The prevalence and determinants of active tuberculosis among diabetes patients in Cape Town, South Africa, a high HIV/TB burden setting

Present outlooks on the prevalence of minimal and subclinical tuberculosis and current diagnostic tests: A systematic review and meta-analysis

BACKGROUND

Tuberculosis (TB) is a major global health issue, particularly in its minimal and subclinical forms, which often go undetected and contribute to transmission. Accurate prevalence assessment of these forms and the effectiveness of diagnostic tests are crucial for improving TB control, especially in high-risk populations such as those with HIV.

OBJECTIVES

This study aimed to determine the prevalence of minimal and subclinical TB and evaluate the positivity rates of current diagnostic tests.

METHODS

We conducted a meta-analysis of studies published from January 2000 to December 2022. Prevalence rates and diagnostic test results, including sputum culture, smear microscopy, TST/IGRA, and chest X-ray, were analyzed, with pooled prevalence calculated and comparisons made between geographic regions.

RESULTS

Minimal TB prevalence ranged from 0.9 % to 22.9 % in the general population, while subclinical TB prevalence was 0.05 % to 0.64 %, and 1.57 % to 14.63 % among individuals with HIV. The overall pooled prevalence of minimal TB was 7 % (95 % CI: 5-9 %), with higher rates in Asia (8 %, 95 % CI: 5-12 %) compared to Africa (6 %, 95 % CI: 4-8 %). Subclinical TB had a pooled prevalence of 0.2 % (95 % CI: 0.2-0.3 %) overall and 52 % (95 % CI: 46-58 %) among TB cases, with higher rates in Asia (60 %) compared to Africa (44 %). Diagnostic test positivity was 77 % (sputum culture), 15 % (smear microscopy), 64 % (TST/IGRA), and 53 % (chest X-ray).

CONCLUSIONS

This study reveals significant variability in the prevalence of minimal and subclinical TB. The findings highlight the need for improved diagnostic methods to reduce undetected cases, especially in high-risk populations.

Tackling syndemics by integrating infectious and noncommunicable diseases in health systems of low- and middle-income countries: A narrative systematic review

The co-occurrence of infectious diseases (ID) and non-communicable diseases (NCD) is widespread, presenting health service delivery challenges especially in low-and middle-income countries (LMICs). Integrated health care is a possible solution but may require a paradigm shift to be successfully implemented. This literature review identifies integrated care examples among selected ID and NCD dyads. We searched PubMed, PsycINFO, Cochrane Library, CINAHL, Web of Science, EMBASE, Global Health Database, and selected clinical trials registries. Eligible studies were published between 2010 and December 2022, available in English, and report health service delivery programs or policies for the selected disease dyads in LMICs. We identified 111 studies that met the inclusion criteria, including 56 on tuberculosis and diabetes integration, 46 on health system adaptations to treat COVID-19 and cardiometabolic diseases, and 9 on COVID-19, diabetes, and tuberculosis screening. Prior to the COVID-19 pandemic, most studies on diabetes-tuberculosis integration focused on clinical service delivery screening. By far the most reported health system outcomes across all studies related to health service delivery (n = 72), and 19 addressed health workforce. Outcomes related to health information systems (n = 5), leadership and governance (n = 3), health financing (n = 2), and essential medicines (n = 4)) were sparse. Telemedicine service delivery was the most common adaptation described in studies on COVID-19 and either cardiometabolic diseases or diabetes and tuberculosis. ID-NCD integration is being explored by health systems to deal with increasingly complex health needs, including comorbidities. High excess mortality from COVID-19 associated with NCD-related comorbidity prompted calls for more integrated ID-NCD surveillance and solutions. Evidence of clinical integration of health service delivery and workforce has grown-especially for HIV and NCDs-but other health system building blocks, particularly access to essential medicines, health financing, and leadership and governance, remain in disease silos.

Subclinical tuberculosis: a meta-analysis of prevalence and scoping review of definitions, prevalence and clinical characteristics

BACKGROUND

This scoping review aimed to characterise definitions used to describe subclinical tuberculosis (TB), estimate the prevalence in different populations and describe the clinical characteristics and treatment outcomes in the scientific literature.

METHODS

A systematic literature search was conducted using PubMed. We included studies published in English between January 1990 and August 2022 that defined "subclinical" or "asymptomatic" pulmonary TB disease, regardless of age, HIV status and comorbidities. We estimated the weighted pooled proportions of subclinical TB using a random-effects model by World Health Organization reported TB incidence, populations and settings. We also pooled the proportion of subclinical TB according to definitions described in published prevalence surveys.

