Effect of simultaneous use of highly active antiretroviral therapy on survival of HIV patients with tuberculosis

Immune Responses in Lung Granulomas during Mtb/HIV Co-Infection: Implications for Pathogenesis and Therapy

HIV and TB are the cause of significant worldwide mortality and pose a grave danger to the global public health. TB is the leading cause of death in HIV-infected persons, with one in four deaths attributable to TB. While the majority of healthy individuals infected with M. tuberculosis (Mtb) are able to control the infection, co-infection with HIV increases the risk of TB infection progressing to TB disease by over 20-fold. While antiretroviral therapy (ART), the cornerstone of HIV care, decreases the incidence of TB in HIV-uninfected people, this remains 4- to 7-fold higher after ART in HIV-co-infected individuals in TB-endemic settings, regardless of the duration of therapy. Thus, the immune control of Mtb infection in Mtb/HIV-co-infected individuals is not fully restored by ART. We do not fully understand the reasons why Mtb/HIV-co-infected individuals maintain a high susceptibility to the reactivation of LTBI, despite an effective viral control by ART. A deep understanding of the molecular mechanisms that govern HIV-induced reactivation of TB is essential to develop improved treatments and vaccines for the Mtb/HIV-co-infected population. We discuss potential strategies for the mitigation of the observed chronic immune activation in combination with both anti-TB and anti-retroviral approaches.

System-wide identification of myeloid markers of TB disease and HIV-induced reactivation in the macaque model of Mtb infection and Mtb/SIV co-infection

Mycobacterium tuberculosis (Mtb) has developed specialized mechanisms to parasitize its host cell, the macrophage. These mechanisms allow it to overcome killing by oxidative burst and persist in the wake of an inflammatory response. Mtb infection in the majority of those exposed is controlled in an asymptomatic form referred to as latent tuberculosis infection (LTBI). HIV is a well-known catalyst of reactivation of LTBI to active TB infection (ATB). Through the use of nonhuman primates (NHPs) co-infected with Mtb and Simian Immunodeficiency Virus (Mtb/SIV), we are able to simulate human progression of TB/AIDS comorbidity. The advantage of NHP models is that they recapitulate the breadth of human TB outcomes, including immune control of infection, and loss of this control due to SIV co-infection. Identifying correlates of immune control of infection is important for both vaccine and therapeutics development. Using macaques infected with Mtb or Mtb/SIV and with different clinical outcomes we attempted to identify signatures between those that progress to active infection after SIV challenge (reactivators) and those that control the infection (non-reactivators). We particularly focused on pathways relevant to myeloid origin cells such as macrophages, as these innate immunocytes have an important contribution to the initial control or the lack thereof, following Mtb infection. Using bacterial burden, C-reactive protein (CRP), and other clinical indicators of disease severity as a guide, we were able to establish gene signatures of host disease state and progression. In addition to gene signatures, clustering algorithms were used to differentiate between host disease states and identify relationships between genes. This allowed us to identify clusters of genes which exhibited differential expression profiles between the three groups of macaques: ATB, LTBI and Mtb/SIV. The gene signatures were associated with pathways relevant to apoptosis, ATP production, phagocytosis, cell migration, and Type I interferon (IFN), which are related to macrophage function. Our results suggest novel macrophage functions that may play roles in the control of Mtb infection with and without co-infection with SIV. These results particularly point towards an interplay between Type I IFN signaling and IFN-γ signaling, and the resulting impact on lung macrophages as an important determinant of progression to TB.

Adherence measured using electronic dose monitoring is associated with emergent antiretroviral resistance and poor outcomes in patients co-infected with HIV/AIDS and multidrug-resistant tuberculosis

BACKGROUND

Medication adherence is known to challenge treatment of HIV/AIDS and multidrug-resistant tuberculosis (MDR-TB). We hypothesized that electronic dose adherence monitoring (EDM) would identify an ART adherence threshold for emergent ART resistance and predict treatment outcomes in patients with MDR-TB and HIV on ART and bedaquiline-containing TB regimens.

METHODS

A prospective cohort of adults with MDR-TB and HIV, on ART and initiating MDR-TB treatment with bedaquiline, were enrolled at a public TB referral hospital in KwaZulu-Natal, South Africa (PRAXIS Study, Clinicaltrials.gov NCT03162107). Participants received separate EDM devices measuring adherence to bedaquiline and ART (nevirapine or lopinavir/ritonavir). Adherence was calculated cumulatively over six months. Participants were followed through completion of MDR-TB treatment. HIV genome sequencing was performed at baseline, 2 and 6 months on samples with HIV RNA ≥1000 copies/mL.

FINDINGS

From November 2016 through February 2018, 198 MDR-TB and HIV co-infected participants were enrolled and followed (median 17.2 months, IQR 12.2 - 19.6). Eleven percent had baseline ART resistance mutations, and 7.5% developed emergent ART resistance at 6 months. ART adherence was independently associated with both emergent ART resistance and mortality. Modeling identified a significant (p<0.001), but linear association between ART adherence and emergent resistance, suggesting a strong association without a specific threshold.

INTERPRETATION

Our findings highlight the need for ART resistance testing, especially in MDR-TB HIV co-infected patients, which is currently not standard of care in resource-limited settings. Despite short follow-up duration, reduced ART adherence was significantly associated with emergent resistance and increased mortality.

HIV TB coinfection - perspectives from India

Introduction: HIV and tuberculosis (TB) are two of the most challenging infections faced by humanity and place immense burden on health care systems worldwide. Both HIV and TB impact one another's progression.Areas covered: HIV is the most important risk factor for progression of latent TB to active disease. TB is the most common cause of death among People Living with HIV (PLHIV). Timely detection of TB among PLHIV and screening for HIV among TB patients, early initiation of ART and ATT among coinfected persons, provision of CPT and TB Preventive therapy along with control of air-borne infection are some of the key activities to reduce morbidity and mortality among coinfected persons. Despite many challenges, the collaboration between two programs has yielded good results and globally more than 7.3 million lives of PLHIV have been saved globally through scale-up of collaborative TB/HIV activities since 2005. The review looked into key features of both programs that are the collaboration strategies and challenges that still need to be addressed.Expert opinion: The overarching principle for effective implementation of collaborative activities is integration of the TB and HIV national programs right from policy making to service delivery and monitoring.

Effects of time of initiation of antiretroviral therapy in the treatment of patients with HIV/TB co-infection: A systemic review and meta-analysis

This systemic review and meta-analysis aimed to investigate the burden of tuberculosis immune reconstitution syndrome (TB-IRIS) and associated mortality to highlight the importance of future direction in preventing and treatment of TB-IRIS. Randomized clinical trials (RCTs) that compared early antiretroviral therapy (ART) versus late ART were included. PubMed, EMBASE, Science Direct and Cochrane Central Register of Controlled Trials electronic databases were searched. This meta-analysis included 8 RCTs with a total of 4, 425 participants. The result of analysis showed that early initiation of ART was associated with increase in TB-IRIS (RR = 1.83; 95% CI: 1.24-2.70, p = 0.002; I2 = 74%, p = 0.0007) and TB-IRIS associated mortality (RR = 6.05; 95% CI: 1.06-34.59, p = 0.04; I2 = 0%, p = 0.78). Early ART was associated with overall mortality compared with late ART initiation. Grade 3 or 4 adverse events, achieving lower viral load and development of new AIDS-defining illness were not associated with the time of ART initiation. Early ART in HIV/TB co-infected patients resulted conclusive evidence of increased TB-IRIS incidence and TB-IRIS associated mortality. Hence, the finding calls for clinical judgment as to the benefits of initiating ART earlier against the risk of TB-IRIS and associated mortality.

