Treatment of latent tuberculosis infection in HIV infected persons

Isoniazid preventive therapy among HIV infected patients on antiretroviral therapy diagnosed with latent tuberculosis: A retrospective assessment of the outcome in Tanzania

BACKGROUND

People infected with HIV are at a higher risk up to 20-folds of developing active TB than those not infected with HIV. Isoniazid Preventive Therapy (IPT) is employed in HIV eligible individuals to prevent progression of active tuberculosis (TB) disease. However, there is limited data on the efficacy of IPT in clinical settings in Tanzania and other parts of the world. This study was carried to assess the real-time IPT effectiveness in preventing TB incidences among HIV infected individuals on antiretroviral therapy.

METHODS

A retrospective cohort study was carried employing secondary data of 1000 HIV infected individuals receiving anti-retroviral therapy. TB incidence and associated factors were determined after a four years follow-up.

RESULTS

A total of 1000 people were enrolled in the study. The mean age was 44.87 years. The incidence rate was 7.37/1000 person-years (PY) [95% confidence interval (CI) 3.96-13.71]. One percent (1%) of patients developed active tuberculosis within four years of follow up after receiving isoniazid tablets as part of IPT.

CONCLUSION

IPT has a high efficacy in preventing active TB development among HIV infected individuals on ART in clinical settings thus warranting the scale up of IPT services in the country.

Effect of Isoniazid Prophylaxis Therapy on the Prevention of Tuberculosis Incidence and Associated Factors Among HIV Infected Individuals in Northwest Ethiopia: Retrospective Cohort Study

Background

Treating latent tuberculosis (TB) infection with Isoniazid (INH) among human immune virus (HIV) infected patients reduces active TB occurrence and death by 62% and 26%, respectively. Even though other studies show aforementioned evidence, TB incidence and its associated factors among HIV-infected individuals who were on INH and never on INH is not well studied in northwest Ethiopia. Therefore, this study tried to assess the effect of INH prophylaxis in TB prevention and associated factors among HIV-infected individuals.

Methods

Data were extracted from charts of HIV-infected clients who completed INH (193) and were never on INH (198) after a simple random sampling selection was done among newly diagnosed patients on follow-up from 2008 to 2015. After data were collected, it was entered into Epi info version 7 and exported to SPSS version 22 for analysis. Cox regression model was fitted and the hazard ratio was reported.

Results

In this study, the overall TB incidence rate among HIV patients was 3.5/100 person-years (PY) [95% CI: 2.55, 4.82]. But it was 7.1/100 PY among patients who were never on INH and 0.35/100 PY among patients who completed INH. INH completed [adjusted hazard ratio (AHR) = 0.08, 95% CI: 0.02–0.37], on anti-retroviral therapy (ART) [AHR = 0.02, 95% CI: 0.01–0.04], baseline World Health Organization (WHO) stage I & II [AHR =0.22, 95% CI: 0.08–0.62] and baseline CD4 ≤ 350 [AHR=3.76, 95% CI: 1.39–10.18] were significantly associated with TB incidence.

Conclusion

Putting patients on INH for 6 months and ART were protective factors against TB. Therefore, health institutions are recommended to provide INH after ruling out active TB and contraindications for HIV-infected individuals.

Protective impacts of household-based tuberculosis contact tracing are robust across endemic incidence levels and community contact patterns

There is an emerging consensus that achieving global tuberculosis control targets will require more proactive case finding approaches than are currently used in high-incidence settings. Household contact tracing (HHCT), for which households of newly diagnosed cases are actively screened for additional infected individuals is a potentially efficient approach to finding new cases of tuberculosis, however randomized trials assessing the population-level effects of such interventions in settings with sustained community transmission have shown mixed results. One potential explanation for this is that household transmission is responsible for a variable proportion of population-level tuberculosis burden between settings. For example, transmission is more likely to occur in households in settings with a lower tuberculosis burden and where individuals mix preferentially in local areas, compared with settings with higher disease burden and more dispersed mixing. To better understand the relationship between endemic incidence levels, social mixing, and the impact of HHCT, we developed a spatially explicit model of coupled household and community transmission. We found that the impact of HHCT was robust across settings of varied incidence and community contact patterns. In contrast, we found that the effects of community contact tracing interventions were sensitive to community contact patterns. Our results suggest that the protective benefits of HHCT are robust and the benefits of this intervention are likely to be maintained across epidemiological settings.

[The treatment of tuberculosis under current conditions]

AIM

Study of the current state of problems of treatment of patients with tuberculosis based on literature data and their own experience.

MATERIALS AND METHODS

In the Russian Federation, the number and proportion of patients with co-infection with HIV/tuberculosis continues to increase against the background of improvement in the main epidemiological indicants for tuberculosis. In 2017, 20.9% of newly diagnosed tuberculosis patients had HIV infection. The combination of the two infections significantly complicates the further improvement of the situation with tuberculosis, and the appearance of drug-resistant strains of Mycobacterium tuberculosis sometimes completely neutralizes the results of chemotherapy. The article describes the schemes of modern tuberculosis chemotherapy taking into account HIV/tuberculosis co-infection, as well as MDR in combination with surgical treatment methods, as well as analyzes the data of epidemiological monitoring of treatment of 1115 tuberculosis patients newly diagnosed in 2017 in Moscow, 360 tuberculosis patients with MDR MBT (cohort 20132014), the results of treatment with the use of new chemotherapy regimens for tuberculosis (bedaquiline, linezolid, moxifloxacin) in 36 patients, the effectiveness and safety of surgical methods in 192 patients.

RESULTS

The application of new individualized anti-TB chemotherapy schedules in patients with HIV co-infection/tuberculosis with MDR-MBT has allowed to improve the treatment efficacy. The surgical intervention combined with modern chemotherapy regimens in patients with HIV/tuberculosis co-infection with MDR MBT has been proved to be effective and safe, contributes to the improving the results of treatment for this category of patients.

CONCLUSION

The confluence of two global problems of co-infection HIV/TB and MDR TB, significantly prevents from the end of the tuberculosis epidemic in the world. At the same time, advances in the development and implementation of new anti-TB drugs and surgical treatment methods give hope for significant progress for resolving this situation.

Adolescent tuberculosis

Adolescence is characterised by a substantial increase in the incidence of tuberculosis, a known fact since the early 20th century. Most of the world's adolescents live in low-income and middle-income countries where tuberculosis remains common, and where they comprise a quarter of the population. Despite this, adolescents have not yet been addressed as a distinct population in tuberculosis policy or within tuberculosis treatment services, and emerging evidence suggests that current models of care do not meet their needs. This Review discusses up-to-date information about tuberculosis in adolescence, with a focus on the management of infection and disease, including HIV co-infection and rifampicin-resistant tuberculosis. We outline the progress in vaccine development and highlight important directions for future research.

Implementation of Isoniazid Preventive Therapy Among HIV-Infected Children at Health Facilities in Nairobi County, Kenya: A Cross-Sectional Study

BACKGROUND

HIV is the strongest risk factor for developing tuberculosis (TB) among people with latent or new Mycobacterium tuberculosis infection. Isoniazid preventive therapy (IPT) reduces the risk of active TB among people living with HIV by up to 62%. Despite evidence that IPT is safe and efficacious, its provision remains low globally. The current study aimed at documenting IPT uptake, adherence, and completion rates, as well as the correlates of IPT uptake among HIV-infected children in Kenya. The study also assessed the knowledge, attitude, and practices of health-care workers (HCWs) with regard to IPT.

METHODS

A health facility-based cross-sectional study was conducted. Data were collected from caregivers of HIV-infected children as well as HCWs using an interviewer-administered questionnaire. Logistic regression was used to determine the factors associated with IPT uptake.

RESULTS

The study enrolled 111 child-caregiver dyads. Most of the caregivers were female (n=75, 77.3%) and HIV-positive (n=82, 85.4%). The majority of children were male (n=65, 58.6%) and on ART (n=106, 95.5%). Overall, 59 children were on IPT (uptake of 53.2%, 95% confidence interval [CI], 43.9% to 62.4%). Out of the 25 children who had been on IPT for more than 6 months, 22 (88.0%) successfully completed the 6-month course of treatment. Further, 27 of the 34 children (78.4%) who were on IPT at the time of the study demonstrated satisfactory adherence to the therapy (no doses missed). The caregivers' attributes that were associated with IPT uptake included having a secondary school education (adjusted odds ratio [aOR] 0.13; 95% CI, 0.03 to 0.67) and having been on IPT (aOR 27.50; 95% CI, 5.39 to 140.28). The characteristics of children that were significantly associated with IPT uptake were higher median baseline CD4 count (P=.007) and higher median current CD4 count (P=.024).

CONCLUSION

The study demonstrated suboptimal IPT uptake but favourable adherence and treatment completion rates. There was almost universal awareness of IPT within the study sample. Furthermore, the majority of the HCWs had a favourable attitude towards IPT. However, the attendant IPT practices were inadequate, with majority of HCWs reporting that they had never initiated IPT, prescribed IPT within the last 12 months, or renewed an isoniazid prescription.