RESULTS

We identified 29 prevalence surveys and 71 other studies. Prevalence survey data (2002-2022) using "absence of cough of any duration" criteria reported higher subclinical TB prevalence than those using the stricter "completely asymptomatic" threshold. Prevalence estimates overlap in studies using other symptoms and cough duration. Subclinical TB in studies was commonly defined as asymptomatic TB disease. Higher prevalence was reported in high TB burden areas, community settings and immunocompetent populations. People with subclinical TB showed less extensive radiographic abnormalities, higher treatment success rates and lower mortality, although studies were few.

CONCLUSION

A substantial proportion of TB is subclinical. However, prevalence estimates were highly heterogeneous between settings. Most published studies incompletely characterised the phenotype of people with subclinical TB. Standardised definitions and diagnostic criteria are needed to characterise this phenotype. Further research is required to enhance case finding, screening, diagnostics and treatment options for subclinical TB.

Prevalence and association of HIV and tuberculosis status in older adults in South Africa: an urgent need to escalate the scientific and political attention to aging and health

Objectives

This study examined the prevalence and sociodemographic factors among older adults with HIV and TB status in South Africa.

Methods

This data was cross-sectional and obtained from the 2019 General Household Surveys in South Africa. Adults 50 years and over with reported HIV and TB status were included (N = 9,180,047). We reported statistical analyses of the descriptive, Chi-square and Fisher's exact tests, and binary logistic regression.

Results

The study has found a prevalence rate of HIV to be 5.3% and TB to be 2.9% among older adults aged 50 years and above in South Africa. However, the study found HIV and TB to be highest among older adults residing in Gauteng, KwaZulu-Natal and Eastern Cape provinces. For HIV status, the female gender [AOR = 0.80*, CI 95% = 0.80-0.80] and secondary education [AOR = 0.57, CI 95% = 0.56-0.58] have lower odds of association among older adults with HIV. Regarding TB status, primary education [AOR = 1.08*, CI 95% = 1.06-1.10] and diabetes [AOR = 1.87*, CI 95% = 1.82-1.91] have lower likelihoods of associations among older adults with TB.

Conclusion

There is an urgent need to escalate scientific and political attention to address the HIV/TB burden in older adults and, public health policymakers need to take cognizance of the interdependence of inequality, mobility, and behavioural modification among this high-risk population.

Burden of active pulmonary tuberculosis among patients with diabetes in Dar es Salaam, Tanzania: a cross-sectional study

OBJECTIVES

We aimed to determine the prevalence, associated factors and describe the chest radiographic findings for active pulmonary tuberculosis (TB) among patients with diabetes mellitus (DM) attending a diabetic clinic in Tanzania.

DESIGN

Cross-sectional study.

SETTING

A diabetic clinic at Temeke Regional Referral Hospital in Dar es salaam, Tanzania.

PARTICIPANTS

Patients with diabetes.

MAIN OUTCOME MEASURES

The prevalence and factors associated with active TB in patients with DM.

RESULTS

Among 623 patients with DM screened, 11 (1.8%); 95% CI 0.9 to 3.1, had active TB of which 6 (54.5%) were GeneXpert positive and 5 (45.5%) were diagnosed based on clinical symptoms and suggestive chest radiographs. The risk of active TB was lower in patients aged 45-64 years compared with age below 45 years (adjusted prevalence ratio (aPR) 0.39, 95% CI (0.11 to 0.42), p=0.001) and in patients with normal chest examination findings compared with patients with crackles or bronchial breathing sounds (aPR 0.02, 95% CI (0.01 to 0.15), p<0.01). The predominant chest radiographic findings were opacification 100% mainly in the upper and mid-lung zones.

CONCLUSION

Diabetics should be screened for pulmonary TB, particularly among individuals aged 45 years and below with crackles or bronchial breathing on auscultation of the chest. High index of suspicion could help in the early detection and control of TB.

