Changes in the incidence of tuberculosis in a cohort of HIV-seroconverters before and after the introduction of HAART

Environmental Factors Related to Pulmonary Tuberculosis in HIV-Infected Patients in the Combined Antiretroviral Therapy (cART) Era

The aim of our study was to evaluate the seasonal variations and whether short-term exposure to environmental risk factors, such as climate and air pollution, is associated with PTB-related hospital admissions in human immunodeficiency virus (HIV)-infected patients in Spain during the era of combined antiretroviral therapy (cART). A retrospective study was carried out using data from the Minimum Basic Data Set (MBDS) and the State Meteorological Agency (AEMET) of Spain. The primary outcome variable was hospital admissions with PTB diagnosis. The environmental risk factors evaluated were season, temperature, humidity, NO2, SO2, O3, PM10, and CO. Overall, HIV-infected patients had a lower frequency of PTB-related hospital admissions in summer (22.8%) and autumn (22.4%), but higher values in winter (26.6%) and spring (28.2%). Using a Bayesian temporal model, PTB-related hospital admissions were less frequent in summer-autumn and more abundant in winter-spring during the first years of follow-up. During the later years of follow-up, the seasonal trends continued resulting in the lowest values in autumn and the highest in spring. When considering short-term exposure to environmental risk factors, lower temperatures at 1 week (odds ratio (OR) = 1.03; p = 0.008), 1.5 weeks (OR = 1.03; p<0.001), 2 weeks (OR = 1.04; p<0.001), and 3 weeks (OR = 1.03; p<0.001) prior to PTB admission. In addition, higher concentration of NO2 at the time of admission were significantly associated with higher likelihoods of PTB-related hospital admission in HIV-infected patients when 1.5 weeks (OR = 1.1; p = 0.044) and 2 weeks (OR = 1.21; p<0.001) were used as controls. Finally, higher concentration of SO2 at 1.5 weeks prior to PTB admission was significantly associated with a higher likelihood of PTB-related hospital admissions (OR = 0.92; p = 0.029). In conclusion, our data suggest an apparent seasonal variation in hospital admissions of HIV-infected patients with a PTB diagnosis (summer/autumn vs. winter/spring), as well as a link to short-term exposure to environmental risk factors, such as temperature and ambient NO2 and SO2.

Implementation and Operational Research: Declining Tuberculosis Incidence Among People Receiving HIV Care and Treatment Services in East Africa, 2007-2012

BACKGROUND

Antiretroviral therapy (ART) reduces the risk of Tuberculosis (TB) among people living with HIV (PLWH). With ART scale-up in sub-Saharan Africa over the past decade, incidence of TB among PLWH engaged in HIV care is predicted to decline.

METHODS

We conducted a retrospective analysis of routine clinical data from 168,330 PLWH receiving care at 35 facilities in Kenya, Tanzania, and Uganda during 2003-2012, participating in the East African region of the International Epidemiologic Databases to Evaluate AIDS. Temporal trends in facility-based annual TB incidence rates (per 100,000 person years) among PLWH and country-specific standardized TB incidence ratios using annual population-level TB incidence data from the World Health Organization were computed between 2007 and 2012. We examined patient-level and facility-level factors associated with incident TB using multivariable Cox models.

RESULTS

Overall, TB incidence rates among PLWH in care declined 5-fold between 2007 and 2012 from 5960 to 985 per 100,000 person years [P = 0.0003] (Kenya: 7552 to 1115 [P = 0.0007]; Tanzania: 7153 to 635 [P = 0.0025]; Uganda: 3204 to 242 [P = 0.018]). Standardized TB incidence ratios significantly decreased in the 3 countries, indicating a narrowing gap between incidence rates among PLWH and the general population. We observed lower hazards of incident TB among PLWH on ART and/or isoniazid preventive therapy and receiving care in facilities offering TB treatment onsite.

CONCLUSIONS

Annual TB incidence rates among PLWH significantly declined during ART scale-up but remained higher than the general population. Increasing access to ART and isoniazid preventive therapy and co-location of HIV and TB treatment may further reduce TB incidence among PLWH.

Isoniazid Prophylactic Therapy for the Prevention of Tuberculosis in HIV Infected Adults: A Systematic Review and Meta-Analysis of Randomized Trials

Background

Infection with Human Immunodeficiency virus (HIV) is an important risk factor for Tuberculosis (TB). Anti-Retroviral Therapy (ART) has improved the prognosis of HIV and reduced the risk of TB infected patients. Isoniazid Preventive Therapy (IPT) aims to reduce the development of active TB in patients with latent TB.

