into one document earlier versions of guidelines for preventing and treating opportunistic infections (OIs) among HIV-exposed and HIV-infected children, last published in 2002 and 2004, respectively. These guidelines are intended for use by clinicians and other health-care workers providing medical care for HIV-exposed and HIV-infected children in the United States. The guidelines discuss opportunistic pathogens that occur in the United States and one that might be acquired during international travel (i.e., malaria). Topic areas covered for each OI include a brief description of the epidemiology, clinical presentation, and diagnosis of the OI in children; prevention of exposure; prevention of disease by chemoprophylaxis and/or vaccination; discontinuation of primary prophylaxis after immune reconstitution; treatment of disease; monitoring for adverse effects during treatment; management of treatment failure; prevention of disease recurrence; and discontinuation of secondary prophylaxis after immune reconstitution. A separate document about preventing and treating of OIs among HIV-infected adults and postpubertal adolescents (Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents) was prepared by a working group of adult HIV and infectious disease specialists. The guidelines were developed by a panel of specialists in pediatric HIV infection and infectious diseases (the Pediatric Opportunistic Infections Working Group) from the U.S. government and academic institutions. For each OI, a pediatric specialist with content-matter expertise reviewed the literature for new information since the last guidelines were published; they then proposed revised recommendations at a meeting at the National Institutes of Health (NIH) in June 2007. After these presentations and discussions, the guidelines underwent further revision, with review and approval by the Working Group, and final endorsement by NIH, CDC, the HIV Medicine Association (HIVMA) of the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Disease Society (PIDS), and the American Academy of Pediatrics (AAP). The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of the evidence supporting the recommendation so readers can ascertain how best to apply the recommendations in their practice environments. An important mode of acquisition of OIs, as well as HIV infection among children, is from their infected mother; HIV-infected women coinfected with opportunistic pathogens might be more likely than women without HIV infection to transmit these infections to their infants. In addition, HIV-infected women or HIV-infected family members coinfected with certain opportunistic pathogens might be more likely to transmit these infections horizontally to their children, resulting in increased likelihood of primary acquisition of such infections in the young child. Therefore, infections with opportunistic pathogens might affect not just HIV-infected infants but also HIV-exposed but uninfected infants who become infected by the pathogen because of transmission from HIV-infected mothers or family members with coinfections. These guidelines for treating OIs in children therefore consider treatment of infections among all children, both HIV-infected and uninfected, born to HIV-infected women. Additionally, HIV infection is increasingly seen among adolescents with perinatal infection now surviving into their teens and among youth with behaviorally acquired HIV infection. Although guidelines for postpubertal adolescents can be found in the adult OI guidelines, drug pharmacokinetics and response to treatment may differ for younger prepubertal or pubertal adolescents. Therefore, these guidelines also apply to treatment of HIV-infected youth who have not yet completed pubertal development. Major changes in the guidelines include 1) greater emphasis on the importance of antiretroviral therapy for preventing and treating OIs, especially those OIs for which no specific therapy exists; 2) information about the diagnosis and management of immune reconstitution inflammatory syndromes; 3) information about managing antiretroviral therapy in children with OIs, including potential drug--drug interactions; 4) new guidance on diagnosing of HIV infection and presumptively excluding HIV infection in infants that affect the need for initiation of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PCP) in neonates; 5) updated immunization recommendations for HIV-exposed and HIV-infected children, including hepatitis A, human papillomavirus, meningococcal, and rotavirus vaccines; 6) addition of sections on aspergillosis; bartonella; human herpes virus-6, -7, and -8; malaria; and progressive multifocal leukodystrophy (PML); and 7) new recommendations on discontinuation of OI prophylaxis after immune reconstitution in children. The report includes six tables pertinent to preventing and treating OIs in children and two figures describing immunization recommendations for children aged 0--6 years and 7--18 years. Because treatment of OIs is an evolving science, and availability of new agents or clinical data on existing agents might change therapeutic options and preferences, these recommendations will be periodically updated and will be available at http://AIDSInfo.nih.gov.

A substantial and confusing variation exists in handling of baseline covariates in randomized controlled trials: a review of trials published in leading medical journals

OBJECTIVE

Statisticians have criticized the use of significance testing to compare the distribution of baseline covariates between treatment groups in randomized controlled trials (RCTs). Furthermore, some have advocated for the use of regression adjustment to estimate the effect of treatment after adjusting for potential imbalances in prognostically important baseline covariates between treatment groups.

