Tuberculosis and HIV co-infection. PLoS Pathog. 2012;8:e1002464. [PMID: 22363214 PMCID: PMC3280977 DOI: 10.1371/journal.ppat.1002464]

A Spatiotemporal Analysis of HIV-Associated Mortality in Rural Western Kenya 2011-2015

Background:

Reliable data on the HIV epidemic is critical for the measurement of the impact of HIV response and for the implementation of further interventions.

Methods:

We used mortality data from the Kombewa health and demographic surveillance systems (HDSS) from January 1, 2011 to December 31, 2015 to examine the space–time pattern of HIV-associated mortality. HIV mortality rate was calculated per 1000 persons living with HIV (for comparison with regional and national averages) and per 1000 person-years (p-y) for comparison with data from other HDSS sites. We used the Optimized Hot Spot Analysis to examine whether HIV-associated deaths would form statistically significant local aggregation in the 5-year period. P-value of <0.05 and <0.01 was considered significant.

Results:

The HIV-associated mortality rate over the 5-year period was 9.8 per 1000 persons living with HIV (PLHIV). Mortality declined from 11.6 per 1000 PLHIV in 2011 to 7.3 per 1000 PLHIV by the end of 2015. The rates of HIV were highest among infants [hazard ratio (HR) = 2.39 (<0.001)]. Tuberculosis mortality rates were highest in the age group 5–14 years [HR = 2.29 (0.002)] and the age group 50–64 years [HR = 1.18 (0.531)]. The overall trend in HIV-associated mortality showed a decline from 1.8 per 1000 p-y in 2011 to 1.3 per 1000 p-y by the end of 2015. The hotspot analysis showed that 20.0% of the study area (72 km²) was detected as hotspots (Z = 2.382–3.143, P ≤ 0.001) and 4.2% of the study area as cold spots (15 km²).

Conclusions:

HIV attributable death in the HDSS population is substantial, although it is lower than both the national and the regional estimates.

Population Structure and Implications on the Genetic Architecture of HIV-1 Phenotypes Within Southern Africa

The interesting history of Southern Africa has put the region in the spotlight for population medical genetics. Major events including the Bantu expansion and European colonialism have imprinted unique genetic signatures within autochthonous populations of Southern Africa, this resulting in differential allele frequencies across the region. This genetic structure has potential implications on susceptibility and resistance to infectious diseases such as human immunodeficiency virus (HIV) infection. Southern Africa is the region affected worst by HIV. Here, we discuss advances made in genome-wide association studies (GWAS) of HIV-1 in the past 12 years and dissect population diversity within Southern Africa. Our findings accentuate that a plethora of factors such as migration, language and culture, admixture, and natural selection have profiled the genetics of the people of Southern Africa. Genetic structure has been observed among the Khoe-San, among Bantu speakers, and between the Khoe-San, Coloureds, and Bantu speakers. Moreover, Southern African populations have complex admixture scenarios. Few GWAS of HIV-1 have been conducted in Southern Africa, with only one of these identifying two novel variants (HCG22rs2535307 and CCNG1kgp22385164) significantly associated with HIV-1 acquisition and progression. High genetic diversity, multi-wave genetic mixture and low linkage disequilibrium of Southern African populations constitute a challenge in identifying genetic variants with modest risk or protective effect against HIV-1. We therefore posit that it is compelling to assess genome-wide contribution of ancestry to HIV-1 infection. We further suggest robust methods that can pin-point population-specific variants that may contribute to the control of HIV-1 in Southern Africa.

Marine Natural Products and Drug Resistance in Latent Tuberculosis

Pyrazinamide (PZA) is the only drug for the elimination of latent Mycobacterium tuberculosis (MTB) isolates. However, due to the increased number of PZA-resistance, the chances of the success of global TB elimination seems to be more prolonged. Recently, marine natural products (MNPs) as an anti-TB agent have received much attention, where some compounds extracted from marine sponge, Haliclona sp. exhibited strong activity under aerobic and hypoxic conditions. In this study, we screened articles from 1994 to 2019 related to marine natural products (MNPs) active against latent MTB isolates. The literature was also mined for the major regulators to map them in the form of a pathway under the dormant stage. Five compounds were found to be more suitable that may be applied as an alternative to PZA for the better management of resistance under latent stage. However, the mechanism of actions behind these compounds is largely unknown. Here, we also applied synthetic biology to analyze the major regulatory pathway under latent TB that might be used for the screening of selective inhibitors among marine natural products (MNPs). We identified key regulators of MTB under latent TB through extensive literature mining and mapped them in the form of regulatory pathway, where SigH is negatively regulated by RshA. PknB, RshA, SigH, and RNA polymerase (RNA-pol) are the major regulators involved in MTB survival under latent stage. Further studies are needed to screen MNPs active against the main regulators of dormant MTB isolates. To reduce the PZA resistance burden, understanding the regulatory pathways may help in selective targets of MNPs from marine natural sources.

Tuberculosis and HIV co-infection in Congolese children: risk factors of death

INTRODUCTION

Human immunodeficiency virus (HIV) and tuberculosis (TB) are the leading causes of death from infectious disease worldwide. The prevalence of HIV among children with TB in moderate to high prevalence countries ranges between 10% and 60%. This study aimed to determine the prevalence of HIV infection among children treated for TB in Directly Observed Treatment Short-Course (DOTS) clinics in Lubumbashi and to identify risk of death during this co-infection.

METHODS

This is a cross-sectional study of children under-15, treated for tuberculosis from January 1, 2013 to December 31, 2015. Clinical, paraclinical and outcome data were collected in 22 DOTS of Lubumbashi. A statistical comparison was made between dead and survived HIV-infected TB children. We performed the multivariate analyzes and the significance level set at p-value <0.05.

RESULTS

A total of 840 children with TB were included. The prevalence of HIV infection was 20.95% (95% CI: 18.34-23.83%). The mortality rate was higher for HIV-infected children (47.73%) compared to HIV-uninfected children (17.02%) (p<0.00001). Age <5 years (aOR=6.50 [1.96-21.50]), a poor nutritional status (aOR=23.55 [8.20-67.64]), and a negative acid-fast bacilli testing (aOR=4.51 [1.08-18.70]) were associated with death during anti-TB treatment.

CONCLUSION

TB and HIV co-infection is a reality in pediatric settings in Lubumbashi. High mortality highlights the importance of early management.

Strongyloides stercoralis infection in human immunodeficiency virus-infected patients and related risk factors: A systematic review and meta-analysis

Strongyloidiasis is caused by nematode infections of the genus Strongyloides, mainly Strongyloides stercoralis, and affects tens of millions of people around the world. S. stercoralis hyperinfection and disseminated strongyloidiasis are unusual but potentially fatal conditions mostly due to Gram-negative bacteremia and sepsis, primarily affecting immunocompromised patients. Infections with immunosuppressive viruses such as human immunodeficiency virus (HIV) and Human T-cell leucemia virus type 1 (HTLV-1) have been reported as risk factors for strongyloidiasis. Hyperinfection syndrome has been described in HIV-positive patients following the use of corticosteroids or during immune reconstitution inflammatory syndrome (IRIS). In this research, we conducted a global systematic review and meta-analysis to assess the seroprevalence and odds ratios (ORs) of S. stercoralis infections in HIV-infected patients. A total of 3,649 records were screened, 164 studies were selected and evaluated in more detail, and 94 studies were included in the meta-analysis. The overall pooled prevalence of S. stercoralis infection in HIV positive patients was 5.1% (CI95%: 4%-6.3%), and a meta-analysis on six studies showed that with a pooled OR of 1.79 (CI95%: 1.18%-2.69%) HIV-positive men are at a higher risk of S. stercoralis infections (p < .0052) compared to HIV positive women.