Improving survival with tuberculosis & HIV treatment integration: A mini-review

Tuberculosis (TB) is a leading cause of morbidity and mortality among HIV-infected patients while HIV remains a key risk factor for the development of active TB infection. Treatment integration is a key in reducing mortality in patients with HIV-TB co-infection. However, this opportunity to improve outcomes of both infections is often missed or poorly implemented. Challenges in TB-HIV treatment integration range from complexities involving clinical management of co-infected patients to obstacles in health service-organization and prioritization. This is evident in high prevalence settings such as in sub-Saharan Africa where TB-HIV co-infection rates reach up to 80 per cent. This review discusses published literature on clinical trials and cohort studies of strategies for TB-HIV treatment integration aimed at reducing co-infection mortality. Studies published since 2009, when several treatment guidelines recommended treatment integration, were included. A total of 43 articles were identified, of which a total of 23 observational studies and nine clinical trials were informative on TB-HIV treatment integration. The data show that the survival benefit of AIDS therapy in patients infected with TB can be maximized among patients with advanced immunosuppression by starting antiretroviral therapy (ART) soon after TB treatment initiation, i.e. in patients with CD4+ cell counts <50 cells/μl. However, patients with greater CD4+ cell counts should defer initiation of ART to no less than eight weeks after initiation of TB treatment to reduce the occurrence and extent of immune reconstitution disease and subsequent hospitalization. Addressing operational challenges in integrating TB-HIV care can significantly improve patient outcomes, generate substantial public health impact by decreasing morbidity and death in settings with a high burden of HIV and TB.

Determinants of AIDS and non-AIDS related mortality among people living with HIV in Shiraz, southern Iran: a 20-year retrospective follow-up study

Background

Human Immunodeficiency Virus (HIV) infection has become a global concern. Determining the factors leading to death among HIV patients helps controlling Acquired Immune Deficiency Syndrome (AIDS) epidemic. Up to now, little is known about mortality and its determinants among people living with HIV in the Middle East and North Africa (MENA) region, including Iran. The purpose of this study was to assess the risk factors of AIDS-Related Mortality (ARM) and Non-AIDS-Related Mortality (NARM) among people with HIV in Iran.

Methods

This 20-year retrospective study was conducted on 1160 people with HIV whose data were collected from 1997 to 2017. The association of the study outcomes (ARM and NARM) with various study variables, including demographic status at the time of diagnosis and clinical indexes during the follow-up were examined to define the predictors of mortality among the patients. Regarding, Cox proportional hazard and competing risk models were fitted and Adjusted Hazard Ratios (AHR), Sub-distribution Hazard Ratio (SHR) and the 95% Confidence Intervals (CI) were reported.

Results

during the follow-up period, 391 individuals (33.7%) died with 86,375 person-years of follow-up. Of the total deaths, 251 (64.2%) and 140 (35.8%) were ARM and NARM, respectively. Rates of the mortality caused by AIDS and non-AIDS were 3.2 and 4.5 per 1000 person-months, respectively. Responding to combined Antiretroviral Treatment (cART) 6 months after initiation, receiving Pneumocystis Pneumonia (PCP) prophylaxis, and higher CD4 count at diagnosis, reduced the hazard of ARM and NARM. However, older age, late HIV diagnosis, and last HIV clinical stages increased the hazard of AIDS related to mortality. Additionally, male gender, older age, incarceration history, and last HIV clinical stages increased the non-AIDS mortality.

Conclusions

Mortality caused by AIDS and non-AIDS remains high among people with HIV in Iran, particularly among males and those with late diagnosis. It seems that applying effective strategies to identify infected individuals at earlier stage of the infection, and targeting individuals with higher risk of mortality can decrease the mortality rate among HIV infected people.

Effect of First-Line Antituberculosis Therapy on Nevirapine Pharmacokinetics in Children Younger than Three Years Old

Nevirapine-based antiretroviral therapy (ART) is one of the limited options in HIV-infected children younger than 3 years old (young children) with tuberculosis (TB) coinfection. To date, there are insufficient data to recommend nevirapine-based therapy during first-line antituberculosis (anti-TB) therapy in young children. We compared nevirapine pharmacokinetics (PK) in HIV-infected young children with and without TB coinfection. In the coinfected group, nevirapine PK was evaluated while on anti-TB therapy and after completing an anti-TB therapy regimen. Of 53 participants, 23 (43%) had TB-HIV coinfection. While the mean difference in nevirapine PK parameters between the two groups was not significant (P > 0.05), 14/23 (61%) of the children with TB-HIV coinfection and 9/30 (30%) with HIV infection had a nevirapine minimum concentration (Cmin) below the proposed target of 3.0 mg/liter (P = 0.03). In multivariate analysis, anti-TB therapy and the CYP2B6 516G>T genotype were joint predictors of nevirapine PK parameters. Differences in nevirapine PK parameters between the two groups were significant in children with CYP2B6 516GG but not the GT or TT genotype. Among 14 TB-HIV-coinfected participants with paired data, the geometric mean Cmin and area under the drug concentration-time curve from time zero to 12 h (AUC0-12) were about 34% lower when patients were taking anti-TB therapy, while the nevirapine apparent oral clearance (CL/F) was about 45% higher. While the induction effect of anti-TB therapy on nevirapine PK in our study was modest, the CYP2B6 genotype-dependent variability in the TB drug regimen effect would complicate any dose adjustment strategy in young children with TB-HIV coinfection. Alternate ART regimens that are more compatible with TB treatment in this age group are needed. (This study has been registered at ClinicalTrials.gov under identifier NCT01699633.).

HIV and tuberculosis co-infection in East Asia and the Pacific from 1990 to 2017: results from the Global Burden of Disease Study 2017

Background

Periodic surveillance is crucial to provide information for resource allocation to control HIV/AIDS, tuberculosis (TB), and their co-infection, especially in areas with high morbidity and mortality like East Asia and the Pacific. Therefore, we examined the morbidity and mortality of HIV/AIDS and TB co-infection in this region from 1990 to 2017.

Methods

Utilizing the Global Burden of Disease (GBD) Study 2017, we obtained incidence, prevalence, and mortality numbers and rates of HIV/AIDS and TB co-infection, including HIV and drug-susceptible TB (DS-TB), multidrug-resistant TB without extensive drug resistance (MDR-TB without XDR), and extensive drug-resistant TB (XDR-TB). The trends in incidence, prevalence, and mortality from 1990 to 2017 for each co-infection type were analyzed using join-point regression modelling.

Results

In 2017, there were 238,372, 4,294, and 392 new cases of HIV-infected DS-TB, HIV-infected MDR-TB without XDR, and HIV-infected XDR-TB, respectively. The number of prevalent cases and deaths were 383,809 and 12,197 of HIV-infected DS-TB, 7,811 and 1,168 of HIV-infected MDR-TB without XDR, and 713 and 282 of HIV-infected XDR-TB. From 1990 to 2017, the age-standardized incidence rate and prevalence rate of HIV-infected DS-TB, and the prevalence rate of HIV-infected XDR-TB continuously increased; the incidence rate of HIV-infected XDR-TB increased from 1990 to 2005 before stabilizing. However, the incidence and prevalence rates of HIV-infected MDR-TB without XDR-as well as the mortality rates of all co-infection types-have decreased in the last 5 years.

Conclusions

Even though the mortality rates of all HIV and TB co-infection types have decreased recently, the overall trends in both incidence and prevalence rates of HIV-infected DS-TB and XDR-TB have been increasing since 1990. Efforts to control co-infection across drug resistance types should be continued and further strengthened.

Time to death and risk factors among tuberculosis patients in Northern Ethiopia

OBJECTIVE

The main objective of this study was to assess time to death and associated risk factors among tuberculosis (TB) patients.

