Enhanced tuberculosis identification through 1-month follow-up of smear-negative tuberculosis suspects

Prevalence and incidence of symptomatic pulmonary tuberculosis based on repeated population screening in a district in Ethiopia: a prospective cohort study

OBJECTIVE

In Ethiopia, one-third of the estimated tuberculosis cases are not detected or reported. Incidence estimates are inaccurate and rarely measured directly. Assessing the 'real' incidence under programme conditions is useful to understand the situation. This study aimed to measure the prevalence and incidence of symptomatic pulmonary tuberculosis (PTB) during 1 year in the adult population of Dale in Ethiopia.

DESIGN

A prospective population-based cohort study.

SETTING

Every household in Dale was visited three times at 4-month intervals.

PARTICIPANTS

Individuals aged ≥15 years.

OUTCOME MEASURES

Microscopy smear positive PTB (PTB s+), bacteriologically confirmed PTB (PTB b+) by microscopy, GeneXpert, or culture and clinically diagnosed PTB (PTB c+).

RESULTS

Among 136 181 individuals, 2052 had presumptive TB (persistent cough for 14 days or more with or without haemoptysis, weight loss, fever, night sweats, chest pain or difficulty breathing), in the first round of household visits including 93 with PTB s+, 98 with PTB b+ and 24 with PTB c+; adding those with PTB who were already on treatment, the total number of PTB was 201, and the prevalence was 147 (95% CI: 127 to 168)/100 000 population. Out of all patients with PTB, the proportion detected by symptom screening was in PTB s+ 65%, PTB b+ 67% and PTB c+44%. During 96 388 person-years follow-up, 1909 had presumptive TB, 320 had PTB and the total incidence of PTB was 332 (95% CI: 297 to 370)/100 000 person-years, while the incidence of PTB s+, PTB b+ and PTB c+ was 230 (95% CI: 201 to 262), 263 (95% CI: 232 to 297) and 68 (95% CI: 53 to 86)/100 000 person-years, respectively.

CONCLUSION

The prevalence of symptomatic sputum smear-positive TB was still high, only one-third of prevalent PTB cases notified and the incidence rate highest in the age group 25-34 years, indicating ongoing transmission. Finding missing people with TB through repeated symptom screening can contribute to reducing transmission.

Tuberculosis and Migrant Pathways in an Urban Setting: A Mixed-Method Case Study on a Treatment Centre in the Lisbon Metropolitan Area, Portugal

Tuberculosis (TB) is an infectious disease associated with poverty. In the European Union TB tends to concentrate in urban settings. In Lisbon, previous studies revealed, the presence of migrant populations from a high endemic country, is one of the risk factors contributing to TB. To better understand TB in foreign-born individuals in the Lisbon Metropolitan Area, a mixed-method case study was undertaken on a TB treatment centre in a high-risk part of urban Portugal. Quantitatively, annual TB cases were analysed from 2008 to 2018, dividing foreign-origin cases into recent migrants and long-term migrants. Qualitatively, we explored recent migrants’ reasons, experiences and perceptions associated with the disease. Our results showed that foreign-born individuals accounted for 45.7% of cases, mainly originated from Angola, Guinea-Bissau, and Cabo Verde. TB in recent migrants increased over the years for Angola and Guinea-Bissau, while for Cabo Verde TB cases were due to migrants residing in Portugal for more than 2 years. Recent migrants’ reasons to travel to Portugal were to study, to live and work, tourism, and seeking better healthcare. Visiting family and friends, historical links and common language were key drivers for the choice of country. Recent migrants and long-term migrants may present distinct background profiles associated with diagnosed TB.

Hypertension is associated with increased mortality in patients with tuberculosis in Guinea-Bissau

OBJECTIVES

Tuberculosis (TB) is associated with a number of non-communicable co-morbidities, which can complicate treatment and impair outcome. The aim of this study was to assess the impact of hypertension on disease severity, treatment outcome and survival in a cohort of patients with TB.

METHODS

A retrospective cohort study was conducted in Guinea-Bissau. Patients newly diagnosed with TB between November 2003 and June 2016 were included. Hypertension was defined as blood pressure ≥140/90 mmHg. Disease severity was assessed using the Bandim TBscore. Survival was assessed at the end of treatment and 2 years after treatment initiation.