Resuscitation of Dormant "Non-culturable" Mycobacterium tuberculosis Is Characterized by Immediate Transcriptional Burst

Under unfavorable conditions such as host immune responses and environmental stresses, human pathogen Mycobacterium tuberculosis may acquire the dormancy phenotype characterized by "non-culturability" and a substantial decrease of metabolic activity and global transcription rates. Here, we found that the transition of M. tuberculosis from the dormant "non-culturable" (NC) cells to fully replicating population in vitro occurred not earlier than 7 days after the start of the resuscitation process, with predominant resuscitation over this time interval evidenced by shortening apparent generation time up to 2.8 h at the beginning of resuscitation. The early resuscitation phase was characterized by constant, albeit low, incorporation of radioactive uracil, indicating de novo transcription immediately after the removal of the stress factor, which resulted in significant changes of the M. tuberculosis transcriptional profile already after the first 24 h of resuscitation. This early response included transcriptional upregulation of genes encoding enzymes of fatty acid synthase system type I (FASI) and type II (FASII) responsible for fatty acid/mycolic acid biosynthesis, and regulatory genes, including whiB6 encoding a redox-sensing transcription factor. The second resuscitation phase took place 4 days after the resuscitation onset, i.e., still before the start of active cell division, and included activation of central metabolism genes encoding NADH dehydrogenases, ATP-synthases, and ribosomal proteins. Our results demonstrate, for the first time, that the resuscitation of dormant NC M. tuberculosis is characterized by immediate activation of de novo transcription followed by the upregulation of genes controlling key metabolic pathways and then, cell multiplication.

Structural, functional and biological insights into the role of Mycobacterium tuberculosis VapBC11 toxin-antitoxin system: targeting a tRNase to tackle mycobacterial adaptation

Toxin–antitoxin (TA) systems are involved in diverse physiological processes in prokaryotes, but their exact role in Mycobacterium tuberculosis (Mtb) virulence and in vivo stress adaptation has not been extensively studied. Here, we demonstrate that the VapBC11 TA module is essential for Mtb to establish infection in guinea pigs. RNA-sequencing revealed that overexpression of VapC11 toxin results in metabolic slowdown, suggesting that modulation of the growth rate is an essential strategy for in vivo survival. Interestingly, overexpression of VapC11 resulted in the upregulation of chromosomal TA genes, suggesting the existence of highly coordinated crosstalk among TA systems. In this study, we also present the crystal structure of the VapBC11 heterooctameric complex at 1.67 Å resolution. Binding kinetic studies suggest that the binding affinities of toxin–substrate and toxin–antitoxin interactions are comparable. We used a combination of structural studies, molecular docking, mutational analysis and in vitro ribonuclease assays to enhance our understanding of the mode of substrate recognition by the VapC11 toxin. Furthermore, we have also designed peptide-based inhibitors to target VapC11 ribonuclease activity. Taken together, we propose that the structure-guided design of inhibitors against in vivo essential ribonucleases might be a novel strategy to hasten clearance of intracellular Mtb.

Prospects for a vaccine to prevent HIV-related tuberculosis

PURPOSE OF REVIEW

To outline the need for a new tuberculosis (TB) vaccine; challenges for induction of vaccine-mediated protection in HIV-infected persons; and recent advances in clinical development.

RECENT FINDINGS

HIV has a detrimental effect on T-cell function, polarization and differentiation of Mycobacterium tuberculosis (Mtb)-specific T cells, Mtb antigen presentation by dendritic cells, and leads to B-cell and antibody-response deficiencies. Previous observations of protection against TB disease in HIV-infected persons by Mycobacterium obuense suggest that an effective vaccine against HIV-related TB is feasible. Studies of inactivated mycobacterial, viral-vectored and protein subunit vaccines reported lower immune responses in HIV-infected relative to HIV-uninfected individuals, which were only partially restored with antiretroviral therapy. Bacille Calmette Guerin (BCG) revaccination of HIV-uninfected adolescents recently showed moderate efficacy against sustained Mtb infection, but live mycobacterial vaccines have an unfavorable risk profile for HIV-infected persons. Ongoing trials of inactivated mycobacterial and protein-subunit vaccines in HIV-uninfected, Mtb-infected adults may be more relevant for protection of HIV-infected populations in TB endemic countries.

SUMMARY

New TB vaccine candidates have potential to protect against HIV-related TB, through vaccination prior to or after HIV acquisition, but this potential may only be realized after efficacy is demonstrated in HIV-uninfected populations, with or without Mtb infection.

Survival Time and Prognostic Factors of Mortality among Patients with Acquired Immunodeficiency Syndrome in North-East Peninsular Malaysia

BACKGROUND

Death resulting from the acquired immunodeficiency syndrome (AIDS) is a worldwide concern. This study is aimed at determining the overall median survival time, and the prognostic factors of mortality among AIDS-infected patients in North-East Peninsular Malaysia.

METHODS

In 2018, a retrospective cohort study stretching from January to April was conducted. This study involved a review of data obtained from the National AIDS Registry. A total of 1,073 AIDS cases diagnosed from 1 January 2010 to 31 December 2014 were selected, and follow-up procedures were conducted until 31 March 2015 (a 3-month follow-up). The Kaplan-Meier plot and Cox's proportional hazard regression were used for data analyses.

RESULTS

564 (52.5%) patients died due to AIDS, while the remaining 509 (47.4%) were censored. The overall median survival time was 11 months. The probability of survival in 1-year, 2-year, 3-year, 4-year and 5-year periods were 49.1%, 47.8%, 47.3%, 47.0% and 46.7%, respectively. Multiple Cox regression revealed that the significant prognostic factors were age 30-49 years [adjusted hazard ratio (Adj. HR) 1.57; 95% CI: 1.14, 2.16; P = 0.006], male (Adj. HR 1.39; 95% CI: 1.07, 1.79; P = 0.012), unemployed (Adj. HR 1.40; 95% CI: 1.12, 1.75; P = 0.003) and HIV-TB co-infection (Adj. HR 1.78; 95% CI: 1.37, 2.31; P < 0.001).

CONCLUSION

The overall median survival time among AIDS patients in North-East Peninsular Malaysia was revealed to be short, in comparison to the other studies. The chances for survival can be improved with more emphasis on early detection (to ensure early treatment) and social support, particularly for HIV-TB co-infected patients, as well as for younger and unemployed patients.

Targeting HIV-TB coinfection by developing novel piperidin-4-substituted imines: Design, synthesis, in vitro and in silico studies

Tuberculosis is the "Achilles heel" of the human immunodeficiency (HIV) ministration. HIV-positive people are 16-27 times more prone to contract tuberculosis. But the adverse interaction between antiretroviral drugs and antitubercular drugs has made it necessary to look for a single drug regimen for HIV-TB coinfection. Piperidine derivatives have been reported as anti-HIV and anti-TB agents. This inspired us to design, synthesize, and characterize a series of 3,5-bis(furan-2-ylmethylidene)-piperidin-4-substituted imines (R1-R25) and these were further screened for in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv and anti-HIV activity. Molecular docking studies showed energetically favorable binding interactions with both EACP reductase (1ZID.pdb) and reverse-transcriptase (1REV.pdb) targets. The compounds R7, R12, R17, R18, R19, R20 were found to be more potent as anti-TB agents than ethambutol (MIC 3.125 μg/ml). Compound R7 was found to be moderately active with an IC50 of 2.1 ± 0.04 μM in multicycle infection assays, in comparison with the standard drug, zidovudine (IC50  = 5.7 ± 0.04 nM), used as anti-HIV drug. The cytotoxicity assay was done on Vero, MT-2, and TZM-bl cells to assess the safety of these compounds and they were found to be safe. From the above results, R7 seems to be a promising lead for anti-HIV and anti-TB activity.

HIV/AIDS length of stay in Portugal under financial constraints: a longitudinal study for public hospitals, 2009-2014

BACKGROUND

The global financial crisis and the economic and financial adjustment programme (EFAP) forced the Portuguese government to adopt austerity measures, which also included the health sector. The aim of this study was to analyse factors associated with HIV/AIDS patients' length of stay (LOS) among Portuguese hospitals, and the potential impact of the EFAP measures on hospitalizations among HIV/AIDS patients.