STUDY DESIGN AND SETTING

We examined 114 RCTs published in the New England Journal of Medicine, the Journal of the American Medical Association, The Lancet, and the British Medical Journal between January 1, 2007 and June 30, 2007.

RESULTS

Significance testing was used to compare baseline characteristics between treatment arms in 38% of the studies. The practice was very rare in British journals and more common in the U.S. journals. In 29% of the studies, the primary outcome was continuous, whereas in 65% of the studies, the primary outcome was either dichotomous or time-to-event in nature. Adjustment for baseline covariates was reported when estimating the treatment effect in 34% of the studies.

CONCLUSIONS

Our findings suggest the need for greater editorial consistency across journals in the reporting of RCTs. Furthermore, there is a need for greater debate about the relative merits of unadjusted vs. adjusted estimates of treatment effect.

Pediatric TB: issues related to current and future treatment options

Pediatric TB continues to be a neglected disease in many endemic areas where limited resources restrict the focus of treatment to only the most infectious TB cases. However, recognition that children contribute to a significant proportion of the global TB disease burden and suffer severe TB-related morbidity and mortality is growing. The WHO published guidelines on the management of pediatric TB in 2006 and child-friendly drug formulations have been made available to deserving low-income nations via the Global Drug Fund since 2008. Increased awareness and improved drug availability re-emphasized the considerable programmatic barriers that remain and the difficulty of establishing an accurate diagnosis in resource-limited settings. This article provides an overview of current treatment practices, factors that influence the provision of effective TB therapy to children in endemic areas and potential future advances. It includes a brief summary of the relevant literature and presents the authors’ personal perspectives on issues related to the treatment of pediatric TB.

The clinical burden of tuberculosis among human immunodeficiency virus-infected children in Western Kenya and the impact of combination antiretroviral treatment

CONTEXT

The burden of tuberculosis (TB) disease in children, particularly in HIV-infected children, is poorly described because of a lack of effective diagnostic tests and the emphasis of public health programs on transmissible TB.

OBJECTIVES

The objectives of this study were to describe the observed incidence of and risk factors for TB diagnosis among HIV-infected children enrolled in a large network of HIV clinics in western Kenya.

DESIGN

Retrospective observational study.

SETTING

The USAID-Academic Model Providing Access to Healthcare (AMPATH) Partnership is Kenya's largest HIV/AIDS care system. Since 2001, the program has enrolled over 70,000 HIV-infected patients in 18 clinics throughout Western Kenya.

PATIENTS

This analysis included all HIV-infected children aged 0 to 13 years attending an AMPATH clinic.

MAIN OUTCOME MEASURE

The primary outcome was a diagnosis of any TB, defined either by a recorded diagnosis or by the initiation of anti-TB treatment. Diagnosis of TB is based on a modified Kenneth Jones scoring system and is consistent with WHO case definitions.

RESULTS

There were 6535 HIV-infected children aged 0 to 13 years, eligible for analysis, 50.1% were female. Of these, 234 (3.6%) were diagnosed with TB at enrollment. There were subsequently 765 new TB diagnoses in 4368.0 child-years of follow-up for an incidence rate of 17.5 diagnoses (16.3-18.8) per 100 child-years. The majority of these occurred in the first 6 months after enrollment (IR: 106.8 per 100 CY, 98.4-115.8). In multivariable analysis, being severely immune-suppressed at enrollment (Adjusted Hazard Ratio [AHR]: 4.44, 95% CI: 3.62-5.44), having ever attended school AHR: 2.65, 95% CI: 2.15-3.25), being an orphan (AHR: 1.57, 95% CI: 1.28-1.92), being severely low weight-for-height at enrollment (AHR: 1.46, 95% CI: 1.32-1.62), and attending an urban clinic (AHR: 1.39, 95% CI: 1.16-1.67) were all independent risk factors for having an incident TB diagnosis. Children receiving combination antiretroviral treatment were dramatically less likely to be diagnosed with incident TB (AHR: 0.15, 95% CI: 0.12-0.20).

CONCLUSIONS

These data suggest a high rate of TB diagnosis among HIV-infected children, with severe immune suppression, school attendance, orphan status, very low weight-for-height, and attending an urban clinic being key risk factors. The use of combination antiretroviral treatment reduced the probability of an HIV-infected child being diagnosed with incident TB by 85%.