Functioning Problems Associated with Health Conditions with Greatest Disease Burden in South Africa: A Scoping Review

A notable rise in health-related disability for which evidence-based rehabilitation is beneficial is evident in low-to-middle income countries. This scoping review aimed to systematically identify and map the most common functioning problems associated with health conditions that contribute most to disability in South Africa using the International Classification of Functioning, Disability and Health (ICF) framework. Peer-reviewed evidence published from January 2006 to December 2021 was systematically searched from five databases. Some 268 studies reporting on functioning problems (impairments, activity limitations, and participation restrictions) in South African adults (>18 years) related to 10 health conditions were included. A total of 130 different functioning problems were mapped to the ICF. The most prevalent problems (top 20) were related to mobility, pain, and mental health but spanned across several ICF domains and were mostly in patients at primary care. The high prevalence and wide range of functioning problems may be particularly burdensome on an already strained primary health care (PHC) system. This points towards targeted planning of innovative strategies towards strengthening rehabilitation service delivery at primary care to address these complexities where there is an inadequate rehabilitation workforce.

Number needed to screen for TB in clinical, structural or occupational risk groups

BACKGROUND: Screening for active TB using active case-finding (ACF) may reduce TB incidence, prevalence, and mortality; however, yield of ACF interventions varies substantially across populations. We systematically reviewed studies reporting on ACF to calculate the number needed to screen (NNS) for groups at high risk for TB.METHODS: We conducted a literature search for studies reporting ACF for adults published between November 2010 and February 2020. We determined active TB prevalence detected through various screening strategies and calculated crude NNS for - TB confirmed using culture or Xpert^® MTB/RIF, and weighted mean NNS stratified by screening strategy, risk group, and country-level TB incidence.RESULTS: We screened 27,223 abstracts; 90 studies were included (41 in low/moderate and 49 in medium/high TB incidence settings). High-risk groups included inpatients, outpatients, people living with diabetes (PLWD), migrants, prison inmates, persons experiencing homelessness (PEH), healthcare workers, and miners. Screening strategies included symptom-based screening, chest X-ray and Xpert testing. NNS varied widely across and within incidence settings based on risk groups and screening methods. Screening tools with higher sensitivity (e.g., Xpert, CXR) were associated with lower NNS estimates.CONCLUSIONS: NNS for ACF strategies varies substantially between adult risk groups. Specific interventions should be tailored based on local epidemiology and costs.

Recurrent subclinical tuberculosis among ART accessing participants: Incidence, clinical course, and outcomes

BACKGROUND

Undiagnosed asymptomatic subclinical tuberculosis (TB) remains a significant threat to global TB control and accounts for a substantial proportion of cases among people living with HIV/AIDS (PLWHA). We determined the incidence, progression, and outcomes of subclinical TB in anti-retroviral therapy (ART) accessing PLWHA with known previous TB in South Africa.

METHODS

A total of 402 adult PLWHA previously treated for TB were enrolled in the prospective CAPRISA TRuTH (TB Recurrence Upon TB and HIV treatment) study. Participants were screened for TB with quarterly clinical and bacteriologic evaluation and bi-annual chest radiographs over 36 months. Those with suspected or confirmed TB were referred to the National TB Programme. Participants received HIV services, including ART. Incidence rate of TB was estimated by Poisson regression, and descriptive statistical analyses summarised data.

RESULTS

A total of 48/402 (11.9%) bacteriologically confirmed incident recurrent TB cases was identified, comprising 17/48 (35.4%) subclinical TB cases and 31/48 (64.5%) clinical TB cases. Age, sex, and body mass index (BMI) were similar among subclinical , clinical , and no TB groups. Incidence rates of recurrent TB overall; in clinical TB; and subclinical TB groups was 2.3 [95% CI: 1.7-3.0]; 1.5 [95% CI: 1.1-2.2]; and 0.9 [95% CI: 0.5-1.4] per 100 person-years, respectively. In the subclinical TB group, 14/17 (82.4%) was diagnosed by TB culture only, 11/17 (64.7%) received TB treatment, and 6/17 (35.3%) resolved TB spontaneously.

CONCLUSION

The high incidence rates of recurrent subclinical TB in PLWHA highlight inadequacies of symptom-based TB screening in high TB-HIV burden settings.

Treatment outcomes of Gene Xpert positive tuberculosis patients in KwaMashu Community Health Centre, KwaZulu-Natal, South Africa: A retrospective review

Background

We sought to investigate the relationship between tuberculosis (TB) treatment outcomes and its predictors in the KwaMashu region in KwaZulu-Natal (KZN). This area is currently a hotbed for TB and human immunodeficiency virus (HIV) co-infection.

