Lower expression of Th1-related cytokines and inducible nitric oxide synthase in mice with streptozotocin-induced diabetes mellitus infected with Mycobacterium tuberculosis

Pulmonary tuberculosis and diabetes mellitus: Epidemiology, pathogenesis and therapeutic management (Review)

The dual burden of pulmonary tuberculosis (PTB) and diabetes mellitus (DM) is a major global public health concern. There is increasing evidence to indicate an association between PTB and DM. DM is associated with immune dysfunction and altered immune components. Hyperglycemia weakens the innate immune response by affecting the function of macrophages, dendritic cells, neutrophils, and natural killer cells, and also disrupts the adaptive immune response, thus promoting the susceptibility of PTB in patients with DM. Antituberculosis drugs often cause the impairment of liver and kidney function in patients with PTB, and the infection with Mycobacterium tuberculosis weaken pancreatic endocrine function by causing islet cell amyloidosis, which disrupts glucose metabolism and thus increases the risk of developing DM in patients with PTB. The present review discusses the association between PTB and DM from the perspective of epidemiology, pathogenesis, and treatment management. The present review aims to provide information for the rational formulation of treatment strategies for patients with PTB-DM.

Association between diabetes mellitus and cause of death in patients with tuberculosis: A Korean nationwide cohort study

Despite its significant impact on mortality, tuberculosis (TB)-diabetes mellitus (DM) co-prevalence has not been well-elucidated for the cause of death. We investigated the impact of DM on TB-related and non-TB-related deaths in patients with TB. This retrospective nationwide cohort study included patients diagnosed with TB between 2011 and 2017 in South Korea. We performed Fine and Gray regression model analyses to assess the mortality risk of DM classified by cause of death. Of 239,848 patients, 62,435 (26.0%) had DM, and 20,203 died during anti-TB treatment. Of all deaths, 47.9% (9,668) were caused by TB, and the remaining 52.1% (10,535) was attributed to various non-TB-related causes. The mortality rate was higher in the DM than in the non-DM groups in both men and women. DM was associated with a higher risk of TB-related (adjusted hazard ratio [aHR] 1.07, 95% confidence interval [CI] 1.01-1.13) and non-TB-related (aHR 1.21, 95% CI 1.15-1.27) deaths in men; however, only a higher risk of non-TB-related deaths (aHR 1.29, 95% CI 1.20-1.38) in women. Our findings indicate that DM is independently associated with a greater risk of death during anti-TB treatment among patients with TB for both TB-related and non-TB-related deaths.

The cause-effect relation of tuberculosis on incidence of diabetes mellitus

Tuberculosis (TB) is one of the oldest human diseases and is one of the major causes of mortality and morbidity across the Globe. Mycobacterium tuberculosis (Mtb), the causal agent of TB is one of the most successful pathogens known to mankind. Malnutrition, smoking, co-infection with other pathogens like human immunodeficiency virus (HIV), or conditions like diabetes further aggravate the tuberculosis pathogenesis. The association between type 2 diabetes mellitus (DM) and tuberculosis is well known and the immune-metabolic changes during diabetes are known to cause increased susceptibility to tuberculosis. Many epidemiological studies suggest the occurrence of hyperglycemia during active TB leading to impaired glucose tolerance and insulin resistance. However, the mechanisms underlying these effects is not well understood. In this review, we have described possible causal factors like inflammation, host metabolic changes triggered by tuberculosis that could contribute to the development of insulin resistance and type 2 diabetes. We have also discussed therapeutic management of type 2 diabetes during TB, which may help in designing future strategies to cope with TB-DM cases.

Advancing personalized medicine for tuberculosis through the application of immune profiling

While early and precise diagnosis is the key to eliminating tuberculosis (TB), conventional methods using culture conversion or sputum smear microscopy have failed to meet demand. This is especially true in high-epidemic developing countries and during pandemic-associated social restrictions. Suboptimal biomarkers have restricted the improvement of TB management and eradication strategies. Therefore, the research and development of new affordable and accessible methods are required. Following the emergence of many high-throughput quantification TB studies, immunomics has the advantages of directly targeting responsive immune molecules and significantly simplifying workloads. In particular, immune profiling has been demonstrated to be a versatile tool that potentially unlocks many options for application in TB management. Herein, we review the current approaches for TB control with regard to the potentials and limitations of immunomics. Multiple directions are also proposed to hopefully unleash immunomics' potential in TB research, not least in revealing representative immune biomarkers to correctly diagnose TB. The immune profiles of patients can be valuable covariates for model-informed precision dosing-based treatment monitoring, prediction of outcome, and the optimal dose prediction of anti-TB drugs.

The role of pathogens in diabetes pathogenesis and the potential of immunoproteomics as a diagnostic and prognostic tool

Diabetes mellitus (DM) is a group of metabolic diseases marked by hyperglycemia, which increases the risk of systemic infections. DM patients are at greater risk of hospitalization and mortality from bacterial, viral, and fungal infections. Poor glycemic control can result in skin, blood, bone, urinary, gastrointestinal, and respiratory tract infections and recurrent infections. Therefore, the evidence that infections play a critical role in DM progression and the hazard ratio for a person with DM dying from any infection is higher. Early diagnosis and better glycemic control can help prevent infections and improve treatment outcomes. Perhaps, half (49.7%) of the people living with DM are undiagnosed, resulting in a higher frequency of infections induced by the hyperglycemic milieu that favors immune dysfunction. Novel diagnostic and therapeutic markers for glycemic control and infection prevention are desirable. High-throughput blood-based immunoassays that screen infections and hyperglycemia are required to guide timely interventions and efficiently monitor treatment responses. The present review aims to collect information on the most common infections associated with DM, their origin, pathogenesis, and the potential of immunoproteomics assays in the early diagnosis of the infections. While infections are common in DM, their role in glycemic control and disease pathogenesis is poorly described. Nevertheless, more research is required to identify novel diagnostic and prognostic markers to understand DM pathogenesis and management of infections. Precise monitoring of diabetic infections by immunoproteomics may provide novel insights into disease pathogenesis and healthy prognosis.