RESULTS

In total, 1544 patients were included in this study. Hypertension was present in 12.8% of patients at inclusion. Patients with hypertension had slightly less severe TB, but were less likely to have a successful treatment outcome and had 64% higher mortality at 2-year follow-up (adjusted hazard ratio 1.64, 95% confidence interval 1.15-2.34). Mortality rates were highest in hypertensive female patients and patients aged ≥ 45 years.

CONCLUSION

Patients with high blood pressure at the start of TB treatment had a higher mortality rate at 2-year follow-up. Mortality rates were highest in hypertensive females and patients aged ≥ 45 years.

Diabetes in urban Guinea-Bissau; patient characteristics, mortality and prevalence of undiagnosed dysglycemia

Background

The burden of diabetes mellitus in Sub-Saharan Africa is growing rapidly, and yet the prevalence and patient characteristics are still largely unknown.

Objectives

We analyzed clinical and demographic characteristics of Type 2 diabetes (T2DM) patients attending a diabetes clinic in Guinea-Bissau from February 2008 to April 2014, and estimated the prevalence and risk factors of unknown-impaired fasting plasma glucose (FPG) and diabetes, as well as excess mortality associated with T2DM.

Methods

We characterized T2DM patients attending the national diabetes clinic in Bissau. Diabetes was diagnosed based on FPG. We matched T2DM patients 1:1 with non-diabetes community controls on age and sex to determine relevant risk factors for T2DM using logistic regression. Furthermore, we matched patients 1:6 with community controls to assess long-term survival (until February 2019) in a Cox regression using calendar time as the underlying timescale. Verbal autopsies determined the cause of death among T2DM patients and controls.

Results

The mean age among T2DM was 50.6 (SD 11.1), and the mean FPG at first consultation was high (13.2 mmol/L (SD 5.1)). Ethnicity, family history of diabetes, hypertension, and anthropometrics differed among T2DM patients, community controls with impaired FPG, and healthy controls. Family history of diabetes (OR = 5.65, 95% CI: 3.10–10.3) and elevated waist circumference (2.33, 1.26–4.29) were significant risk factors for T2DM. 20.4% (59/289) of community controls had abnormal FPG. T2DM patients had an excess mortality hazard ratio of 3.53 (95%CI: 1.92–6.52). Deaths caused by bacterial infections, including foot ulcers, were more common among T2DM patients, compared with community controls (54% (7/13) vs. 19% (5/27) (P = 0.02)).

Conclusion

Several risk factors including were associated with T2DM in Guinea-Bissau. We found a high prevalence of elevated FPG among randomly selected community controls. In combination with higher mortality among T2DM patients, an urgent need for better treatment options and increased awareness.

HIV testing uptake and HIV positivity among presumptive tuberculosis patients in Mandalay, Myanmar, 2014-2017

Introduction

The World Health Organization’s framework for TB/HIV collaborative activities recommends provider-initiated HIV testing and counselling (PITC) of patients with presumptive TB. In Myanmar, PITC among presumptive TB patients was started at the TB outpatient department (TB OPD) in Mandalay in 2014. In this study, we assessed the uptake of PITC among presumptive TB patients and the number needed to screen to find one additional HIV positive case, stratified by demographic and clinical characteristics.

Method

This was a cross-sectional study using routinely collected data of presumptive TB patients who registered for PITC services at the TB OPD between August 2014 and December 2017 in Mandalay.

Result

Among 21,989 presumptive TB patients registered, 9,796 (44.5%) had known HIV status at registration and 2,763 (28.2%) were people already living with HIV (PLHIV). Of the remainder, 85.3% (10,401/12,193) were newly tested for HIV. Patients <55 years old, those registered in 2014, 2015 and 2017, those employed and those having a history of TB contact had higher uptakes of HIV testing. Among 10,401 patients tested for HIV, 213 (2.1%) patients were newly diagnosed with HIV and this included 147 (69.0%) who were not diagnosed as having TB. The overall prevalence of HIV (previously known and newly diagnosed) among presumptive TB patients was 14.8% (2,976/20,119). The number needed to screen to find one additional HIV case was 48: this number was lower (i.e., a higher yield) among patients aged 35–44 years and among those who were divorced or separated.