METHODS

Data used in this analysis were collected from the Portuguese database of Diagnosis Related Groups (DRG). We considered only discharges classified under MCD 24 created for patients with HIV infection. A total of 20,361 hospitalizations occurring between 2009 and 2014 in 41 public hospitals were included in the analysis. The outcome was the number of days between hospital admission and discharge dates (LOS). Hierarchical Poisson regression model with random effects was used to analyse the relation between LOS and patient, treatment and setting characteristics. To more effectively analyse the impact of the EFAP implementation on HIV/AIDS hospitalizations, yearly variables, as well as a variable measuring hospitals' financial situation (current ratio) was included.

RESULTS

For the 5% level, having HIV/AIDS as the principal diagnosis, the number of secondary diagnoses, the number of procedures, and having tuberculosis have a positive impact in HIV/AIDS LOS; while being female, urgent admission, in-hospital mortality, pneumocystis pneumonia, hepatitis C, and hospital's current ratio contribute to the decrease of LOS. Additionally, LOS between 2010 and 2014 was significantly shorter in comparison to 2009. Differences in LOS across hospitals are significant after controlling for these variables.

CONCLUSION

Following the EFAP, a number of cost-containment measures in the health sector were implemented. Results from our analysis suggest that the implementation of these measures contributed to a significant decrease is LOS among HIV/AIDS patients in Portuguese hospitals.

Lung Tissue Resident Memory T-Cells in the Immune Response to Mycobacterium tuberculosis

Despite widespread BCG vaccination and effective anti-TB drugs, Tuberculosis (TB) remains the leading cause of death from an infectious agent worldwide. Several recent publications give reasons to be optimistic about the possibility of a more effective vaccine, but the only full-scale clinical trial conducted failed to show protection above BCG. The immunogenicity of vaccines in humans is primarily evaluated by the systemic immune responses they generate, despite the fact that a correlation between these responses and protection from TB disease has not been demonstrated. A novel approach to tackling this problem is to study the local immune responses that occur at the site of TB infection in the human lung, rather than those detectable in blood. There is a growing understanding that pathogen specific T-cell immunity can be highly localized at the site of infection, due to the existence of tissue resident memory T-cells (Trm). Notably, these cells do not recirculate in the blood and thus may not be represented in studies of the systemic immune response. Here, we review the potential role of Trms as a component of the TB immune response and discuss how a better understanding of this response could be harnessed to improve TB vaccine efficacy.

Self-awareness control effect of cooperative epidemics on complex networks

Coinfection mechanism is a common interacting mode between multiple diseases in real spreading processes, where the diseases mutually increase their susceptibility, and has aroused widespread studies in network science. We use the bond percolation theory to characterize the coinfection model under two self-awareness control strategies, including immunization strategy and quarantine strategy, and to study the impacts of the synergy effect and control strategies on cooperative epidemics. We find that strengthening the synergy effect can reduce the epidemic threshold and enhance the outbreak size of coinfected networks. On Erdős-Rényi networks, the synergy effect will induce a crossover phenomenon of phase transition, i.e., make the type of phase transition from being continuous to discontinuous. Self-awareness control strategies play a non-negligible role in suppressing cooperative epidemics. In particular, increasing immunization or the quarantine rate can enhance the epidemic threshold and reduce the outbreak size of cooperative epidemics, and lead to a crossover phenomenon of transition from being discontinuous to continuous. The impact of quarantine strategy on cooperative epidemics is more significant than the immunization strategy, which is verified on scale-free networks.

Health Considerations for HIV-Infected International Travelers

PURPOSE OF THE REVIEW

International travel continues to steadily increase, including leisure travel, travel to one's country of origin to visit friends and relatives, travel for service work, and business travel. Travelers with HIV may have an increased risk for travel-associated infections. The pre-travel medical consultation is an important means of assessing one's risk for travel-related health issues. The aim of this review is to provide an update on key health considerations for the HIV-infected traveler.

RECENT FINDINGS

Like all travelers, the HIV-infected traveler should adhere to behavioral precautions, including safety measures with food and water consumption, safe sexual practices, and arthropod bite avoidance. HIV is a risk factor for venous thromboembolism and patients should be educated regarding this risk. Most pre-travel vaccines are safe and immunogenic in HIV-infected individuals, though live vaccines should be avoided in patients with low CD4 counts. Malaria chemoprophylaxis is strongly recommended in patients with HIV traveling to endemic areas and no significant interactions exist between the commonly used prophylactic anti-malarial agents and anti-retroviral therapy (ART). Travelers with HIV, particularly those who are not on ART or who have low CD4 cell counts, may have increased risk for tuberculosis, malaria, enteric infections, visceral leishmaniasis, American trypanosomiasis, and endemic mycoses such as histoplasmosis, talaromycosis, and coccidioidomycosis. The immune status of the HIV-infected traveler should be assessed prior to travel along with the duration, itinerary, and activities planned during travel in order to carefully consider individual risk for travel-related health issues.

Serum and Bronchoalveolar Lavage Fluid 25(OH)Vitamin D3 Levels in HIV-1 and Tuberculosis: A Cross-Sectional Study from a Tertiary Care Center in North India

BACKGROUND

Vitamin D is an immunomodulator, and its deficiency is associated with Tuberculosis (TB) infection. Bronchoalveolar lavage fluid (BALF) is a rich milieu of macrophages that form the first line of defense against invading TB bacilli. As there is an increased prevalence of vitamin D deficiency in TB and human immunodeficiency virus-1 (HIV-1) subjects, we intend exploring the possibility of a localized deficiency of vitamin D metabolites in BALF of these patients.

OBJECTIVE

The primary objective was to assess the level of 25D3 in serum and BALF of subjects and look for a significant difference among patients and controls. The secondary objective was to find a correlation between serum and BALF 25D3 levels.

METHODS

We performed a cross-sectional study with subjects divided into four groups: Controls (group 1), HIV positive without active TB (group 2), active TB without HIV (group 3), and HIV-TB coinfection (group 4). BALF and serum 25D3 levels were compared between the groups.

RESULTS

Among the 149 (an immunomodulator) successive subjects enrolled, there were 40 subjects in group 1 (HIV-TB-), 48 in group 2 (HIV+TB-), 37 in group 3 (HIV-TB+), and 24 in group 4 (HIV+TB+). Females constituted 31.6% of the study subjects. In groups 3 and 4, there were significantly lower serum 25D3 levels compared to group 1 (p-value group 3: 0.002; group 4: 0.012). In groups 2, 3, and 4, there were significantly lower BALF 25D3 levels compared to group 1 (p-value group 2: 0.000; group 3: 0.000; group 4: 0.001). There was a significant correlation between serum and BALF 25D3 levels (Spearman's rank correlation coefficient 0.318, p-value = 0.0001).

CONCLUSION

Lower levels of serum and BALF 25D3 were observed in HIV, TB, and HIV-TB coinfected patients. Localized deficiency of vitamin D metabolites might be associated with increased vulnerability to TB infection.