Objective

Systematically review and synthesize effect estimates of IPT for TB prevention in adult HIV patients. Secondary objectives were to assess the effect of IPT on HIV disease progression, all-cause mortality and adverse drug reaction (ADR).

Search Strategy

Electronic databases were searched to identify relevant articles in English available by September 11^th 2015.

Selection Criteria

Research articles comparing IPT to placebo or no treatment in HIV infected adults using randomized clinical trials.

Data Analysis

A qualitative review included study-level information on randomization and treatment allocation. Effect estimates were pooled using random-effects models to account for between-study heterogeneity.

Main Results

This review assessed ten randomized clinical trials that assigned 7619 HIV patients to IPT or placebo. An overall 35% of TB risk reduction (RR = 0.65, 95% CI (0.51, 0.84)) was found in all participants, however, larger benefit of IPT was observed in Tuberculin Skin Test (TST) positive participants, with pooled relative risk reduction of 52% [RR = 0.48; 95% CI (0.29, 0.82)] and with a prediction interval ranging from 0.13 to 1.81. There was no statistically significant effect of IPT on TB occurrence in TST negative or unknown participants. IPT also reduced the risk of HIV disease progression in all participants (RR = 0.69; 95% CI (0.48, 0.99)) despite no benefits observed in TST strata. All-cause mortality was not affected by IPT although participants who had 12 months of IPT tend to have a reduced risk (RR = 0.65; 95% CI(0.47, 0.90)). IPT had an elevated, yet statistically non-significant, risk of adverse drug reaction [RR = 1.20; 95% CI (1.20, 1.71)]. Only a single study assessed the effect of IPT in combination with ART in preventing TB and occurrence of multi-drug resistant tuberculosis.

Conclusions

IPT use substantially contributes in preventing TB in persons with HIV in general and in TST positive individuals in particular. More evidence is needed to explain discrepancies in the protective effect of IPT in these individuals.

Impact of antiretroviral therapy on opportunistic infections of HIV-infected children in the therapeutic research, education and AIDS training asia pediatric HIV observational database

BACKGROUND

There are limited data on opportunistic infections (OIs) and factors associated with their occurrence after highly active antiretroviral therapy (HAART) in Asian children. The use of HAART in Asia started much later than in developed countries and therefore reported findings may not be fully applicable to the pediatric HIV epidemic in Asia.

METHODS

Retrospective and prospectively collected data from the Therapeutic Research, Education and AIDS Training Asia Pediatric HIV Observational Database cohort study from March 1993 to March 2009 were analyzed. OIs were defined according to World Health Organization clinical staging criteria and incidence rates calculated. Factors associated with the incidence of severe OIs were analyzed using random effects Poisson regression modeling.

RESULTS

Of 2280 children in the cohort, 1752 were ever reported to have received antiretroviral therapy, of whom 1480 (84%) started on HAART. Before commencing any antiretroviral therapy, OIs occurred at a rate of 89.5 per 100 person-years. The incidence rate was 28.8 infections per 100 person-years during mono- or dual-therapy and 10.5 infections per 100 person-years during HAART. The most common OIs both before and after antiretroviral therapy initiation were recurrent upper respiratory tract infections, persistent oral candidiasis and pulmonary tuberculosis. The incidence rates of World Health Organization clinical stage 3 or 4 OIs after HAART were highest among children <18 months of age and those with low weight-for-age z scores, CD4 cell % <15%, and World Health Organization stage 3 at HAART initiation.

CONCLUSIONS

Despite dramatic declines in their incidence, OIs remained important causes of morbidity after HAART initiation in this regional cohort of HIV-infected children in Asia.

Incidence and mortality of tuberculosis disease in Spain between 1997 and 2010: impact of human immunodeficiency virus (HIV) status

OBJECTIVE

To estimate incidence and mortality of TB disease in Spain, as well as TB recurrence and its mortality, and to analyse its trend from 1997 to 2010 in human immunodeficiency virus (HIV)-infected patients (HIV(+) group), compared to HIV-uninfected subjects (HIV(-) group).

METHODS

We performed a retrospective study using data from Minimum Basic Data Set. The outcome variables were new TB diagnosis, TB recurrences, and mortality; which were analysed through three calendar periods related to widespread use of combination antiretroviral therapy (cART): a) From 1997 to 1999 for early-period cART; b) from 2000 to 2003 for mid-period cART; and c) from 2004 to 2008 for late-period cART.