Conclusion

Uptake of HIV testing among eligible presumptive TB patients was high with four out of five presumptive TB patients being tested for HIV. This strategy detected many additional HIV-positive persons, and this included those who were not diagnosed with TB. We strongly recommend that this strategy be implemented nationwide in Myanmar.

A clinical score has utility in tuberculosis case-finding among patients with HIV: A feasibility study from Bissau

BACKGROUND

Clinical scores are promising case-finding tools for tuberculosis (TB) among HIV-infected patients. The Bandim TBscore has been shown to increase the diagnostic yield among patients with presumed TB in general, but has not previously been tested among newly diagnosed HIV patients at high risk of TB.

METHODS

HIV-infected patients were included in this cross-sectional study. A pre-post-intervention study design was used to assess the outcome of a change in practice, i.e. the application of a clinical score (TBscore) consisting of 13 signs and symptoms to assess the need for further TB diagnostics. Patients with a TBscore ≥2 were evaluated using smear microscopy and Xpert MTB/RIF. A TB diagnosis was made based on microbiology or clinical evaluation. The sensitivity and specificity of the TBscore were compared with those of World Health Organization symptoms.

RESULTS

The TB prevalence among newly enrolled HIV-infected patients during the study period was 13.4% (22/164). Using the TBscore and a diagnostic algorithm, it was possible to increase the proportion of patients started on TB treatment from 2.7% (10/367) the year before the study to 10.4% (17/164) during the study period. Five patients diagnosed with TB were not started on TB treatment as they were lost to follow-up or died. With a cut-off value of 2, the TBscore had a sensitivity, specificity, positive predictive value, and negative predictive value of 95.5% (21/22), 36.9% (41/111), 23.1% (22/118), and 97.6% (41/42), respectively.

CONCLUSION

The TBscore is useful for standardized TB screening among HIV-infected individuals and may be a valuable tool to prioritize patients at high risk of TB.

HIV care among patients with presumptive tuberculosis in Masvingo district of Zimbabwe, 2017: how well are we doing?

INTRODUCTION

While HIV care among tuberculosis (TB) patients is successfully implemented and monitored, it is not routinely reported among "presumptive TB patients without TB". The present study describes the ascertainment of HIV status and receipt of antiretroviral therapy (ART) and the associated factors among presumptive TB patients (with and without TB) in 35 public health facilities of Masvingo district of Zimbabwe from January to June 2017.

METHODS

This was an analysis of secondary programme data. We performed log binomial regression to calculate adjusted relative risks (aRR) and 95% confidence intervals (CI).

RESULTS

Of 1369 presumptive TB patients, 1181 (86%) were ascertained for HIV status (98% among those subsequently diagnosed with TB, 83% among non-TB). Of them, 748 (63%) were HIV positive, more among TB patients (69%) than those without TB (61%). Among HIV-positive patients, 475 (64%) received ART, significantly higher among TB patients (78%) compared to those without TB (57%). Patients without TB were significantly more likely to have non-ascertained for HIV status (aRR=2.4, 95% CI=1.4-5.0) and not receiving ART (aRR=1.8, 95% CI=1.6-2.0), compared to those with TB.

CONCLUSION

We found high rates of HIV status ascertainment among presumptive TB patients. But, ART uptake was poor among "presumptive TB patients without TB", despite implementation of "test and treat" strategy in Zimbabwe. The programme should step up the monitoring of HIV status and ART receipt among presumptive TB patients, by introducing an indicator in the quarterly reports of the national TB programme.

HIV Testing among Patients with Presumptive Tuberculosis: How Do We Implement in a Routine Programmatic Setting? Results of a Large Operational Research from India

Background

In March 2012, World Health Organization recommended that HIV testing should be offered to all patients with presumptive TB (previously called TB suspects). How this is best implemented and monitored in routine health care settings in India was not known. An operational research was conducted in Karnataka State (South India, population 64 million, accounts for 10% of India’s HIV burden), to test processes and learn results and challenges of screening presumptive TB patients for HIV within routine health care settings.

Methods

In this cross-sectional study conducted between January-March 2012, all presumptive TB patients attending public sector sputum microscopy centres state-wide were offered HIV testing by the laboratory technician, and referred to the nearest public sector HIV counselling and testing services, usually within the same facility. The HIV status of the patients was recorded in the routine TB laboratory form and TB laboratory register. The laboratory register was compiled to obtain the number of presumptive TB patients whose HIV status was ascertained, and the number found HIV positive. Aggregate data on reasons for non-testing were compiled at district level.