Method

A retrospective study design was adopted to characterise adult patients diagnosed with Gene Expert (GXP) positive pulmonary TB from 01 January 2016 to 31 December 2017. Tuberculosis treatment outcomes were assessed after two months and five months according to the standard World Health Organization (WHO) criteria. Multiple logistic regression analysis was used to calculate the odds ratio (OR) of the possible determinants associated with unsuccessful treatment outcomes.

Results

Amongst the 596 patients diagnosed, 57.4% (95% confidence interval [CI]: 53.3–61.4; 342 of 596) had successful treatment outcomes. Of these reported cases, 88.89% (85.1–92.0; 304 of 342) were cured. For the unsuccessful treatment outcomes, 52.4% (46.0–58.6; 133 of 254) patients were lost to follow-up, 20.9% (16.0–26.4; 53 of 254) failed treatment, 1.2% (0.2–3.4; 3 of 254) died and 25.6% (20.3–31.4; 65 of 254) of the patients could not be accounted for. Patients with unknown HIV status were more likely to have unsuccessful treatment outcomes (adjusted OR [aOR] = 4.94 [1.83–13.36]). Patients who had sputum conversion at 2 months (aOR = 1.94 [1.27–2.96]) were significantly more likely to exhibit unsuccessful treatment outcomes.

Conclusion

Treatment success rate was 57.4% which was below the target set by the WHO. This underscores the urgent need to strengthen treatment adherence strategies to improve outcomes, especially in high HIV burden settings.

Screening diabetes mellitus patients for pulmonary tuberculosis: a multisite study in Indonesia, Peru, Romania and South Africa

BACKGROUND

Diabetes mellitus (DM) patients are three times more likely to develop tuberculosis (TB) than the general population. Active TB screening in people with DM is part of a bidirectional approach. The aim of this study was to conduct pragmatic active TB screening among DM patients in four countries to inform policy.

METHODS

DM patients were recruited in Indonesia (n=809), Peru (n=600), Romania (n=603) and South Africa (n=51). TB cases were diagnosed using an algorithm including clinical symptoms and chest X-ray. Presumptive TB patients were examined with sputum smear and culture.

RESULTS

A total of 171 (8.3%) individuals reported ever having had TB (South Africa, 26%; Indonesia, 12%; Peru, 7%; Romania, 4%), 15 of whom were already on TB treatment. Overall, 14 (0.73% [95% confidence interval 0.40 to 1.23]) TB cases were identified from screening. Poor glucose control, smoking, lower body mass index, education and socio-economic status were associated with newly diagnosed/current TB. Thirteen of the 14 TB cases diagnosed from this screening would have been found using a symptom-based approach.

CONCLUSIONS

These data support the World Health Organization recommendation for routine symptom-based screening for TB in known DM patients in high TB-burden countries. DM patients with any symptoms consistent with TB should be investigated and diagnostic tools should be easily accessible.

Behaviour is the Key in a Pandemic: The Direct and Indirect Effects of COVID-19-Related Variables on Psychological Wellbeing

The aim of this study was to investigate the potential role of three COVID-19-related variables (i.e., risk perception, knowledge, and behaviour) on four indices of pandemic-related mental health (i.e., anxiety, depression, loneliness, and hopelessness). In total, 337 participants completed four self-report questionnaires: selected subscales of the World Health Organisation's COVID-19 Behavioural Insights Tool, UCLA Loneliness Scale, State-Trait Anxiety Inventory-Trait Scale, Center for Epidemiologic Studies Depression Scale, and Beck Hopelessness Scale. In addition to descriptive statistics and intercorrelations, structural equation modelling was used to compare three models of the potential role (predictor or moderator/mediator) that the three abovementioned COVID-19-related variables could play in psychological wellbeing. The results showed high levels of psychological distress among the current sample. Generally, better knowledge of COVID-19 and engaging in protective behaviours were found to be related to lower levels of psychological distress, whereas increased risk perception was found to be associated with increased feelings of loneliness, anxiety, and depression. It was also found that behaviour mediated the effect of knowledge on psychological wellbeing, suggesting that while publicising information about COVID-19 remains necessary, providing the public with a means to engage in protective behaviours is central for promoting psychological wellbeing.

The association of glycemic level and prevalence of tuberculosis: a meta-analysis

BACKGROUND

Diabetes is a well-known risk factor for tuberculosis and poorly glycemic control may increase the risk of tuberculosis. We performed a meta-analysis to explore the association of glycemic control in diabetic patients and their tuberculosis prevalence.