Prevalence of Pulmonary Tuberculosis in Diabetic Patients: Epidemiology, Immunological Basis, and Its Amalgamated Management

Tuberculosis (TB) is one of the most widespread and infectious diseases in the world, which is brought on by Mycobacterium tuberculosis (MTB). Most infection lacks traditional signs. Latent TB is the name given to this ailment. Of these latent infections, 10% become active and cause illness. Fever, night sweats, a prolonged cough with blood-containing mucus, and weight loss are common signs of active TB infection. Diabetes, on the other hand, is a group of metabolic illnesses characterized by elevated serum glucose levels. It is a chronic metabolic condition brought on by a deficiency in insulin secretion or resistance. It is of two types, that is, type 1 and type 2. Among all the cases of diabetes, the occurrence of type 2 is more common and less fatal than type 1. The prevalence of diabetes is currently increasing in low- and middle-income nations. As both diabetes and TB come under the most widespread chronic condition; therefore, their combined effect is evaluated. In recent years, the higher occurrence of TB in patients with hyperglycemia has come to light. People with elevated blood glucose levels exhibit several risk factors that make them more vulnerable to contracting TB. This review provides information on epidemiological data about the prevalence of TB in patients with hyperglycemia. In addition, this paper discusses the immunological underpinnings of TB development in patients with diabetes mellitus and how glycemic management reduces the risk of TB infection. It illustrates how the clinical signs and radiographic evidence of TB differ between people with diabetes and healthy people and mentions diabetes and TB combined management.

A blunted GPR183/oxysterol axis during dysglycemia results in delayed recruitment of macrophages to the lung during M. tuberculosis infection

Background

We previously reported that reduced GPR183 expression in blood from tuberculosis (TB) patients with diabetes is associated with more severe TB.

Methods

To further elucidate the role of GPR183 and its oxysterol ligands in the lung, we studied dysglycemic mice infected with Mycobacterium tuberculosis (Mtb).

Results

We found upregulation of the oxysterol-producing enzymes CH25H and CYP7B1 and increased concentrations of 25-hydroxycholesterol upon Mtb infection in the lungs of mice. This was associated with increased expression of GPR183 indicative of oxysterol-mediated recruitment of GPR183-expressing immune cells to the lung. CYP7B1 was predominantly expressed by macrophages in TB granulomas. CYP7B1 expression was significantly blunted in lungs from dysglycemic animals, which coincided with delayed macrophage infiltration. GPR183-deficient mice similarly had reduced macrophage recruitment during early infection.

Conclusions

Taken together, we demonstrate a requirement of the GPR183/oxysterol axis for positioning of macrophages to the site of infection and add an explanation to more severe TB in diabetes patients.

Body Mass Index, Diabetes, and Risk of Tuberculosis: A Retrospective Cohort Study

Although both diabetes mellitus (DM) and underweight are associated with increased risk of tuberculosis (TB), there are limited data evaluating TB risk while considering two factors simultaneously—body mass index (BMI) and DM. A retrospective cohort study was performed with 10,087,903 participants of the Korean National Health Screening Program in 2009. The cohort was followed up to the date of TB incidence, death, or until December 31, 2018. We compared the incidence and risk of TB according to BMI category and DM. During the 7.3-year follow-up duration, the incidence of TB was 0.92 per 1,000 person-years in the normal weight without DM, 2.26 in the normal weight with DM, 1.80 in the underweight without DM, and 5.35 in the underweight with DM. Compared to the normal weight without DM, the normal weight with DM, the underweight without DM, and the underweight with DM showed a 1.51-fold (95% CI, 1.46–1.57), a 2.21-fold (95% CI, 2.14–2.28), and a 3.24-fold (95% CI, 2.95–3.56) increased risk of TB, respectively. However, compared to the normal weight without DM, the severely obese without DM and those with DM showed a 0.37 (95% CI, 0.36–0.38) and a 0.42 (95% CI, 0.36–0.48)-fold decreased risk of TB, respectively. There was no significant joint effect of BMI and DM on the risk of incident TB in the overall population; a synergistic effect of underweight and DM was evident in participants <65 years of age, current smokers, and heavy drinkers. In conclusion, being underweight or DM individually increases the risk of incident TB. Based on our study results, a focused screening of incident TB in patients with DM may be beneficial.

Host Immune-Metabolic Adaptations Upon Mycobacterial Infections and Associated Co-Morbidities

Mycobacterial diseases are a major public health challenge. Their causative agents include, in order of impact, members of the Mycobacterium tuberculosis complex (causing tuberculosis), Mycobacterium leprae (causing leprosy), and non-tuberculous mycobacterial pathogens including Mycobacterium ulcerans. Macrophages are mycobacterial targets and they play an essential role in the host immune response to mycobacteria. This review aims to provide a comprehensive understanding of the immune-metabolic adaptations of the macrophage to mycobacterial infections. This metabolic rewiring involves changes in glycolysis and oxidative metabolism, as well as in the use of fatty acids and that of metals such as iron, zinc and copper. The macrophage metabolic adaptations result in changes in intracellular metabolites, which can post-translationally modify proteins including histones, with potential for shaping the epigenetic landscape. This review will also cover how critical tuberculosis co-morbidities such as smoking, diabetes and HIV infection shape host metabolic responses and impact disease outcome. Finally, we will explore how the immune-metabolic knowledge gained in the last decades can be harnessed towards the design of novel diagnostic and therapeutic tools, as well as vaccines.

Pre-Diabetes Increases Tuberculosis Disease Severity, While High Body Fat Without Impaired Glucose Tolerance Is Protective

Type 2 diabetes (T2D) is a well-known risk factor for tuberculosis (TB), but little is known about pre-diabetes and the relative contribution of impaired glucose tolerance vs. obesity towards susceptibility to TB. Here, we developed a preclinical model of pre-diabetes and TB. Mice fed a high fat diet (HFD) for 12 weeks presented with impaired glucose tolerance and hyperinsulinemia compared to mice fed normal chow diet (NCD). Infection with M. tuberculosis (Mtb) H₃₇R_v after the onset of dysglycemia was associated with significantly increased lung pathology, lower concentrations of TNF-α, IFN-γ, IFN-β and IL-10 and a trend towards higher bacterial burden at 3 weeks post infection. To determine whether the increased susceptibility of pre-diabetic mice to TB is reversible and is associated with dysglycemia or increased body fat mass, we performed a diet reversal experiment. Pre-diabetic mice were fed a NCD for 10 additional weeks (HFD/NCD) at which point glucose tolerance was restored, but body fat mass remained higher compared to control mice that consumed NCD throughout the entire experiment (NCD/NCD). Upon Mtb infection HFD/NCD mice had significantly lower bacterial burden compared to NCD/NCD mice and this was accompanied by restored IFN-γ responses. Our findings demonstrate that pre-diabetes increases susceptibility to TB, but a high body mass index without dysglycemia is protective. This murine model offers the opportunity to further study the underlying immunological, metabolic and endocrine mechanisms of this association.