RESULTS

A total of 769 TB patients were studied and of those, 87 (11.3%) patients died. All of the deaths occurred within 7 months of anti-tuberculosis therapy. Extra-pulmonary TB (AHR = 17.376, 95% CI; 3.88-77.86, p < 0.001) as compared to pulmonary TB and cotrimoxazole prophylaxis therapy (CPT) (AHR = 0.15, 95% CI; 0.03-0.74, p = 0.02) were found to be the predictors of mortality. We noticed higher rates of mortality. Extra-pulmonary TB patients have high risk and TB-HIV co-infected patients who received CPT have low risk of death. Improving early diagnosis of extra-pulmonary TB and early CPT initiation of TB-HIV co-infected patients could minimize patient's mortality.

Biomarkers Associated with Death After Initiating Treatment for Tuberculosis and HIV in Patients with Very Low CD4 Cells

Background

The risk of short-term death for treatment naive patients dually infected with Mycobacterium tuberculosis and HIV may be reduced by early anti-retroviral therapy. Of those dying, mechanisms responsible for fatal outcomes are unclear. We hypothesized that greater malnutrition and/or inflammation when initiating treatment are associated with an increased risk for death.

Methods

We utilized a retrospective case-cohort design among participants of the ACTG A5221 study who had baseline CD4 < 50 cells/mm³. The case-cohort sample consisted of 51 randomly selected participants, whose stored plasma was tested for C-reactive protein, cytokines, chemokines, and nutritional markers. Cox proportional hazards models were used to assess the association of nutritional, inflammatory, and immunomodulatory markers for survival.

Results

The case-cohort sample was similar to the 282 participants within the parent cohort with CD4 <50 cells/mm³. In the case cohort, 7 (14%) had BMI < 16.5 (kg/m²) and 17 (33%) had BMI 16.5-18.5(kg/m²). Risk of death was increased per 1 IQR width higher of log₁₀ transformed level of C-reactive protein (adjusted hazard ratio (aHR) = 3.42 [95% CI = 1.33-8.80], P = 0.011), interferon gamma (aHR = 2.46 [CI = 1.02-5.90], P = 0.044), MCP-3 (3.67 [CI = 1.08-12.42], P = 0.037), and with IL-15 (aHR = 2.75 [CI = 1.08-6.98], P = 0.033) and IL-17 (aHR = 3.99 [CI = -1.06-15.07], P = 0.041). BMI, albumin, hemoglobin, and leptin levels were not associated with risk of death.

Conclusions

Unlike patients only infected with M. tuberculosis for whom malnutrition and low BMI increase the risk of death, this relationship was not evident in our dually infected patients. Risk of death was associated with significant increases in markers of global inflammation along with soluble biomarkers of innate and adaptive immunity.

Predictors of mortality in adults on treatment for human immunodeficiency virus-associated tuberculosis in Botswana: A retrospective cohort study

Mortality in patients with human immunodeficiency virus (HIV)-associated tuberculosis (TB) is high, particularly in sub-Saharan Africa. This study aimed to compare mortality and predictors of mortality in those who were antiretroviral therapy (ART) naïve to those with prior ART exposure.This retrospective cohort study was conducted in Serowe/Palapye District, Botswana, a predominantly urban district with a large burden of HIV-associated TB with a high case fatality. Between January 1, 2013 and December 31, 2013, patients confirmed with HIV-associated TB were enrolled and followed up. Kaplan-Meier and Cox proportional hazard modeling was undertaken to identify predictors of mortality, with ART initiation included as time-updated variable.Among the 300 patients enrolled in the study, 131 had started ART before TB diagnosis (44%). There were 45 deaths. There was no difference in mortality between ART-naïve patients and those with prior ART exposure. In the multivariate analysis, no ART use during TB treatment (hazard ratio [HR] = 5.6, 95% confidence interval [CI] = 2.9-11; P < .001), opportunistic infections other than TB (HR = 8.5, 95% CI = 4-18.4; P = .013), age ≥60 years (HR = 4.8, 95% CI = 1.8-13; P = .002), hemoglobin <10 g/dL (HR = 2.4, 95% CI = 1.3-4.5) and hepatotoxicity (HR = 5, 95% CI = 1.6-17; P = .007) were associated with increased mortality. In the subgroup analysis, among ART-naïve patients, no ART use during TB treatment (HR = 8.1, 95% CI = 3.4-19.4; P < .001), opportunistic infections other than TB (HR = 16, 95% CI = 6.2-42; P < .001), and hepatotoxicity (HR = 8.3, 95% CI = 2.6-27; P < .001) were associated with mortality. Among patients with prior ART exposure, opportunistic infections other than TB (HR = 6, 95% CI = 2.6-27; P < .001) were associated with mortality.Mortality in patients with HIV-associated TB is still high. To reduce mortality, close clinical monitoring of patients together with initiation of ART during TB treatment is indicated.

Treatment Outcomes of Children With HIV Infection and Drug-resistant TB in Three Provinces in South Africa, 2005-2008

OBJECTIVE

To describe outcomes of HIV-infected pediatric patients with drug-resistant tuberculosis (DR TB).

METHODS

Demographic, clinical and laboratory data from charts of pediatric patients treated for DR TB during 2005-2008 were collected retrospectively from 5 multi-DR TB hospitals in South Africa. Data were summarized, and Pearson χ test or Fisher exact test was used to assess differences in variables of interest by HIV status. A time-to-event analysis was conducted using days from start of treatment to death. Variables of interest were first assessed using the Kaplan-Meier method. Cox proportional hazard models were fit to estimate crude and adjusted hazard ratios.

RESULTS

Of 423 eligible participants, 398 (95%) had culture-confirmed DR TB and 238 (56%) were HIV infected. A total of 54% were underweight, 42% were male and median age was 10.7 years (interquartile range: 5.5-15.3). Of the 423 participants, 245 (58%) were successfully treated, 69 (16%) died, treatment failed in 3 (1%), 36 (9%) were lost to follow-up and 70 (17%) were still on treatment, transferred or had unknown outcomes. Time to death differed by HIV status (P = 0.008), sex (P < 0.001), year of tuberculosis diagnosis (P = 0.05) and weight status (P = 0.002). Over the 2-year risk period, the adjusted rate of death was 2-fold higher among participants with HIV compared with HIV-negative participants (adjusted hazard ratio = 2.28; 95% confidence interval: 1.11-4.68).

CONCLUSIONS

Male, underweight and HIV-infected children with DR TB were more likely to experience death when compared with other children with DR TB within this study population.

Modeling the causal effect of treatment initiation time on survival: Application to HIV/TB co-infection

The timing of antiretroviral therapy (ART) initiation for HIV and tuberculosis (TB) co-infected patients needs to be considered carefully. CD4 cell count can be used to guide decision making about when to initiate ART. Evidence from recent randomized trials and observational studies generally supports early initiation but does not provide information about effects of initiation time on a continuous scale. In this article, we develop and apply a highly flexible structural proportional hazards model for characterizing the effect of treatment initiation time on a survival distribution. The model can be fitted using a weighted partial likelihood score function. Construction of both the score function and the weights must accommodate censoring of the treatment initiation time, the outcome, or both. The methods are applied to data on 4903 individuals with HIV/TB co-infection, derived from electronic health records in a large HIV care program in Kenya. We use a model formulation that flexibly captures the joint effects of ART initiation time and ART duration using natural cubic splines. The model is used to generate survival curves corresponding to specific treatment initiation times; and to identify optimal times for ART initiation for subgroups defined by CD4 count at time of TB diagnosis. Our findings potentially provide 'higher resolution' information about the relationship between ART timing and mortality, and about the differential effect of ART timing within CD4 subgroups.

Mortality among tuberculosis patients under DOTS programme: a historical cohort study

Background

In high human immunodeficiency virus (HIV) prevalence population, tuberculosis (TB) is the leading cause of morbidity and mortality. HIV is driving the TB epidemic in many countries, especially those in sub-Saharan Africa. We assessed the survival time and predictors of mortality among tuberculosis patients under directly observed treatment, short course (DOTS) strategy in Dessie Referral Hospital tuberculosis clinic, Northeast Ethiopia.