Results

Overall, 115,308 patients with presumptive TB were examined for sputum smear microscopy at 645 microscopy centres state-wide. Of these, HIV status was ascertained for 62,847(55%) among whom 7,559(12%) were HIV-positive, and of these, 3,034(40%) were newly diagnosed. Reasons for non-testing were reported for 37,700(72%) of the 52,461 patients without HIV testing; non-availability of testing services at site of sputum collection was cited by health staff in 54% of respondents. Only 4% of patients opted out of HIV testing.

Conclusion

Offering HIV testing routinely to presumptive TB patients detected large numbers of previously-undetected instances of HIV infection. Several operational challenges were noted which provide useful lessons for improving uptake of HIV testing in this important group.

Tuberculosis elimination in the post Millennium Development Goals era

The Millennium Development Goal for tuberculosis (TB) is to stop the increase in incidence and halve the mortality of TB between 1990 and 2015. This goal has now been reached on a global scale, although not in the most affected region of Africa. The new target is TB elimination, defined as one case of active TB per one million population per year, which is to be reached before 2050. This review will discuss the main tools in play, namely case-finding and new diagnostics, increased access and effectiveness of anti-TB therapy (directly observed therapy, short course (DOTS)), preventive therapy for latent infection, and vaccination. Each approach is discussed and a way forward in research and management is suggested.

HIV-infected presumptive tuberculosis patients without tuberculosis: How many are eligible for antiretroviral therapy in Karnataka, India?

For certain subgroups within people living with the human immunodeficiency virus (HIV) [active tuberculosis (TB), pregnant women, children <5 years old, and serodiscordant couples], the World Health Organization recommends antiretroviral therapy (ART) irrespective of CD4 count. Another subgroup which has received increased attention is “HIV-infected presumptive TB patients without TB”. In this study, we assess the proportion of HIV-infected presumptive TB patients eligible for ART in Karnataka State (population 60 million), India. This was a cross-sectional analysis of data of HIV-infected presumptive TB patients diagnosed in May 2015 abstracted from national TB and HIV program records. Of 42,585 presumptive TB patients, 28,964 (68%) were tested for HIV and 2262 (8%) were HIV positive. Of the latter, 377 (17%) had active TB. Of 1885 “presumptive TB patients without active TB”, 1100 (58%) were already receiving ART. Of the remaining 785 who were not receiving ART, 617 (79%) were assessed for ART eligibility and of those, 548 (89%) were eligible for ART. About 90% of “HIV-infected presumptive TB patients without TB” were eligible for ART. This evidence supports a public health approach of starting all “HIV-infected presumptive TB patients without TB” on ART irrespective of CD4 count in line with global thinking about ‘test and treat’.

Are HIV-positive presumptive tuberculosis patients without tuberculosis getting the care they need in Zimbabwe?

SETTING

Emakhandeni Clinic provides decentralised and integrated tuberculosis (TB) and human immunodeficiency virus (HIV) care in Bulawayo, Zimbabwe.

OBJECTIVES

To compare HIV care for presumptive TB patients with and without TB registered in 2013.

DESIGN

Retrospective cohort study using routine programme data.

RESULTS

Of 422 registered presumptive TB patients, 26% were already known to be HIV-positive. Among the remaining 315 patients, 255 (81%) were tested for HIV, of whom 190 (75%) tested HIV-positive. Of these, 26% were diagnosed with TB and 71% without TB (3% had no TB result recorded). For the 134 patients without TB, antiretroviral treatment (ART) eligibility data were recorded for 42 (31%); 95% of these were ART eligible. Initiation of cotrimoxazole preventive therapy (CPT) and ART was recorded for respectively 88% and 90% of HIV-positive patients with TB compared with respectively 40% and 38% of HIV-positive patients without TB (P < 0.001).

CONCLUSION

Presumptive TB patients without TB had a high HIV positivity rate and, for those with available data, most were ART eligible. Unlike HIV-positive patients diagnosed with TB, CPT and ART uptake for these patients was poor. A 'test and treat' approach and better service linkages could be life-saving for these patients, especially in southern Africa, where there are high burdens of HIV and TB.