Active screening of patients with diabetes mellitus for pulmonary tuberculosis in a tertiary care hospital in Sri Lanka

End TB strategy by the WHO suggest active screening of high-risk populations for tuberculosis (TB) to improve case detection. Present study generates evidence for the effectiveness of screening patients with diabetes mellitus (DM) for Pulmonary TB (PTB). A study was conducted among 4548 systematically recruited patients over 45 years attending DM clinic at the National Hospital of Sri Lanka. The study units followed an algorithm specifying TB symptom and risk factor screening for all, followed by investigations and clinical assessments for those indicated. Bacteriologically confirmed or clinically diagnosed PTB were presented as proportions with 95% CI. Mean (SD) age was 62·5 (29·1) years. Among patients who completed all indicated steps of algorithm, 3500 (76·9%) were investigated and 127 (2·8%) underwent clinical assessment. Proportion of bacteriologically confirmed PTB patients was 0·1% (n = 6,95%CI = 0·0-0·3%). None were detected clinically. Analysis revealed PTB detection rates among males aged ≥60 years with HbA1c ≥ 8 to be 0·4% (n = 2, 95%CI = 0·0-1·4%). The study concludes that active screening for PTB among all DM patients at clinic settings in Sri Lanka, to be non-effective measure to enhance TB case finding. However, the sub-category of diabetic males with uncontrolled diabetics who are over 60 years of age is recommended as an option to consider for active screening for PTB.

Approaches to treating tuberculosis by encapsulating metal ions and anti-mycobacterial drugs utilizing nano- and microparticle technologies

Tuberculosis (TB) is caused by a bacterial infection that affects a number of human organs, primarily the lungs, but also the liver, spleen, and spine, causing key symptoms of fever, fatigue, and persistent cough, and if not treated properly, can be fatal. Every year, 10 million individuals become ill with active TB resulting with a mortality approximating 1.5 million. Current treatment guidelines recommend oral administration of a combination of first-line anti-TB drugs for at least 6 months. While efficacious under optimum conditions, 'Directly Observed Therapy Short-course' (DOTS) is not without problems. The long treatment time and poor pharmacokinetics, alongside drug side effects lead to poor patient compliance and has accelerated the emergence of multi-drug resistant (MDR) organisms. All this, combined with the limited number of newly discovered TB drugs to treat MDR-TB and shorten standard therapy time, has highlighted the need for new targeted drug delivery systems. In this respect, there has been recent focus on micro- and nano-particle technologies to prepare organic or/and metal particles loaded with TB drugs to enhance their efficacy by targeted delivery via the inhaled route. In this review, we provide a brief overview of the current epidemiology of TB, and risk factors for progression of latent stage tuberculosis (LTBI) to the active TB. We identify current TB treatment regimens, newly discovered TB drugs, and identify studies that have used micro- or nano-particles technologies to design a reliable inhalation drug delivery system to treat TB more effectively.

Slow radiological improvement and persistent low-grade inflammation after chemotherapy in tuberculosis patients with type 2 diabetes

Background

Diabetes mellitus type 2 (DM) may impede immune responses in tuberculosis (TB) and thus contribute to enhanced disease severity. In this study, we aimed to evaluate DM-mediated alterations in clinical, radiological and immunological outcomes in TB disease.

Methods

Newly diagnosed pulmonary TB patients with or without DM (TB n = 40; TB-DM n = 40) were recruited in Dhaka, Bangladesh. Clinical symptoms, sputum smear and culture conversion as well as chest radiography were assessed. Peripheral blood and sputum samples were collected at the time of diagnosis (baseline) and after 1, 2 and 6 months of standard anti-TB treatment. Blood samples were also obtained from healthy controls (n = 20). mRNA expression of inflammatory markers in blood and sputum samples were quantified using real-time PCR.

Results

The majority of TB-DM patients had poor glycemic control (HbA1c > 8%) and displayed elevated pulmonary pathology (P = 0.039) particularly in the middle (P < 0.004) and lower lung zones (P < 0.02) throughout the treatment period. However, reduction of clinical symptoms and time to sputum smear and culture conversion did not differ between the groups. Transcripts levels of the pro-inflammatory cytokines IL-1β (P = 0.003 at month-1 and P = 0.045 at month-2) and TNF-α (P = 0.005 at month-1) and the anti-inflammatory cytokine IL-10 (P = 0.005 at month-2) were higher in peripheral blood after anti-TB treatment in TB-DM compared to TB patients. Conversely in sputum, TB-DM patients had reduced CD4 (P < 0.009 at month-1) and IL-10 (P = 0.005 at month-1 and P = 0.006 at month-2) transcripts, whereas CD8 was elevated (P = 0.016 at month-2). At 1- and 2-month post-treatment, sputum IL-10 transcripts were inversely correlated with fasting blood glucose and HbA1c levels in all patients.

Conclusion

Insufficient up-regulation of IL-10 in the lung may fuel persistent local inflammation thereby promoting lung pathology in TB-DM patients with poorly controlled DM.

Diabetes in tuberculosis patients: An emerging public health concern and the determinants and impact on treatment outcome

BACKGROUND

Tuberculosis (TB) and diabetes mellitus are still of much public health concern. Screening of TB patients for diabetes will ensure early case detection, better management of diabetes, and better TB treatment outcome. The objective of this study was to determine the prevalence and associated factors of diabetes in TB patients and their impact on treatment outcome of TB.

MATERIALS AND METHODS

This was a longitudinal follow-up study of registered TB patients under the Revised National Tuberculosis Control Program in all five TB units of Bhopal district. Participants were contacted and the interview was conducted. The blood sugar of all TB patients was checked, and they were followed up to assess the treatment outcome from October 2014 to September 2017. Data were analyzed using SPSS (version 16.0. Chicago, SPSS Inc.). Logistic regression was done to find the factors for diabetes in TB patients. The Chi-square tests were used to find the difference in treatment outcomes and assess the relative risk for poor outcome in diabetic TB patients.

RESULTS

Of total 662 TB patients, 82 (12.39%) were diagnosed as diabetic. Age >50 years, males, higher body mass index, pulmonary TB, patients on Category II treatment, and history of smoking were found to be predictors of diabetes in TB patients. The treatment outcome of TB was more unfavorable (defaulter, failure, and death) in diabetic TB patients (16.17%) than in nondiabetic TB patients (5.8%) (risk ratio = 2.78, 1.469-5.284 confidence interval).

CONCLUSION

The high prevalence of diabetes and the unfavorable treatment outcome in diabetic TB patients make screening and management of diabetes at an early-stage crucial for a better outcome in TB patients.