Comparative Docking Studies: A Drug Design Tool for Some Pyrazine- Thiazolidinone Based Derivatives for Anti-HIV Activity

Conclusion:

Most of the molecules have shown good dock score and binding energy with anti-HIV receptors but Molecules 13 and 14 have potential to act as anti-tubercular and Anti HIV and hence can be further explored for dual activity.</P>

Transforming Growth Factor-β Suppresses Interleukin (IL)-2 and IL-1β Production in HIV-Tuberculosis Co-Infection

Interleukin (IL)-1β and IL-2 play important roles in protective immune responses against Mycobacterium tuberculosis (Mtb) infection. Information on the factors that regulate the production of these cytokines in the context of human immunodeficiency virus and latent tuberculosis infection (LTBI) or active tuberculosis (TB) disease is limited. In this study, we compared the production of these cytokines by peripheral blood mononuclear cells (PBMCs) from HIV^- and HIV⁺ individuals with latent and active Tuberculosis infection in response to Mtb Antigen 85A. PBMCs from HIV⁺ LTBI⁺ and HIV⁺ active TB patients produced low IL-1β, IL-2 but high transforming growth factor beta (TGF-β) compared to healthy controls. CD4⁺ T cells from HIV patients expressed low retinoic acid-related orphan receptor gamma (RORγ), and high suppressors of cytokine signaling-3 (SOCS-3). Active TB infection in HIV⁺ individuals further inhibited antigen-specific IL-1β and IL-2 production compared with those with LTBI. Neutralization of TGF-β restored IL-1β and IL-2 levels and lowered SOCS-3 production by CD4⁺ T cells. We hypothesize that high TGF-β in HIV patients could be a reason for defective Mtb-specific IL-1β, IL-2 production and activation of latent TB in HIV. Coupling anti-TGF-β antibodies with antiretroviral therapy treatment might increase T cell function to boost the immune system for effective clearance of Mtb.

Expansion of a novel lead targeting M. tuberculosis DHFR as antitubercular agents

A series of 1-(1-benzyl-2-methyl-5-((1-phenyl-1H-1,2,3-triazol-4-yl)methoxy)-1H-indol-3-yl)ethanone and ethyl 1-benzyl-2-methyl-5-((1-phenyl-1H-1,2,3-triazol-4-yl)methoxy)-1H-indole-3-carboxylate derivatives were designed based on bioisosteric replacement of previously reported antitubercular agent (IND-07). Twenty ligands were successfully synthesized and some of them were found to have good in vitro activity (MIC < 10 μM) against the H₃₇Rv strain of Mycobacterium tuberculosis. Among these compounds, KC-08 and KC-11 inhibited Mtb-DHFR with 4- and 18-fold selectivity for Mtb-DHFR over h-DHFR, respectively. Compound KC-11 display acceptable ADME, and better pharmacokinetic profiles than IND-07. Docking studies were performed to predict the binding mode of the compounds within the active site of Mtb-DHFR and h-DHFR. The results of our study suggest that compound KC-11 may serve as a valuable lead for the design and development of selective inhibitors of Mtb-DHFR with potential therapeutic application in tuberculosis.

A Bibliometric Analysis on Tuberculosis Research of Korea from 1979 to 2017

BACKGROUND

The prevalence, incidence, and mortality rates of tuberculosis (TB) have declined steadily in Korea since 1965. This study aimed to identify the characteristics and provide quantitative analysis of published medical literatures on TB written by researchers based in Korea.

METHODS

We conducted a systematic literature search via the Web of Science database for articles in Science Citation Index (Expanded) journals, on TB, and published by researchers based in Korea, from inception to 2017. All articles were analyzed by publication year, publishing journal, article type, study design, research institutes, and research funds.

RESULTS

During the study period, we identified 1,101 articles and included them for analysis. The first was published in 1979, while 105 were published in 2017. Between 1979 and 2017, the compound annual growth rate of TB articles by researchers based in Korea was 13.0%. Among 1,101 articles, 682 (61.9%) were clinical research and 383 (34.8%) were basic research. Studies with cross-sectional design were the most common type among the clinical research, while biochemistry was the most common field among the basic research. The number of articles dealing with diagnostics or treatment has increased significantly, although the number of articles on vaccines, and on operational and public health, has only a slight increase. The Ministry of Health and Welfare of Korea funded studies yielding 178 (20.1%) articles.

CONCLUSION

Articles on TB, especially those on clinical aspects, and published by researchers based in Korea have been increasing rapidly since 1979.

Immunometabolic Signatures Predict Risk of Progression to Active Tuberculosis and Disease Outcome

There remains a pressing need for biomarkers that can predict who will progress to active tuberculosis (TB) after exposure to Mycobacterium tuberculosis (MTB) bacterium. By analyzing cohorts of household contacts of TB index cases (HHCs) and a stringent non-human primate (NHP) challenge model, we evaluated whether integration of blood transcriptional profiling with serum metabolomic profiling can provide new understanding of disease processes and enable improved prediction of TB progression. Compared to either alone, the combined application of pre-existing transcriptome- and metabolome-based signatures more accurately predicted TB progression in the HHC cohorts and more accurately predicted disease severity in the NHPs. Pathway and data-driven correlation analyses of the integrated transcriptional and metabolomic datasets further identified novel immunometabolomic signatures significantly associated with TB progression in HHCs and NHPs, implicating cortisol, tryptophan, glutathione, and tRNA acylation networks. These results demonstrate the power of multi-omics analysis to provide new insights into complex disease processes.

BCG Vaccination Prevents Reactivation of Latent Lymphatic Murine Tuberculosis Independently of CD4+ T Cells

Tuberculosis (TB) is a major global public health problem causing significant mortality and morbidity. In addition to ~10.4 million cases of active TB annually, it is estimated that about two billion people are latently infected with Mycobacterium tuberculosis (Mtb), the causative agent of TB. Reactivation of latent Mtb infection is the leading cause of death in patients with immunodeficiency virus (HIV) infection. The low efficiency of the only licensed anti-TB vaccine, Bacille Calmette–Guérin (BCG) to reduce pulmonary TB in adults contributes to this problem. Here we investigated if vaccination with conventional BCG or the genetically modified experimental BCGΔBCG1419c strain can prevent reactivation of latent lymphatic TB in a mouse model of induced reactivation, following the depletion of CD4⁺ T cells, as it occurs in HIV⁺ individuals. Vaccination with conventional BCG or BCGΔBCG1419c prevented reactivation of Mtb from the infected lymph node and the systemic spread of Mtb to spleen and lung. Prevention of reactivation was independent of vaccination route and was accompanied by reduced levels of circulating inflammatory cytokines and the absence of lung pathology. Our results demonstrate that vaccine-induced CD4⁺ T cells are not essential to prevent reactivation of latent lymphatic murine TB, and highlight the need to better understand how non-CD4⁺ immune cell populations participate in protective immune responses to control latent TB.

Socio-economic status and risk of tuberculosis: a case-control study of HIV-infected patients in Asia

SETTING

Tuberculosis (TB) is the most common human immunodeficiency virus (HIV) related opportunistic infection and cause of acquired immune-deficiency syndrome related death. TB often affects those from a low socio-economic background.

OBJECTIVE

To assess the socio-economic determinants of TB in HIV-infected patients in Asia.

DESIGN

This was a matched case-control study. HIV-positive, TB-positive cases were matched to HIV-positive, TB-negative controls according to age, sex and CD4 cell count. A socio-economic questionnaire comprising 23 questions, including education level, employment, housing and substance use, was distributed. Socio-economic risk factors for TB were analysed using conditional logistic regression analysis.

RESULTS

A total of 340 patients (170 matched pairs) were recruited, with 262 (77.1%) matched for all three criteria. Pulmonary TB was the predominant type (n = 115, 67.6%). The main risk factor for TB was not having a university level education (OR 4.45, 95%CI 1.50-13.17, P = 0.007). Burning wood or coal regularly inside the house and living in the same place of origin were weakly associated with TB diagnosis.

CONCLUSIONS

These data suggest that lower socio-economic status is associated with an increased risk of TB in Asia. Integrating clinical and socio-economic factors into HIV treatment may help in the prevention of opportunistic infections and disease progression.