Breakthrough tuberculosis disease among people with HIV - Should we be worried? A retrospective longitudinal study

Introduction

Isoniazid preventive therapy (IPT) is a proven means to prevent tuberculosis (TB) disease among people living with HIV (PLHIV). However, there is a concern that patients often develop tuberculosis disease while receiving IPT, defined here as breakthrough tuberculosis, which may affect treatment outcome. In this study, we assessed the magnitude and determinants of breakthrough tuberculosis.

Methods

A multisite retrospective longitudinal study from the year 2005 to 2014 involving 11 randomly selected hospitals from the Addis Ababa, SNNPR (Southern Nations Nationalities and Peoples Region), and Gambela regions of Ethiopia was carried out to assess the occurrence of breakthrough tuberculosis. Cox regression analysis was used to study factors associated with breakthrough TB.

Results

4,484 patients in chronic HIV care received IPT. Eighty percent of the same number received antiretroviral therapy (ART). Tuberculosis developed in 88 of 4,484 (2%) patients of which 24 (0.5%) were diagnosed while receiving IPT. Breakthrough TB incidence was 1106 per 100,000 person-years (PY) (95% CI: 742–1651) while TB incidence after completing IPT was 624 per 100,000 PY (95% CI: 488–797). Seven of the 24 (29%) breakthrough TB cases were diagnosed within the first month of IPT initiation. Of 15 patients who developed breakthrough TB while on ART, nine (60%) were diagnosed within the first six months of ART initiation. Having high CD4 cell count and being on ART were associated with having lower risk of developing TB and breakthrough TB.

Conclusion

Breakthrough TB was uncommon in the study setting. Even then, taking ART reduced the risk of its occurrence. Slightly more than a quarter of the cases of breakthrough TB occurred in the first month of treatment and may be existing undiagnosed TB cases which were missed during diagnostic work-up.

Factors affecting the acceptability of isoniazid preventive therapy among healthcare providers in selected HIV clinics in Nairobi County, Kenya: a qualitative study

OBJECTIVE

Despite being globally recommended as an effective intervention in tuberculosis (TB) prevention among people living with HIV, isoniazid preventive therapy (IPT) implementation remains suboptimal, especially in sub-Saharan Africa. This study explored the factors influencing the acceptability of IPT among healthcare providers in selected HIV clinics in Nairobi County, Kenya, a high HIV/TB burden country.

DESIGN

A qualitative study was conducted using in-depth interviews with healthcare providers in selected HIV clinics. All conversations were audio recorded, transcribed verbatim and analysed using a thematic approach.

SETTING

The study was conducted in the HIV clinics of three purposefully selected public healthcare facilities in Nairobi County, Kenya between February 2017 and April 2017.

PARTICIPANTS

Eighteen purposefully selected healthcare providers (clinicians, nurses, pharmacists and counsellors) working in the HIV clinics participated in the study.

RESULTS

Provider acceptability of IPT was influenced by factors relating to the organisational context, provider training on IPT and their perception on its efficacy, length and clarity of IPT guidelines and standard operation procedures, as well as structural factors (policy, physical and work environment). Inadequate high-level commitment and support for the IPT programme by programme managers and policy-makers were found to be the major barriers to successful IPT implementation in our study context.

CONCLUSION

This study provides insight into the complexity of factors affecting the IPT implementation in Kenya. Ensuring optimal acceptability of IPT among healthcare providers will require an expanded depth of engagement by policy-makers and IPT programme managers with both providers and patients, as well as on-the-job design specific actions to support providers in implementation. Such high-level commitment and support are consequently essential for quality delivery of the intervention.

Prevalence and Risk Factors of Active TB among Adult HIV Patients Receiving ART in Northwestern Tanzania: A Retrospective Cohort Study

INTRODUCTION

Although ART has improved the outcome of people living with HIV/AIDS, still some patients develop TB while receiving ART. The literature on the magnitude of this problem is still scarce in our setting especially northwestern Tanzania. This study was designed to determine the prevalence of active TB among HIV patients on ART and assess its potential risk factors.

METHODS

A retrospective cohort study was done among adult HIV-positive patients initiated on ART at Bugando Medical Centre. Patients who were TB positive before ART initiation were excluded. Data regarding demographic, clinical, and laboratory information, TB status on receipt of ART, and time on ART were collected and analyzed using STATA 11 to determine the prevalence of TB and its associated factors.

RESULTS

In total, 391 patients were enrolled in this study. The median age was 39 (32-46) years, and a total of 129 (32.99%) participants had CD4 counts <200 cells/µl and 179 (45.78%) had WHO stage 3 and 4 illnesses. A total of 43 (11.0%) participants developed TB while receiving ART which was independently associated with male gender (OR = 2.9; p=0.007), WHO clinical stage 3 and 4 (OR = 1.4; p=0.029), baseline CD4 count <200 cells/µl (OR = 9.1; p < 0.001), and having not used IPT (OR = 3.1; p=0.05).

CONCLUSIONS

Active TB is prevalent among HIV patients while receiving ART in northwestern Tanzania which is independently associated with male gender, advanced HIV disease, and nonuse of IPT. Universal HIV testing could reduce late HIV diagnosis and hence reduce the risk of developing TB while receiving ART in our setting. Also IPT should be widely used for those who are negative for TB on screening.

ERS/ECDC Statement: European Union standards for tuberculosis care, 2017 update

The International Standards for Tuberculosis Care define the essential level of care for managing patients who have or are presumed to have tuberculosis, or are at increased risk of developing the disease. The resources and capacity in the European Union (EU) and the European Economic Area permit higher standards of care to secure quality and timely TB diagnosis, prevention and treatment. On this basis, the European Union Standards for Tuberculosis Care (ESTC) were published in 2012 as standards specifically tailored to the EU setting. Since the publication of the ESTC, new scientific evidence has become available and, therefore, the standards were reviewed and updated.A panel of international experts, led by a writing group from the European Respiratory Society (ERS) and the European Centre for Disease Prevention and Control (ECDC), updated the ESTC on the basis of new published evidence. The underlying principles of these patient-centred standards remain unchanged. The second edition of the ESTC includes 21 standards in the areas of diagnosis, treatment, HIV and comorbidities, and public health and prevention.The ESTC target clinicians and public health workers, provide an easy-to-use resource and act as a guide through all the required activities to ensure optimal diagnosis, treatment and prevention of TB.

Treatment of Latent Tuberculosis Infection

There are approximately 56 million people who harbor Mycobacterium tuberculosis that may progress to active tuberculosis (TB) at some point in their lives. Modeling studies suggest that if only 8% of these individuals with latent TB infection (LTBI) were treated annually, overall global incidence would be 14-fold lower by 2050 compared to incidence in 2013, even in the absence of additional TB control measures. This highlights the importance of identifying and treating latently infected individuals, and that this intervention must be scaled up to achieve the goals of the Global End TB Strategy. The efficacy of LTBI treatment is well established, and the most commonly used regimen is 9 months of daily self-administered isoniazid. However, its use has been hindered by limited provider awareness of the benefits, concern about potential side effects such as hepatotoxicity, and low rates of treatment completion. There is increasing evidence that shorter rifamycin-based regimens are as effective, better tolerated, and more likely to be completed compared to isoniazid. Such regimens include four months of daily self-administered rifampin monotherapy, three months of once weekly directly observed isoniazid-rifapentine, and three months of daily self-administered isoniazid-rifampin. The success of LTBI treatment to prevent additional TB disease relies upon choosing an appropriate regimen individualized to the patient, monitoring for potential adverse clinical events, and utilizing strategies to promote adherence. Safer, more cost-effective, and more easily completed regimens are needed and should be combined with interventions to better identify, engage, and retain high-risk individuals across the cascade from diagnosis through treatment completion of LTBI.

Effectiveness of isoniazid preventative therapy in reducing incidence of active tuberculosis among people living with HIV/AIDS in public health facilities of Addis Ababa, Ethiopia: a historical cohort study

BACKGROUND

Human Immunodeficiency Virus (HIV) pandemic has exacerbated tuberculosis disease especially in Sub-Saharan African countries. The World Health Organization (WHO) and Joint United Nations Program on HIV/AIDS (UNAIDS) have recommended Isoniazid Preventive Therapy (IPT) for HIV infected patients to reduce the burden of tuberculosis (TB). Ethiopia has been implementing IPT since 2007. However, effectiveness of IPT in averting occurrence of active tuberculosis among HIV infected patients has not been assessed.

METHODS

Retrospective cohort study was employed using secondary data from public health institutions of Addis Ababa. Descriptive statistics and Generalized Linear Model based on Poisson regression was used for data analysis.