RESULTS

We studied 86,093 HIV-uninfected patients and 17,031 HIV infected patients. TB diagnosis in HIV(-) group (events per 100,000 patients-yr) decreased from 20.16 (1997-1999) to 16.31 (2000-2003; p < 0.001), and later to 13.48 (2004-2010; p < 0.001); and among HIV(+) group (events per 1000 patients-yr) it decreased from 19.23 (1997-1999) to 10.93 (2000-2003; p < 0.001), and later to 6.35 (2004-2010; p < 0.001). For the mortality, HIV(-) group (events per 1,000,000 patients-yr) decreased from 11.5 (1997-1999) to 9.8 (2000-2003; p < 0.001), and later to 7.2 (2004-2010; p < 0.001); and HIV(+) group (events per 10,000 patients-yr) decreased from 20.69 (1997-1999) to 13.20 (2000-2003; p < 0.001), and later to 6.83 (2004-2010; p < 0.001). During the whole period, the diagnostic rate and mortality of TB remained 100-fold higher in HIV(+) group than HIV(-) group (p < 0.001). Moreover, HIV (+) group had higher percentage of patients with TB recurrence than HIV(-) group (p < 0.001).

CONCLUSION

TB diagnosis and mortality decreased in Spain between 1997 and 2010, in both HIV infected patients and people without HIV infection; but these rates remained higher in HIV infected patients.

Tuberculosis incidence in HIV/AIDS patients in Israel, 1983-2010

Objectives

People living with HIV/AIDS (PLWHA) who develop tuberculosis disease are at greater mortality-risk. This study aimed to assess tuberculosis disease incidence among all PLWHA in Israel and identify populations at high-risk for developing tuberculosis.

Design and Methods

Retrospective cohort-study based on the National HIV and Tuberculosis Registries, which were cross-matched and followed for the last 28-years. PLWHA who developed tuberculosis were compared to those who did not by the Cox-proportional analysis to generate hazard-ratios, and survival-analysis was performed by Log-Rank test.

Results

Of all the 6579 PLWHA reported between 1983 and 2010, corresponding to 55737 person-years, 384 (5.8%) developed tuberculosis. Of those, 14 were Israeli-born and 370 were non-Israeli born. The overall tuberculosis incidence-density was 6.9 cases/1000 person-years (95% CI 1.8–12.0). The cumulative tuberculosis-incidence among PLWHA in 2010 was 586 times higher than in HIV-negative individuals (3400 and 5.8 cases per 100000 population, respectively). Higher hazard-ratios to developing tuberculosis were found in migrant citizens PLWHA who were males, non-Israeli born, those who were diagnosed with HIV/AIDS after 1997, those who originated in high-tuberculosis prevalence country and those who acquired HIV by heterosexual or drug-injection transmission. PLWHA who developed tuberculosis had higher odds of dying than other PLWHA (36.5% and 16.6%, respectively, p<0.001, odds ratio = 2.8, 95% confidence-interval 2.3–3.6). In survival-analysis, time to develop tuberculosis was shorter among males than females, in PLWHA who were reported with HIV after 1997, in heterosexual who originated in high-tuberculosis countries, followed by injecting drug-users, heterosexual from low-tuberculosis burden countries and men who have sex with men.

Conclusion

Tuberculosis-incidence is higher among non-Israeli born PLWHA, with decreasing trends from 1991. Despite the moderate TB-rate disease among PLWHA, it remains an important cause for severe morbidity and mortality. Tuberculosis in PLWHA reflects mainly the tuberculosis-burden in the originating country and possibly also the mode of HIV-transmission.

Tuberculosis, injecting drug use and integrated HIV-TB care: a review of the literature

BACKGROUND

People who inject drugs (PWID) are at increased risk of tuberculosis (TB) and reduced retention in treatment. There is a need to document strategies for integrated delivery of HIV, TB and drug dependency care.

METHODS

This article reviews the literature on rates of TB mono- and co-infection, and published and grey literature descriptions of TB and HIV-TB care, among PWID.

RESULTS

Latent TB infection prevalence was high and active disease more common among HIV-positive PWID. Data on multidrug-resistant TB and co-infections among PWID were scarce. Models of TB care fell into six categories: screening and prevention within HIV-risk studies; prevention at TB clinics; screening and prevention within needle-and-syringe-exchange (NSP) and drug treatment programmes; pharmacy-based TB treatment; TB service-led care with harm reduction/drug treatment programmes; and TB treatment within drug treatment programmes. Co-location with NSP and opioid substitution therapy (OST), combined with incentives, consistently improved screening and prevention uptake. Small-scale combined TB treatment and OST achieved good adherence in diverse settings. Successful interventions involved collaboration across services; a client-centred approach; and provision of social care. No peer-reviewed studies described models of integrated HIV-TB care for PWID but grey literature highlighted key components: co-located services, provision of drug treatment, multidisciplinary staff training; and remaining barriers: staffing inefficiencies, inadequate funding, police interference, and limited OST availability.