METHODS

We included observational studies that investigated the prevalence of tuberculosis associated with glycemic control. The markers of glycated hemoglobin A1c (HbA1c) and fasting plasma glucose were used to evaluate the exposure of interest in the study. We searched related articles in PubMed, EMBASE and Web of Science through 14 December 2019. The Newcastle-Ottawa scale was used to assess the risk of bias of included studies.

RESULTS

Seventeen studies (four cohort studies, five case-control studies and eight cross-sectional studies) were included, involving 1,027,074 participants. The meta-analysis found the pooled odds ratio of prevalent tuberculosis increased a 2.05-fold (95%CI: 1.65, 2.55) for the patients with HbA1c ≥7.0% compared to those with HbA1c concentration < 7.0%. Furthermore, we found the mean of HbA1c was higher in the diabetes mellitus with tuberculosis group than the diabetes-only group (P = 0.002). In the sensitivity analysis, the finding remains consistent.

CONCLUSION

Our study provides the evidence that poorly controlled diabetes in diabetics may be associated with increased prevalence of tuberculosis. More efforts should focus on screening tuberculosis in uncontrolled diabetes.

Clinical Outcome of Single-Stage Decompression and Posterior Stabilization in Thoracolumbar Spinal Tuberculosis

Background Thoracolumbar spine constitutes the most common site for spinal tuberculosis. Though the treatment of spinal tuberculosis is antitubercular drugs initially, the patient with neurologic weakness warrants definitive surgical procedure of decompression and stabilization. Even though many investigators have reported favorable results with anterior decompression and stabilization surgery, due to the increased morbidity and complications, the posterior-only approach with decompression and stabilization has evolved as the operation of choice in recent time.

Methods All patients aged between 18 and 70 years with clinically and radiologically proven symptomatic thoracolumbar spinal tuberculosis who failed with conservative treatment for 4 weeks or developed neurologic weakness between the treatments are included in this study. All patients were offered decompression and posterior stabilization with transpedicular screws and rods after explaining the above procedure. Clinical outcome was measured by modified Frankel grading; AIS (American Spinal Injury Association impairment score) grade impairment score; and pain assessment done with visual analog scale (VAS) pre- and postoperatively and at 3, 6, and 9 months of interval.

Results The postoperative pain relief, neurologic improvement as per modified Frankel grade, AIS grade, and improvement in erythrocyte sedimentation rate and C-reactive protein were significant as compared with the preoperative status. The surgical interventions thus prove to have adequate relief to the patient and arresting the disease progression. The surgical outcome has very minimal intra- and postoperative complications.

Conclusion Single-stage decompression and posterior stabilization in thoracolumbar spinal tuberculosis is safe, effective, and results in good clinical outcome. The advantages of surgery include thorough debridement, decompression, and achievement of spinal stabilization.

Molecular detection of Mycobacterium tuberculosis in blood stained sputum samples using GeneXpert PCR assay

This study investigated the possibility of detecting Mycobacterium tuberculosis (MTB) in blood-stained sputa with GeneXpert assay (Xpert MTB/Rif G4 v.5) using appropriate blood lysing (distilled water and distilled water/carbon tetrachloride) and protein denaturing (guanidinium chloride and heat) agents. Blood free sputa were collected from individuals infected with MTB. Various levels of blood-spiked sputa (0%-50%) were prepared and subsequently assayed with GeneXpert analyzer. GeneXpert was found to be reproducible at less than 2% blood contamination. However, beyond 5% blood contamination, GeneXpert was unreliable with absolute PCR inhibition at 20% of blood contamination. Boiling at 95°C for 5 minutes was able to recover MTB DNA in previously undetectable levels as well as in 57% of patients' sputa with blood stains with previous negative GeneXpert results.