RESULTS

From 2524 HIV infected patients who were followed for 4106 Person-Years, a total of 277 incident Tuberculosis (TB) cases occurred. TB Incidence Rate was 0.21/100 Person-Year, 0.86/100 Person-Year & 7.18/100 Person-Year among IPT completed, in-completed and non-exposed patients, respectively. The adjusted Incidence Rate Ratio (aIRR) among IPT completed vs. non-exposed patients was 0.037 (95% CI, 0.016-0.072). Gender, residence area, employment status, baseline WHO stage of the disease (AIDS) and level of CD4 counts were identified as risk factors for TB incidence. The aIRR among patients who took Highly Active Anti- Retroviral Therapy (HAART) with IPT compared to those who took HAART alone was 0.063 (95% CI 0.035-0.104). IPT significantly reduced occurrence of active TB for 3 years.

CONCLUSIONS

IPT significantly reduced tuberculosis incidence by 96.3% compared to IPT non-exposed patients. Moreover concomitant use of HAART with IPT has shown a significant reduction in tuberculosis incidence by 93.7% than the use of HAART alone. Since IPT significantly protected occurrence of active TB for 3 years, its implementation should be further strengthened in the country.

Barriers in the implementation of isoniazid preventive therapy for people living with HIV in Northern Ethiopia: a mixed quantitative and qualitative study

BACKGROUND

Isoniazid preventive therapy is a key public health intervention for the prevention of tuberculosis disease among people living with HIV. Despite the confirmed efficacy of isoniazid preventive therapy and global recommendations existing for decades, its implementation remains limited. In resource constrained settings, few have investigated why isoniazid preventive therapy is not implemented on full scale. This study was designed to investigate the level of isoniazid preventive therapy implementation and reasons for suboptimal implementation in Tigray region of Ethiopia.

METHODS

A review of patient records combined with a qualitative study using in-depth interviews and focus group discussions was conducted in 11 hospitals providing isoniazid preventive therapy in the Tigray Region. The study participants were health providers working in the HIV clinics of the 11 hospitals in the province. Health providers were interviewed about their experience of providing isoniazid preventive therapy and challenges faced during its implementation. All conversations were audio-recorded. Record review of 16,443 HIV patients registered for care in these hospitals between September 2011 and April 2014 was done to determine isoniazid preventive therapy utilization. Data were collected from April to August 2014.

RESULTS

Fifty health providers participated in the study. Overall isoniazid preventive therapy coverage of the region was estimated to be 20 %. Isoniazid stock out, fear of creating isoniazid resistance, problems in patient acceptance, and lack of commitment of health managers to scale up the program were indicated by health providers as the main barriers hindering implementation of isoniazid preventive therapy.

CONCLUSION

Implementation of isoniazid preventive therapy in Tigray region of Ethiopia had low coverage. Frequent interruption of isoniazid supplies raises the concern of interrupted therapy resulting in creation of isoniazid resistance. Health managers, drug suppliers and partners working in HIV and tuberculosis programs should be committed to ensure an uninterrupted supply of isoniazid and full scale implementation of isoniazid preventive therapy to eligible people living with HIV.

Serological diagnosis of pulmonary Mycobacterium tuberculosis infection by LIPS using a multiple antigen mixture

Background

There is an urgent need for a simple and accurate test for the diagnosis of human Mycobacterium tuberculosis, the infectious agent causing tuberculosis (TB). Here we describe a serological test based on light emitting recombinant proteins for the diagnosis of pulmonary Mycobacterium tuberculosis infection.

Methods

Luciferase Immunoprecipitation Systems (LIPS), a fluid-phase immunoassay, was used to examine antibody responses against a panel of 24 different M. tuberculosis proteins. Three different strategies were used for generating the constructs expressing the recombinant fusion M. tuberculosis proteins with luciferase: synthetic gene synthesis, Gateway recombination cloning, and custom PCR synthesis. A pilot cohort of African pulmonary TB patients was used for initial antibody screening and confirmatory studies with selected antigens were performed with a cohort from Thailand and healthy US blood donors. In addition to testing M. tuberculosis antigens separately, a mixture that tested seven antigens simultaneously was evaluated for diagnostic performance.

Results

LIPS testing of a pilot set of serum samples from African pulmonary TB patients identified a potential subset of diagnostically useful M. tuberculosis antigens. Evaluation of a second independent cohort from Thailand validated highly significant antibody responses against seven antigens (PstS1, Rv0831c, FbpA, EspB, bfrB, HspX and ssb), which often showed robust antibody levels up to 50- to 1000-fold higher than local community controls. Marked heterogeneity of antibody responses was observed in the patients and the combined results demonstrated 73.5 % sensitivity and 100 % specificity for detection of pulmonary TB. A LIPS test simultaneously employing the seven M. tuberculosis antigen as a mixture matched the combined diagnostic performance of the separate tests, but showed an even higher diagnostic sensitivity (90 %) when a cut-off based on healthy US blood donors was used.

Conclusion

A LIPS immunoassay employing multiple M. tuberculosis antigens shows promise for the rapid and quantitative serological detection of pulmonary TB.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-015-0545-y) contains supplementary material, which is available to authorized users.

Effect of isoniazid preventive therapy on tuberculosis or death in persons with HIV: a retrospective cohort study

Background

Isoniazid preventive therapy (IPT) is a recommended strategy for prevention of tuberculosis (TB) in persons with Human Immunodeficiency Virus (HIV) although the benefits have not been unequivocally demonstrated in routine clinical practice with widespread ART adoption. Therefore, we assessed the effectiveness of IPT in prevention of TB or death in patients treated with antiretroviral therapy (ART) in a chronic care setting.

Methods

Retrospective cohort study of HIV patients enrolled in chronic care from 2007 to 2013. Eligible participants were HIV infected subjects (age > 15 years) with no (history of) TB. The combined effect of IPT and ART on the composite outcome (TB or death) was estimated using time-dependent Cox regression with adjustment for baseline covariates.

Results

1,922 patients were included, 374 (19.4 %) received IPT and 258 (13.4 %) developed TB or deceased. The median follow-up duration of the cohort was 839 days, with a total of 5491 person years. In unadjusted analysis, the combination of IPT and ART lowered the hazard of TB or death by 65 % [HR = 0.35; 95 % CI (0.16, 0.77)] compared to ART alone. Even after adjustment for confounders, the combined effect of ART and IPT resulted in a 60 % hazard reduction of TB or death in comparison to participants who received ART without IPT [HR = 0.40; 95 % CI (0.18, 0.87)]. The IPT-specific benefit in patients not receiving ART could not be reliably estimated due to high rates of ART adoption.

Conclusion

The combined effect of IPT and ART to prevent TB or death in HIV patients in a non-experimental setting in comparison to ART alone was estimated to be 60 %.

Optimizing the detection of recent tuberculosis infection in children in a high tuberculosis-HIV burden setting

RATIONALE

Children who are young, malnourished, and infected with HIV have significant risk of tuberculosis (TB) morbidity and mortality following TB infection. Treatment of TB infection is hindered by poor detection and limited pediatric data.

OBJECTIVES

Identify improved testing to detect pediatric TB infection.

METHODS

This was a prospective community-based study assessing use of the tuberculin skin test and IFN-γ release assays among children (n = 1,343; 6 mo to <15 yr) in TB-HIV high-burden settings; associations with child characteristics were measured.

MEASUREMENTS AND MAIN RESULTS

Contact tracing detects TB in 8% of child contacts within 3 months of exposure. Among children with no documented contact, tuberculin skin test and QuantiFERON-TB Gold In-Tube positivity was greater than T-SPOT.TB. Nearly 8% of children had IFN-γ release assay positive and skin test negative discordance. In a model accounting for confounders, all tests correlate with TB contact, but IFN-γ release assays correlate better than the tuberculin skin test (P = 0.0011). Indeterminate IFN-γ release assay results were not associated with age. Indeterminate QuantiFERON-TB Gold In-Tube results were more frequent in children infected with HIV (4.7%) than uninfected with HIV (1.9%), whereas T-SPOT.TB indeterminates were rare (0.2%) and not affected by HIV status. Conversion and reversion were not associated with HIV status. Among children infected with HIV, tests correlated less with contact as malnutrition worsened.

CONCLUSIONS

Where resources allow, use of IFN-γ release assays should be considered in children who are young, recently exposed, and infected with HIV because they may offer advantages compared with the tuberculin skin test for identifying TB infection, and improve targeted, cost-effective delivery of preventive therapy. Affordable tests of infection could dramatically impact global TB control.

Global epidemiology of tuberculosis

Despite the availability of effective chemotherapy, tuberculosis (TB) killed 1.3 million people in 2012. Alongside HIV, it remains a top cause of death from an infectious disease. Global targets for reductions in the epidemiological burden of TB have been set for 2015 and 2050 within the context of the Millennium Development Goals (MDGs) and by the Stop TB Partnership. Achieving these targets is the focus of national and international efforts in TB control, and showing whether or not they are achieved is of major importance to guide future and sustainable investments. This article provides a short overview of sources of data to estimate TB disease burden; presents estimates of TB incidence, prevalence, and mortality in 2012 and an assessment of progress toward the 2015 targets for reductions in these indicators based on trends since 1990 and projections up to 2015; analyzes trends in TB notifications and in the implementation of the Stop TB Strategy; and considers prospects for elimination of TB after 2015.