How Viral and Intracellular Bacterial Pathogens Reprogram the Metabolism of Host Cells to Allow Their Intracellular Replication

Viruses and intracellular bacterial pathogens (IBPs) have in common the need of suitable host cells for efficient replication and proliferation during infection. In human infections, the cell types which both groups of pathogens are using as hosts are indeed quite similar and include phagocytic immune cells, especially monocytes/macrophages (MOs/MPs) and dendritic cells (DCs), as well as nonprofessional phagocytes, like epithelial cells, fibroblasts and endothelial cells. These terminally differentiated cells are normally in a metabolically quiescent state when they are encountered by these pathogens during infection. This metabolic state of the host cells does not meet the extensive need for nutrients required for efficient intracellular replication of viruses and especially IBPs which, in contrast to the viral pathogens, have to perform their own specific intracellular metabolism to survive and efficiently replicate in their host cell niches. For this goal, viruses and IBPs have to reprogram the host cell metabolism in a pathogen-specific manner to increase the supply of nutrients, energy, and metabolites which have to be provided to the pathogen to allow its replication. In viral infections, this appears to be often achieved by the interaction of specific viral factors with central metabolic regulators, including oncogenes and tumor suppressors, or by the introduction of virus-specific oncogenes. Less is so far known on the mechanisms leading to metabolic reprogramming of the host cell by IBPs. However, the still scant data suggest that similar mechanisms may also determine the reprogramming of the host cell metabolism in IBP infections. In this review, we summarize and compare the present knowledge on this important, yet still poorly understood aspect of pathogenesis of human viral and especially IBP infections.

Advances in the understanding of Mycobacterium tuberculosis transmission in HIV-endemic settings

Tuberculosis claims more human lives than any other infectious disease. This alarming epidemic has fuelled the development of novel antimicrobials and diagnostics. However, public health interventions that interrupt transmission have been slow to emerge, particularly in HIV-endemic settings. Transmission of tuberculosis is complex, involving various environmental, bacteriological, and host factors, among which concomitant HIV infection is important. Preventing person-to-person spread is central to halting the epidemic and, consequently, tuberculosis transmission is now being studied with renewed interest. In this Series paper, we review recent advances in the understanding of tuberculosis transmission, from the view of source-case infectiousness, inherent susceptibility of exposed individuals, appending tools for predicting risk of disease progression, the biophysical nature of the contagion, and the environments in which transmission occurs and is sustained in populations. We focus specifically on how HIV infection affects these features with a view to describing novel transmission blocking strategies in HIV-endemic settings.

Persistent spatial patterns of interacting contagions

The spread of infectious diseases, rumors, fashions, and innovations are complex contagion processes, embedded in network and spatial contexts. While the studies in the former context are intensively expanded, the latter remains largely unexplored. In this paper, we investigate the pattern formation of an interacting contagion, where two infections, A and B, interact with each other and diffuse simultaneously in space. The contagion process for each follows the classical susceptible-infected-susceptible kinetics, and their interaction introduces a potential change in the secondary infection propensity compared to the baseline reproduction number R_{0}. We show that the nontrivial spatial infection patterns arise when the susceptible individuals move faster than the infected and the interaction between the two infections is neither too competitive nor too cooperative. Interestingly, the system exhibits pattern hysteresis phenomena, i.e., quite different parameter regions for patterns exist in the direction of increasing or decreasing R_{0}. Decreasing R_{0} reveals remarkable enhancement in contagion prevalence, meaning that the eradication becomes difficult compared to the single-infection or coinfection without space. Linearization analysis supports our observations, and we have identified the required elements and dynamical mechanism, which suggests that these patterns are essentially Turing patterns. Our work thus reveals new complexities in interacting contagions and paves the way for further investigation because of its relevance to both biological and social contexts.

Predictors of mortality among intensive care unit patients coinfected with tuberculosis and HIV

Objective:

To identify factors predictive of mortality in patients admitted to the ICU with tuberculosis (TB)/HIV coinfection in the Manaus, Amazon Region.

Methods:

This was a retrospective cohort study of TB/HIV coinfected patients over 18 years of age who were admitted to an ICU in the city of Manaus, Brazil, between January of 2011 and December of 2014. Sociodemographic, clinical, and laboratory variables were assessed. To identify factors predictive of mortality, we employed a Cox proportional hazards model.

Results:

During the study period, 120 patients with TB/HIV coinfection were admitted to the ICU. The mean age was 37.0 ± 11.7 years. Of the 120 patients evaluated, 94 (78.3%) died and 62 (66.0%) of those deaths having occurred within the first week after admission. Data on invasive mechanical ventilation (IMV) and ARDS were available for 86 and 67 patients, respectively Of those 86, 75 (87.2%) underwent IMV, and, of those 67, 48 (71.6%) presented with ARDS. The factors found to be independently associated with mortality were IMV (p = 0.002), hypoalbuminemia (p = 0.013), and CD4 count < 200 cells/mm³ (p = 0.002).

Conclusions:

A high early mortality rate was observed among TB/HIV coinfected ICU patients. The factors predictive of mortality in this population were IMV, hypoalbuminemia, and severe immunosuppression.

Quality of life among HIV-tuberculosis co-infected patients

Background:

India is the world's third leading country in terms of people living with human deficiency virus (HIV) (2.1 million) with 0.4 million deaths due to HIV-associated tuberculosis (TB). Physical and mental stress degrades the quality of life (QOL) in these patients. Studies have been done in HIV patients but very few on HIV-TB co-infected patients. Our study aims at assessing and comparing the QOL in HIV patients with and without TB.

Materials and Methods:

It was a cross-sectional study done at Antiretroviral Treatment Center of KMC, Mangalore and District Wenlock Hospital, Mangalore, over 6 months. A sample size was 104. Semi-structured questionnaire to collect clinico-demographic data, World Health Organization QOL (WHOQOL)-HIV BREF to assess the QoL, and Beck's Depression Inventory Scale (Physical health, psychological well-being, social relationship, environmental health, level of independence, and spiritual health) to identify depression were used. The Cronbach's alpha was used to measure the internal consistency for each domain of the WHOQOL-HIV instrument.

Results:

HIV-TB co-infected patients had a lower mean score in all domains as compare to only HIV patients, suggesting that HIV-TB co-infected patients had a poor QOL (P < 0.05). Internal consistency of each domain was good (α >0.7).

Conclusion:

To improve the QOL in HIV patients, it is important to identify the determinants of QOL and work toward its improvement.

Disability and health outcomes - from a cohort of people on long-term anti-retroviral therapy

Human-immunodeficiency virus (HIV)/Acquired immunodeficiency Syndrome (AIDS) remains a major health problem in South Africa - even after two decades since the introduction of antiretroviral therapy (ART). Long-term survival with HIV is associated with new health-related issues and a risk of functional limitation/disability. The aim of this study was to assess functional limitation associated with HIV/AIDS among people living with HIV (PLHIV) in South Africa. This study is a cross-sectional survey using a cohort in an urban area in Gauteng province, South Africa. Data were collected using questionnaires through an interview process. The information collected included aspects such as demographics, livelihood, the state of mental and physical health, adherence and disability. A total of 1044 participants with an average age of 42 ± 12 years were included in the study, with 51.9% of the participants reporting functional limitations (WHODAS ≥ 2). These were reported mainly in the domains of participation (40.2%) and mobility (38.7%). In addition, adherence to ART, symptoms of poor physical health and depression were strongly associated with their functional limitations/disability. HIV as a chronic disease is associated with functional limitations that are not adequately addressed and pose a risk of long-term disability and negative adherence outcomes. Therefore, wellness for PLHIV/AIDS needs to include interventions that can prevent and manage disability.