Method

A historical cohort design was utilized to assess survival time and determinants of mortality. A total of 1260 records of patients who started ant-tuberculosis treatment from January 2006 up to December 2010 were analyzed. Survival curves were estimated using Kaplan–Meier and were compared using the Log-rank test. The Cox proportional hazard model was used to assess the relationship between baseline variables and mortality.

Results

Out of the 1260 registered patients, 117 (9.3 %) died over the entire follow-up period. Among those died, 113 (18 %) were HIV positive and 4 (0.6 %) were HIV negative. The 1260 patients contributed a cumulative total of 634.25 person‑years observation.

Conclusion

The mortality of HIV positive tuberculosis patients was higher than those of HIV negative patients and the use of cotrimoxazole preventive therapy increased the survival time of patients.

The impact of HIV status and antiretroviral treatment on TB treatment outcomes of new tuberculosis patients attending co-located TB and ART services in South Africa: a retrospective cohort study

Background

The implementation of collaborative TB-HIV services is challenging. We, therefore, assessed TB treatment outcomes in relation to HIV infection and antiretroviral therapy (ART) among TB patients attending a primary care service with co-located ART and TB clinics in Cape Town, South Africa.

Methods

In this retrospective cohort study, all new TB patients aged ≥ 15 years who registered and initiated TB treatment between 1 October 2009 and 30 June 2011 were identified from an electronic database. The effects of HIV-infection and ART on TB treatment outcomes were analysed using a multinomial logistic regression model, in which treatment success was the reference outcome.

Results

The 797 new TB patients included in the analysis were categorized as follows: HIV- negative, in 325 patients (40.8 %); HIV-positive on ART, in 339 patients (42.5 %) and HIV-positive not on ART, in 133 patients (16.7 %). Overall, bivariate analyses showed no significant difference in death and default rates between HIV-positive TB patients on ART and HIV-negative patients. Statistically significant higher mortality rates were found among HIV-positive patients not on ART compared to HIV-negative patients (unadjusted odds ratio (OR) 3.25; 95 % confidence interval (CI) 1.53–6.91). When multivariate analyses were conducted, the only significant difference between the patient categories on TB treatment outcomes was that HIV-positive TB patients not on ART had significantly higher mortality rates than HIV-negative patients (adjusted OR 4.12; 95 % CI 1.76–9.66). Among HIV-positive TB patients (n = 472), 28.2 % deemed eligible did not initiate ART in spite of the co-location of TB and ART services. When multivariate analyses were restricted to HIV-positive patients in the cohort, we found that being HIV-positive not on ART was associated with higher mortality (adjusted OR 7.12; 95 % CI 2.95–18.47) and higher default rates (adjusted OR 2.27; 95 % CI 1.15–4.47).

Conclusions

There was no significant difference in death and default rates between HIV-positive TB patients on ART and HIV negative TB patients. Despite the co-location of services 28.2 % of 472 HIV-positive TB patients deemed eligible did not initiate ART. These patients had a significantly higher death and default rates.

[Therapeutic outcomes of anti-tuberculosis treatment in the context of HIV-tuberculosis co-infection: Cohort of Kabinda Center in Kinshasa, Democratic Republic of Congo]

BACKGROUND

The study aimed to determine the clinical forms of tuberculosis and therapeutic outcome of anti-tuberculosis treatment in the context of HIV-tuberculosis co-infection.

METHODS

A retrospective cohort of 120 HIV-positive patients with tuberculosis and 297 HIV-negative patients with tuberculosis attending the Kabinda Center was followed from 2010 to June, 30th 2013. The logistic regression model identified the determinants of a defavorable outcome after initiation of tuberculostatics.

RESULTS

The proportion of female patients was higher in the co-infected group compared with the non-co-infected group (60.8% versus 42.7%, P<0.001). HIV-seropositive patients had more forms of pulmonary smear-negative (39.2% versus 25.3%, P<0.002) and extra-pulmonary (38% versus 35%, P<0.002) tuberculosis than HIV-negative patients. HIV-positive serology (OR: 3.13, 95%CI: 1.72-5.69) and age of patients more than 41 years (OR: 3.15, 95%CI: 1.36-7.29) were associated with an unfavorable outcome.

CONCLUSION

This study highlights the usefulness of a systematically determining immunological status in co-infected patients and a timely and systematic ARV treatment, together with early diagnosis of tuberculosis. It also emphasizes the importance of adherence to support measures in order to improve tuberculosis treatment outcomes in co-infected patients.

Timing and uptake of ART during treatment for active tuberculosis in HIV co-infected adults in Malawi

SETTING

Uptake of antiretroviral therapy (ART) in patients co-infected with tuberculosis (TB) and the human immunodeficiency virus (HIV) has historically been low in Malawi. In response, the National TB Programme piloted the initiation of ART 2 weeks after initiation of TB treatment in 2008-2009, a change from the prior policy of 2 months.

OBJECTIVE

To determine at programme level if earlier initiation of ART in co-infected patients receiving TB treatment will increase the uptake and continuation of ART.

DESIGN

A prospective observational pilot programme evaluation using routinely collected monitoring data from the first two sites with integrated TB-HIV services in Malawi.

RESULTS

There was wide variability in the ART start time before and after the policy change. Before the policy change, 16% of patients initiated ART by 3 months compared to 24% after the policy change (P < 0.001). The proportion of all co-infected patients on ART increased from 32% before the policy change to 39% after (P < 0.001). Earlier initiation of ART did not increase the occurrence of side effects and did not reduce adherence to TB treatment.

CONCLUSION

Earlier initiation of ART in co-infected patients receiving TB treatment improved the uptake and continuation of ART. Malawi ART guidelines in 2011 were changed from initiating ART after 2 months to as soon as possible after starting anti-tuberculosis treatment.

Early versus Delayed Antiretroviral Therapy for HIV and Tuberculosis Co-Infected Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

To compare important clinical outcomes between early and delayed initiation of antiretroviral therapy (ART) in adults who had a co-infection of human immunodeficiency virus (HIV) and tuberculosis (TB).

Methods

We performed a systematic search for relevant publications on PubMed, EMBASE, and the International Clinical Trials Registry Platform. We included randomized controlled trials (RCTs) that compared early ART initiation (within four weeks after anti-TB treatment starting) and delayed ART initiation (after eight weeks but less than twelve weeks of anti-TB treatment starting) in the course of TB treatment. Pooled estimates with corresponding 95% confidence interval (95%CI) were calculated with random-effects model. Sensitivity analysis was performed to investigate the stability of pooled estimates.

Results

A meta-analysis was evaluated from six RCTs with 2272 participants. Compared to delayed ART initiation, early ART initiation significantly reduces all-cause mortality in HIV-positive patients with TB [incidence rate ratio (IRR) 0.75, 95%CI 0.59 to 0.95; I² = 0.00%; p = 0.67], even though there is an increased risk for IRD [IRR 2.29, 95%CI 1.81 to 2.91; I²2 = 0.00%; p = 0.56]. Additionally, early ART initiation was not associated with an increased risk for grade 3-4 drug-related adverse events [IRR 0.99, 95%CI 0.83 to 1.18; I² = 0.00%; p = 0.56].

Conclusions

Although limited evidence, our results provide support for early ART initiation in the course of anti-TB treatment. However, more well-designed cohort or intervention studies are required to further confirm our findings.

Opportunistic infections and immune reconstitution inflammatory syndrome in HIV-1-infected adults in the combined antiretroviral therapy era: a comprehensive review

Despite the availability of effective combined antiretroviral treatment, many patients still present with advanced HIV infection, often accompanied by an AIDS-defining disease. A subgroup of patients starting antiretroviral treatment under these clinical conditions may experience paradoxical worsening of their disease as a result of an exaggerated immune response towards an active (but also subclinical) infectious agent, despite an appropriate virological and immunological response to the treatment. This clinical condition, known as immune reconstitution inflammatory syndrome, may cause significant morbidity and even mortality if it is not promptly recognized and treated. This review updates current knowledge about the incidence, diagnostic criteria, risk factors, clinical manifestations, and management of opportunistic infections and immune reconstitution inflammatory syndrome in the combined antiretroviral treatment era.