Common types of tuberculosis and co-infection with HIV at private health institutions in Ethiopia: a cross sectional study

BACKGROUND

Tuberculosis is a global emergency predominantly affecting developing countries. HIV has been the single most important reason for acquisition of tuberculosis for many patients. Conversely, tuberculosis can result in rapid progression of HIV disease. Ethiopia is a country affected seriously by HIV and tuberculosis. The main aim of this study is assessment of the types of tuberculosis and the extent of HIV infection among tuberculosis patients visiting private health institutions in Amhara region of Ethiopia.

METHODS

The study used a cross sectional method with data collected using well structured pretested questionnaires containing socio-demographic and clinical variables including HIV serostatus. The setting is tuberculosis treatment sites situated at 15 private health institutions in Amhara region.

RESULTS

A total of 1153 TB patients were included. The proportions of smear positive pulmonary TB, smear negative pulmonary TB, isolated extrapulmonary TB and disseminated TB cases were found to be 29.6%, 22.2%, 43.9% and 2.9%, respectively. TB lymphadenitis accounted for about 61% of the extrapulmonary cases followed by TB pleurisy (10.6%). Seventy percent of the patients had undergone HIV test, and 20% of them were HIV positive. Marital status, patient residence and type of TB are the major determinants of co-infection.

CONCLUSION

The occurrence of pulmonary tuberculosis is relatively low. Tuberculosis/HIV co-infection is also lower than other reports.

Therapy and prophylaxis of opportunistic infections in HIV-infected patients: a guideline by the German and Austrian AIDS societies (DAIG/ÖAG) (AWMF 055/066)

INTRODUCTION

There was a growing need for practical guidelines for the most common OIs in Germany and Austria under consideration of the local epidemiological conditions.

MATERIALS AND METHODS

The German and Austrian AIDS societies developed these guidelines between March 2010 and November 2011. A structured Medline research was performed for 12 diseases, namely Immune reconstitution inflammatory syndrome, Pneumocystis jiroveci pneumonia, cerebral toxoplasmosis, cytomegalovirus manifestations, candidiasis, herpes simplex virus infections, varizella zoster virus infections, progressive multifocal leucencephalopathy, cryptosporidiosis, cryptococcosis, nontuberculosis mycobacteria infections and tuberculosis. Due to the lack of evidence by randomized controlled trials, part of the guidelines reflects expert opinions. The German version was accepted by the German and Austrian AIDS Societies and was previously published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF; German Association of the Scientific Medical Societies).

CONCLUSION

The review presented here is a translation of a short version of the German-Austrian Guidelines of opportunistic infections in HIV patients. These guidelines are well-accepted in a clinical setting in both Germany and Austria. They lead to a similar treatment of a heterogeneous group of patients in these countries.

Prognostic significance of the interval between the initiation of antiretroviral therapy and the initiation of anti-tuberculosis treatment in HIV/tuberculosis-coinfected patients: results from the TREAT Asia HIV Observational Database

OBJECTIVES

We evaluated the effect of the time interval between the initiation of antiretroviral therapy (ART) and the initiation of tuberculosis (TB) treatment on clinical outcomes in HIV/TB-coinfected patients in an Asian regional cohort.

METHODS

Adult HIV/TB-coinfected patients in an observational HIV-infected cohort database who had a known date of ART initiation and a history of TB treatment were eligible for study inclusion. The time interval between the initiation of ART and the initiation of TB treatment was categorized as follows: TB diagnosed while on ART, ART initiated ≤ 90 days after initiation of TB treatment ('early ART'), ART initiated > 90 days after initiation of TB treatment ('delayed ART'), and ART not started. Outcomes were assessed using survival analyses.

RESULTS

A total of 768 HIV/TB-coinfected patients were included in this study. The median CD4 T-cell count at TB diagnosis was 100 [interquartile range (IQR) 40-208] cells/μL. Treatment outcomes were not significantly different between the groups with early ART and delayed ART initiation. Kaplan-Meier analysis indicated that mortality was highest for those diagnosed with TB while on ART (3.77 deaths per 100 person-years), and the prognoses of other groups were not different (in deaths per 100 person-years: 2.12 for early ART, 1.46 for delayed ART, and 2.94 for ART not started). In a multivariate model, the interval between ART initiation and TB therapy initiation did not significantly impact all-cause mortality.

CONCLUSIONS

A negative impact of delayed ART in patients coinfected with TB was not observed in this observational cohort of moderately to severely immunosuppressed patients. The broader impact of earlier ART initiation in actual clinical practice should be monitored more closely.

Fluoroquinolones for treating tuberculosis (presumed drug-sensitive)

BACKGROUND

Currently the World Health Organization only recommend fluoroquinolones for people with presumed drug-sensitive tuberculosis (TB) who cannot take standard first-line drugs. However, use of fluoroquinolones could shorten the length of treatment and improve other outcomes in these people. This review summarises the effects of fluoroquinolones in first-line regimens in people with presumed drug-sensitive TB.

OBJECTIVES

To assess fluoroquinolones as substitute or additional components in antituberculous drug regimens for drug-sensitive TB.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; CENTRAL (The Cochrane Library 2013, Issue 1); MEDLINE; EMBASE; LILACS; Science Citation Index; Databases of Russian Publications; and metaRegister of Controlled Trials up to 6 March 2013.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of antituberculous regimens based on rifampicin and pyrazinamide and containing fluoroquinolones in people with presumed drug-sensitive pulmonary TB.

DATA COLLECTION AND ANALYSIS

Two authors independently applied inclusion criteria, assessed the risk of bias in the trials, and extracted data. We used the risk ratio (RR) for dichotomous data and the fixed-effect model when it was appropriate to combine data and no heterogeneity was present. We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We identified five RCTs (1330 participants) that met the inclusion criteria. None of the included trials examined regimens of less than six months duration. Fluoroquinolones added to standard regimensA single trial (174 participants) added levofloxacin to the standard first-line regimen. Relapse and treatment failure were not reported. For death, sputum conversion, and adverse events we are uncertain if there is an effect (one trial, 174 participants, very low quality evidence for all three outcomes). Fluoroquinolones substituted for ethambutol in standard regimens Three trials (723 participants) substituted ethambutol with moxifloxacin, gatifloxacin, and ofloxacin into the standard first-line regimen. For relapse, we are uncertain if there is an effect (one trial, 170 participants, very low quality evidence). No trials reported on treatment failure. For death, sputum culture conversion at eight weeks, or serious adverse events we do not know if there was an effect (three trials, 723 participants, very low quality evidence for all three outcomes). Fluoroquinolones substituted for isoniazid in standard regimens A single trial (433 participants) substituted moxifloxacin for isoniazid. Treatment failure and relapse were not reported. For death, sputum culture conversion, or serious adverse events the substitution may have little or no difference (one trial, 433 participants, low quality evidence for all three outcomes). Fluoroquinolines in four month regimensSix trials are currently in progress testing shorter regimens with fluoroquinolones.

AUTHORS' CONCLUSIONS

Ofloxacin, levofloxacin, moxifloxacin, and gatifloxacin have been tested in RCTs of standard first-line regimens based on rifampicin and pyrazinamide for treating drug-sensitive TB. There is insufficient evidence to be clear whether addition or substitution of fluoroquinolones for ethambutol or isoniazid in the first-line regimen reduces death or relapse, or increases culture conversion at eight weeks. Much larger trials with fluoroquinolones in short course regimens of four months are currently in progress.

Tuberculosis-Associated Immune Reconstruction Inflammatory Syndrome (TB-IRIS) in HIV-Infected Patients: Report of Two Cases and the Literature Overview

We describe two HIV-infected patients with tuberculosis-associated immune reconstruction inflammatory syndrome (TB-IRIS): one with “paradoxical” IRIS and the other with “unmasking” IRIS. TB-IRIS in HIV-infected subjects is an exacerbation of the symptoms, signs, or radiological manifestations of a pathogenic antigen, related to recovery of the immune system after immunosuppression. We focused on the radiological characteristics of TB-IRIS and the briefly literature review on this syndrome.

Efficacy of a six-month versus a 36-month regimen for prevention of tuberculosis in HIV-infected persons in India: a randomized clinical trial

Background

The optimal duration of preventive therapy for tuberculosis (TB) among HIV-infected persons in TB-endemic countries is unknown.

Methods

An open-label randomized clinical trial was performed and analyzed for equivalence. Seven hundred and twelve HIV-infected, ART-naïve patients without active TB were randomized to receive either ethambutol 800 mg and isoniazid 300 mg daily for six-months (6EH) or isoniazid 300 mg daily for 36-months (36H). Drugs were dispensed fortnightly and adherence checked by home visits. Patients had chest radiograph, sputum smear and culture performed every six months, in addition to investigations if they developed symptoms. The primary endpoint was incident TB while secondary endpoints were all-cause mortality and adverse events. Survival analysis was performed on the modified intent to treat population (m-ITT) and rates compared.