HIV-1 infection in infants severely impairs the immune response induced by Bacille Calmette-Guérin vaccine

BACKGROUND

Worldwide, most infants born to mothers infected with human immunodeficiency virus (HIV) receive bacille Calmette-Guérin (BCG) vaccine. Tuberculosis is a major cause of death among infants infected with HIV in sub-Saharan Africa, and it should be prevented. However, BCG may itself cause disease (known as "BCGosis") in these infants. Information regarding the immunogenicity of BCG is imperative for the risk/benefit assessment of BCG vaccination in HIV-infected infants; however, no such data exist.

METHODS

We compared BCG-induced CD4 and CD8 T cell responses, as assessed by flow cytometry, in HIV-infected (n=20), HIV-exposed but uninfected (n=25), and HIV-unexposed (n=23) infants, during their first year of life.

RESULTS

BCG vaccination of the 2 HIV-uninfected groups induced a robust response, which was characterized by CD4 T cells expressing interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and/or interleukin (IL)-2. In contrast, HIV-infected infants demonstrated a markedly lower response throughout the first year of life. These infants also had significantly reduced numbers of polyfunctional CD4 T cells coexpressing IFN-gamma, TNF-alpha, and IL-2, a finding that is thought to indicate T cell quality.

CONCLUSIONS

Infection with HIV severely impairs the BCG-specific T cell response during the first year of life. BCG may therefore provide little, if any, vaccine-induced benefit in HIV-infected infants. Considering the significant risk of BCGosis, these data strongly support not giving BCG to HIV-infected infants.

Anti-retroviral therapy reduces incident tuberculosis in HIV-infected children

BACKGROUND

We aimed to estimate the effect of anti-retroviral therapy (ART) on incident tuberculosis (TB) in a cohort of HIV-infected children.

METHODS

We analysed data from ART-naïve, TB disease-free children enrolled between December 2004 and April 2008 into an HIV care program in Kinshasa, Democratic Republic of Congo. To estimate the effect of ART on TB incidence while accounting for time-dependent confounders affected by exposure, a Cox proportional hazards marginal structural model was used.

RESULTS

364 children contributed 596.0 person-years of follow-up. At baseline, the median age was 6.9 years; 163 (44.8%) were in HIV clinical stage 3 or 4. During follow-up, 242 (66.5%) children initiated ART and 81 (22.3%) developed TB. At TB diagnosis, 41 (50.6%) were receiving ART. The TB incidence rate in those receiving ART was 10.2 per 100 person-years [95% confidence interval (CI) 7.4-13.9] compared with 20.4 per 100 person-years (95% CI 14.6-27.8) in those receiving only primary HIV care. TB incidence decreased with time on ART, from 18.9 per 100 person-years in the first 6 months to 5.3 per 100 person-years after 12 months of ART. The model-estimated TB hazard ratio for ART was 0.51 (95% CI 0.27-0.94).

CONCLUSIONS

For HIV-infected children in TB-endemic areas, ART reduces the hazard of developing TB by 50%.

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.

A package of primary health care services for comprehensive family-centred HIV/AIDS care and treatment programs in low-income settings

Particularly in resource-limited settings, HIV/AIDS is a family concern. Separate services for children and adults may make accessing care more difficult for families than services where family members can be cared for together. Implicit in comprehensive, family-centred approaches to care are the broader notions of longitudinal primary care and linkages to other services, including those based in communities. As highly-active antiretroviral therapy becomes more available, and the direct burden of HIV-associated morbidity diminishes, HIV-infected individuals require primary care that goes beyond exclusive management of HIV and related conditions, including preventive services and the management of common medical issues. The prevention of tuberculosis, diarrhoea, and, in endemic regions, malaria; the addressing of debilitating depression; cervical screening; and the management of chronic cardiovascular disease and its risk factors are all of benefit to patients accessing HIV/AIDS care. Packaging such services is an effective means both of standardizing care within a program and of ensuring patients receives a full roster of available interventions. As family-centred care models develop in resource-limited settings, the availability of evidence-based service packages such as presented here will help program designers prioritize available human and materiel resources toward those interventions that improve patients' global health and well being.

Treatment of tuberculosis in children

The treatment of children with TB is influenced by a number of factors specific to both the bacterium and the child. We review the variables impacting the selection of individual medications; indications, pharmacology, dosing and side effects for first- and second-line agents; adjunctive therapy; and special cases, including treatment of TB in HIV-infected children and multidrug-resistant TB. Finally, evolving trends in TB therapy, such as the impact of HIV and multidrug-resistant TB on future therapeutics, emerging or re-emerging medication options, shorter-course regimens and immunomodulation, are discussed.