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

OBJECTIVE

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

DESIGN

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

SETTING

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

PARTICIPANTS

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

RESULTS

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

CONCLUSION

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

Point-of-Care Ultrasound for Extrapulmonary Tuberculosis in India: A Prospective Cohort Study in HIV-Positive and HIV-Negative Presumptive Tuberculosis Patients

Diagnosing extrapulmonary tuberculosis (EPTB) is challenging. Point-of-care ultrasound (POCUS) for human immunodeficiency virus (HIV)-associated EPTB is applied in sub-Saharan Africa. This study aimed at evaluating the applicability of POCUS for diagnosing EPTB in HIV-positive and HIV-negative presumptive tuberculosis (TB) patients in India, a country of moderate relative TB and HIV burden. Presumptive TB patients at Kasturba Hospital, Manipal, India, prospectively underwent POCUS evaluating for pericardial, pleural and ascitic effusion, abdominal lymphadenopathy, and hepatic and splenic microabscesses. Findings were correlated with TB category (confirmed TB, clinical TB, unlikely TB), HIV status, and discharge diagnoses. A total of 425 patients underwent POCUS; 81 (20%) were HIV-positive. POCUS findings were more common in HIV/TB coinfected patients than in HIV-positive patients with unlikely TB (24/40 (60%) versus 9/41 (22%), P < 0.001). Abdominal lymphadenopathy and splenic microabscesses were strongly associated with TB in HIV-positive patients (P = 0.002 and P = 0.001). POCUS findings did not correlate with TB in HIV-negative patients; a third of HIV-negative patients with unlikely TB and POCUS findings had cancer, another third other infectious diseases. Sonographic findings were common in HIV-positive and HIV-negative presumptive TB patients. POCUS was a useful bedside test for the detection of HIV-associated EPTB. In HIV-negative patients, POCUS detected features associated with EPTB but also of malignancy and other infectious diseases.

Bacteria-Host Interactions in Multiple Sclerosis

Multiple sclerosis (MS) is caused by a complex interaction of genetic and environmental factors. Numerous causative factors have been identified that play a role in MS, including exposure to bacteria. Mycobacteria, Chlamydia pneumoniae, Helicobacter pylori, and other bacteria have been proposed as risk factors for MS with different mechanisms of action. Conversely, some pathogens may have a protective effect on its etiology. In terms of acquired immunity, molecular mimicry has been hypothesized as the mechanism by which bacterial structures such as DNA, the cell wall, and intracytoplasmic components can activate autoreactive T cells or produce autoantibodies in certain host genetic backgrounds of susceptible individuals. In innate immunity, Toll-like receptors play an essential role in combating invading bacteria, and their activation leads to the release of cytokines or chemokines that mediate effective adaptive immune responses. These receptors may also be involved in central nervous system autoimmunity, and their contribution depends on the infection site and on the pathogen. We have reviewed the current knowledge of the influence of bacteria on MS development, emphasizing the potential mechanisms of action by which bacteria affect MS initiation and/or progression.

Computational studies on N-phenyl pyrrole derivatives as MmpL3 inhibitors in Mycobacterium tuberculosis

The fight against tuberculosis (TB) is a time immemorial one and the emergence of new drug resistant strains of Mycobacterium tuberculosis keeps throwing new challenges to the scientific community immersed in finding mechanisms to control this dreaded disease. Computer aided drug designing (CADD) is one of the several approaches that can assist in identifying the potent actives against Mycobacterium. In this work, a series of 109 known Mycobacterial membrane proteins large 3 (MmpL3) inhibitors were pooled and atom based 3D QSAR analysis was performed to understand the structural features essential for inhibitory activity against the MmpL3, known to be a key player in transporting substances critical for cell wall integrity of Mycobacterium. The data set employed was randomly split into training set and test set molecules. The training set of 74 molecules was used to derive CoMFA and CoMSIA models that were statistically reliable (CoMFA: q²_loo = 0.53; r²_ncv = 0.93 and CoMSIA: q²_loo = 0.60; r²_ncv = 0.93). The derived models also exhibited good external predictive ability (CoMFA: r²_pred = 0.78 and CoMSIA: r²_pred = 0.79). The results are quite encouraging and information derived from these analyses was applied to design new molecules. The designed molecule showed appreciable predicted activity values and reasonably good ADMET profile. The strategy used in designing new molecules can be pursued in the hunt for new chemical entities targeting MmpL3, expanding the existing arsenal against TB.

Human Immunodeficiency Virus and Tuberculosis Coinfection in a Tertiary Hospital in Southern Brazil: Clinical Profile and Outcomes

Worldwide, the convergence of tuberculosis (TB) and human immunodeficiency virus type 1 (HIV-1) infection epidemics is a public health challenge. In Brazil, TB is the leading cause of death by infectious disease in people living with HIV (PLWH). This study aimed to report the clinical, demographic, epidemiological, and laboratory data for TB in PLWH. This cross-sectional study involved a retrospective analysis of data for patients with TB/HIV coinfection who attended from 2006 to 2015 through a review of medical records. A total of 182 patients were identified, of whom 12 were excluded. Patients were divided according to whether they had pulmonary tuberculosis (PTB; n = 48; 28%) or extrapulmonary tuberculosis (EPTB; n = 122; 72%). The diagnosis was laboratory confirmed in 75% of PTB patients and 78.7% of EPTB patients. The overall 1-year mortality rate was 37.6%, being 22.9% in PTB patients and 69% in EPTB patients; 84% of these deaths were TB-related. The CD4+ count and disseminated TB were independent risk factors for death. The frequency of resistance among Mycobacterium tuberculosis (MTB) isolates was 14%. TB in PLWH is associated with high morbidity and mortality, and severe immunosuppression is a risk factor for death. Appropriate measures for early TB detection should reduce the case fatality rate in high-burden settings.

Pulmonary immunization with a recombinant influenza A virus vaccine induces lung-resident CD4+ memory T cells that are associated with protection against tuberculosis

The lung is the primary site of infection with the major human pathogen, Mycobacterium tuberculosis. Effective vaccines against M. tuberculosis must stimulate memory T cells to provide early protection in the lung. Recently, tissue-resident memory T cells (T_RM) were found to be phenotypically and transcriptional distinct from circulating memory T cells. Here, we identified M. tuberculosis-specific CD4⁺ T cells induced by recombinant influenza A viruses (rIAV) vaccines expressing M. tuberculosis peptides that persisted in the lung parenchyma with the phenotypic and transcriptional characteristics of T_RMs. To determine if these rIAV-induced CD4⁺ T_RM were protective independent of circulating memory T cells, mice previously immunized with the rIAV vaccine were treated with the sphingosine-1-phosphate receptor modulator, FTY720, prior to and during the first 17 days of M. tuberculosis challenge. This markedly reduced circulating T cells, but had no effect on the frequency of M. tuberculosis-specific CD4⁺ T_RMs in the lung parenchyma or their cytokine response to infection. Importantly, mice immunized with the rIAV vaccine were protected against M. tuberculosis infection even when circulating T cells were profoundly depleted by the treatment. Therefore, pulmonary immunization with the rIAV vaccine stimulates lung-resident CD4⁺ memory T cells that are associated with early protection against tuberculosis infection.

Long-term safety and immunogenicity of the M72/AS01E candidate tuberculosis vaccine in HIV-positive and -negative Indian adults: Results from a phase II randomized controlled trial

OBJECTIVES

To assess the long-term safety and immunogenicity of the M72/ Adjuvant System (AS01E) candidate tuberculosis (TB) vaccine up to 3 years post-dose 2 (Y3) in human immunodeficiency virus (HIV)-positive (HIV+) and HIV-negative (HIV-) Indian adults.

METHODS

This phase II, double-blind, randomised, controlled clinical trial (NCT01262976) was conducted at YRG CARE Medical Centre, in Chennai, India, between January 2011 and June 2015.Three cohorts (HIV+ participants stable on antiretroviral therapy [ART; HIV+ART+], HIV+ ART-naïve [HIV+ART-], and HIV- participants) were randomised (1:1) to receive 2 doses of M72/AS01E (M72/AS01E groups) or saline (control groups) 1 month apart and were followed up toY3. Latent TB infection was assessed at screening using an interferon-gamma (IFN-γ) release assay (IGRA). Safety and immunogenicity results up to Y1 post-vaccination were reported elsewhere. Here, we report serious adverse events (SAEs), humoral and cell-mediated immune (CMI) responses to M72 recorded at Y2 and Y3.