Findings

Tuberculosis developed in 22 (6.4%) of 344 subjects in the 6EH arm and 13 (3.8%) of 339 subjects in the 36H arm with incidence rates of 2.4/100py (95%CI- 1.4–3.5) and 1.6/100py (95% CI-0.8–3.0) with an adjusted rate ratio (aIRR) of 1.6 (0.8–3.2). Among TST-positive subjects, the aIRR of 6EH was 1.7 (0.6–4.3) compared to 36H, p = 0.8. All-cause mortality and toxicity were similar in the two arms. Among 15 patients with confirmed TB, 4 isolates were resistant to isoniazid and 2 were multidrug-resistant.

Interpretation

Both regimens were similarly effective in preventing TB, when compared to historical incidence rates. However, there was a trend to lower TB incidence with 36H. There was no increase in isoniazid resistance compared to the expected rate in HIV-infected patients.

The trial is registered at ClinicalTrials.gov, NCT00351702.

Mortality in the year following antiretroviral therapy initiation in HIV-infected adults and children in Uganda and Zimbabwe

In low-income countries, children ≥4 years and adults with low CD4 count have equally high mortality risk in the 3 months after initiation of antiretroviral therapy, similar to that of untreated individuals. Bacterial infections play a major role; targeted interventions could have important benefits.

Background. Adult mortality in the first 3 months on antiretroviral therapy (ART) is higher in low-income than in high-income countries, with more similar mortality after 6 months. However, the specific patterns of changing risk and causes of death have rarely been investigated in adults, nor compared with children in low-income countries.

Methods. We used flexible parametric hazard models to investigate how mortality risks varied over the first year on ART in human immunodeficiency virus–infected adults (aged 18–73 years) and children (aged 4 months to 15 years) in 2 trials in Zimbabwe and Uganda.

Results. One hundred seventy-nine of 3316 (5.4%) adults and 39 of 1199 (3.3%) children died; half of adult/pediatric deaths occurred in the first 3 months. Mortality variation over year 1 was similar; at all CD4 counts/CD4%, mortality risk was greatest between days 30 and 50, declined rapidly to day 180, then declined more slowly. One-year mortality after initiating ART with 0–49, 50–99 or ≥100 CD4 cells/μL was 9.4%, 4.5%, and 2.9%, respectively, in adults, and 10.1%, 4.4%, and 1.3%, respectively, in children aged 4–15 years. Mortality in children aged 4 months to 3 years initiating ART in equivalent CD4% strata was also similar (0%–4%: 9.1%; 5%–9%: 4.5%; ≥10%: 2.8%). Only 10 of 179 (6%) adult deaths and 1 of 39 (3%) child deaths were probably medication-related. The most common cause of death was septicemia/meningitis in adults (20%, median 76 days) and children (36%, median 79 days); pneumonia also commonly caused child deaths (28%, median 41 days).

Conclusions. Children ≥4 years and adults with low CD4 values have remarkably similar, and high, mortality risks in the first 3 months after ART initiation in low-income countries, similar to cohorts of untreated individuals. Bacterial infections are a major cause of death in both adults and children; targeted interventions could have important benefits.

High prevalence of drug resistance amongst HIV-exposed and -infected children in a tuberculosis prevention trial

An emergence of drug-resistant tuberculosis (DR-TB) in settings affected by human immunodeficiency virus (HIV) and tuberculosis (TB) has been observed. We investigated the prevalence of DR-TB in P1041, a multicentered, randomised, double-blind trial which compared the administration of isoniazid (INH) to placebo, in HIV-exposed, non-infected and -infected African infants in the absence of any documented TB exposure. The prevalence of multidrug-resistant TB (MDR-TB) was 22.2% (95%CI 8.5-45.8) and INH monoresistance 5.6% (95%CI 0.1-27.6) among culture-confirmed cases, with all MDR-TB occurring in a single site. There was no association between INH treatment or placebo group, or between HIV infection status, and DR-TB prevalence. There was a high prevalence of DR-TB among HIV-exposed and -infected children. Surveillance of DR-TB among children in high-burden TB-HIV settings should be routine.

Latent and subclinical tuberculosis in HIV infected patients: a cross-sectional study

BACKGROUND

HIV and tuberculosis (TB) are commonly associated. Identifying latent and asymptomatic tuberculosis infection in HIV-positive patients is important in preventing death and morbidity associated with active TB.

METHODS

Cross-sectional study of one time use of an interferon-gamma release assay (T-SPOT.TB - immunospot) to detect tuberculosis infection in patients in a UK inner city HIV clinic with a large sub-Saharan population.

RESULTS

542 patient samples from 520 patients who disclosed their symptoms of TB were tested. Median follow-up was 35 months (range 27-69). More than half (55%) originated from countries with medium or high tuberculosis burden and 57% were women. Antiretroviral therapy was used by 67%; median CD4 count at test was 458 cells/μl. A negative test was found in 452 samples and an indeterminate results in 40 (7.4%) but neither were associated with a low CD4 count. A positive test was found in 10% (50/502) individuals. All patients with positive tests were referred to the TB specialist, 47 (94%) had a chest radiograph and 46 (92%) attended the TB clinic. Two had culture-positive TB and a third individual with features of active TB was treated. 40 started and 38 completed preventive treatment. One patient who completed preventive treatment with isoniazid monotherapy subsequently developed isoniazid-resistant pulmonary tuberculosis. No patient with a negative test has developed TB.

CONCLUSIONS

We found an overall prevalence of latent TB infection of 10% through screening for TB in those with HIV infection and without symptoms, and a further 1% with active disease, a yield greater than typically found in contact tracing. Acceptability of preventive treatment was high with 85% of those with latent TB infection eventually completing their TB chemotherapy regimens. IGRA-based TB screening among HIV-infected individuals was feasible in the clinical setting and assisted with appropriate management (including preventive treatment and therapy for active disease). Follow-up of TB incidence in this group is needed to assess the long-term effects of preventive treatment.

Predictive value of interferon-γ release assays for incident active tuberculosis: a systematic review and meta-analysis

BACKGROUND

We aimed to assess whether interferon-γ release assays (IGRAs) can predict the development of active tuberculosis and whether the predictive ability of these tests is better than that of the tuberculin skin test (TST).

METHODS

Longitudinal studies of the predictive value for active tuberculosis of in-house or commercial IGRAs were identified through searches of PubMed, Embase, Biosis, and Web of Science and complementary manual searches up to June 30, 2011. Eligible studies included adults or children, with or without HIV, who were free of active tuberculosis at study baseline. We summarised incidence rates in forest plots and pooled data with random-effects models when appropriate. We calculated incidence rate ratios (IRR) for rates of disease progression in IGRA-positive versus IGRA-negative individuals.

FINDINGS

15 studies had a combined sample size of 26 680 participants. Incidence of tuberculosis during a median follow-up of 4 years (IQR 2-6), even in IGRA-positive individuals, was 4-48 cases per 1000 person-years. Seven studies with no possibility of incorporation bias and reporting baseline stratification on the basis of IGRA results showed a moderate association between positive results and subsequent tuberculosis (pooled unadjusted IRR 2·10, 95% CI 1·42-3·08). Compared with test-negative results, IGRA-positive and TST-positive results were much the same with regard to the risk of tuberculosis (pooled IRR in the five studies that used both was 2·11 [95% CI 1·29-3·46] for IGRA vs 1·60 [0·94-2·72] for TST at the 10 mm cutoff). However, the proportion of IGRA-positive individuals in seven of 11 studies that assessed both IGRAs and TST was generally lower than TST-positive individuals.

INTERPRETATION

Neither IGRAs nor the TST have high accuracy for the prediction of active tuberculosis, although use of IGRAs in some populations might reduce the number of people considered for preventive treatment. Until more predictive biomarkers are identified, existing tests for latent tuberculosis infection should be chosen on the basis of relative specificity in different populations, logistics, cost, and patients' preferences rather than on predictive ability alone.

FUNDING

Special Programme for Research and Training in Tropical Diseases (WHO), Wellcome Trust, Canadian Institutes of Health Research, UK Medical Research Council, and the European and Developing Countries Clinical Trials Partnership.

Tuberculosis in HIV programmes in lower-income countries: practices and risk factors

BACKGROUND

Tuberculosis (TB) is a common diagnosis in human immunodeficiency virus (HIV) infected patients on antiretroviral treatment (ART).

OBJECTIVE

To describe TB-related practices in ART programmes in lower-income countries and identify risk factors for TB in the first year of ART.

METHODS

Programme characteristics were assessed using standardised electronic questionnaire. Patient data from 2003 to 2008 were analysed and incidence rate ratios (IRRs) calculated using Poisson regression models.