High incidence of tuberculosis among HIV-infected infants: evidence from a South African population-based study highlights the need for improved tuberculosis control strategies

BACKGROUND

There are limited population-based estimates of tuberculosis incidence among human immunodeficiency virus (HIV)-infected and HIV-uninfected infants aged < or =12 months. We aimed to estimate the population-based incidence of culture-confirmed tuberculosis among HIV-infected and HIV-uninfected infants in the Western Cape Province, South Africa.

METHODS

The incidences of pulmonary, extrapulmonary, and disseminated tuberculosis were estimated over a 3-year period (2004-2006) with use of prospective representative hospital surveillance data of the annual number of culture-confirmed tuberculosis cases among infants. The total number of HIV-infected and HIV-uninfected infants was calculated using population-based estimates of the total number of live infants and the annual maternal HIV prevalence and vertical HIV transmission rates.

RESULTS

There were 245 infants with culture-confirmed tuberculosis. The overall incidences of tuberculosis were 1596 cases per 100,000 population among HIV-infected infants (95% confidence interval [CI], 1151-2132 cases per 100,000 population) and 65.9 cases per 100,000 population among HIV-uninfected infants (95% CI, 56-75 cases per 100,000 population). The relative risk of culture-confirmed tuberculosis among HIV-infected infants was 24.2 (95% CI, 17-34). The incidences of disseminated tuberculosis were 240.9 cases per 100,000 population (95% CI, 89-433 cases per 100,000 population) among HIV-infected infants and 14.1 cases per 100,000 population (95% CI, 10-18 cases per 100,000 population) among HIV-uninfected infants (relative risk, 17.1; 95% CI, 6-34).

CONCLUSIONS

This study indicates the magnitude of the tuberculosis disease burden among HIV-infected infants and provides population-based comparative incidence rates of tuberculosis among HIV-infected infants. This high risk of tuberculosis among HIV-infected infants is of great concern and may be attributable to an increased risk of tuberculosis exposure, increased immune-mediated tuberculosis susceptibility, and/or possible limited protective effect of bacille Calmette-Guérin vaccination. Improved tuberculosis control strategies, including maternal tuberculosis screening, contact tracing of tuberculosis-exposed infants coupled with preventive chemotherapy, and effective vaccine strategies, are needed for infants in settings where HIV infection and tuberculosis are highly endemic.

Confronting TB/HIV in the era of increasing anti-TB drug resistance

HIV associated TB is a major public health problem. In 2006, it was estimated that there were over 700,000 people who suffered from HIV associated TB, of whom about 200, 000 have died. The burden of HIV associated TB is greatest in Sub-Saharan Africa where the TB epidemic is primarily driven by HIV. There has been steady progress made in reducing the burden of HIV in TB patients with an increasing number of TB patients tested for HIV and provided with cotrimoxazole preventive therapy (CPT) and anti-retroviral treatment (ART). Less progress is being made to reduce the burden of TB in people living with HIV. The number of HIV infected persons reported to have been screened for TB was less than 1% while Isoniazid preventive therapy was reported to have been provided to less than 0.1% of eligible persons in 2006. A major push is urgently needed to accelerate the implementation of three important interventions. The three are Intensified TB Screening (ICF) among people living with HIV, the provision of Isoniazid Preventive Therapy (IPT) and TB Infection Control(IC). These interventions are best carried out by HIV control programmes which should therefore be encouraged to take greater responsibility in implementing these interventions.

Worsening and unmasking of tuberculosis in HIV-1 infected patients after initiating highly active anti-retroviral therapy in Uganda

OBJECTIVES

To determine the proportion of patients developing active tuberculosis (TB) versus that of patients who experience worsening of TB, after initiating highly active anti retroviral therapy (HAART).

METHODS

Charts of HAART naïve patients with or without clinically active TB who consecutively commenced HAART at Mulago Hospital Infectious Diseases Institute were reviewed. Patients were assessed for worsening of TB on treatment or development of new active TB (unmasking of TB) after initiating HAART.