RESULTS

Of 240 enrolled and vaccinated participants, 214 completed the long-term follow-up part of the study.In addition to SAEs previously described, between Y1 and Y2 1 M72/AS01E recipient in the HIV+ART+ cohort reported 2 SAEs (sinus cavernous thrombosis and gastroenteritis) that were not considered as causally related to the study vaccine.Vaccination elicited persistent humoral immune responses against M72. At Y3, seropositivity rates were 97.1%, 66.7%, and 97.3% and geometric mean concentrations (GMCs) were 22.0  ELISA units (EU)/mL, 4.9 EU/mL, and 24.3 EU/mL in the HIV+ART+, HIV+ART-, and HIV- cohorts, respectively. Humoral immune response was lowest in the HIV+ART- cohort.In M72/AS01E recipients, no notable decrease in the frequency of M72-specific CD4 T-cells expressing ≥2 immune markers among interleukin-2 (IL-2), IFN-γ, tumour necrosis factor alpha (TNF-α) and CD40 ligand (CD40L) was observed at Y3 post-vaccination. Median values (interquartile range) of 0.35% (0.13-0.49), 0.05% (0.01-0.10), and 0.15% (0.09-0.22) were recorded in the HIV+ART+, HIV+ART- and HIV- cohorts, respectively. CD4 T-cell response was lowest in the HIV+ART- cohort.No CD8 T-cell response was observed.

CONCLUSION

The cellular and humoral immune responses induced by M72/AS01E in HIV+ and HIV- adults persisted up to Y3 post-vaccination. No safety concerns were raised regarding administration of M72/AS01E to HIV+ adults.

CLINICAL TRIAL REGISTRATION

NCT01262976 (www.clinicaltrials.gov).

Sex differences in tuberculosis

Tuberculosis is the most prevalent bacterial infectious disease in humans and the leading cause of death from a single infectious agent, ranking above HIV/AIDS. The causative agent, Mycobacterium tuberculosis, is carried by an estimated two billion people globally and claims more than 1.5 million lives each year. Tuberculosis rates are significantly higher in men than in women, reflected by a male-to-female ratio for worldwide case notifications of 1.7. This phenomenon is not new and has been reported in various countries and settings over the last century. However, the reasons for the observed gender bias are not clear, potentially highly complex and discussed controversially in the literature. Both gender- (referring to sociocultural roles and behavior) and sex-related factors (referring to biological aspects) likely contribute to higher tuberculosis rates in men and will be discussed.

Characterising antibody avidity in individuals of varied Mycobacterium tuberculosis infection status using surface plasmon resonance

There is increasing evidence supporting a role for antibodies in protection against tuberculosis (TB), with functional antibodies being described in the latent state of TB infection. Antibody avidity is an important determinant of antibody-mediated protection. This study characterised the avidity of antibodies against Ag85A, an immunodominant Mycobacterium tuberculosis (M.tb) antigen and constituent of several anti-TB vaccine candidates, in individuals of varied M.tb infection status. Avidity of Ag85A specific antibodies was measured in 30 uninfected controls, 34 individuals with latent TB infection (LTBI) and 75 active pulmonary TB (APTB) cases, employing the more commonly used chaotrope-based dissociation assays, and surface plasmon resonance (SPR). Chaotrope-based assays indicated that APTB was associated with a higher antibody avidity index compared to uninfected controls [adjusted geometric mean ratio (GMR): 1.641, 95% confidence interval (CI): 1.153, 2.337, p = 0.006, q = 0.018] and to individuals with LTBI [adjusted GMR: 1.604, 95% CI: 1.282, 2.006, p < 0.001, q <0.001]. SPR assays showed that APTB was associated with slower dissociation rates, an indication of higher avidity, compared to uninfected controls (adjusted GMR: 0.796, 95% CI: 0.681, 0.932, p = 0.004, q = 0.012) and there was also weak evidence of more avid antibodies in the LTBI compared to the uninfected controls (adjusted GMR: 0.871, 95% CI: 0.763, 0.994, p = 0.041, q = 0.123). We found no statistically significant differences in anti-Ag85A antibody avidity between the APTB and LTBI groups. This study shows that antibodies of increased avidity are generated against a principle vaccine antigen in M.tb infected individuals. It would be important to determine whether TB vaccines are able to elicit a similar response. Additionally, more research is needed to determine whether antibody avidity is important in protection against infection and disease.

EXPERIENCING SYNDEMIC: DISENTANGLING THE BIOSOCIAL COMPLEXITY OF TUBERCULOSIS THROUGH QUALITATIVE RESEARCH

Tuberculosis (TB) remains a major global public health problem that has become a crisis fuelled by HIV and the increasing occurrence of antimicrobial resistance. What has been termed the biosocial nature of TB challenges effective control of the disease. Yet, biosocial interactions involved in the persistence of TB in diverse settings are difficult to systematically account for. The recently developed framework of syndemics provides a way to capture how complex health problems result from the interactions between diseases such as HIV and TB, and harmful social conditions such as unemployment, malnutrition and substance abuse. This article advances the syndemics scholarship by examining health conditions that cluster together with TB in the Russian Federation, by eliciting a set of social processes that precipitate this clustering and exacerbate health outcomes, and by analysing interactions between these health conditions and social processes. To provide an account of this complexity, the article takes a qualitative approach and draws on the perspectives and experiences of people with TB. The results demonstrate emergence of a syndemic of stress, substance abuse, TB and HIV that is sustained by poverty, occupational insecurity, marginalization and isolation. Frictions between the narrow focus of the health care system on TB and the wider syndemic processes in which the lives of many persons with TB are embedded, contribute to poorer health outcomes and increase the risks of developing drug resistance. Finally, the article argues that the large-scale and impersonal forces become embodied as individual pathology through the crucial interface of the ways in which persons experience and make sense of these forces and pathologies. Qualitative research is needed for the adequate analysis of this biosocial complexity in order to provide a solid basis for responses to TB-centred syndemics in various settings.

Clinical and experimental research in antituberculosis drug-induced hepatotoxicity: a review

Drug-induced liver injury is the common adverse effect seen in patients receiving antituberculosis drugs (ATDs). There are several risk factors associated with the development of hepatotoxicity in such patients. Though there have been appreciable efforts taken by carrying out studies investigating the efficacy of several natural and synthetic compounds in minimising this effect, the only choice available for clinicians is withdrawal of drugs. This review would give a precise idea of ATD-induced hepatotoxicity, its underlying mechanisms and alternative therapies for the same.

Adherence to antiretroviral therapy and correlation with adverse effects and coinfections in people living with HIV/AIDS in the municipality of Goiás State

INTRODUCTION

Acquired immunodeficiency syndrome is an advanced stage of a human immunodeficiency virus infection. The antiretroviral therapy aims to improve the life quality of HIV patients and a good adherence is essential for a better prognosis. This study aimed to evaluate the adherence of human immunodeficiency virus/acquired immunodeficiency syndrome patients to antiretroviral therapy recommended by the Brazilian health system in Anápolis/Goiás, and correlate the level of adherence with sociodemographic data and clinical-laboratory variables.

METHODS

Adherence to antiretroviral therapy was assessed using the Questionnaire for Evaluation of Adherence to Antiretroviral Therapy. The sociodemographic data were collected using a standardized questionnaire and the clinical-laboratory records were reviewed.

RESULTS

Among 220 patients included, 59% (129/220) were men and the average age was 41 years. Infection was acquired primarily through sexual contact (92%, 202/220), and 69% (152/220) of the patients were heterosexual. Approximately 86% (188/220) of the patients had good or strict adherence to antiretroviral therapy. In our study, the use of illicit drugs was associated with low adherence to antiretroviral therapy (p=0.0004), and no significant association was observed between adherence levels and other sociodemographic data (p>0.05). The logistic regression indicated that adverse effects (p=0.0018) and sexual orientation (p=0.0152) were associated with the level of adherence to antiretroviral therapy. Patients with good or strict adherence had higher CD4+T lymphocyte count (p<0.0001) and undetectable viral load (p<0.0001). Patients with low adherence (14%, 32/220) had higher frequency of adverse events (p=0.0009). The frequency of coinfections was 25% (55/220), with syphilis and tuberculosis being the most common coinfections.