RESULTS

Fifteen ART programmes in 12 countries in Africa, South America and Asia were included. Chest X-ray, sputum microscopy and culture were available free of charge in respectively 13 (86.7%), 14 (93.3%) and eight (53.3%) programmes. Eight sites (53.3%) used directly observed treatment and five (33.3%) routinely administered isoniazid preventive treatment (IPT). A total of 19 413 patients aged ≥ 16 years contributed 13,227 person-years of follow-up; 1081 new TB events were diagnosed. Risk factors included CD4 cell count (>350 cells/μl vs. <25 cells/μl, adjusted IRR 0.46, 95%CI 0.33-0.64, P < 0.0001), sex (women vs. men, adjusted IRR 0.77, 95%CI 0.68-0.88, P = 0.0001) and use of IPT (IRR 0.24, 95%CI 0.19-0.31, P < 0.0001).

CONCLUSIONS

Diagnostic capacity and practices vary widely across ART programmes. IPT prevented TB, but was used in few programmes. More efforts are needed to reduce the burden of TB in HIV co-infected patients in lower income countries.

An evaluation of factors associated with taking and responding positive to the tuberculin skin test in individuals with HIV/AIDS

BACKGROUND

The tuberculin skin test (TST) is still the standard test for detecting latent infection by M tuberculosis (LTBI). Given that the Brazilian Health Ministry recommends that the treatment of latent tuberculosis (LTBI) should be guided by the TST results, the present study sets out to describe the coverage of administering the TST in people living with HIV at two referral health centers in the city of Recife, where TST is offered to all patients. In addition, factors associated with the non-application of the test and with positive TST results were also analyzed.

METHODS

A cross-sectional study was carried out with HIV patients, aged 18 years or over, attending outpatient clinics at the Correia Picanço Hospital/SES/PE and the Oswaldo Cruz/UPE University Hospital, who had been recommended to take the TST, in the period between November 2007 and February 2010. Univariate and multivariate logistic regression analyses were carried out to establish associations between the dependent variable - taking the TST (yes/no), at a first stage analysis, and the independent variables, followed by a second stage analysis considering a positive TST as the dependent variable. The odds ratio was calculated as the measure of association and the confidence interval (CI) at 95% as the measure of accuracy of the estimate.

RESULTS

Of the 2,290 patients recruited, 1087 (47.5%) took the TST. Of the 1,087 patients who took the tuberculin skin test, the prevalence of TST ≥ 5 mm was 21.6% among patients with CD4 ≥ 200 and 9.49% among those with CD4 < 200 (p = 0.002). The patients most likely not to take the test were: men, people aged under 39 years, people with low educational levels and crack users. The risk for not taking the TST was statiscally different for health service. Patients who presented better immunity (CD4 ≥ 200) were more than two and a half times more likely to test positive that those with higher levels of immunodeficiency (CD4 < 200).

CONCLUSIONS

Considering that the TST is recommended by the Brazilian health authorities, coverage for taking the test was very low. The most serious implication of this is that LTBI treatment was not carried out for the unidentified TST-positive patients, who may consequently go on to develop TB and eventually die.

Costs and consequences of additional chest x-ray in a tuberculosis prevention program in Botswana

RATIONALE

Isoniazid preventive therapy is effective in reducing the risk of tuberculosis (TB) in persons living with HIV (PLWH); however, screening must exclude TB disease before initiating therapy. Symptom screening alone may be insufficient to exclude TB disease in PLWH because some PLWH with TB disease have no symptoms. The addition of chest radiography (CXR) may improve disease detection.

OBJECTIVES

The objective of the present analysis was to compare the costs and effects of the addition of CXR to the symptom screening process against the costs and effects of symptom screening alone.

METHODS

Using data from Botswana, a decision analytic model was used to compare a "Symptom only" policy against a "Symptom+CXR" policy. The outcomes of interest were cost, death, and isoniazid- and multidrug-resistant TB in a hypothetical cohort of 10,000 PLWH.

MEASUREMENTS AND MAIN RESULTS

The Symptom+CXR policy prevented 16 isoniazid- and 0.3 multidrug-resistant TB cases; however, because of attrition from the screening process, there were 98 excess cases of TB, 15 excess deaths, and an additional cost of U.S. $127,100. The Symptom+CXR policy reduced deaths only if attrition was close to zero; however, to eliminate attrition the cost would be U.S. $2.8 million per death averted. These findings did not change in best- and worst-case scenario analyses.

CONCLUSIONS

In Botswana, a policy with symptom screening only preceding isoniazid-preventive therapy initiation prevents more TB and TB-related deaths, and uses fewer resources, than a policy that uses both CXR and symptom screening.

Translating evidence into policy in low-income countries: lessons from co-trimoxazole preventive therapy

In the April 2010 issue of this journal, Date et al. expressed concern over the slow scale-up in low-income settings of two therapies for the prevention of opportunistic infections in people living with the human immunodeficiency virus: co-trimoxazole prophylaxis and isoniazid preventive therapy. This short paper discusses the important ways in which policy analysis can be of use in understanding and explaining how and why certain evidence makes its way into policy and practice and what local factors influence this process. Key lessons about policy development are drawn from the research evidence on co-trimoxazole prophylaxis, as such lessons may prove helpful to those who seek to influence the development of national policy on isoniazid preventive therapy and other treatments. Researchers are encouraged to disseminate their findings in a manner that is clear, but they must also pay attention to how structural, institutional and political factors shape policy development and implementation. Doing so will help them to understand and address the concerns raised by Date et al. and other experts. Mainstreaming policy analysis approaches that explain how local factors shape the uptake of research evidence can provide an additional tool for researchers who feel frustrated because their research findings have not made their way into policy and practice.

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.

Timing of antiretroviral therapy for HIV in the setting of TB treatment

The convergent human immunodeficiency virus (HIV) and tuberculosis (TB) pandemics continue to collectively exact significant morbidity and mortality worldwide. Highly active antiretroviral therapy (HAART) has been a critical component in combating the scourge of these two conditions as both a preemptive and therapeutic modality. However, concomitant administration of antiretroviral and antituberculous therapies poses significant challenges, including cumulative drug toxicities, drug-drug interactions, high pill burden, and the immune reconstitution inflammatory syndrome (IRIS), thus complicating the management of coinfected individuals. This paper will review data from recent studies regarding the optimal timing of HAART initiation relative to TB treatment, with the ultimate goal of improving coinfection-related morbidity and mortality while mitigating toxicity resulting from concurrent treatment of both infections.

Latent tuberculosis detection by interferon γ release assay during pregnancy predicts active tuberculosis and mortality in human immunodeficiency virus type 1-infected women and their children

BACKGROUND

We evaluated the prognostic usefulness of interferon γ release assays (IGRAs) for active tuberculosis and mortality in Kenyan human immunodeficiency virus type 1 (HIV-1)-infected women and their infants.

METHODS

Prevalence and correlates of Mycobacterium tuberculosis-specific T-SPOT.TB IGRA positivity were determined during pregnancy in a historical cohort of HIV-1-infected women. Hazard ratios, adjusted for baseline maternal CD4 cell count (aHR(CD4)), were calculated for associations between IGRA positivity and risk of active tuberculosis and mortality over 2-year postpartum follow-up among women and their infants.

RESULTS

Of 333 women tested, 52 (15.6%) had indeterminate IGRA results. Of the remaining 281 women, 120 (42.7%) had positive IGRA results, which were associated with a 4.5-fold increased risk of active tuberculosis (aHR(CD4), 4.5; 95% confidence interval [CI], 1.1-18.0; P = .030). For immunosuppressed women (CD4 cell count, <250 cells/μL), positive IGRA results were associated with increased risk of maternal mortality (aHR(CD4), 3.5; 95% CI, 1.02-12.1;), maternal active tuberculosis or mortality (aHR(CD4), 5.2; 95% CI, 1.7-15.6; P = .004), and infant active tuberculosis or mortality overall (aHR(CD4), 3.0; 95% CI, 1.0-8.9; P = .05) and among HIV-1-exposed uninfected infants (aHR(CD4), 7.3; 95% CI, 1.6-33.5; P = .01).

CONCLUSIONS

Positive IGRA results for HIV-1-infected pregnant women were associated with postpartum active tuberculosis and mortality among mothers and their infants.

Association of isoniazid preventive therapy with lower early mortality in individuals on antiretroviral therapy in a workplace programme

OBJECTIVE

To describe the association between isoniazid preventive therapy (IPT) and mortality among individuals starting antiretroviral therapy (ART) in a workplace programme in South Africa where tuberculosis (TB) incidence is very high.

METHODS

ART-naive individuals starting ART from January 2004 to December 2007 were followed for up to 12 months. Deaths were ascertained from clinic and human resource data. The association between IPT and mortality was assessed using Cox regression.