Survival of HIV patients with tuberculosis started on simultaneous or deferred HAART in the THRio cohort, Rio de Janeiro, Brazil

Background

The timing of highly active antiretroviral therapy (HAART) after a tuberculosis diagnosis in HIV-infected patients can affect clinical outcomes and survival. We compared survival after tuberculosis diagnosis in HIV-infected adults who initiated HAART and tuberculosis therapy simultaneously to those who delayed the start of HAART for at least two months.

Methods

The THRio cohort includes 17,983 patients receiving HIV care in 29 public clinics in Rio de Janeiro, Brazil. HAART-naïve patients at the time of a new TB diagnosis between September 2003 and June 2008 were included. Survival was measured in days from diagnosis of TB. We compared survival among patients who initiated HAART within 60 days of TB treatment (simultaneous – ST) to those who started HAART >60 days of TB treatment or never started (deferred – DT). Kaplan–Meier plots and Cox proportional hazards regression analyses were conducted.

Results

Of 947 patients diagnosed with TB, 572 (60%) were HAART naïve at the time of TB diagnosis; 135 were excluded because of missing CD4 count results. Among the remaining 437 TB patients, 56 (13%) died during follow-up: 25 (10%) among ST patients and 31 (16%) in DT group (p = 0.08). ST patients had lower median CD4 counts at TB diagnosis than DT patients (106 vs. 278, p < 0.001). Cox proportional hazards utilizing propensity score analysis showed that DT patients were more likely to die (adjusted HR = 1.89; 95% CI: 1.05–3.40; p = 0.03).

Conclusion

HAART administered simultaneously with TB therapy was associated with improved survival after TB diagnosis. HAART should be given to patients with HIV-related TB as soon as clinically feasible.

The impact of HAART initiation timing on HIV-TB co-infected patients, a retrospective cohort study

BACKGROUND

Optimal timing for initiating highly active antiretroviral therapy (HAART) in HIV-TB coinfected patients is challenging for clinicians. We aim to evaluate the impact of different timing of HAART initiation on TB outcome of HIV-infected adults in Taiwan.

METHODS

A population-based retrospective cohort study was conducted through linking the HIV and TB registries of Taiwan Centers for Disease Control (CDC) during 1997 to 2006. Clinical data of HIV-TB co-infected patients, including the presence of immune reconstitution inflammatory syndrome (IRIS), was collected through medical records review. The outcome of interest was all-cause mortality within 1 year following TB diagnosis. The Cox proportional hazard model was used to explore the probability of death and IRIS after TB diagnosis by adjusting for confounding factors and factors of interest. The probability of survival and TB IRIS were calculated by the Kaplan-Meier method and compared between different HAART initiation timing groups by the log-rank test.

RESULTS

There were 229 HIV-TB co-infected patients included for analysis and 60 cases (26.2%) died within one year. Besides decreasing age and increasing CD4 lymphocyte count, having started HAART during TB treatment was significantly associated with better survival (adjusted Hazard Ratio was 0.11, 95% CI 0.06-0.21). As to the timing of HAART initiation, there was only non-significant benefit on survival among cases initiating HAART within 15 days, at 16-30 days and at 31-60 days of TB treatment than initiating after 60 days. Cases with HAART initiated after 30 days had lower risk in developing IRIS than cases with HAART initiated earlier. Cases with IRIS had significantly higher rate of re-hospitalization (49% vs. 4%, p < 0.001) and prolonged hospitalization (28 days vs. 18.5 days, p < 0.01).

CONCLUSION

The present study found that starting HAART during TB treatment is associated with better one-year survival, although earlier initiation within 60 days of TB treatment did not show statistical differences in survival than later initiation. Initiation of HAART within 30 days appeared to increase the risk of IRIS. Deferring HAART to 31-60 days of TB treatment might be optimal after considering the risks and benefits.

Plasma LL-37 correlates with vitamin D and is reduced in human immunodeficiency virus-1 infected individuals not receiving antiretroviral therapy

Low levels of the vitamin D-regulated antimicrobial peptide cathelicidin (LL-37) may negatively impact the immune status of human immunodeficiency virus-1 (HIV-1) infected individuals (HIV+). We compared plasma LL-37 levels in healthy controls (HIV-) and HIV+ individuals on or off antiretroviral therapies (ARTs) (ART+ and ART-, respectively), and evaluated the relationship between vitamin D and LL-37 levels. In this cross-sectional study, levels of LL-37, 25-hydroxycholecalciferol [25(OH)D3] and 1,25-dihydroxycholecalciferol [1,25(OH)2D3] were measured from an initial cohort of 18 healthy controls and 10 HIV+/ART- individuals. Because this cohort lacked HIV+/ART+ subjects, LL-37 was also quantified from a second cohort of 10 HIV+/ART- and 13 HIV+/ART+ individuals. LL-37 levels were significantly lower in the HIV+/ART- group compared to the healthy controls (P = 0.01). A direct relationship was observed between LL-37 and both 25(OH)D3 and 1,25(OH)2D3. The level of 25(OH)D3 was predictive of higher LL-37 (P = 0.04) and for any given level of 25(OH)D3, HIV+/ART- subjects averaged 20 % lower LL-37 compared to the healthy controls (P = 0.045). For any given level of 1,25(OH)2D3, HIV+/ART- subjects averaged 25% lower LL-37 compared to the healthy controls (P = 0.018), although 1,25(OH)2D3 was not predictive of higher LL-37 (P = 0.28). Finally, LL-37 levels were significantly lower in the HIV+/ART- group compared to the HIV+/ART+ group from the second cohort (P = 0.045). Untreated HIV infection may contribute to lower LL-37 levels, independent of vitamin D levels. ART treatment may potentially mitigate this decrease in LL-37 levels.

Empirical treatment for TB in HIV: lessons from a cohort study of people living with HIV treated in Recife, Brazil

Background

Tuberculosis (TB) is the leading cause of death related to HIV worldwide. This study analyzes the survival of People Living with HIV (PLHIV) reporting cough without bacteriological confirmation of TB and identify factors associated with death.

Methods

Prospective cohort with a consecutive sample of PLHIV, aged ≥ 18 years. Patient inclusion criteria were complaint of current cough of any duration at the time of the first study interview or during their subsequent routine visits to health services and for whom AFB sputum smear was either negative or not performed during the whole follow-up period. Kaplan-Meier method was used to calculate the probability of survival. We estimated the Hazard Ratio (HR) in bivariate and multivariate Cox regression analyses.

Results

Mortality was 4.6 per 100 py; 73% were receiving HAART at recruitment. Average time from the first recorded date of cough until empirical treatment for tuberculosis was six months. Mortality was higher when the CD4 count was low (HR = 5.3; CI 95%: 3.2-9.0; p = 0.000), in those with anemia (HR = 3.0; CI 95%: 1.6-5.6; p = 0.001) and with abnormal chest X-rays (HR = 2.4; CI 95%: 1.4-4.0; p = 0.001). Mortality was higher in those receiving empirical TB treatment (HR = 2.4; CI 95%: 1.4-4.0; p = 0.002), but only in those with normal X-rays, no history of tuberculosis and no bacteriology requests. Empirical treatment for TB was more frequent in PLHIV with low CD4 counts, anemia, history of opportunistic infections, weight loss, previous tuberculosis, negative bacteriology test (as opposed to not having a test) and abnormal chest X-ray.