Diagnostic management and outcomes of pulmonary tuberculosis suspects admitted to a central hospital in Malawi

SETTING

Zomba Central Hospital, Malawi.

OBJECTIVE

To determine diagnostic management and outcomes of pulmonary tuberculosis (PTB) suspects admitted to adult wards.

DESIGN

A retrospective, cross-sectional review of medical records of patients admitted to hospital between July and September 2010.

RESULTS

There were 141 PTB suspects. Sputum examination was requested and performed in 67 (48%) suspects, but none were smear-positive. Chest X-ray (CXR) was requested and performed in 26 (39%) suspects whose sputum smears were negative. Eleven suspects had a CXR suggestive of PTB: two were started on TB treatment and eight died before treatment started. Human immunodeficiency virus (HIV) status was known for 50 patients (35% of all suspects) on admission, all of whom were HIV-positive. HIV testing was requested for 37 patients, but was only performed in 12, five of whom were HIV-positive. Only one patient was referred for antiretroviral treatment. There were 41 (29%) deaths, eight of whom had probable TB and were not treated. In the remaining 33 patients who died, only nine (27%) had sputum smears examined and four (12%) had a CXR.

CONCLUSION

The study shows inadequacies in the diagnostic management of PTB suspects in the Zomba Central Hospital, but suggests opportunities for improvement.

Decline in overall, smear-negative and HIV-positive TB incidence while smear-positive incidence stays stable in Guinea-Bissau 2004-2011

OBJECTIVE

To calculate Tuberculosis (TB) incidence rates in Guinea-Bissau over an 8-year period.

METHODS

Since 2003, a surveillance system has registered all TB cases in six suburban districts of Bissau. In this population-based prospective follow-up study, 1205 cases of pulmonary TB were identified between January 2004 and December 2011. Incidence rates were calculated using census data from the Bandim Health and Demographic Surveillance System (HDSS).

RESULTS

The overall incidence of pulmonary TB was 279 per 100,000 person-years of observation; the male incidence being 385, and the female 191. TB incidence rates increased significantly with age in both sexes, regardless of smear or HIV status. Despite a peak with unknown cause of 352 per 100,000 in 2007, the overall incidence of pulmonary TB declined over the period. The incidence of HIV infected TB cases declined significantly from 108 to 39 per 100,000, while the incidence of smear-positive TB cases remained stable; the overall figure was 188 per 100,000.

CONCLUSIONS

Overall incidence of pulmonary TB in Guinea-Bissau has declined from 2004 to 2011. The decline was also seen in the subgroups of smear-negative and HIV-positive TB cases, probably due to antiretroviral treatment. Smear-positive TB incidence remains stable over the period.

Treatment delay affects clinical severity of tuberculosis: a longitudinal cohort study

OBJECTIVES

To describe the risk factors for treatment delay and the effect of delay on the severity of tuberculosis (TB) in a prospectively followed TB cohort at the Bandim Health Project in Guinea-Bissau.

BACKGROUND

Treatment delay in patients with TB is associated with increased mortality and transmission of disease. However, it is not well described whether delay influences clinical severity at diagnosis. Previously reported risk factors for treatment delay vary in different geographical and cultural settings. Such information has never been investigated in our setting. Change in delay over time is rarely reported and our prospectively followed TB cohort gives an opportunity to present such data.

PARTICIPANTS

Patients were included at the time of diagnosis at three local TB clinics and the national TB reference hospital. Inclusion criteria were age >15 years and diagnosis of TB by either sputum examination or by the WHO clinical criteria. Patients with extrapulmonary TB were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was treatment delay. Delay was assessed by patient questionnaires. The secondary outcome was Bandim TBscore as a measure of TB morbidity and all-cause mortality.

RESULTS

A total of 1424 persons were diagnosed with TB in the study area between 2003 and 2010. We included 973 patients with TB in the study. The median treatment delay was 12.1 weeks. Risk factors for delay were low educational level, HIV-1+HIV-2 dual infection and negative sputum smear. TB treatment delay decreased by 10.3% (7.9-12.6%) per year during the study period. Delay was significantly associated with clinical severity at presentation with 20.8% severe TB cases in the low delay quartile compared with 33.9% if delay was over the median of 12.1 weeks.

CONCLUSIONS

Long treatment delay was associated with more severe clinical presentation. Treatment delay in TB cases is decreasing in Guinea-Bissau.