RESULTS

A total of 3270 individuals were included (median age 45; 93% men; median baseline CD4 cell count 155 cells/μl (interquartile range 87-221); and 45% with WHO stage 3/4]. Nine hundred twenty-two (28%) individuals started IPT either prior to or within 3 months of starting ART. Individuals who started IPT tended to have less advanced HIV disease at ART initiation. Two hundred fifty-nine (7.9%) deaths were observed with overall mortality rate 8.9 per 100 person-years [95% confidence interval (CI) 7.9-10.6]. The unadjusted mortality rate was lower among those who received IPT compared with those who did not [3.7/100 vs. 11.1/100 person-years, respectively, hazard ratio 0.34 (95% CI 0.24-0.49)]; this association remained after adjustment for age, baseline CD4 cell count, baseline WHO stage, year of ART start, and individual company (hazard ratio 0.51, 95% CI 0.32-0.80). In sensitivity analyses restricted to those with no previous history of TB (n = 3036) or with no TB symptoms at ART initiation (n = 2251), IPT remained associated with reduced mortality [adjusted hazard ratios 0.51 (95% CI 0.32-0.81) and 0.48 (95% CI 0.24-0.96), respectively].

CONCLUSION

Mortality was lower among individuals receiving IPT with or prior to ART start. These results support routine use of IPT in conjunction with ART.

Eligibility for and outcome of treatment of latent tuberculosis infection in a cohort of HIV-infected people in Spain

BACKGROUND

Previous studies have demonstrated the efficacy of treatment for latent tuberculosis infection (TLTBI) in persons infected with the human immunodeficiency virus, but few studies have investigated the operational aspects of implementing TLTBI in the co-infected population.The study objectives were to describe eligibility for TLTBI as well as treatment prescription, initiation and completion in an HIV-infected Spanish cohort and to investigate factors associated with treatment completion.

METHODS

Subjects were prospectively identified between 2000 and 2003 at ten HIV hospital-based clinics in Spain. Data were obtained from clinical records. Associations were measured using the odds ratio (OR) and its 95% confidence interval (95% CI).

RESULTS

A total of 1242 subjects were recruited and 846 (68.1%) were evaluated for TLTBI. Of these, 181 (21.4%) were eligible for TLTBI either because they were tuberculin skin test (TST) positive (121) or because their TST was negative/unknown but they were known contacts of a TB case or had impaired immunity (60). Of the patients eligible for TLTBI, 122 (67.4%) initiated TLTBI: 99 (81.1%) were treated with isoniazid for 6, 9 or 12 months; and 23 (18.9%) with short-course regimens including rifampin plus isoniazid and/or pyrazinamide. In total, 70 patients (57.4%) completed treatment, 39 (32.0%) defaulted, 7 (5.7%) interrupted treatment due to adverse effects, 2 developed TB, 2 died, and 2 moved away. Treatment completion was associated with having acquired HIV infection through heterosexual sex as compared to intravenous drug use (OR:4.6; 95% CI:1.4-14.7) and with having taken rifampin and pyrazinamide for 2 months as compared to isoniazid for 9 months (OR:8.3; 95% CI:2.7-24.9).

CONCLUSIONS

A minority of HIV-infected patients eligible for TLTBI actually starts and completes a course of treatment. Obstacles to successful implementation of this intervention need to be addressed.

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.

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.

[Consensus document on the diagnosis, treatment and prevention of tuberculosis]

Pulmonary TB should be suspected in patients with respiratory symptoms longer than 2-3 weeks. Immunosuppression may modify clinical and radiological presentation. Chest X-ray shows very suggestive, albeit sometimes atypical, signs of TB. Complex radiological tests (CT scan, MR) are more useful in extrapulmonary TB. At least 3 serial representative samples of the clinical location are used for diagnosis whenever possible. Bacilloscopy and liquid medium cultures are indicated in all cases. Genetic amplification techniques are coadjuvant in moderate or high TB suspicion. Administration of isoniazid, rifampicin, ethambutol and pyrazinamide (HREZ) for 2 months and HR for 4 additional months is recommended in new cases of TB, except in cases of meningitis in which treatment should continue for up to 12 months and up to 9 months in spinal TB with neurological involvement, and in silicosis. Appropriate adjustments with antiretroviral treatment should be made in HIV patients. Combined therapy is recommended to avoid development of resistance. An antibiogram to first line drugs should be performed in all the initial isolations of new patients. Treatment control is one of the most important activities in TB management. The Tuberculin Skin Test (TST) is positive in TB infection when >or=5mm, and Interferon-Gamma Release Assays (IGRA) are recommended in combination with TT. The standard treatment schedule for infection is 6 months with isoniazid. In pulmonary TB, respiratory isolation is applied for 3 weeks or until 3 negative bacilloscopy samples are obtained.

Isoniazid-associated hepatitis and antiretroviral drugs during tuberculosis prophylaxis in hiv-infected adults in Botswana

RATIONALE

Little is known about the incidence of isoniazid-associated hepatitis in HIV-infected Africans who receive both isoniazid preventive therapy (IPT) and antiretroviral therapy (ART).

OBJECTIVES

To assess the rate of and risk factors for isoniazid (INH)-associated hepatitis in persons living with HIV (PLWH) during IPT.

METHODS

PLWH recruited for a clinical trial received 6 months of open-label, daily, self-administered INH at public health clinics. At screening PLWH were excluded if they had any cough, weight loss, night sweats, or other illness. Alcohol abuse was defined as meeting any CAGE criterion. INH-associated hepatitis (INH-hepatitis) was defined as having either alanine or aspartate aminotransferase greater than 5.0 times the upper limit of normal regardless of symptoms when INH was not excluded as the cause.

MEASUREMENTS AND MAIN RESULTS

Of 1,995 PLWH enrolled between 2004 and 2006, 1,762 adhered to at least 4 months of IPT and were analyzed. Nineteen (1.1%) developed hepatitis probably or possibly associated with INH including one death at month 6; 14 of 19 (74%) occurred in months 1-3. Antiretroviral therapy (ART) was received by 480 participants but was not statistically associated with INH-hepatitis (relative risk [RR], 1.56; 95% confidence intervals [CI], 0.62-3.9); those receiving nevirapine had a higher rate (2.0%) than those receiving efavirenz (0.9%; P = 0.34). Although alcohol use did not reach significance (RR, 1.42; 95% CI, 0.57-3.51), meeting at least one CAGE criterion approached statistical significance (RR, 2.37; 95% CI, 0.96-5.84). Neither age greater than 35 years nor the presence of hepatitis B virus core antibody was associated with INH-hepatitis.

CONCLUSIONS

The observed rates of INH-hepatitis were similar to published data. Six months of IPT, which is recommended by the World Health Organization, was relatively safe in this, the largest cohort of African PLWH. Clinical trial registered with www.clinicaltrials.gov (NCT 00164281).

Microscopic observation drug susceptibility assay for tuberculosis screening before isoniazid preventive therapy in HIV-infected persons

BACKGROUND

Active tuberculosis (TB) must be excluded before initiating isoniazid preventive therapy (IPT) in persons infected with human immunodeficiency virus (HIV), but currently used screening strategies have poor sensitivity and specificity and high patient attrition rates. Liquid TB culture is now recommended for the detection of Mycobacterium tuberculosis in individuals suspected of having TB. This study compared the efficacy, effectiveness, and speed of the microscopic observation drug susceptibility (MODS) assay with currently used strategies for TB screening before IPT in HIV-infected persons.

METHODS

A total of 471 HIV-infected IPT candidates at 3 hospitals in Lima, Peru, were enrolled in a prospective comparison of TB screening strategies, including laboratory, clinical, and radiographic assessments.

RESULTS

Of 435 patients who provided 2 sputum samples, M. tuberculosis was detected in 27 (6.2%) by MODS culture, 22 (5.1%) by Lowenstein-Jensen culture, and 7 (1.6%) by smear. Of patients with any positive microbiological test result, a MODS culture was positive in 96% by 14 days and 100% by 21 days. The MODS culture simultaneously detected multidrug-resistant TB in 2 patients. Screening strategies involving combinations of clinical assessment, chest radiograph, and sputum smear were less effective than 2 liquid TB cultures in accurately diagnosing and excluding TB (P<.01). Screening strategies that included nonculture tests had poor sensitivity and specificity.

CONCLUSIONS

MODS culture identified and reliably excluded cases of pulmonary TB more accurately than other screening strategies, while providing results significantly faster than Lowenstein-Jensen culture. Streamlining of the ruling out of TB through the use of liquid culture-based strategies could help facilitate the massive up-scaling of IPT required to reduce HIV and TB morbidity and mortality.

Treatment of latent tuberculosis infection in HIV infected persons

BACKGROUND

Individuals with human immunodeficiency virus (HIV) infection are at an increased risk of developing active tuberculosis (TB). It is known that treatment of latent TB infection (LTBI), also referred to as TB preventive therapy or chemoprophylaxis, helps to prevent progression to active disease in HIV negative populations. However, the extent and magnitude of protection (if any) associated with preventive therapy in those infected with HIV should be quantified. This present study is an update of the original review.