The Interaction of Diabetes and Tuberculosis: Translating Research to Policy and Practice

Diabetes Mellitus increases the risk of developing Tuberculosis (TB) disease by about three times; it also doubles the risk of death during TB treatment and other poor TB treatment outcomes. Diabetes may increase the risk of latent infection with Mycobacterium tuberculosis (LTBI), but the magnitude of this effect is less clear. Whilst this syndemic has received considerable attention, most of the published research has focussed on screening for undiagnosed diabetes in TB patients or observational follow-up of TB treatment outcomes by diabetes status. There are thus substantial research and policy gaps, particularly with regard to prevention of TB disease in people with diabetes and management of patients with TB-diabetes, both during TB treatment and after successful completion of TB treatment, when they likely remain at high risk of TB recurrence, mortality from TB and cardiovascular disease. Potential strategies to prevent development of TB disease might include targeted vaccination programmes, screening for LTBI and preventive therapy among diabetes patients or, perhaps ideally, improved diabetes management and prevention. The cost-effectiveness of each of these, and in particular how each strategy might compare with targeted TB prevention among other population groups at higher risk of developing TB disease, is also unknown. Despite research gaps, clinicians urgently need practical management advice and more research evidence on the choice and dose of different anti-diabetes medication and effective medical therapies to reduce cardiovascular risks (statins, anti-hypertensives and aspirin). Substantial health system strengthening and integration may be needed to prevent these at risk patients being lost to care at the end of TB treatment.

Prevalence of comorbidities and their associated factors in patients with type 2 diabetes at a tertiary care department in Ningbo, China: a cross-sectional study

OBJECTIVES

To determine the prevalence of comorbidities in patients with type 2 diabetes mellitus (T2DM) and identify the factors independently associated with comorbidities in a tertiary care department in Ningbo, China.

DESIGN

A computerised medical records database was used to conduct a cross-sectional study.

SETTING

The study was conducted in a tertiary care department in Ningbo, China.

PARTICIPANTS

The study was conducted on adult patients with T2DM, and it included 8 years of data, from 1 January 2012 to 31 December 2019.

THE PRIMARY OUTCOME MEASURE

Comorbidity was defined as the coexistence of at least one other chronic condition, that is, either a physical non-communicable disease (duration ≥3 months), a mental health condition (duration ≥3 months) or an infectious disease (duration ≥3 months).

RESULTS

In total, 4777 patients with T2DM satisfied the eligibility criteria. Over 8 years, the prevalence of comorbidities was 93.7%. The odds of comorbidities increased with the age of patients (18 to 39 years: 1; 40 to 59 years: OR 2.80, 95% CI 1.98 to 3.96; 60 to 69 years: OR 4.43, 95% CI 3.04 to 6.44; and ≥70 years: OR 10.97, 95% CI 7.17 to 16.77). The odds were lower in female patients (OR 0.66, 95% CI 0.51 to 0.84), patients residing in rural areas (OR 0.75, 95% CI 0.59 to 0.95) and patients without health insurance (OR 0.62, 95% CI 0.46 to 0.83). The odds were higher in single/divorced/widowed patients compared with those in married patients (OR 1.95, 95% CI 1.21 to 3.12).

CONCLUSIONS

A large percentage of patients with T2DM in the tertiary care department in Ningbo, China, had comorbidities, and the factors associated with comorbidities were identified. The findings could be used in developing, evaluating and implementing interventions aimed at improving outcomes in patients with T2DM with comorbidities.

Distinct epigenetic regulation in patients with multidrug-resistant TB-HIV co-infection and uninfected individuals

BACKGROUND

Mycobacterium tuberculosis (Mtb) is an airborne pathogenic microorganism that causes tuberculosis (TB). This pathogen invades lung tissues causing pulmonary infections and disseminates into other host organs. The Bacillus Calmette-Guérin (BCG) vaccine is employed to provide immune protection against TB; however, its efficacy is dependent on the age, immune status and geographic location of vaccinated individuals. Advanced diagnostic approaches such as GeneXpert MTB/RIF® and line probe assays (LPAs) have allowed rapid detection of drug-resistant, multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains. However, in sub-Saharan Africa, public and private health institutions are further burdened by the high prevalence of Human Immunodeficiency Virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS) and TB co-infections across different age groups. Epigenetic mechanisms have been widely exploited by Mtb and HIV to bypass the host's innate and adaptive immune responses, leading to microbial proliferation and disease manifestation. In the current study, we investigated the impact of epigenetic mechanisms in regulating target gene expression in healthy and patients co-infected with MDR TB-HIV.