CONCLUSIONS

Integration with drug treatment improves PWID engagement in TB services but there is a need to document approaches to HIV-TB care, improve surveillance of TB and co-infections among PWID, and advocate for improved OST availability.

Outcomes of antiretroviral therapy in Vietnam: results from a national evaluation

Objectives

Vietnam has significantly scaled up its national antiretroviral therapy (ART) program since 2005. With the aim of improving Vietnam’s national ART program, we conducted an outcome evaluation of the first five years of the program in this concentrated HIV epidemic where the majority of persons enrolled in HIV care and treatment services are people who inject drugs (PWID). The results of this evaluation may have relevance for other national ART programs with significant PWID populations.

Design

Retrospective cohort analysis of patients at 30 clinics randomly selected with probability proportional to size among 120 clinics with at least 50 patients on ART.

Methods

Charts of patients whose ART initiation was at least 6 months prior to the study date were abstracted. Depending on clinic size, either all charts or a random sample of 300 charts were selected. Analyses were limited to treatment-naïve patients. Multiple imputations were used for missing data.

Results

Of 7,587 patient charts sampled, 6,875 were those of treatment-naïve patients (74.4% male, 95% confidence interval [CI]: 72.4–76.5, median age 30, interquartile range [IQR]: 26–34, 62.0% reported a history of intravenous drug use, CI: 58.6–65.3). Median baseline CD4 cell count was 78 cells/mm³ (IQR: 30–162) and 30.4% (CI: 25.8–35.1) of patients were at WHO stage IV. The majority of patients started d4T/3TC/NVP (74.3%) or d4T/3TC/EFV (18.6%). Retention rates after 6, 12, 24, and 36 months were 88.4% (CI: 86.8–89.9), 84.0% (CI: 81.8–86.0), 78.8% (CI: 75.7–81.6), and 74.6% (CI: 69.6–79.0). Median CD4 cell count gains after 6, 12, 24, and 36 months were 94 (IQR: 45–153), 142 (IQR: 78–217), 213 (IQR: 120–329), and 254 (IQR: 135–391) cells/mm³. Patients who were PWID showed significantly poorer retention.

Conclusions

The study showed good retention and immunological response to ART among a predominantly PWID group of patients despite advanced HIV infections at baseline.

Role of raltegravir in HIV-1 management

OBJECTIVE

To review the literature concerning the role of raltegravir in the treatment of HIV-1 in antiretroviral (ARV)-experienced and ARV-naïve patients.

DATA SOURCES

A PubMed search was conducted for published data through March 2012 using the search terms raltegravir, MK-0518, and integrase strand transfer inhibitor. An additional search of International Pharmaceutical Abstracts for unpublished data, including data from the Infectious Diseases Society of America, the Conference on Retroviruses and Opportunistic Infections, the International AIDS Society, and the Interscience Conference on Antimicrobial Agents and Chemotherapy, was conducted using similar search terms.

STUDY SELECTION AND DATA EXTRACTION

In vitro and in vivo Phase 2, Phase 3, and postmarketing studies available in English, evaluating antiretroviral regimens that contain raltegravir for the treatment of HIV-1 infection in both ARV-naïve and ARV-experienced patients, were evaluated. Studies assessing raltegravir pharmacokinetics and pharmacodynamics were included for review.

DATA SYNTHESIS

The nucleoside-based regimen of raltegravir with tenofovir/emtricitabine provides an effective first-line treatment option. However, nucleoside-sparing regimens appear unfavorable in ARV-naïve subjects and should be reserved for patients with limited treatment options. Raltegravir used with optimized background therapy provides an alternative regimen for ARV-experienced patients. This review describes the available in vitro and in vivo data on raltegravir potency, defined as the ability to achieve undetectable viral load, and safety profile, as well as comparison to standard HIV-1 therapies.

CONCLUSIONS

Raltegravir has demonstrated potent antiretroviral activity against HIV-1 in both ARV-naïve and ARV-experienced subjects, with the benefits of a favorable adverse effect profile and minimal drug interactions. Raltegravir must be dosed twice daily, as once daily raltegravir displays decreased virologic efficacy compared to twice daily dosing. However, the ongoing development of new integrase strand transfer inhibitors may provide potent once daily regimens.