RESULTS

Of 271 patients without active TB at baseline who initiated HAART, 16 (5.9%) developed active TB within 6 months (early unmasking) and 10 (2.7%) after 6 months (late unmasking). Seven of 10 late unmasking patients had a past history of treatment for a TB disease episode. Of 45 patients who commenced HAART with coexisting active TB, 13 (29%) experienced worsening of TB symptoms, signs and/or radiological features. Nine of these 45 commenced HAART during the intensive phase of TB treatment, of whom 2 (22%) experienced worsening of TB. Thirty six of 45 started HAART during the continuation phase of TB treatment of whom 11 (31%), experienced worsening of TB. The median time from initiation of HAART to worsening of TB in patients on concurrent active TB treatment was 5 weeks, and 18 weeks to unmasking of new active tuberculosis.

CONCLUSION

Unmasking of TB was commonest in the first 6 months of HAART and declined in the subsequent months with most in the late unmasking group being TB recurrences. Worsening of TB occurred even after HAART was delayed to the continuation phase of TB treatment.

Ensuring the involvement of children in the evaluation of new tuberculosis treatment regimens

William Burman and colleagues review the barriers to involving children in studies of new tuberculosis treatments and recommend strategies for overcoming these barriers.

Paediatric tuberculosis

Tuberculosis continues to cause an unacceptably high toll of disease and death among children worldwide, particularly in the wake of the HIV epidemic. Increased international travel and immigration have led to a rise in childhood tuberculosis rates even in traditionally low burden, industrialised settings, and threaten to promote the emergence and spread of multidrug-resistant strains. Whereas intense scientific and clinical research efforts into novel diagnostic, therapeutic, and preventive interventions have focused on tuberculosis in adults, childhood tuberculosis has been relatively neglected. However, children are particularly vulnerable to severe disease and death following infection, and those with latent infection become the reservoir for future transmission following disease reactivation in adulthood, fuelling future epidemics. Further research into the epidemiology, immune mechanisms, diagnosis, treatment, and prevention of childhood tuberculosis is urgently needed. Advances in our understanding of tuberculosis in children would provide insights and opportunities to enhance efforts to control this disease.

Managing HIV in the PICU--the experience at the Red Cross War Memorial Children's Hospital in Cape Town

The HIV pandemic has affected children throughout the developing world. This article describes the experience of the Paediatric Intensive Care Unit at the Red Cross War Memorial Children's Hospital in Cape Town, South Africa. Over the last 20 years we have improved our management of HIV infected children requiring intensive care admission. In the absence of anti-retroviral therapy, long term outcomes from PICU admission of HIV infected children have not improved significantly, and it is debatable whether PICU admission is justified. Once anti-retroviral therapy is available to children, there may be significant improvements in outcome and possible affected children should be admitted to the PICU if resources are available.

Tuberculosis in children

Tuberculosis (TB) control poses one of the major global health challenges in the new millennium. Children in TB-endemic areas suffer severe TB related morbidity and mortality, despite the availability of cheap and effective TB treatment. However, providing an accurate TB diagnosis together with access to supervised, child friendly treatment remains difficult in resource-limited settings. This review provides a broad overview of recent advances related to child TB, focusing on intra-thoracic disease manifestations. It summarizes current understanding of TB epidemiology, disease prevention, diagnosis and treatment, but also introduces novel concepts for further discussion and future evaluation.

High incidence of antimicrobial resistant organisms including extended spectrum beta-lactamase producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus in nasopharyngeal and blood isolates of HIV-infected children from Cape Town, South Africa

Background

There is little information on nasopharyngeal (NP) flora or bacteremia in HIV-infected children. Our aim was to describe the organisms and antimicrobial resistance patterns in children enrolled in a prospective study comparing daily and three times weekly trimethoprim-sulfamethoxazole (TMP-SMX) and isoniazid (INH) or placebo prophylaxis.

Methods

NP swabs were taken at baseline from HIV-infected children enrolled in the study. Standard microbiological techniques were used. Children were grouped according to previous or current exposure to TMP-SMX and whether enrolled to the study during a period of hospitalization. Blood culture results were also recorded within 12 months of baseline.

Results

Two hundred and three children, median age 1.8 (Interquartile [IQ]: 0.7–4) years had NP swabs submitted for culture. One hundred and eighty-four (90.7%) had either stage B or C HIV disease. One hundred and forty-one (69.8%) were receiving TMP-SMX and 19 (9.4%) were on antiretroviral therapy. The majority, 168 (82%) had a history of hospitalization and 91 (44.8%) were enrolled during a period of hospitalization. Thirty-two subjects (16.2%) died within 12 months of study entry.