OBJECTIVES

To determine the effectiveness of TB preventive therapy in reducing the risk of active tuberculosis and death in HIV-infected persons.

SEARCH STRATEGY

This review was updated using the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, AIDSLINE, AIDSTRIALS, AIDSearch, NLM Gateway and AIDSDRUGS (publication date from 01 July 2002 to 04 April 2008). We also scanned reference lists of articles and contacted authors and other researchers in the field in an attempt to identify additional studies that may be eligible for inclusion in this review.

SELECTION CRITERIA

We included randomized controlled trials in which HIV positive individuals were randomly allocated to TB preventive therapy or placebo, or to alternative TB preventive therapy regimens. Participants could be tuberculin skin test positive or negative, but without active tuberculosis.

DATA COLLECTION AND ANALYSIS

Three reviewers independently applied the study selection criteria, assessed study quality and extracted data. Effects were assessed using relative risk for dichotomous data and mean differences for continuous data.

MAIN RESULTS

12 trials were included with a total of 8578 randomized participants. TB preventive therapy (any anti-TB drug) versus placebo was associated with a lower incidence of active TB (RR 0.68, 95% CI 0.54 to 0.85). This benefit was more pronounced in individuals with a positive tuberculin skin test (RR 0.38, 95% CI 0.25 to 0.57) than in those who had a negative test (RR 0.89, 95% CI 0.64 to 1.24). Efficacy was similar for all regimens (regardless of drug type, frequency or duration of treatment). However, compared to INH monotherapy, short-course multi-drug regimens were much more likely to require discontinuation of treatment due to adverse effects. Although there was reduction in mortality with INH monotherapy versus placebo among individuals with a positive tuberculin skin test (RR 0.74, 95% CI 0.55 to 1.00) and with INH plus rifampicin versus placebo regardless of tuberculin skin test status (RR 0.69, 95% CI 0.50 to 0.95), overall, there was no evidence that TB preventive therapy versus placebo reduced all-cause mortality (RR 0.94, 95% CI 0.85 to 1.05).

AUTHORS' CONCLUSIONS

Treatment of latent tuberculosis infection reduces the risk of active TB in HIV positive individuals especially in those with a positive tuberculin skin test. The choice of regimen will depend on factors such as availability, cost, adverse effects, adherence and drug resistance. Future studies should assess these aspects. In addition, trials evaluating the long-term effects of anti-tuberculosis chemoprophylaxis, the optimal duration of TB preventive therapy, the influence of level of immunocompromise on effectiveness and combination of anti-tuberculosis chemoprophylaxis with antiretroviral therapy are needed.

Strategies to reduce early morbidity and mortality in adults receiving antiretroviral therapy in resource-limited settings

PURPOSE OF REVIEW

We review recently published literature concerning early morbidity and mortality during antiretroviral therapy (ART) among patients in resource-limited settings. We focus on articles providing insights into this burden of disease and strategies to address it.

RECENT FINDINGS

In sub-Saharan Africa, mortality rates during the first year of ART are very high (8-26%), with most deaths occurring in the first few months. This figure compares with 3-13% in programmes in Latin America and the Caribbean and 11-13% in south-east Asia. Risk factors generally reflect late presentation with advanced symptomatic disease. Key causes of morbidity and mortality include tuberculosis (TB), acute sepsis, cryptococcal meningitis, malignancy and wasting syndrome/chronic diarrhoea. Current literature shows that the fundamental need is for much earlier HIV diagnosis and initiation of ART. In addition, further studies provide data on the role of screening and prophylaxis against opportunistic diseases (particularly TB, bacterial sepsis and cryptococcal disease) and the management of specific opportunistic diseases and complications of ART. Effective and sustainable delivery of these interventions requires strengthening of programmes.

SUMMARY

Strategies to address this disease burden should include earlier HIV diagnosis and ART initiation, screening and prophylaxis for opportunistic infections, optimized management of specific diseases and treatment complications, and programme strengthening.

Short-course therapy with daily rifapentine in a murine model of latent tuberculosis infection

RATIONALE

Regimens recommended to treat latent tuberculosis infection (LTBI) are 3 to 9 months long. A 2-month rifampin+pyrazinamide regimen is no longer recommended. Shorter regimens are highly desirable. Because substituting rifapentine for rifampin in the standard regimen for active tuberculosis halves the treatment duration needed to prevent relapse in mice, we hypothesized daily rifapentine-based regimens could shorten LTBI treatment to 2 months or less.

OBJECTIVES

To improve an existing model of LTBI chemotherapy and evaluate the efficacy of daily rifapentine-based regimens.

METHODS

Mice were immunized with a more immunogenic recombinant Bacille Calmette-Guérin strain (rBCG30) and received very low-dose aerosol infection with Mycobacterium tuberculosis to establish a stable lung bacterial burden below 10(4) CFU without drug treatment. Mice received a control (isoniazid alone, rifampin alone, rifampin+isoniazid, rifampin+pyrazinamide) or test (rifapentine alone, rifapentine+isoniazid, rifapentine+pyrazinamide, rifapentine+isoniazid+pyrazinamide) regimen for 8 weeks. Rifamycin doses were 10 mg/kg/d, analogous to the same human doses. Outcomes were biweekly lung CFU counts and relapse after 4 to 8 weeks of treatment.

MEASUREMENTS AND MAIN RESULTS

M. tuberculosis CFU counts remained stable around 3.65 log(10) in immunized, untreated mice. Isoniazid or rifampin left all or most mice culture-positive at week 8. Rifampin+isoniazid cured 0 and 53% of mice and rifampin+pyrazinamide cured 47 and 100% of mice in 4 and 8 weeks, respectively. Rifapentine-based regimens were more active than rifampin+isoniazid and indistinguishable from rifampin+pyrazinamide.

CONCLUSIONS

In this improved murine model of LTBI chemotherapy with very low lung burden, existing regimens were well represented. Daily rifapentine-based regimens were at least as active as rifampin+pyrazinamide, suggesting they could effectively treat LTBI in 6 to 8 weeks.

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.

Implementation of co-trimoxazole prophylaxis and isoniazid preventive therapy for people living with HIV

OBJECTIVE

To measure progress in implementing co-trimoxazole prophylaxis (CTXp) (trimethoprim plus sulfamethoxazole) and isoniazid preventive therapy (IPT) policy recommendations, identify barriers to the development of national policies and pinpoint challenges to implementation.

METHODS

In 2007 we conducted by e-mail a cross-sectional survey of World Health Organization (WHO) HIV/AIDS programme officers in 69 selected countries having a high burden of infection with HIV or HIV-associated tuberculosis (TB). The specially-designed, self-administered questionnaire contained items covering national policies for CTXp and IPT in people living with HIV, current level of implementation and barriers to developing or implementing these policies.

FINDINGS

The 41 (59%) respondent countries, representing all WHO regions, comprised 85% of the global burden of HIV-associated TB and 82% of the global burden of HIV infection. Thirty-eight countries (93%) had an established national policy for CTXp, but only 66% of them (25/38) had achieved nationwide implementation. For IPT, 21 of 41 countries (51%) had a national policy but only 28% of them (6/21) had achieved nationwide implementation. Despite significant progress in the development of CTXp policy, the limited availability of co-trimoxazole for this indication and inadequate systems to manage drug supply impeded nationwide implementation. Inadequate intensified tuberculosis case-finding and concerns regarding isoniazid resistance were challenges to the development and implementation of national IPT policies.

CONCLUSION

Despite progress in implementing WHO-recommended CTXp and IPT policies, these interventions remain underused. Urgent steps are required to facilitate the development and implementation of these policies.

HIV infection and tuberculosis in South Africa: an urgent need to escalate the public health response

One of the greatest challenges facing post-apartheid South Africa is the control of the concomitant HIV and tuberculosis epidemics. HIV continues to spread relentlessly, and tuberculosis has been declared a national emergency. In 2007, South Africa, with 0.7% of the world's population, had 17% of the global burden of HIV infection, and one of the world's worst tuberculosis epidemics, compounded by rising drug resistance and HIV co-infection. Until recently, the South African Government's response to these diseases has been marked by denial, lack of political will, and poor implementation of policies and programmes. Nonetheless, there have been notable achievements in disease management, including substantial improvements in access to condoms, expansion of tuberculosis control efforts, and scale-up of free antiretroviral therapy (ART). Care for acutely ill AIDS patients and long-term provision of ART are two issues that dominate medical practice and the health-care system. Decisive action is needed to implement evidence-based priorities for the control of the HIV and tuberculosis epidemics. By use of the framework of the Strategic Plans for South Africa for tuberculosis and HIV/AIDS, we provide prioritised four-step approaches for tuberculosis control, HIV prevention, and HIV treatment. Strong leadership, political will, social mobilisation, adequate human and financial resources, and sustainable development of health-care services are needed for successful implementation of these approaches.