Antiretroviral treatment as prevention: impact of the 'test and treat' strategy on the tuberculosis epidemic

Antiretroviral therapy (ART) has been remarkably effective in ameliorating Human Immunodeficiency Virus (HIV)-associated morbidity and mortality. The rapid decline in viral load during ART also presents an opportunity to develop a “treatment as prevention” strategy in order to reduce HIV transmission at a population level. Modelling exercises have demonstrated that for this strategy to be effective, early initiation of ART with high coverage of the HIV-infected population will be required. The HIV epidemic has fueled a resurgence of tuberculosis (TB) particularly in sub-Saharan Africa and widespread early initiation of ART could also impact this epidemic via several mechanisms. The proportion of patients with low CD4 cell counts who are at high risk of TB disease from progression of both latent and new TB infection would be greatly reduced. Entry into a life-long ART program provides an ongoing opportunity for intensified TB case finding among the HIV-infected population. Regular screening for HIV infection also presents an opportunity for intensified TB case finding in the general population. The combined effect of reduced progression of infection to disease and intensified case finding could reduce the overall prevalence of infectious TB, thereby further decreasing TB transmission. In addition, decreasing prevalence of HIV infection would reduce the TB-susceptible pool within the population. The ‘test and treat’ strategy therefore has potential to reduce the TB risk at both an individual and a population level. In this paper we explore the expected “TB dividend” of wider access to ART and also explore the potential of the “test and treat” strategy to impact on TB transmission, particularly in the heavily burdened setting of sub-Saharan Africa.

Reduction in mycobacterial disease among HIV-infected children in the highly active antiretroviral therapy era (1997-2008)

BACKGROUND

HIV-infected children are at increased risk of developing mycobacterial disease. The aim of this study was to estimate the change in mycobacterial disease rate in HIV-infected children and adolescents in the highly active antiretroviral therapy (HAART) era.

METHODS

We carried out a retrospective study. Data were obtained from the records of the minimum basic data set of hospitals in Spain from 1997 to 2008. The epidemiologic trends of mycobacterial diseases were evaluated through the following 3 calendar periods: early-period HAART (1997-1999), midperiod HAART (2000-2002), and late-period HAART (2003-2008).

RESULTS

We analyzed 1307 HIV-infected children and 5228 HIV-uninfected children. HIV-infected children had similar rate of tuberculosis (TB) and nontuberculous mycobacteria (NTM) disease, and they had an overall rate of mycobacterial disease higher than that of HIV-uninfected children (P < 0.001). In HIV-infected children, the highest rates were for pulmonary TB (15/42 [35.7%]) in the TB category and disseminated mycobacterium (9/42 [21.4%]) in the NTM category. The overall rate of mycobacterial disease (events per 1000 HIV-infected children-year) decreased from 1997-1999 to 2003-2008 (5.88-1.63, P = 0.007) and from 2000-2002 to 2003-2008 (4.20-1.63, P = 0.021). Furthermore, the rate of TB decreased from 1997-1999 to 2000-2002 (3.53-0.84, P = 0.016) and from 1997-1999 to 2003-2008 (3.53-1.31, P = 0.030), and the rate of NTM disease decreased from 2000-2002 to 2003-2008 (3.36-0.32, P = 0.002).

CONCLUSIONS

The rate of mycobacterial disease decreased among HIV-infected children in the HAART era, but the incidence of mycobacterial disease still remains higher than in the general population.

Is inadequate human immunodeficiency virus care associated with increased ED and hospital utilization? A prospective study in human immunodeficiency virus-positive ED patients

BACKGROUND

There is a lack of data on the effect(s) of suboptimal human immunodeficiency virus (HIV) care on subsequent health care utilization among emergency department (ED) patients with HIV. Findings on their ED and inpatient care utilization patterns will provide information on service provision for those who have suboptimal access to HIV-related care.

METHODS

A pilot prospective study was conducted on HIV-positive patients in an ED. At enrollment, participants were interviewed regarding health care utilization. Participants were followed up for 1 year, during which time data on ED visits and hospitalizations were obtained from their patient records. Inadequate HIV care (IHC) was defined according to Infectious Diseases Society of America recommendations as less than 3 scheduled clinic visits for HIV care in the year before enrollment. Cox regression models were used to evaluate whether IHC was associated with increased hazard of health care utilization.