Conclusions

Higher mortality in PLHIV reporting a current cough without bacteriological confirmation of tuberculosis was identified for those with a CD4 cell count <200, abnormal chest X-ray, anemia and empirical treatment for tuberculosis. Mortality was not significantly higher in those empirically treated for TB, who had three characteristics suggestive of the disease (abnormal chest X-ray, history of TB treatment, AFB sputum smear or M.tb culture testing). Routine cohorts are not an adequate setting to evaluate the impact of empirical treatment for TB on the mortality of PLHIV.

Global control of tuberculosis: from extensively drug-resistant to untreatable tuberculosis

Extensively drug-resistant tuberculosis is a burgeoning global health crisis mainly affecting economically active young adults, and has high mortality irrespective of HIV status. In some countries such as South Africa, drug-resistant tuberculosis represents less than 3% of all cases but consumes more than a third of the total national budget for tuberculosis, which is unsustainable and threatens to destabilise national tuberculosis programmes. However, concern about drug-resistant tuberculosis has been eclipsed by that of totally and extremely drug-resistant tuberculosis--ie, resistance to all or nearly all conventional first-line and second-line antituberculosis drugs. In this Review, we discuss the epidemiology, pathogenesis, diagnosis, management, implications for health-care workers, and ethical and medicolegal aspects of extensively drug-resistant tuberculosis and other resistant strains. Finally, we discuss the emerging problem of functionally untreatable tuberculosis, and the issues and challenges that it poses to public health and clinical practice. The emergence and growth of highly resistant strains of tuberculosis make the development of new drugs and rapid diagnostics for tuberculosis--and increased funding to strengthen global control efforts, research, and advocacy--even more pressing.

Tuberculosis-immune reconstitution inflammatory syndrome in HIV: from pathogenesis to prediction

Tuberculosis-immune reconstitution inflammatory syndrome (TB-IRIS) is an exaggerated, dysregulated immune response against dead or viable antigens of Mycobacterium tuberculosis that frequently occurs after initiation of antiretroviral therapy despite an effective suppression of HIV viremia. Scientific advances in IRIS pathogenesis have led researchers and clinicians to postulate risk factors that could possibly predict this syndrome, in an attempt to reduce the incidence and the severity of IRIS, with appropriate anti-inflammatory therapy. This review is a summary of the available literature on pathogenic mechanisms involved from the macro to the micro level, the clinical spectrum, available predictors and the scope of these biomarkers to function as specific therapeutic targets, that could effectively modulate or ameliorate this syndrome in future.

Initiation of antiretroviral therapy

With the widespread availability of antiretroviral therapy, there is a dramatic decline in HIV related morbidity and mortality in both developed and developing countries. Further, the current antiretroviral drug combinations are safer and the availability of newer monitoring assays and guidelines has vastly improved the patient management. The clinician needs to evaluate several key issues prior to institution of antiretroviral regimen including the correct stage of starting the treatment and the kind of regimen to initiate. In addition to various disease related factors, it is also critical to assess the patient's general condition including nutritional status, presence of co-morbidities and mental preparedness prior to starting the therapy. The patients need to develop an overall understanding of the treatment and its benefits and the importance of lifelong adherence to the drugs. The presence of special situations like pediatric age, older patients, pregnancy, lactation and presence of opportunistic infections also require modification of the therapy. This review briefly summarizes issues relevant to the clinician prior to the initiation of antiretroviral therapy.

Outcomes among HIV-1 infected individuals first starting antiretroviral therapy with concurrent active TB or other AIDS-defining disease

Background

Tuberculosis (TB) is common among HIV-infected individuals in many resource-limited countries and has been associated with poor survival. We evaluated morbidity and mortality among individuals first starting antiretroviral therapy (ART) with concurrent active TB or other AIDS-defining disease using data from the “Prospective Evaluation of Antiretrovirals in Resource-Limited Settings” (PEARLS) study.

Methods

Participants were categorized retrospectively into three groups according to presence of active confirmed or presumptive disease at ART initiation: those with pulmonary and/or extrapulmonary TB (“TB” group), those with other non-TB AIDS-defining disease (“other disease”), or those without concurrent TB or other AIDS-defining disease (“no disease”). Primary outcome was time to the first of virologic failure, HIV disease progression or death. Since the groups differed in characteristics, proportional hazard models were used to compare the hazard of the primary outcome among study groups, adjusting for age, sex, country, screening CD4 count, baseline viral load and ART regimen.

Results

31 of 102 participants (30%) in the “TB” group, 11 of 56 (20%) in the “other disease” group, and 287 of 1413 (20%) in the “no disease” group experienced a primary outcome event (p = 0.042). This difference reflected higher mortality in the TB group: 15 (15%), 0 (0%) and 41 (3%) participants died, respectively (p<0.001). The adjusted hazard ratio comparing the “TB” and “no disease” groups was 1.39 (95% confidence interval: 0.93–2.10; p = 0.11) for the primary outcome and 3.41 (1.72–6.75; p<0.001) for death.

Conclusions

Active TB at ART initiation was associated with increased risk of mortality in HIV-1 infected patients.

Antiretroviral therapy for prevention of HIV and tuberculosis: a promising intervention but not a panacea

The demonstration of the efficacy of antiretroviral therapy (ART) for HIV prevention in heterosexual HIV serodiscordant couples has resulted in the call for widespread implementation of "Treatment as Prevention" (TasP) to confront the challenge of continued transmission of HIV. In addition, evidence of the possible effect of use of ART on decreasing the incidence of tuberculosis (TB) in persons living with HIV has also contributed further enthusiasm. Mathematical modeling studies evaluating the potential impact of TasP on the trajectory of the HIV and TB epidemics have inspired discussions about a possible future without AIDS. We present the evidence regarding the effect of ART on the incidence of HIV and TB, benefits and risks associated with embracing TasP, and the need for multicomponent prevention strategies and for further research to generate empiric data on the effect of TasP on HIV and TB at a population level.

Predictors of death during tuberculosis treatment in TB/HIV co-infected patients in Malaysia

Background

Mortality among TB/HIV co-infected patients is still high particularly in developing countries. This study aimed to determine the predictors of death in TB/HIV co-infected patients during TB treatment.

Methods

We reviewed medical records at the time of TB diagnosis and subsequent follow-up of all newly registered TB patients with HIV co-infection at TB clinics in the Institute of Respiratory Medicine and three public hospitals in the Klang Valley between January 2010 and September 2010. We reviewed these medical records again twelve months after their initial diagnosis to determine treatment outcomes and survival. We analysed using Kaplan-Meier and conducted multivariate Cox proportional hazards analysis to identify predictors of death during TB treatment in TB/HIV co-infected patients.

Results

Of the 227 patients studied, 53 (23.3%) had died at the end of the study with 40% of deaths within two months of TB diagnosis. Survival at 2, 6 and 12 months after initiating TB treatment were 90.7%, 82.8% and 78.8% respectively. After adjusting for other factors, death in TB/HIV co-infected patients was associated with being Malay (aHR 4.48; 95%CI 1.73-11.64), CD4 T-lymphocytes count < 200 cells/µl (aHR 3.89; 95% CI 1.20-12.63), three or more opportunistic infections (aHR 3.61; 95% CI 1.04-12.55), not receiving antiretroviral therapy (aHR 3.21; 95% CI 1.76-5.85) and increase per 10³ total white blood cell count per microliter (aHR 1.12; 95% CI 1.05-1.20)

Conclusion

TB/HIV co-infected patients had a high case fatality rate during TB treatment. Initiation of antiretroviral therapy in these patients can improve survival by restoring immune function and preventing opportunistic infections.

Initiation of antiretroviral therapy in HIV-infected tuberculosis patients in rural Kenya: an observational study

OBJECTIVE

To provide information on the effect of timing of antiretroviral therapy (ART) initiation on outcomes of TB infection in real-life, non-clinical trial, rural settings in sub-Saharan Africa.

METHODS

We conducted an observational cohort study of all HIV-infected TB patients presenting to a rural hospital in Kenya between 2005 and 2009. We analysed the association between timing of initiation of ART and mortality, using a Cox regression survival analysis, adjusted for measured confounders.