Elevated antigen-specific IFN-γ responses in bronchoalveolar lavage fluid impervious to clinical comorbidities improve the pulmonary tuberculosis diagnosis

The extremely slow growth rate of Mycobacterium tuberculosis (Mtb) challenges traditional methods for tuberculosis (TB) diagnosis. Here, we assessed the efficacy of a previously developed Mtb antigen-specific gamma interferon (IFN-γ) enzyme-linked immunospot (ELISPOT) performed on bronchoalveolar lavage fluid (BALF) from a cohort of 414 patients including 333 PTB patients (202/333 were sputum culture positive) for the diagnosis of PTB. We could confirm that antigen-specific IFN-γ-producing CD4⁺ T cells were concentrated significantly in BALF mononuclear cells (BALMC) compared with that in peripheral blood mononuclear cells (PBMC) assayed in parallel, but not those of CD8⁺ T cells both in sputum culture-negative and positive PTB. The magnitude of IFN-γ responses in the BALF was associated with bacterial load, and 9/202 of PTB with endobronchial TB (EBTB) were slightly reduced by the anti-TB treatment. Moreover, antigen-specific IFN-γ ELISPOT performed on BALMC showed higher sensitivity than PBMC ELISPOT. In addition, the differences of the BALMC ELISPOT between PTB and PTB with diabetes were not found, whereas PBMC IFN-γ responses were decreased in PTB with diabetes. Combined with the microbiological detection in BALF, such as microscopy and culture, the BALMC ELISPOT offers the opportunity for the more accurate diagnosis of PTB, especially those with clinical comorbidities.

Increased susceptibility to Mycobacterium tuberculosis infection in a diet-induced murine model of type 2 diabetes

Tuberculosis (TB)-type 2 diabetes mellitus (T2D) comorbidity is re-emerging as a global public health problem. T2D is a major risk factor for increased susceptibility to TB infection and reactivation leading to higher morbidity and mortality. The pathophysiological mechanisms of T2D contributing to TB susceptibility are not fully understood, but likely involve dysregulated immune responses. In this study, a diet-induced murine model that reflects the cardinal features of human T2D was used to assess the immune responses following an intravenous Mycobacterium tuberculosis (Mtb) infection. In this study, T2D significantly increased mortality, organ bacillary burden and inflammatory lesions compared to non-diabetic controls. Organ-specific pro-inflammatory cytokine responses were dysregulated as early as one day post-infection in T2D mice. Macrophages derived from T2D mice showed reduced bacterial internalization and killing capacity. An early impairment of antimycobacterial functions of macrophages in diabetes is a key mechanism that leads to increased susceptibility of T2D.

Immunological Impacts of Diabetes on the Susceptibility of Mycobacterium tuberculosis

The interaction between diabetes and major world infections like TB is a major public health concern because of rapidly rising levels of diabetes. The dual burden of tuberculosis (TB) and diabetes mellitus (DM) has become a major global public health problem. Diabetes mellitus is a major risk factor for the development of active and latent tuberculosis. Immune mechanisms contributing to the increased susceptibility of diabetic patients to TB are due to the defects in bacterial recognition, phagocytic activity, and cellular activation which results in impaired production of chemokines and cytokines. The initiation of adaptive immunity is delayed by impaired antigen-presenting cell (APC) recruitment and function in hyperglycemic host, which results in reduced frequencies of Th1, Th2, and Th17 cells and its secretion of cytokines having a great role in activation of macrophage and inflammatory response of tuberculosis. In addition, impaired immune response and killing of intracellular bacteria potentially increase bacterial load, chronic inflammation, and central necrosis that facilitate bacterial dissemination and miliary tuberculosis. Understanding of the immunological and biochemical basis of TB susceptibility in diabetic patients will tell us the rational development of implementation and therapeutic strategies to alleviate the dual burden of the diseases. Therefore, the aim of this review was focused on the association between diabetes and tuberculosis, focusing on epidemiology, pathogenesis, and immune dysfunction in diabetes mellitus, and its association with susceptibility, severity, and treatment outcome failure to tuberculosis.

Dysregulation of key cytokines may contribute to increased susceptibility of diabetic mice to Mycobacterium bovis BCG infection

Diabetes is one of the major co-morbidities contributing to the high global burden of tuberculosis (TB). The increased susceptibility of individuals with type 2 diabetes (T2D) to TB is multifactorial and may influence the efficacy of vaccines. This study was undertaken to determine the early immune responses that occur following infection with Mycobacterium bovis Bacille Calmette-Guérin (BCG) in a diet-induced murine model of T2D. The phagocytic capabilities of alveolar (AM) and resident peritoneal macrophages (RPM) were assessed using ex vivo assays. Compared to macrophages from non-diabetic mice, macrophages from diabetic animals showed decreased BCG uptake and killing and inflammatory cytokine production (TNF-α, MCP-1, IL-6, IL-1β). In vivo susceptibility to BCG was determined following intravenous infection and diabetic mice showed a trend towards increased mortality, higher bacterial burden in the lung, liver and spleen and increased inflammatory lesions compared to controls. Differences between tissue cytokines were observed as early as one day post-infection and by days 14 and 35, lung and liver TNF-α and IFN-γ levels were decreased in diabetic mice compared to controls. These results suggest that early dysregulated immune responses may influence the susceptibility of T2D mice to BCG infection.

Effect of Diabetes Mellitus on the Pharmacokinetics and Pharmacodynamics of Tuberculosis Treatment

Diabetes mellitus (DM) and tuberculosis (TB) are two common diseases with increasing geographic overlap and clinical interactions. The effect of DM and hemoglobin A1c (HbA1c) values on the pharmacokinetics (PK) and pharmacodynamics (PD) of anti-TB drugs remains poorly characterized. Newly diagnosed TB patients with and without DM starting fixed-dose, thrice-weekly treatment underwent sampling for PK assessments (predose and 0.5, 2, and 6 h postdose) during the intensive and continuation phases of treatment. The effect of DM and HbA1c values on the maximum concentration (C _max) of rifampin, isoniazid, and pyrazinamide and the association between drug concentrations and microbiologic and clinical outcomes were assessed. Of 243 patients, 101 had DM. Univariate analysis showed significant reductions in the C _max of pyrazinamide and isoniazid (but not rifampin) with DM or increasing HbA1c values. After adjusting for age, sex, and weight, DM was associated only with reduced pyrazinamide concentrations (adjusted geometric mean ratio = 0.74, P = 0.03). In adjusted Cox models, female gender (adjusted hazards ratio [aHR] = 1.75, P = 0.001), a lower smear grade with the Xpert assay (aHR = 1.40, P < 0.001), and the pyrazinamide C _max (aHR = 0.99, P = 0.006) were independent predictors of sputum culture conversion to negative. Higher isoniazid or rifampin concentrations were associated with a faster time to culture conversion in patients with DM only. A pyrazinamide C _max above the therapeutic target was associated with higher unfavorable outcomes (treatment failure, relapse, death) (odds ratio = 1.92, P = 0.04). DM and higher HbA1c values increased the risk of not achieving therapeutic targets for pyrazinamide (but not rifampin or isoniazid). Higher pyrazinamide concentrations, though, were associated with worse microbiologic and clinical outcomes. DM status also appeared to influence PK-PD relationships for isoniazid and rifampin.