RESULTS

Of 107 subjects, 36% were found to have IHC. Inadequate HIV care did not predict more frequent ED visits but was significantly associated with fewer hospitalizations (adjusted incidence rate ratio, 0.61 [95% CI: 0.43-0.86]). Inadequate HIV care did not significantly increase the hazard for earlier ED visit or hospitalization. However, further stratification analysis found that IHC increased the hazard of hospitalization for subjects without comorbid diseases (adjusted hazard ratio, 2.50 [95% CI: 1.10-5.68]).

CONCLUSIONS

In our setting, IHC does not appear to be associated with earlier or more frequent ED visits but may lead to earlier hospitalization, particularly among those without other chronic diseases.

Latent tuberculosis infections in hard-to-reach drug using population-detection, prevention and control

Interferon-gamma release assays (IGRAs) need be evaluated for effectiveness as screening tests for tuberculosis (TB) infection in drug users. These tests have demonstrated improved sensitivity and specificity, but have not been studied in drug users. These one step blood tests are intended to replace the tuberculin skin test (TST), which is difficult to use and requires 48 hour follow-up, so they are expected to be particularly suitable for risk groups, like drug users, in whom follow-up is problematic. Drug users have traditionally been identified as being at increased risk for acquiring TB disease. The results of our pilot study using the TST and simpler and more sensitive interferon-gamma release assays showed that about 45% of current drug users in Houston tested have at least one test positive for latent tuberculosis infection (LTBI). These preliminary data suggest that there is an important reservoir of LTBI in drug using populations, and the risk of progression to active TB disease with other infections is great. However, LTBI in drug using populations has not been studied in depth and deserves further investigation. We need to evaluate the validity of IGRAs for detection of latent TB infection, the factors associated with LTBI, the incidence and risk for developing active TB disease in drug users and the effectiveness of early treatment of LTBI. We believe that using better tuberculosis screening tools will allow us to more accurately measure the prevalence of latent TB infection and incidence of active TB disease in drug using populations and develop more effective TB prevention and treatment interventions in the community.

CD4 cell eligibility thresholds: an analysis of the time to antiretroviral treatment in HIV-1 seroconverters

BACKGROUND

WHO recommends initiating combination antiretroviral treatment at the minimal CD4 cell threshold of 350 cells/μl. In sub-Saharan Africa, the time for a recently infected patient to reach this threshold is unclear.

METHOD

We estimated the probability of reaching different CD4 cell thresholds over time in the ANRS 1220 cohort of HIV-1 seroconverters in Côte d'Ivoire. CD4 cell slopes were estimated using a mixed linear model. Probabilities of crossing the 350 and 500 cells/μl CD4 cell thresholds were estimated by the Kaplan-Meier method.

RESULTS

Between 1997 and 2009, 304 recent seroconverters have been enrolled in the Primo-CI cohort (62% men, median baseline age 29 years and median time since the estimated date of seroconversion 9 months). The probability of having a first CD4 cell count below 500 cells/μl was 0.57, 0.72, 0.79 and 0.84 at study entry, 2, 4 and 6 years, respectively. For a first CD4 cell count below 350 cells/μl, these figures were 0.29, 0.40, 0.55 and 0.67. The time for 75% of patients to reach the threshold was 3.0 years for 500 cells/μl and 7.0 years for 350 cells/μl.

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 and immigration in a high-income country: incidence trends and risk factors in recent years

OBJECTIVE

To examine trends in tuberculosis incidence rates in France during the combination antiretroviral therapy (cART) period.

METHODS

From the French Hospital Database on HIV, we selected 72 580 patients (including 14 491 migrants) with no history of tuberculosis, followed between 1 January 1997 and 31 December 2008. We then examined incidence rates of tuberculosis and its risk factors.

RESULTS

A total of 2625 patients were diagnosed with tuberculosis either at enrollment (N = 932) or during follow-up (N = 1693). During follow-up, the incidence rate of tuberculosis was 0.40/100 patient-years overall, 0.20 among non-migrants and 1.03 among migrants. Adjusted risk of tuberculosis was 2.01 [95% confidence interval (CI) 1.79-2.26] times higher in migrants than in non-migrants. The adjusted incidence rate of tuberculosis significantly increased in both migrants and non-migrants after 2000-2001, with adjusted risks of 2.50 (95% CI 1.54-4.06) and 1.85 (95% CI 1.27-2.69) in 2008 compared with that in 1997, respectively. Other factors independently associated with a higher incidence of tuberculosis were medical follow-up less than or equal to 6 months, no previous antiretroviral therapy, lower CD4 cell count and higher viral load. Non-migrant patients belonging to HIV-transmission groups other than homosexual men, residing in the Paris area or in French West Indies or with AIDS status were at a supplementary risk.