RESULTS

A total of 404 antiretroviral-naïve HIV/TB coinfected patients were included in the study. Initiation of ART during the first 8 weeks of TB treatment (early group) was not associated with changes in mortality at 1 year compared with initiation of ART after 8 weeks (late group) [Hazard Ratio (HR) = 0.74 (Confidence Interval (CI), 0.33-1.64, P = 0.46]. In patients with baseline CD4 counts ≤50 cells/μl, there was a significant reduction in mortality in the early group compared with the late group (HR = 0.20; 95% CI, 0.042-0.99; P = 0.049). In patients with a CD4 count >50 cells/μl, there was no significant difference between early and late groups (HR 1.79; 95% CI, 0.64-5.03; P = 0.27).

CONCLUSIONS

We found that in HIV/TB coinfected patients in rural Kenya, early ART initiation (within 8 weeks) was associated with reduced mortality in those with CD4 counts ≤50 cells/μl. In patients with CD4 counts >50 cells/μl, there was no association seen between timing of ART and mortality.

Comparison of treatment outcomes of new smear-positive pulmonary tuberculosis patients by HIV and antiretroviral status in a TB/HIV clinic, Malawi

Background

Smear-positive pulmonary TB is the most infectious form of TB. Previous studies on the effect of HIV and antiretroviral therapy on TB treatment outcomes among these highly infectious patients demonstrated conflicting results, reducing understanding of important issues.

Methods

All adult smear-positive pulmonary TB patients diagnosed between 2008 and 2010 in Malawi’s largest public, integrated TB/HIV clinic were included in the study to assess treatment outcomes by HIV and antiretroviral therapy status using logistic regression.

Results

Of 2,361 new smear-positive pulmonary TB patients, 86% had successful treatment outcome (were cured or completed treatment), 5% died, 6% were lost to follow-up, 1% failed treatment, and 2% transferred-out. Overall HIV prevalence was 56%. After adjusting for gender, age and TB registration year, treatment success was higher among HIV-negative than HIV-positive patients (adjusted odds ratio 1.49; 95% CI: 1.14–1.94). Of 1,275 HIV-infected pulmonary TB patients, 492 (38%) received antiretroviral therapy during the study. Pulmonary TB patients on antiretroviral therapy were more likely to have successful treatment outcomes than those not on ART (adjusted odds ratio : 1.83; 95% CI: 1.29–2.60).

Conclusion

HIV co-infection was associated with poor TB treatment outcomes. Despite high HIV prevalence and the integrated TB/HIV setting, only a minority of patients started antiretroviral therapy. Intensified patient education and provider training on the benefits of antiretroviral therapy could increase antiretroviral therapy uptake and improve TB treatment success among these most infectious patients.

When to start antiretroviral therapy during tuberculosis treatment?

PURPOSE OF REVIEW

Effective treatment exists for tuberculosis (TB) and for HIV, but treating both diseases simultaneously presents several challenges. This review assesses the evidence for the timing of antiretroviral therapy (ART) initiation in patients coinfected with TB.

RECENT FINDINGS

Published evidence clearly demonstrates that TB-HIV integration is essential for improved survival, but the question of when to start ART during TB treatment is more complex. Five randomized controlled trials assessed this question: four trials showed no difference in the incidence rates of AIDS or death between TB patients initiating ART within 2 months compared to later during TB therapy, while one trial showed a significant survival gain with ART initiation within 2 weeks of TB therapy start. All five studies found improved AIDS-free survival with earlier ART initiation in TB patients with low CD4 T-cell counts, except among patients with TB meningitis. The survival benefit was, however, accompanied by increased immune reconstitution inflammatory syndrome events.

SUMMARY

The trial data support the World Health Organization recommendations on when to start ART in TB-HIV coinfected patients including earlier ART initiation in severely immune-compromised patients. However, several challenges remain in integrating TB and HIV treatment in public healthcare services. Additional research on timing of ART is needed for patients with drug-resistant and extrapulmonary TB, notably TB meningitis.

Determinants of unsuccessful tuberculosis treatment outcomes in Malaysian HIV-infected patients

OBJECTIVES

To determine predictors of unsuccessful treatment in HIV-infected tuberculosis (TB) patients.

METHODS

We reviewed medical records at the time of TB diagnosis and subsequent follow-up of all registered TB patients with HIV co-infection at TB clinics in the Institute of Respiratory Medicine and three public hospitals in Malaysia between January 2010 and September 2010. We reviewed these medical records again twelve months after their initial diagnosis to determine treatment outcomes. Multiple logistic regression was conducted to identify risk factors for unsuccessful TB treatment.

RESULTS

Among the 219 patients analyzed, 53.4% achieved successful outcomes (cure, completed treatment) while 46.6% of patients had unsuccessful outcomes (default, treatment failure, died). After adjusting for other factors, unsuccessful outcome was associated with intravenous drug use (OR 2.72; 95% CI 1.44-5.16), not receiving antiretroviral therapy (OR 5.10; 95% CI 2.69-9.69), lymphadenopathy (OR 2.01; 95% CI 1.09-3.72) and low serum albumin (OR 4.61; 95% CI 1.73-12.27).

CONCLUSION

Anti-retroviral treatment must be provided to all HIV-infected tuberculosis patients. Good immune and nutritional status needs to be assured in all HIV-infected tuberculosis patients. More studies are required in intravenous drug users to understand why tuberculosis treatment outcomes are poor in this group.

Optimal timing for initiation of highly active antiretroviral therapy in treatment-naïve human immunodeficiency virus-1-infected individuals presenting with AIDS-defining diseases: the experience of the PISCIS Cohort

In this prospective, multicentre cohort study, we analysed specific prognostic factors and the impact of timing of highly active antiretroviral therapy (HAART) on disease progression and death among 625 human immunodeficiency virus (HIV)-1-infected, treatment-naïve patients diagnosed with an AIDS-defining disease. HAART was classified as early (<30 days) or late (30-270 days). Deferring HAART was significantly associated with faster progression to a new AIDS-defining event/death overall (p 0.009) and in patients with Pneumocystis jiroveci pneumonia (p 0.017). In the multivariate analysis, deferring HAART was associated with a higher risk of a new AIDS-defining event/death (p 0.002; hazard ratio 1.83; 95% CI 1.25-2.68). Other independent risk factors for poorer outcome were baseline diagnosis of AIDS-defining lymphoma, age >35 years, and low CD4(+) count (<50 cells/μL).

Factors associated with survival among adults with HIV-associated TB in Guangxi, China: a retrospective cohort study

Aim: Although China has the second highest burden of TB in the world and faces a burgeoning HIV epidemic, the epidemiology and 12-month clinical outcomes of HIV-infected TB patients have not previously been reported. Methods: We reviewed records of all HIV-infected adults diagnosed with culture-confirmed TB from four HIV clinics in Guangxi, China from August 2006 to December 2008. Factors associated with patients’ survival within 12 months after TB diagnosis were evaluated in Cox proportional hazards models. Results: Among the 201 patients included, 47 (23%) died within 12 months. Median CD4 count at TB diagnosis was 37 cells/mm3 (interquartile range: 16–102). Receiving HAART (adjusted hazard ratio [AHR]: 4.2; 95% CI: 1.6–10.8), receiving TB treatment (AHR: 9.0; 95% CI: 1.5–53.5) and baseline BMI ≥ 18.5 (AHR: 8.4; 95% CI: 1.9–35.8) were independently associated with survival. Among 171 (85%) patients who received TB treatment, receiving HAART (HR: 5.1; 95% CI: 2.4–10.7) was the only factor significantly associated with survival. Conclusion: HIV-infected Chinese patients diagnosed with TB in Guangxi are at high risk of death within 12 months, a risk that is strongly mitigated by antiretroviral therapy. Improving survival from HIV-associated TB in China will require the integration of TB and HIV programs to improve access to treatment for both diseases.