One hundred and eighty-one potential pathogens were found in 167 children. The most commonly isolated organisms were Streptococcus pneumoniae (48: 22.2%), Gram-negative respiratory organisms (Haemophilus influenzae and Moraxella catarrhalis) (47: 21.8%), Staphylococcus aureus (44: 20.4%), Enterobacteriaceae 32 (14.8%) and Pseudomonas 5 (2.3%).

Resistance to TMP-SMX occurred in > 80% of pathogens except for M. catarrhalis (2: 18.2% of tested organisms). TMP-SMX resistance tended to be higher in those receiving it at baseline (p = 0.065). Carriage of Methicillin resistant S. aureus (MRSA) was significantly associated with being on TMP-SMX at baseline (p = 0.002). Minimal inhibitory concentrations (MIC) to penicillin were determined for 18 S. pneumoniae isolates: 7 (38.9%) were fully sensitive (MIC ≤ 0.06 μg/ml), 9 (50%) had intermediate resistance (MIC 0.12 – 1 μg/ml) and 2 (11.1%) had high level resistance (MIC ≥2 μg/ml). Fifty percent of Enterobacteriaceae produced extended spectrum beta-lactamases (ESBL) (resistant to third generation cephalosporins) and 56% were resistant to gentamicin. Seventy-seven percent of S. aureus were MRSA. Carriage of resistant organisms was not associated with hospitalization.

On multivariate logistic regression, risk factors for colonization with Enterobacteriaceae were age ≤ one year (Odds ratio 4.4; 95% Confidence Interval 1.9–10.9; p = 0.0008) and CDC stage C disease (Odds ratio 3.6; 95% Confidence Interval 1.5–8.6; p = 0.005)

Nineteen (9.4%) subjects had 23 episodes of bacteremia. Enterobacteriaceae were most commonly isolated (13 of 25 isolates), of which 6 (46%) produced ESBL and were resistant to gentamicin.

Conclusion

HIV-infected children are colonized with potential pathogens, most of which are resistant to commonly used antibiotics. TMP-SMX resistance is extremely common. Antibiotic resistance is widespread in colonizing organisms and those causing invasive disease. Antibiotic recommendations should take cognizance of resistance patterns. Antibiotics appropriate for ESBL-producing Enterobacteriaceae and MRSA should be used for severely ill HIV-infected children in our region. Further study of antibiotic resistance patterns in HIV-infected children from other areas is needed.

Opportunistic pathogens in AIDS: trends, diagnosis and priorities

The second International Conference on Opportunistic Pathogens in AIDS was organized by the Department of Laboratory Medicine, All India Institute of Medical Sciences (New Delhi, India). The conference was held at the All India Institute of Medical Sciences in India between the 27th and 29th January 2008, and was attended by 225 participants representing 21 countries. The conference focused on trends, diagnosis and management of coinfections among HIV patients. In addition, as part of this conference, a symposium was held on the links between substance abuse, HIV and neuropathology.

Clinical presentation and outcome of tuberculosis in human immunodeficiency virus infected children on anti-retroviral therapy

Background

The tuberculosis (TB) and human immunodeficiency virus (HIV) epidemics are poorly controlled in sub-Saharan Africa, where highly active antiretroviral treatment (HAART) has become more freely available. Little is known about the clinical presentation and outcome of TB in HIV-infected children on HAART.

Methods

We performed a comprehensive file review of all children who commenced HAART at Tygerberg Children's Hospital from January 2003 through December 2005.

Results

Data from 290 children were analyzed; 137 TB episodes were recorded in 136 children; 116 episodes occurred before and 21 after HAART initiation; 10 episodes were probably related to immune reconstitution inflammatory syndrome (IRIS). The number of TB cases per 100 patient years were 53.3 during the 9 months prior to HAART initiation, and 6.4 during post HAART follow-up [odds ratio (OR) 16.6; 95% confidence interval (CI) 12.5–22.4]. A positive outcome was achieved in 97/137 (71%) episodes, 6 (4%) cases experienced no improvement, 16 (12%) died and the outcome could not be established in 18 (13%). Mortality was less in children on HAART (1/21; 4.8%) compared to those not on HAART (15/116; 12.9%).