CONCLUSION

The incidence of tuberculosis is increasing among both migrant and non-migrant HIV-infected patients in France. This is partly because sub-Saharan African migrants represent an increasing fraction of the HIV-infected population in France and also because of late access to care. Co-prescribing tuberculosis preventive therapy with cART might benefit selected patients, such as migrants and patients with late access to care.

Influence of HIV infection on mortality in a cohort of patients treated for tuberculosis in the context of wide access to HAART, in Rio de Janeiro, Brazil

OBJECTIVE

To analyze the influence of HIV serostatus on mortality related to tuberculosis (TB) in the context of wide access to highly active antiretroviral therapy (HAART) in a middle-income country.

METHODS

Prospective cohort study including patients who started antituberculous therapy between April 2000 and July 2005 at a referral center in Rio de Janeiro, Brazil.

RESULTS

Two hundred seven patients were enrolled, 106 were seropositive for HIV. There were 21 TB-related deaths in HIV-positive subjects (24.7 deaths per 100 patient-years) and 2 (2.5 deaths per 100 patient-years) among HIV-negative patients (rate ratio = 9.76, P < 0.001). Among HIV-infected subjects, TB-related mortality tended to be lower in patients treated with HAART [hazard ratio (HR) = 0.58, P = 0.06]. However, mortality among patients treated with HAART was still significantly increased as compared with HIV-negative patients (HR = 6.6, P = 0.014). In a Cox regression model adjusted for disseminated TB (P = 0.04), and treatment with antituberculous regimens not containing rifampicin (P = 0.11), mortality was significantly higher among seropositive patients not on HAART compared with HIV-negative subjects (HR = 6.30, P = 0.024). Among subjects treated with HAART, there was a nonsignificant increase in mortality (rate ratio = 3.48, P = 0.14).

CONCLUSIONS

HIV infection still has a substantial impact on TB-related mortality in the context of wide access to HAART in a middle-income country.

Antiretroviral therapy for control of the HIV-associated tuberculosis epidemic in resource-limited settings

Great progress has been made over the past few years in HIV testing in patients who have tuberculosis (TB) and in the scale-up of antiretroviral therapy. More than 3 million people in resource-limited settings were estimated to have started antiretroviral therapy by the end of 2007 and 2 million of these were in sub-Saharan Africa. However, little is known about what impact this massive public health intervention will have on the HIV-associated TB epidemic or how antiretroviral therapy might be used to best effect TB control. This article provides an in-depth review of these issues.

Epidemiology of HIV-associated tuberculosis

PURPOSE OF REVIEW

We review literature concerning the epidemiology of HIV-associated tuberculosis (HIV-TB), focusing on articles published between 2007 and 2008.

RECENT FINDINGS

An estimated 1.37 million new cases of HIV-TB occurred in 2007, representing 15% of the total global burden of TB. In addition, an estimated 456 000 HIV-TB deaths accounted for 23% of global HIV/AIDS mortality. Sub-Saharan Africa is the worst affected region with 79% of the disease burden. The epicentre of the coepidemic lies in the south of the continent, with South Africa alone accounting for over one quarter of all cases. A critical overlap between HIV and the global multidrug-resistant TB epidemics is emerging. Although it is as yet unclear whether HIV is driving a disproportionate increase in multidrug-resistant TB cases at a population level, HIV has nevertheless been a potent risk factor for institutional outbreaks, especially in South Africa and eastern Europe. Increasing data have highlighted the risk of TB among HIV-infected healthcare workers in resource-limited settings. However, many studies also show the major benefits to be derived from antiretroviral therapy in high-income and low-income countries.

SUMMARY

HIV-TB remains a major challenge to global health that requires substantial increases in resource allocation and concerted international action.

Effect of free treatment and surveillance on HIV-infected persons who have tuberculosis, Taiwan, 1993-2006

In 1997, Taiwan made highly active antiretroviral therapy (HAART) available without cost to HIV-infected persons; in 2001, a national web-based surveillance system was implemented. Healthcare workers use the system to monitor patients' conditions and can intervene when necessary. Free HAART, coupled with the surveillance system, appears to have increased survival rates of HIV-infected persons with tuberculosis in Taiwan.