CONCLUSIONS

Adherence was related to use of illicit drugs, adverse effects, and sexual orientation.

Time taken to link newly identified HIV positive clients to care following a home-base index case HIV testing: Experience from two provinces in Zimbabwe

Background

Homebased index case HIV testing (HHTC) has shown higher uptake and good yield than traditional HIV testing methods. World Health Organization has called for increased operational research to evaluate HIV care processes particularly linkage to care. In this paper, we present project results of the time taken to link newly identified PLHIV to care after HHTC in the Manicaland and Midlands provinces of Zimbabwe.

Methods

We retrospectively reviewed community-facility referral data from the Zimbabwe HIV Care and Treatment project for newly diagnosed PLHIV for the period March–September 2016. A referral slip was given to a client after receiving a positive HIV results and was presented and filed upon reaching a health facility. In July 2016, the project started working with trained expert clients to assist with linkage to care. Data was entered in a spreadsheet and then imported for descriptive statistical analysis with EpiInfo^TM Version 7.2.0.1. Odd ratios were used to identify factors associated with linkage to care within seven days.

Results

Out of 1004 newly identified PLHIV between March and September 2016, 650 (64.7%) were linked to care. The median time taken to be linked to care was four days (Interquartile range 19 days). Overall, 63.1% (410) of PLHIV were linked to care within seven days of diagnosis and 85% within 30 days. PLHIV were more likely to be linked to care within seven days of diagnosis between July and September 2016 (OR = 4.1; p< 0.001), a period when ZHCT started working with expert clients to support linkage to care.

Conclusion

HHTC resulted in almost 63% of newly diagnosed PLHIV being linked into care within seven days, and 85% within 30 days. Linkage to care within seven days was significantly associated with the period of engaging expert clients in the project. We recommend community based HIV testing programs to work with expert clients to ensure timely linkages of new PLHIV.

BIOIMPEDANCE MARKERS AND TUBERCULOSIS OUTCOME AMONG HIV-INFECTED PATIENTS

Background

The changes in body composition markers (weight, fat mass, lean mass, and BMI) over time can be associated with TB treatment outcome among HIV-infected patients. The aim of this study was to investigate whether changes in fat mass and lean mass were associated with the treatment response among patients with HIV infection and pulmonary tuberculosis.

Materials and Methods

This was a prospective cohort study. Data from HIV-infected patients commencing TB therapy were analyzed. This included body weight measurement using bioimpedance equipment at baseline, one month, and two months after starting TB treatment.

Results

The study was conducted in 125 patients, 17 patients (13.6%) died during treatment, of which 5 died during the first month of treatment, 4 during the second month and 8 after the second month. The group of patients with good response, increased their weight by 1.3 kg (p <0.001) at the end of the first month of TB treatment and 2.6 kg in the second month (p <0.001), and body fat increase was 1.2 Kg (p <0.001) and 2.3 kg (p <0.001), the first and second month respectively. The group of patients who died had lost 2.1 kg fat mass after the first month (p <0.001) and 3.7 kg in the second month (p <0.001).

Conclusions

Our results show that the weight change during TB treatment (increased fat mass) helps us predict therapeutic response. Weight loss during the first month of starting therapy should be evaluated thoroughly to identify the probable cause of treatment failure.

Knowledge, Attitude, and Practices Regarding HIV and TB Among Homeless People in Tehran, Iran

BACKGROUND

Homeless people are at high risk of HIV and tuberculosis (TB) infection due to living in poor sanitary conditions and practicing high-risk behavior. The aim of this study is to assess the knowledge, attitude, and practice (KAP) of homeless people in Tehran regarding TB and HIV.

METHODS

Using a convenience sampling, we performed a cross-sectional study on homeless people in Tehran from June to August 2012. Participants aged 18-60 years having at least 10 days of homelessness in the preceding month to the study period were included. All required data were collected through face-to-face interviews conducted using a researcherdesigned questionnaire. Each score in KAP of TB and HIV was separately divided by the maximum score and multiplied by 100 to attain percentage scores. The mean scores were compared using analysis of variance (ANOVA) and student's t test. A Tukey test was used for post hoc analysis and two-by-two comparisons.

RESULTS

In this study, 593 participants consisting of 513 men and 80 women were included. The mean age of the participants was 41.74 ± 0.45 years. Moreover, the total mean score of KAP toward HIV was 79.24 (95% CI: 77.36, 81.12), 57.13 (95% CI: 55.12, 59.14), and 21.14 (95% CI: 18.35, 23.93), respectively. The total mean score of knowledge and practice regarding TB was 62.04 (95% CI: 59.94, 64.14) and 42.57 (95% CI: 40.36, 44.78), respectively.

CONCLUSION

Although a relatively acceptable knowledge was detected in this high-risk population, practices regarding TB and HIV showed some weaknesses. Developing special programs to improve the healthy behavior of this population is highly recommended.

High Turnover of Tissue Macrophages Contributes to Tuberculosis Reactivation in Simian Immunodeficiency Virus-Infected Rhesus Macaques

Background

Tuberculosis (TB) and human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) profoundly affect the immune system and synergistically accelerate disease progression. It is believed that CD4+ T-cell depletion by HIV is the major cause of immunodeficiency and reactivation of latent TB. Previous studies demonstrated that blood monocyte turnover concurrent with tissue macrophage death from virus infection better predicted AIDS onset than CD4+ T-cell depletion in macaques infected with simian immunodeficiency virus (SIV).

Methods

In this study, we describe the contribution of macrophages to the pathogenesis of Mycobacterium tuberculosis (Mtb)/SIV coinfection in a rhesus macaque model using in vivo BrdU labeling, immunostaining, flow cytometry, and confocal microscopy.

Results

We found that increased monocyte and macrophage turnover and levels of SIV-infected lung macrophages correlated with TB reactivation. All Mtb/SIV-coinfected monkeys exhibited declines in CD4+ T cells regardless of reactivation or latency outcomes, negating lower CD4+ T-cell levels as a primary cause of Mtb reactivation.

Conclusions

Results suggest that SIV-related damage to macrophages contributes to Mtb reactivation during coinfection. This also supports strategies to target lung macrophages for the treatment of TB.

Survival and predictors of mortality among children co-infected with tuberculosis and human immunodeficiency virus at University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia. A retrospective follow-up study

BACKGROUND

Tuberculosis (TB) is the leading cause of death in Human immunodeficiency virus (HIV) infected children globally. The aims of this study were to determine the mortality rate and to identify the predictors of mortality among TB/HIV co-infected children at University of Gondar Comprehensive Specialized Hospital.

METHOD

A retrospective follow-up study was conducted among TB/HIV co-infected children from February 2005 to March 2017. A Kaplan-Meier curve was used to estimate the median survival time. Bivariate and multivariable Cox proportional hazards models were fitted to identify the predictors of mortality.

RESULTS

A total of 271 TB/HIV co-infected children were included in the analysis. Of these, 38(14.02%) children were died during the follow-up period. This gives a total of 1167.67 child-years of observations. The overall mortality rate was 3.27(95%CI: 2.3-4.5) per 100 child-years. The independent predictors of time to death were age 1-5 years (as compared to age <1 year) (AHR = 0.3; 95%CI:0.09-0.98)), being anemic (AHR = 2.6; 95%CI:1.24-5.3), cotrimoxazole preventive therapy(CPT) non-users (AHR = 4.1; 95%CI:1.4-16.75), isoniazid preventive therapy(IPT) non-users (AHR = 2.95; 95%CI:1.16-7.5), having extra pulmonary tuberculosis(EPTB) (AHR = 2.43; 95%CI:1.1-5.3)) and fair or poor adherence to Anti-Retroviral Therapy (ART)(AHR = 3.5; 95%CI:1.7-7.5).

CONCLUSION

Mortality rate among TB/HIV co-infected children was high at University of Gondar Comprehensive Specialized Hospital. Age, extra-pulmonary tuberculosis, anemia, adherence, CPT and IPT were the independent predictors of mortality.