Friends and foes of tuberculosis: modulation of protective immunity

Protective immunity in tuberculosis (TB) is subject of debate in the TB research community, as this is key to fully understand TB pathogenesis and to develop new promising tools for TB diagnosis and prognosis as well as a more efficient TB vaccine. IFN-γ producing CD4+ T cells are key in TB control, but may not be sufficient to provide protection. Additional subsets have been identified that contribute to protection such as multifunctional and cytolytic T-cell subsets, including classical and nonclassical T cells as well as novel innate immune cell subsets resulting from trained immunity. However, to define protective immune responses against TB, the complexity of balancing TB immunity also has to be considered. In this review, insights into effector cell immunity and how this is modulated by regulatory cells, associated comorbidities and the host microbiome, is discussed. We systematically map how different suppressive immune cell subsets may affect effector cell responses at the local site of infection. We also dissect how common comorbidities such as HIV, helminths and diabetes may bias protective TB immunity towards pathogenic and regulatory responses. Finally, also the composition and diversity of the microbiome in the lung and gut could affect host TB immunity. Understanding these various aspects of the immunological balance in the human host is fundamental to prevent TB infection and disease.

Comparison of acid fast bacilli (AFB) smear for Mycobacterium tuberculosis on adult pulmonary tuberculosis (TB) patients with type 2 diabetes mellitus (DM) and without type 2 DM

Background

According to the Global Tuberculosis Report 2015, Indonesia ranked as second country in the world with the highest number of pulmonary tuberculosis cases. By 2015, the number of pulmonary TB new cases in Indonesia has increased to 330.910 cases of 2014 where 324.539 cases. DM is one of the most important factors that influence the occurrence worsening TB. Now is known that DM patients have body's immune response disorder thereby facilitating M. tuberculosis infection and causing TB.

Method

This research is cross sectional design. The sample in this research are adult pulmonary TB patients at General Hospital Grade C period October 1, 2013–March 31, 2016 as much as 225 patients.

Result

AFB smear results in patients with type 2 DM with smear 3 + was 14 (17.28%), 2 + was 15 (18.52%), 1 + was 15 (18.52%) and negative (−) was 37 (45.68%). AFB smear results in patients without type 2 DM with smear 3 + was 3 (2.08%), 2 + was 6 (4.17%), 1 + was 19 (13.19%), negative (−) was 112 (77.78%) and have no sputum was 4 (2.78%). Number of adult pulmonary TB patients were 225 patients. Of the 225 patients, found 81 patients with type 2 DM and 144 patients without type 2 DM.

Conclusion

AFB smear positive found more in adult pulmonary TB patients with type 2 DM compared to TB patient without type 2 DM. It also found statistically significant between type 2 DM with the AFB smear results on adult pulmonary TB patients.

Association between diabetes mellitus and active tuberculosis: A systematic review and meta-analysis

The burgeoning epidemic of diabetes mellitus (DM) is one of the major global health challenges. We systematically reviewed the published literature to provide a summary estimate of the association between DM and active tuberculosis (TB). We searched Medline and EMBASE databases for studies reporting adjusted estimates on the TB–DM association published before December 22, 2015, with no restrictions on region and language. In the meta-analysis, adjusted estimates were pooled using a DerSimonian-Laird random-effects model, according to study design. Risk of bias assessment and sensitivity analyses were conducted. 44 eligible studies were included, which consisted of 58,468,404 subjects from 16 countries. Compared with non-DM patients, DM patients had 3.59–fold (95% confidence interval (CI) 2.25–5.73), 1.55–fold (95% CI 1.39–1.72), and 2.09–fold (95% CI 1.71–2.55) increased risk of active TB in four prospective, 16 retrospective, and 17 case-control studies, respectively. Country income level (3.16–fold in low/middle–vs. 1.73–fold in high–income countries), background TB incidence (2.05–fold in countries with >50 vs. 1.89–fold in countries with ≤50 TB cases per 100,000 person-year), and geographical region (2.44–fold in Asia vs. 1.71–fold in Europe and 1.73–fold in USA/Canada) affected appreciably the estimated association, but potential risk of bias, type of population (general versus clinical), and potential for duplicate data, did not. Microbiological ascertainment for TB (3.03–fold) and/or blood testing for DM (3.10–fold), as well as uncontrolled DM (3.30–fold), resulted in stronger estimated association. DM is associated with a two- to four-fold increased risk of active TB. The association was stronger when ascertainment was based on biological testing rather than medical records or self-report. The burgeoning DM epidemic could impact upon the achievements of the WHO “End TB Strategy” for reducing TB incidence.

Diabetes and Tuberculosis

The increase in type 2 diabetes mellitus (DM) patients in countries where tuberculosis (TB) is also endemic has led to the reemerging importance of DM as a risk factor for TB. DM causes a 3-fold increase in TB risk and a 2-fold increase in adverse TB treatment outcomes. Given the sheer numbers of DM patients worldwide, there are now more TB patients with TB-DM comorbidity than TB-HIV coinfection. There is an urgent need to implement strategies for TB prevention and control among the millions of DM patients exposed to Mycobacterium tuberculosis. This chapter summarizes the current epidemiological, clinical, and immunological knowledge on TB and DM and their clinical and public health implications. These include the underlying mechanisms for TB risk in DM patients and their clinical and sociodemographic characteristics that distinguish them from TB patients without DM. TB-DM comorbidity is posing a new challenge for integrating the short-term care for TB with the long-term care for DM, particularly in low- and middle-income countries.

IL-6 and IL-18 cytokine gene variants of pulmonary tuberculosis patients with co-morbid diabetes mellitus and their household contacts in Hyderabad

PURPOSE

Association of cytokine genes reflects their susceptibility towards infection and disease in household contacts (HHC) of pulmonary tuberculosis (PTB) patients. Hyperglycemia, a common factor in diabetics might influence their risk towards mycobacterium tuberculosis infection and disease development. This study determines the association of IL-6 and IL-18 cytokine gene variants of TB patients with diabetes mellitus (TBDM) and their HHC in Hyderabad.

METHODS

Single nucleotide polymorphisms of IL-6 (-174 G>C and -572 G>C) and IL-18 (-137 G>C and -607 C>A) cytokine genes were genotyped by Amplification Refractory Mutation System and Restriction Fragment Length polymerase chain reaction in total of 705 subjects comprising of TBDM, their HHC, PTB, DM and Healthy controls (HC).

RESULTS

At IL-6 -174G>C variant, GG genotype, G allele in TBDM and TBDM HHC, at -572G>C variant, C allele in TBDM and GG haplotype in TBDM HHC were showing positive association, however DM have not shown any association at IL-6 polymorphic sites. With respect to the IL-18 gene polymorphisms, at -137 G>C variant, GG genotype was positively associated in PTB while at -607 C>A variant positive association was shown with AC genotype in TBDM, their HHC and DM; GACC diplotype in TBDM and GCGC in PTB.