Prospective evaluation of latent tuberculosis with interferon-γ release assays in drug and alcohol abusers

In vitro tests have been developed for the diagnosis of tuberculosis (TB) infection. The objective was to analyse latent TB infection in drug and alcohol abusers through two interferon-γ techniques. One hundred and thirty-nine patients were admitted between February 2006 and May 2007. Mean age was 39·8 years [31% HIV positive]. The enzyme immunoassay (EIA) and enzyme-linked immunospot (ELISPOT) interferon-γ assays were positive in 34% of patients with an agreement of 83% (κ=0·63). Tuberculin skin test (TST) was positive in 29% of patients and the agreement of TST with EIA and ELISPOT interferon-γ assays was 85% (κ=0·62) and 83% (κ=0·57), respectively. Almost 50% of patients with history of TB had a positive in vitro test. In conclusion, we observed a high prevalence of latent TB and good agreement between the new in vitro tests that otherwise may continue to be positive long after developing TB disease.

Changing global epidemiology of pulmonary manifestations of HIV/AIDS

Tremendous advances have occurred in the care of patients with HIV/AIDS resulting from the advent of highly active antiretroviral therapy (HAART). This has led to differences in the presentations of HIV-related pulmonary disease. Infections such as bacterial pneumonias, particularly Streptococcus pneumoniae, remain commonplace, while opportunistic agents such as Pneumocystis jirovecii remain a concern in patients without adequate access to optimal medical care. The tuberculosis epidemic, once thought to be slowing, has been re-energized by the spread of HIV, particularly in sub-Saharan Africa. Unusual inflammatory responses due to a phenomenon of immune reconstitution, are now recognized as a consequence of HAART, with a reported incidence of IRIS in this setting ranges from 7 to 45% in retrospective reviews. Noninfectious pulmonary conditions such as chronic obstructive lung disease and pulmonary malignancies are gaining prominence as patients are accessing antiretroviral care and enjoying significantly extended survival.

Tuberculosis and illicit drug use: review and update

Illicit drug users continue to be a group at high risk for tuberculosis (TB). Here, we present an updated review of the relationship between TB and illicit drug use, and we summarize more than a decade of new research. Drug users, and injection drug users in particular, have driven TB epidemics in a number of countries. The successful identification and treatment of TB among illicit drug users remain important components of a comprehensive TB strategy, but illicit drug users present a unique set of challenges for TB diagnosis and control. New diagnostic modalities, including interferon-gamma-release assays, offer potential for improved diagnosis and surveillance among this group, along with proven treatment strategies that incorporate the use of directly observed therapy with treatment for drug abuse. Special considerations, including coinfection with viral hepatitis and the rifampin-methadone drug interaction, warrant clinical attention and are also updated here.

The spectrum of abdominal tuberculosis in a developed country: a single institution's experience over 7 years

BACKGROUND

The incidence of human immunodeficiency virus (HIV) infection is rising, and as a result, tuberculosis (TB) has become a resurgent problem in many developed countries.

OBJECTIVES

The aim of this study was to review the spectrum of abdominal TB and its surgical management in our institution.

METHODS

A retrospective review of all abdominal TB cases notified to the health authorities by our institution from Jan 01 to Oct 07 was performed.

RESULTS

There were 57 patients (37 men) with abdominal TB, with a median age of 47 (range 14-74) years. Active pulmonary TB was present in 27 patients (47%). Positive HIV status was present in 30% and untested in 58%. The majority of patients underwent computed tomography scans (n = 50, 88%). The main radiological findings included bowel thickening, lymphadenopathy, ascites, free gas suggestive of perforation, and abscesses. The diagnosis of TB was confirmed on microbiological and/or histological examination in 72%, while the remaining 28% were diagnosed based on the clinical presentation and radiological imaging. All patients were commenced on anti-tuberculous therapy. TB involved the small or large bowel in 33 patients, mesenteric lymphadenopathy in 24, peritoneum in 13, spleen in seven, pancreas in two, anus in two, and the liver in two. Disseminated (including pulmonary) TB occurred in 27 patients (47%), while isolated intra-abdominal TB occurred in the remaining 30 patients (53%). Twenty-five patients (44%) underwent surgery--16 laparotomies (six perforated viscus, five intestinal obstruction, three suspected malignancies, and two for suspected acute abdomen), five laparoscopic procedures (four diagnostic, one gastrojejunostomy bypass for gastric outlet obstruction), two appendectomies, one drainage of abscess, and one anal fistulotomy.

CONCLUSIONS

Although TB is eminently treatable medically, surgery is still often required for suspected or confirmed abdominal TB presenting with acute complications or as atypical diagnostic problems. The role of laparoscopy is likely to be more significant in future in the management of abdominal TB.