High mortality in adults hospitalized for active tuberculosis in a low HIV prevalence setting

BACKGROUND

This study aims to evaluate the outcomes of adults hospitalized for tuberculosis in a higher-income region with low HIV prevalence.

METHODS

A retrospective cohort study was conducted on all adults hospitalized for pulmonary and/or extrapulmonary tuberculosis in an acute-care hospital in Hong Kong during a two-year period. Microscopy and solid-medium culture were routinely performed. The diagnosis of tuberculosis was made by: (1) positive culture of M. tuberculosis, (2) positive M. tuberculosis PCR result, (3) histology findings of tuberculosis infection, and/or (4) typical clinico-radiological manifestations of tuberculosis which resolved after anti-TB treatment, in the absence of alternative diagnoses. Time to treatment ('early', started during initial admission; 'late', subsequent periods), reasons for delay, and short- and long-term survival were analyzed.

RESULTS

Altogether 349 patients were studied [median(IQR) age 62(48-77) years; non-HIV immunocompromised conditions 36.7%; HIV/AIDS 2.0%]. 57.9%, 16.3%, and 25.8% had pulmonary, extrapulmonary, and pulmonary-extrapulmonary tuberculosis respectively. 58.2% was smear-negative; 0.6% multidrug-resistant. 43.4% developed hypoxemia. Crude 90-day and 1-year all-cause mortality was 13.8% and 24.1% respectively. 57.6% and 35.8% received 'early' and 'late' treatment respectively, latter mostly culture-guided [median(IQR) intervals, 5(3-9) vs. 43(25-61) days]. Diagnosis was unknown before death in 6.6%. Smear-negativity, malignancy, chronic lung diseases, and prior exposure to fluoroquinolones (adjusted-OR 10.6, 95%CI 1.3-85.2) delayed diagnosis of tuberculosis. Failure to receive 'early' treatment independently predicted higher mortality (Cox-model, adjusted-HR 1.8, 95%CI 1.1-3.0).

CONCLUSIONS

Mortality of hospitalized tuberculosis patients is high. Newer approaches incorporating methods for rapid diagnosis and initiation of anti-tuberculous treatment are urgently required to improve outcomes.

HIV prevalence among persons suspected of tuberculosis: policy implications for India

BACKGROUND

HIV testing of persons referred for tuberculosis diagnosis (TB suspects) is recommended by World Health Organization but is not a policy in India, where HIV prevalence among TB suspects has never been reported. The current Indian policy of offering HIV testing only to TB cases may limit opportunities for early HIV diagnosis and treatment.

METHODS

All adult TB suspects examined for diagnostic sputum microscopy in Mandya district (2 million population), in December 2010, were offered voluntary HIV counseling and testing. Participants were assessed for subsequent TB diagnosis.

RESULTS

Of 1668 eligible TB suspects, HIV status was ascertained for 1539 (92%). Among these, 108 (7%) were HIV positive. Of the 108, 43 (40%) were newly diagnosed as HIV (ie, not previously known to have HIV infection). To detect a new case of HIV infection, the number needed to screen among TB patients was 13, as compared to an number needed to screen of 37 among "TB suspects not diagnosed as TB". Applied annually in 2010, HIV testing of TB suspects in 2010 could have identified approximately 534 newly diagnosed HIV cases, a 51% increase in district HIV case finding.

CONCLUSIONS

Routine HIV testing of TB suspects was feasible and yielded a large number of HIV cases in absolute terms and would increase district HIV case finding by 51%. The number of patients needed to be HIV tested to find a previously undetected HIV case among TB suspects was greater than for TB cases but was potentially acceptable. Given heterogeneity of HIV epidemic in India, broader surveillance is required before national policy decision.

HIV and tuberculosis--science and implementation to turn the tide and reduce deaths

INTRODUCTION

Every year, HIV-associated tuberculosis (TB) deprives 350,000 mainly young people of productive and healthy lives.People die because TB is not diagnosed and treated in those with known HIV infection and HIV infection is not diagnosed in those with TB. Even in those in whom both HIV and TB are diagnosed and treated, this often happens far too late. These deficiencies can be addressed through the application of new scientific evidence and diagnostic tools.