CONCLUSION

Our findings suggest that susceptible combination of IL-6 and IL-18 cytokine genes associated with disease in the HHCs highlight their risk of inclination towards the disease.

Prevalence and Impact of Diabetes Mellitus Among Patients with Active Pulmonary Tuberculosis in South Korea

OBJECTIVE

South Korea has an increasing prevalence of diabetes and a relatively high burden of tuberculosis. We aimed to determine the prevalence of diabetes in patients with active pulmonary tuberculosis (PTB) and examine the effect of diabetes on tuberculosis treatment outcomes.

SETTING AND DESIGN

Data from patients ≥30 years diagnosed with and treated for PTB between January 2010 and December 2012 at Severance Hospital, a 2000-bed tertiary referral hospital in Seoul, South Korea, were analyzed and compared with data from a contemporaneous general population sample extracted from KNHANES V.

RESULTS

Diabetes prevalence was 24.2% (252/1044) among patients with PTB and 11.6% (1700/14,655) among controls. Diabetes [odds ratios (OR) 2.56, 95% confidence interval (CI) 1.56-4.21, P < 0.001], male sex (OR 1.93, 95% CI 1.08-3.44, P = 0.027), and cavitary disease (OR 2.08, 95% CI 1.29-3.35, P = 0.003) were significant risk factors for 2-month culture positivity. Diabetes was the only factor associated with unsuccessful treatment outcomes (OR 1.67, 95% CI 1.03-2.70, P = 0.039).

CONCLUSION

The prevalence of diabetes was markedly higher in patients with PTB than in a sample of the general South Korean population. Diabetes may delay sputum conversion and adversely affect treatment outcomes; detection and management of diabetes in patients with PTB is crucial.

Anti-mycobacterial function of macrophages is impaired in a diet induced model of type 2 diabetes

Type 2 diabetes (T2D) is one of the major risk factors for tuberculosis (TB). In this study, a diet induced murine model of T2D (DIMT2D) was developed and characterized in the context of metabolic, biochemical and histopathological features following diet intervention. Mycobacterial susceptibility was investigated using Mycobacterium fortuitum as a surrogate. Phagocytic capability of alveolar macrophages and resident peritoneal macrophages were determined by in vitro assays using mycolic acid coated beads and M. fortuitum. Results demonstrated that bacillary loads were significantly higher in liver, spleen, and lungs of diabetic mice compared to controls. Higher inflammatory lesions and impaired cytokine kinetics (TNF-α, MCP-1, IL-12, IFN-γ) were also observed in diabetic mice. Macrophages isolated from diabetic mice had lower uptake of mycolic acid coated beads, reduced bacterial internalization and killing and altered cytokine responses (TNF-α, IL-6, MCP-1). This model will be useful to further investigate different facets of host-pathogen interactions in TB-T2D.

Profile of glycated-hemoglobin, antioxidant vitamin and cytokine levels in pulmonary tuberculosis patients: A cross sectional study at Pulmonary Diseases Center Semarang City, Indonesia

Background

Uncontrolled blood glucose, which marked by high level of HbA1c, increases risk of pulmonary TB because of cellular immunity dysfunction. This study aimed to analyze profile of glycated hemoglobin, antioxidant vitamins status and cytokines levels in active pulmonary TB patients.

Methods

This was a cross sectional study, conducted at Pulmonary Diseases Center Semarang City, Indonesia. Study subject consisted of 62 pulmonary TB patients, diagnosed with positive acid fast bacilli and chest X-ray. ELISA was used to measure IFN-γ and IL-12. Status of antioxidant vitamins was determined by concentration of vitamin A and E using HPLC. Blood glucose control was determined by HbA1c concentration (HbA1c ≥7% is considered as uncontrolled).

Results

A significant difference of age between pulmonary tuberculosis patients with normal and uncontrolled blood glucose (p = 0.000) was showed, while all other characteristics (sex, education, occupation) did not differ with p = 0.050, 0.280, 0.380 respectively. Mean HbA1c was 7.25 ± 2.70%. Prevalence of uncontrolled glucose among pulmonary TB patients was 29%. Levels of IFN-γ and IL-12 did not differ according to HbA1c concentration (p = 0.159 and p = 0.965 respectively). Pulmonary tuberculosis patients with uncontrolled blood glucose has higher vitamin E (p = 0.006), while vitamin A did not differ significantly (p = 0.478).

Conclusions

This study supports the importance of performing diabetes screening among pulmonary TB patients. Further study needs to be done to determine the feasibility of TB-DM co-management.

Metabolic reprogramming & inflammation: Fuelling the host response to pathogens

Successful immune responses to pathogens rely on efficient host innate processes to contain and limit bacterial growth, induce inflammatory response and promote antigen presentation for the development of adaptive immunity. This energy intensive process is regulated through multiple mechanisms including receptor-mediated signaling, control of phago-lysomal fusion events and promotion of bactericidal activities. Inherent macrophage activities therefore are dynamic and are modulated by signals and changes in the environment during infection. So too does the way these cells obtain their energy to adapt to altered homeostasis. It has emerged recently that the pathways employed by immune cells to derive energy from available or preferred nutrients underline the dynamic changes associated with immune activation. In particular, key breakpoints have been identified in the metabolism of glucose and lipids which direct not just how cells derive energy in the form of ATP, but also cellular phenotype and activation status. Much of this comes about through altered flux and accumulation of intermediate metabolites. How these changes in metabolism directly impact on the key processes required for anti-microbial immunity however, is less obvious. Here, we examine the 2 key nutrient utilization pathways employed by innate cells to fuel central energy metabolism and examine how these are altered in response to activation during infection, emphasising how certain metabolic switches or 'reprogramming' impacts anti-microbial processes. By examining carbohydrate and lipid pathways and how the flux of key intermediates intersects with innate immune signaling and the induction of bactericidal activities, we hope to illustrate the importance of these metabolic switches for protective immunity and provide a potential mechanism for how altered metabolic conditions in humans such as diabetes and hyperlipidemia alter the host response to infection.

The effect of diabetes control status on treatment response in pulmonary tuberculosis: a prospective study

BACKGROUND

Uncontrolled diabetes, unlike controlled diabetes, is associated with an impaired immune response. However, little is known about the impact of the status of diabetes control on clinical features and treatment outcomes in patients with pulmonary TB (PTB). We conducted this study to evaluate whether the status of diabetes control influences clinical manifestations and treatment responses in PTB.

METHODS

A multicentre prospective study was performed between September 2012 and September 2014. The patients were categorised into three groups according to the glycated haemoglobin (HbA1C) level: PTB without diabetes mellitus (non-DM), PTB with controlled diabetes (controlled-DM) and PTB with uncontrolled diabetes (uncontrolled-DM). The primary outcome was the sputum culture conversion rate after 2 months of intensive treatment.