Fixed dose drug combinations - are they pharmacoeconomically sound? Findings and implications especially for lower- and middle-income countries

Introduction: There are positive aspects regarding the prescribing of fixed dose combinations (FDCs) versus prescribing the medicines separately. However, these have to be balanced against concerns including increased costs and their irrationality in some cases. Consequently, there is a need to review their value among lower- and middle-income countries (LMICs) which have the greatest prevalence of both infectious and noninfectious diseases and issues of affordability.Areas covered: Review of potential advantages, disadvantages, cost-effectiveness, and availability of FDCs in high priority disease areas in LMICs and possible initiatives to enhance the prescribing of valued FDCs and limit their use where there are concerns with their value.Expert commentary: FDCs are valued across LMICs. Advantages include potentially improved response rates, reduced adverse reactions, increased adherence rates, and reduced costs. Concerns include increased chances of drug:drug interactions, reduced effectiveness, potential for imprecise diagnoses and higher unjustified prices. Overall certain FDCs including those for malaria, tuberculosis, and hypertension are valued and listed in the country's essential medicine lists, with initiatives needed to enhance their prescribing where currently low prescribing rates. Proposed initiatives include robust clinical and economic data to address the current paucity of pharmacoeconomic data. Irrational FDCs persists in some countries which are being addressed.

IL-22 produced by type 3 innate lymphoid cells (ILC3s) reduces the mortality of type 2 diabetes mellitus (T2DM) mice infected with Mycobacterium tuberculosis

Previously, we found that pathological immune responses enhance the mortality rate of Mycobacterium tuberculosis (Mtb)-infected mice with type 2 diabetes mellitus (T2DM). In the current study, we evaluated the role of the cytokine IL-22 (known to play a protective role in bacterial infections) and type 3 innate lymphoid cells (ILC3s) in regulating inflammation and mortality in Mtb-infected T2DM mice. IL-22 levels were significantly lower in Mtb-infected T2DM mice than in nondiabetic Mtb-infected mice. Similarly, serum IL-22 levels were significantly lower in tuberculosis (TB) patients with T2DM than in TB patients without T2DM. ILC3s were an important source of IL-22 in mice infected with Mtb, and recombinant IL-22 treatment or adoptive transfer of ILC3s prolonged the survival of Mtb-infected T2DM mice. Recombinant IL-22 treatment reduced serum insulin levels and improved lipid metabolism. Recombinant IL-22 treatment or ILC3 transfer prevented neutrophil accumulation near alveoli, inhibited neutrophil elastase 2 (ELA2) production and prevented epithelial cell damage, identifying a novel mechanism for IL-22 and ILC3-mediated inhibition of inflammation in T2DM mice infected with an intracellular pathogen. Our findings suggest that the IL-22 pathway may be a novel target for therapeutic intervention in T2DM patients with active TB disease.

Metformin as a host-directed therapeutic in tuberculosis: Is there a promise?

To complement the development of new or repurposed drugs for improving the treatment outcomes of drug-susceptible and drug-resistant tuberculosis, current insight also focuses on the use of host-directed therapy. Metformin, a drug often used in the management of type 2 diabetes mellitus, has attracted attention by virtue of its favourable activity as an adjunctive agent against tuberculosis, discovered through laboratory and clinical studies. To definitively establish its role as a host-directed therapeutic in tuberculosis, more preclinical and clinical research is still required to better delineate its mechanism(s) of action and optimal clinical use.

Post-primary pulmonary TB haemoptysis - When there is more than meets the eye

Haemoptysis is concerning for both patient and healthcare provider and points to the presence of severe underlying lung disease warranting investigation. Approximately 8% of patients with pulmonary tuberculosis (PTB) infection will experience haemoptysis at some point during their life ^[1;2]. The aetiology of haemoptysis in the setting of PTB is diverse and may occur during active or following prior PTB infection due to pulmonary complications. We describe the case of a 33-year-old female who presented with massive haemoptysis on two separate occasions within a five-month period. Her background history included PTB 6 years prior and subsequent post-TB bronchiectasis with a destroyed left lung, and the development of apical mycetoma's. Despite numerous pre-existing aetiologies that could account for haemoptysis in this patient, on this admission, a newly identified ruptured Rasmussen's aneurysm was identified by angiography and successfully treated with arterial embolization. This report serves to highlight the multitude of reasons for haemoptysis in a patient with post PTB lung destruction and the associated diagnostic challenges that may be present. In particular, we highlight the Rasmussen's aneurysm, a rare entity, as a hidden cause of haemoptysis, where despite extensive parenchymal lung disease identified on chest radiography, specialised imaging is needed to confirm the diagnosis.