Conclusion

We recorded an extremely high incidence of TB among HIV-infected children, especially prior to HAART initiation. Starting HAART at an earlier stage is likely to reduce morbidity and mortality related to TB, particularly in TB-endemic areas. Management frequently deviated from standard guidelines, but outcomes in general were good.

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.

Chronic lung disease in human immunodeficiency virus (HIV) infected children

The development of chronic lung disease is common in HIV-infected children. The spectrum of chronic HIV-associated lung disease includes lymphocytic interstitial pneumonia (LIP), chronic infections, immune reconstitution inflammatory syndrome (IRIS), bronchiectasis, malignancies, and interstitial pneumonitis. Chronic lung disease may result from recurrent or persistent pneumonia due to bacterial, mycobacterial, viral, fungal or mixed infections. In high tuberculosis (TB) prevalence areas, M. tuberculosis is an important cause of chronic respiratory illness. With increasing availability of highly active antiretroviral therapy (HAART) for children in developing countries, a rise in the incidence of IRIS due to mycobacterial or other infections is being reported. Diagnosis of chronic lung disease is based on chronic symptoms and persistent chest X-ray changes but definitive diagnosis can be difficult as clinical and radiological findings may be non-specific. Distinguishing LIP from miliary TB remains a difficult challenge in HIV-infected children living in high TB prevalence areas. Treatment includes therapy for specific infections, pulmonary clearance techniques, corticosteroids for children with LIP who are hypoxic or who have airway compression from tuberculous nodes and HAART. Children who are taking TB therapy and HAART need adjustments in their drug regimes to minimize drug interactions and ensure efficacy. Preventative strategies include immunization, chemoprophylaxis, and micronutrient supplementation. Early use of HAART may prevent the development of chronic lung disease.

Diagnostic and management challenges for childhood tuberculosis in the era of HIV

The diagnosis and management of childhood tuberculosis (TB) pose substantial challenges in the era of the human immunodeficiency virus (HIV) epidemic. The highest TB incidences and HIV infection prevalences are recorded in sub-Saharan Africa, and, as a consequence, children in this region bear the greatest burden of TB/HIV infection. The tuberculin skin test (TST), which is the standard marker of Mycobacterium tuberculosis infection in immunocompetent children, has poor sensitivity when used in HIV-infected children. Novel T cell assays may offer higher sensitivity and specificity than the TST, but these tests still fail to make the crucial distinction between latent M. tuberculosis infection and active disease and are limited by cost considerations. Symptom-based diagnostic approaches are less helpful in HIV-infected children, because of the difficulty of differentiating TB-related symptoms from those caused by other HIV-associated conditions. Knowing the HIV infection status of all children with suspected TB is helpful because it improves clinical management. HIV-infected children are at increased risk of developing active disease after TB exposure/infection, which justifies the use of isoniazid preventive therapy once active TB has been excluded. The higher mortality and relapse rates noted among HIV-infected children with active TB who are receiving standard TB treatment highlight the need for further research to define optimal treatment regimens. HIV-infected children should also receive appropriate supportive care, including cotrimoxazole prophylaxis, and antiretroviral therapy, if indicated. Despite the difficulties experienced in resource-limited countries, the management of children with TB/HIV infection could be vastly improved by better implementation of readily available interventions.

Clinical management of HIV infection in children

PURPOSE OF REVIEW

The aim of this article is to review recent advances in the clinical care of HIV-infected children.

RECENT FINDINGS

Obstacles to diagnosing HIV in children and providing clinical care to those HIV infected relate to a number of technical and operational factors. Most countries now have antiretroviral treatment guidelines and have incorporated co-trimoxazole prophylaxis for infected and exposed infants and children. Implementation lags behind policy and technical recommendations. Optimal early infant feeding remains difficult and, while breastfeeding remains the safest feeding option for child survival, it carries with it the risk of HIV acquisition. Recent data suggest HIV-free survival at 18 months is comparable in infants who are replacement-fed or exclusively breastfed for the first 6 months of life. Antiretroviral treatment efficacy in children is now well documented. Optimal timing of initiation of antiretroviral treatment remains uncertain; in general it is started earlier, especially in infants. Children starting treatment in infancy are surviving and reaching adulthood; new problems of managing the highly treatment-experienced and adolescents are emerging.

SUMMARY

New antiretroviral drugs and classes will be needed for the future; research is urgently required to characterize optimal nutritional interventions, interpretation of immunological and virological parameters, and develop diagnostic tools for use in health services with limited infrastructure and capacity.