RESULTS

Among 661 patients with PTB, 157 (23.8%) had diabetes and 108 (68.8%) had uncontrolled diabetes (HbA1C≥7.0%). The uncontrolled-DM group exhibited more symptoms, positive sputum smears (p<0.001) and presence of cavities (p<0.001) than the non-DM group. Regarding treatment responses, patients with uncontrolled-DM were more likely to have a positive culture after 2 months (p=0.009) and either treatment failure (p=0.015) or death (p=0.027) compared with the non-DM group. In contrast, those with controlled-DM showed similar treatment responses to the non-DM group. In multivariable analysis, uncontrolled diabetes was an independent risk factor for a positive sputum culture after 2 months of treatment (adjusted OR, 2.11; p=0.042) and either treatment failure or death (adjusted OR, 4.11; p=0.022).

CONCLUSIONS

Uncontrolled diabetes is an independent risk factor for poor treatment response in PTB.

Glycemic Control and the Risk of Tuberculosis: A Cohort Study

BACKGROUND

Diabetes is a well-known risk factor for tuberculosis (TB) and is increasingly prevalent in low- and middle-income countries, where the burden of TB is high. Glycemic control has the potential to modify the risk of TB. However, there are few studies on the association between glycemic control and TB risk, and the results are inconsistent.

METHODS AND FINDINGS

We assembled a cohort using 123,546 individuals who participated in a community-based health screening service in northern Taiwan from 5 March 2005 to 27 July 2008. Glycemic control was measured using fasting plasma glucose (FPG) at the time of screening. The cohort was followed up to 31 December 2012 for the occurrence of TB by cross-matching the screening database to the national health insurance database. Multiple imputation was used to handle missing information. During a median follow-up of 4.6 y, 327 cases of TB occurred. In the multivariable Cox regression model, diabetic patients with poor glycemic control (FPG > 130 mg/dl) had a significantly higher hazard of TB (adjusted hazard ratio [aHR] 2.21, 95% CI 1.63-2.99, p < 0.001) compared to those without diabetes. The hazard of TB in diabetic patients with good glycemic control (FPG ≤ 130 mg/dl) did not differ significantly from that in nondiabetic individuals (aHR 0.69, 95% CI 0.35-1.36, p = 0.281). In the linear dose-response analysis, the hazard of TB increased with FPG (aHR 1.06 per 10-mg/dl increase in FPG, 95% CI 1.03-1.08, p < 0.001). Assuming the observed association between glycemic control and TB was causal, an estimated 7.5% (95% CI 4.1%-11.5%) of incident TB in the study population could be attributed to poor glycemic control. Limitations of the study include one-time measurement of fasting glucose at baseline and voluntary participation in the health screening service.

CONCLUSIONS

Good glycemic control could potentially modify the risk of TB among diabetic patients and may contribute to the control of TB in settings where diabetes and TB are prevalent.

Incidence of and Risk Factors for Tuberculosis (TB) in Gastric Cancer Patients in an Area Endemic for TB: A Nationwide Population-based Matched Cohort Study

To date, there have been few reports investigating the relationship between tuberculosis (TB) and gastric cancer.We conducted a nationwide population-based matched cohort study using data retrieved from Taiwan's National Health Insurance Research Database to determine the incidence of and risk factors for TB in patients diagnosed with gastric cancer. From 2000 to 2011, we identified 36,972 gastric cancer patients and normal subjects from the general population matched for age, sex, and comorbidities at a 1:1 ratio. The data were analyzed using Cox proportional hazards models.Compared with the matched cohort, gastric cancer patients exhibited a higher risk for TB (adjusted hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.65-3.05, P < 0.001), and those with TB exhibited higher mortality (adjusted HR 1.59, 95% CI 1.41-1.79, P < 0.001). Old age (adjusted HR 2.40, 95% CI 1.92-2.99, P < 0.001), male sex (adjusted HR 2.13, 95% CI 1.76-2.57, P < 0.001), diabetes mellitus (adjusted HR 1.28, 95% CI 1.05-1.56, P = 0.013), and chronic obstructive pulmonary disease (COPD) (adjusted HR 1.44, 95% CI 1.19-1.75, P < 0.001) were identified as independent risk factors for TB in gastric cancer patients. Dyslipidemia was an independent protective factor for both TB (adjusted HR 2.13, 95% CI 1.73-2.62, P < 0.001) and mortality (adjusted HR 1.11, 95% CI 1.08-1.15, P < 0.001) in gastric cancer patients.Old age, male sex, diabetes mellitus, and COPD were independent risk factors for TB in gastric cancer. High-risk gastric cancer patients, especially those in TB-endemic areas, should be regularly screened for TB.

Intravenous Mycobacterium Bovis Bacillus Calmette-Guérin Ameliorates Nonalcoholic Fatty Liver Disease in Obese, Diabetic ob/ob Mice

Inflammation and immune response profoundly influence metabolic syndrome and fatty acid metabolism. To analyze influence of systemic inflammatory response to metabolic syndrome, we inoculated an attenuated vaccine strain of Mycobacterium bovis Bacillus Calmette–Guérin (BCG) into leptin-deficient ob/ob mice. BCG administration significantly decreased epididymal white adipose tissue weight, serum insulin levels, and a homeostasis model assessment of insulin resistance. Serum high molecular weight (HMW) adiponectin level and HMW/total adiponectin ratio of the BCG treated mice were significantly higher than those of control mice. Hepatic triglyceride accumulation and macrovesicular steatosis were markedly alleviated, and the enzymatic activities and mRNA levels of lipogenic-related genes in liver were significantly decreased in the BCG injected mice. We also exposed human hepatocellular carcinoma HepG2 cells to high levels of palmitate, which enhanced endoplasmic reticulum stress-related gene expression and impaired insulin-stimulated Akt phosphorylation (Ser473). BCG treatment ameliorated both of these detrimental events. The present study therefore suggested that BCG administration suppressed development of nonalcoholic fatty liver disease, at least partly, by alleviating fatty acid-induced insulin resistance in the liver.

Immunological mechanisms contributing to the double burden of diabetes and intracellular bacterial infections

Diabetes has been recognized as an important risk factor for a variety of intracellular bacterial infections, but research into the dysregulated immune mechanisms contributing to the impaired host-pathogen interactions is in its infancy. Diabetes is characterized by a chronic state of low-grade inflammation due to activation of pro-inflammatory mediators and increased formation of advanced glycation end products. Increased oxidative stress also exacerbates the chronic inflammatory processes observed in diabetes. The reduced phagocytic and antibacterial activity of neutrophils and macrophages provides an intracellular niche for the pathogen to replicate. Phagocytic and antibacterial dysfunction may be mediated directly through altered glucose metabolism and oxidative stress. Furthermore, impaired activation of natural killer cells contributes to decreased levels of interferon-γ, required for promoting macrophage antibacterial mechanisms. Together with impaired dendritic cell function, this impedes timely activation of adaptive immune responses. Increased intracellular oxidation of antigen-presenting cells in individuals with diabetes alters the cytokine profile generated and the subsequent balance of T-cell immunity. The establishment of acute intracellular bacterial infections in the diabetic host is associated with impaired T-cell-mediated immune responses. Concomitant to the greater intracellular bacterial burden and potential cumulative effect of chronic inflammatory processes, late hyper-inflammatory cytokine responses are often observed in individuals with diabetes, contributing to systemic pathology. The convergence of intracellular bacterial infections and diabetes poses new challenges for immunologists, providing the impetus for multidisciplinary research.