[The impact of HIV infection on childhood tuberculosis in Yaounde, Cameroon]

OBJECTIVES

To define the prevalence of HIV infection in childhood tuberculosis and investigate its impact on the clinical presentation, radiographic findings and outcomes among children suffering from tuberculosis in Yaounde.

METHODS

The medical records of 101 children aged less than 15years, hospitalized with tuberculosis in the chest clinic of the Yaounde Jamot Hospital between January 2005 and June 2010, were retrospectively reviewed.

RESULTS

Twenty-five (24.8%) of the 101 patients were HIV positive. The occurrence of concomitant intrathoracic and extrathoracic tuberculosis was more frequently observed in HIV infected children (P=0.021). Parenchymal pulmonary lesions were bilateral in 20 (90.9%) of the HIV infected children against 31 (56.1%) in the non-infected children (P=0.003). Cavitating lesions were present in 49.1% of the cases in HIV negative group versus 13.6% in HIV positive group (P=0.004), but sub-group analysis restricted to those with confirmed tuberculosis no longer showed a significant difference. The success rate of treatment was 78.9% among HIV negative patients and 56% among HIV positive patients (P=0.024).

CONCLUSION

HIV infection modifies the clinical presentation and radiographic features of tuberculosis in children. The treatment success rate is lower in HIV positive children, indicating a stricter medical supervision of these children and more targeted education of their parents.

Projecting the benefits of antiretroviral therapy for HIV prevention: the impact of population mobility and linkage to care

BACKGROUND

Recent mathematical models suggested that frequent human immunodeficiency virus (HIV) testing with immediate initiation of antiretroviral therapy (ART) to individuals with a positive test result could profoundly curb transmission. The debate about ART as prevention has focused largely on parameter values. We aimed to evaluate structural assumptions regarding linkage to care and population mobility, which have received less attention.

METHODS

We modified the linkage structure of published models of ART as prevention, such that individuals who decline initial testing or treatment do not link to care until late-stage HIV infection. We then added population mobility to the models. We populated the models with demographic, clinical, immigration, emigration, and linkage data from a South African township.

RESULTS

In the refined linkage model, elimination of HIV transmission (defined as an incidence of <0.1%) did not occur by 30 years, even with optimistic assumptions about the linkage rate. Across a wide range of estimates, models were more sensitive to structural assumptions about linkage than to parameter values. Incorporating population mobility further attenuated the reduction in incidence conferred by ART as prevention.

CONCLUSIONS

Linkage to care and population mobility are critical features of ART-as-prevention models. Clinical trials should incorporate relevant data on linkage to care and migration to evaluate the impact of this strategy.

HIV & immune reconstitution inflammatory syndrome (IRIS)

Antiretroviral therapy (ART) initiation in HIV-infected patients leads to recovery of CD4+T cell numbers and restoration of protective immune responses against a wide variety of pathogens, resulting in reduction in the frequency of opportunistic infections and prolonged survival. However, in a subset of patients, dysregulated immune response after initiation of ART leads to the phenomenon of immune reconstitution inflammatory syndrome (IRIS). The hallmark of the syndrome is paradoxical worsening of an existing infection or disease process or appearance of a new infection/disease process soon after initiation of therapy. The overall incidence of IRIS is unknown, but is dependent on the population studied and the burden of underlying opportunistic infections. The immunopathogenesis of the syndrome is unclear and appears to be result of unbalanced reconstitution of effector and regulatory T-cells, leading to exuberant inflammatory response in patients receiving ART. Biomarkers, including interferon-γ (INF-γ), tumour necrosis factor-α (TNF-α), C-reactive protein (CRP) and inter leukin (IL)-2, 6 and 7, are subject of intense investigation at present. The commonest forms of IRIS are associated with mycobacterial infections, fungi and herpes viruses. Majority of patients with IRIS have a self-limiting disease course. ART is usually continued and treatment for the associated condition optimized. The overall mortality associated with IRIS is low; however, patients with central nervous system involvement with raised intracranial pressures in cryptococcal and tubercular meningitis, and respiratory failure due to acute respiratory distress syndrome (ARDS) have poor prognosis and require aggressive management including corticosteroids. Paradigm shifts in management of HIV with earlier initiation of ART is expected to decrease the burden of IRIS in developed countries; however, with enhanced rollout of ART in recent years and the enormous burden of opportunistic infections in developing countries like India, IRIS is likely to remain an area of major concern.

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.

Updating our understanding of pulmonary disease associated with HIV infection

The introduction of highly active antiretroviral therapy (HAART) has resulted in a reduction of opportunistic infections associated with cellular and humoral immunosuppression. However, what is still unclear is the impact of HAART on the development of other diseases not associated with AIDS, such as lung cancer and COPD. The aim of this paper is to review the most innovative and relevant aspects of lung pathology in patients infected with HIV.

Risk factors for mortality among HIV-positive patients with and without active tuberculosis in Dar es Salaam, Tanzania

BACKGROUND

The aim of this study was to describe risk factors for mortality and clinical characteristics of HIV-infected patients with and without tuberculosis (TB) coinfection.

METHODS

A cohort of HIV-infected patients with CD4(+) T-cell counts of ≤200 cells/μl was recruited, consisting of 255 HIV-infected patients without active TB and 231 patients with active TB. All received a well-supervised treatment with an efavirenz-based HAART, and those coinfected with TB received appropriate anti-TB treatment. They were followed up for 48 weeks after HAART initiation.

RESULTS

Common presenting symptoms in HIV-only patients were fever (36.5%), headache (34.5%), skin rash (34.5%) and weight loss (32%), while in HIV-TB patients the symptoms were weight loss (58%), cough (57.6%), night sweats (44.6%) and fever (34.2%). HIV-TB patients had significantly lower body mass index, Karnofsky scores and haemoglobin levels compared to those infected with HIV only, despite similar baseline CD4(+) T-cell counts. Overall, 12 (4.7%) HIV patients developed TB and 7 (3%) HIV-TB patients had worsening of their TB symptoms during the study period. Mortality was similar in the two groups, being 10.9% (16 deaths per 100 person years) and 11.3% (17 deaths per 100 person years) in HIV-only and HIV-TB patients, respectively. Overall, more males (13.1%) died compared to females (9.6%). Predictors of mortality were presence of oral candidiasis, Kaposi's sarcoma, low Karnofsky score, and low baseline white blood cell and CD4(+) T-cell counts.

CONCLUSIONS

The outcomes following well-supervised treatment of HIV-TB patients are similar to those in patients with HIV alone. Predictors of mortality were those of advanced disease.

HIV-1 and bacterial pneumonia in the era of antiretroviral therapy

Community-acquired pneumonia affects approximately 4 million people in the United States, with 40,000 deaths per year. The incidence is increased about 35-fold in HIV-infected individuals, and this rate has decreased since the antiretroviral era has begun. Bacterial pneumonia has decreased from 5 to 20 cases per 100 person-years to less than 1 to 5 cases per 100 person-years in the era of antiretroviral therapy. HIV-1 infection impairs the function of neutrophils in the lung and infects CD4⁺ cells and alveolar macrophages. Opportunistic infections dramatically increase local HIV replication in the lung cells, especially alveolar macrophages and CD4⁺ cells. This enhanced replication increases viral mutations and provides opportunities for viral escape from latent reservoirs. Mortality is increased with more comorbidities in this highly susceptible population. Immunization with vaccines is recommended, especially pneumococcal vaccines, although the vaccine itself may stimulate viral replication. Recent studies show that the lower respiratory tract is a microbial reservoir in HIV-infected individuals rather than being a sterile environment, as originally thought. This may provide new opportunities for preventing opportunistic infections in HIV-infected subjects. Bacterial pneumonia presents an ongoing challenge in these high-risk individuals, particularly in studying the functions of the innate and acquired immune response.