DISCUSSION

A strategy of starting antiretroviral therapy (ART) early in the course of HIV infection has the potential to considerably reduce both individual and community burden of TB and needs urgent evaluation for efficacy, feasibility and broader social and economic impact. Isoniazid preventive therapy can reduce the risk of TB and, if given strategically in addition to ART, provides synergistic benefit. Intensified TB screening as part of the "Three I's" strategy should be conducted at every clinic, home or community-based attendance using a symptoms-based algorithm, and new diagnostic tools should increasingly be used to confirm or refute TB diagnoses. Until such time when more sensitive and specific TB diagnostic assays are widely available, bolder approaches such as empirical anti-TB treatment need to be considered and evaluated. Patients with suspected or diagnosed TB must be screened for HIV and given cotrimoxazole preventive therapy and ART if HIV-positive. Three large randomized trials provide conclusive evidence that ART initiated within two to four weeks of start of anti-TB treatment saves lives, particularly in those with severe immunosuppression. The key to ensuring that these collaborative activities are delivered is the co-location and integration of TB and HIV services within the health system and the community.

CONCLUSIONS

Progress towards reducing HIV-associated TB deaths can be achieved through attention to simple and deliverable actions on the ground.

Improving the prevention, diagnosis and treatment of TB among people living with HIV: the role of operational research

Operational research is necessary to improve the access to and delivery of tuberculosis prevention, diagnosis and treatment interventions for people living with HIV. We conducted an extensive review of the literature and reports from recent expert consultations and research-related meetings organized by the World Health Organization and the Stop TB Partnership to identify a TB/HIV operational research agenda. We present critical operational research questions in a series of key areas: optimizing TB prevention by enhancing the uptake of isoniazid preventive therapy and the implementation of infection control measures; assessing the effectiveness of existing diagnostic tools and scaling up new technologies; improving service delivery models; and reducing risk factors for mortality among TB patients living with HIV. We discuss the potential impact that addressing the operational research questions may have on improving programmes' performance, assessing new strategies or interventions for TB control, or informing global or national policy formulation. Financial resources to implement these operational research questions should be mobilized from existing and new funding mechanisms. National TB and HIV/AIDS programmes should develop their operational research agendas based on these questions, and conduct the research that they consider crucial for improving TB and HIV control in their settings in collaboration with research stakeholders.

Factors associated with negative direct sputum examination in Asian and African HIV-infected patients with tuberculosis (ANRS 1260)

Objective

To identify factors associated with negative direct sputum examination among African and Cambodian patients co-infected by Mycobacterium tuberculosis and HIV.

Design

Prospective multicenter study (ANRS1260) conducted in Cambodia, Senegal and Central African Republic.

Methods

Univariate and multivariate analyses (logistic regression) were used to identify clinical and radiological features associated with negative direct sputum examination in HIV-infected patients with positive M. tuberculosis culture on Lowenstein-Jensen medium.

Results

Between September 2002 and December 2005, 175 co-infected patients were hospitalized with at least one respiratory symptom and pulmonary radiographic anomaly. Acid-fast bacillus (AFB) examination was positive in sputum samples from 110 subjects (63%) and negative in 65 patients (37%). Most patients were at an advanced stage of HIV disease (92% at stage III or IV of the WHO classification) with a median CD4 cell count of 36/mm³. In this context, we found that sputum AFB negativity was more frequent in co-infected subjects with associated respiratory tract infections (OR = 2.8 [95%CI:1.1–7.0]), dyspnea (OR = 2.5 [95%CI:1.1–5.6]), and localized interstitial opacities (OR = 3.1 [95%CI:1.3–7.6]), but was less frequent with CD4≤50/mm³ (OR = 0.4 [95%CI:0.2–0.90), adenopathies (OR = 0.4 [95%CI:0.2–0.93]) and cavitation (OR = 0.1 [95%CI:0.03–0.6]).

Conclusions

One novel finding of this study is the association between concomitant respiratory tract infection and negative sputum AFB, particularly in Cambodia. This finding suggests that repeating AFB testing in AFB-negative patients should be conducted when broad spectrum antibiotic treatment does not lead to complete recovery from respiratory symptoms. In HIV-infected patients with a CD4 cell count below 50/mm3 without an identified cause of pneumonia, systematic AFB direct sputum examination is justified because of atypical clinical features (without cavitation) and high pulmonary mycobacterial burden.