Impact of diabetes on the natural history of tuberculosis

Tuberculosis (TB) is the number one bacterial killer worldwide and the current increase in type 2 diabetes mellitus patients (DM), particularly in countries where TB is also endemic, has led to the re-emerging importance of DM2 as a risk factor for TB. There is an urgent need to implement strategies for TB prevention among the millions of DM patients exposed to Mycobacterium tuberculosis (Mtb) worldwide, but knowledge is limited on how and when DM2 alters the natural history of this infection. In this review we summarize the current epidemiological, clinical and immunologic studies on TB and DM and discuss the clinical and public health implications of these findings. Specifically, we evaluate the mechanisms by which DM patients have a higher risk of Mtb infection and TB development, present with signs and symptoms indicative of a more infectious TB infection, and are more likely to have adverse TB treatment outcomes, including death. Emphasis is placed on type 2 DM given its higher prevalence in contemporary times, but the underlying role of hyperglycemia and of type 1 DM is also discussed.

The effect of diabetes and undernutrition trends on reaching 2035 global tuberculosis targets

To achieve the post-2015 global tuberculosis target of 90% reduction in tuberculosis incidence by 2035, the present rate of decline must accelerate. Among factors that hinder tuberculosis control, malnutrition and diabetes are key challenges. We review available data to describe the complex relationship between tuberculosis, diabetes, and nutritional status. Additionally, we review past trends, present burden, and available future global projections for diabetes, overweight and obesity, as well as undernutrition and food insecurity. Using a mathematical model, we estimate the potential effect of these factors on tuberculosis burden up to 2035. Great potential exists for reduction of worldwide tuberculosis burden by combination of improved prevention and care of diabetes with reduction of undernutrition. To achieve this combination will require joint efforts and strong cross-programme links, enabling synergistic effects of public health policies that promote good nutrition and optimum clinical care for tuberculosis and diabetes.

The double burden: a new-age pandemic meets an ancient infection

Tuberculosis is responsible for significant morbidity and mortality in the tropics. Active TB develops when host defences are impaired. Epidemiological evidence and studies addressing the double burden of communicable and non-communicable diseases demonstrate a clear association between diabetes and susceptibility to TB, treatment failure and complications. The immune mechanisms involved in host-pathogen interactions in co-morbid TB-diabetes are not well defined and require further investigation. This combined with the increase in diabetes predominately in low- and middle-income countries where TB is prevalent has major health implications.

Is resistance to anti-tuberculosis drugs associated with type 2 diabetes mellitus? A register review in Beijing, China

BACKGROUND

China has a high burden of drug-resistant tuberculosis (TB) and diabetes mellitus (DM).

OBJECTIVE

The objectives of this study were to determine the following in patients with culture-confirmed TB: 1) demographic characteristics and disease patterns in relation to the presence or absence of type 2 diabetes and 2) presence or absence of drug resistance to isoniazid (INH), rifampicin (RMP) or both in relation to duration of diabetes and control of diabetes.

DESIGN

This is a cross-sectional and retrospective study involving record reviews.

RESULTS

There were 621 patients with culture-positive TB, of whom 187 (30%) had previously known or new type 2 diabetes. In those with diabetes, there was a significantly higher proportion of males, persons aged ≥35 years and patients registered with new TB (p<0.05). Prevalence of multidrug-resistant TB (MDR-TB) was 6.2% in new patients (N=422) and 62.3% in previously treated patients (N=199), with no significant differences between those with and without diabetes. In patients with diabetes, there was no association of drug resistance with diabetes duration or disease control [assessed by fasting blood glucose (FBG) at 1 week].

CONCLUSION

A high proportion of patients with TB in a tertiary health facility, Beijing, China, had diabetes, but there was no association between type 2 diabetes and drug-resistant TB. Further prospective studies are needed to confirm these findings.

Glycemic control and radiographic manifestations of tuberculosis in diabetic patients

BACKGROUND

Radiographic manifestations of pulmonary tuberculosis (TB) in patients with diabetes mellitus (DM) have previously been reported, with inconsistent results. We conducted a study to investigate whether glycemic control has an impact on radiographic manifestations of pulmonary TB.

METHODS

Consecutive patients with culture-positive pulmonary TB who had DM in three tertiary care hospitals from 2005-2010 were selected for review and compared with a similar number without DM. Glycemic control was assessed by glycated haemoglobin A1C (HbA1C). A pre-treatment chest radiograph was read independently by two qualified pulmonologists blinded to patients' diabetic status. Films with any discordant reading were read by a third reader.

RESULTS

1209 culture positive pulmonary TB patients (581 with DM and 628 without DM) were enrolled. Compared with those without DM, TB patients with DM were significantly more likely to have opacity over lower lung fields, extensive parenchymal lesions, any cavity, multiple cavities and large cavities (>3 cm). The relative risk of lower lung field opacities was 0.80 (95% CI 0.46-1.42) for those with DM with A1C<7%, 2.32 (95% CI 1.36 - 3.98) for A1C 7%-9%, and 1.62 (95% CI 1.12-2.36) for A1C>9%; and that of any cavity over no cavity was 0.87 (95% CI 0.46-1.62) for patients with DM with A1C<7%, 1.84 (95% CI 1.20-2.84) for A1C 7%-9%, and 3.71 (95% CI 2.64-5.22) for A1C>9%, relative to patients without DM.

CONCLUSIONS

Glycemic control significantly influenced radiographic manifestations of pulmonary TB in patients with DM.

Diabetes and risk of tuberculosis relapse: nationwide nested case-control study

The aim of this study was to investigate the association between diabetes mellitus (DM) and tuberculosis (TB) relapse using the nationwide TB registry in Taiwan. We conducted a case-control study nested within a nationwide cohort of all incident cases of pulmonary TB that were notified during 2006–2007 and had completed anti-TB treatment. The relapse of TB was confirmed by bacteriological or pathological findings. For each relapse case, one control was selected from the study cohort matching by time since treatment completion. DM status was ascertained by medical chart review and cross-matching with the National Health Insurance claims database. A total of 305 cases of relapse were identified after a median follow-up of 3 years (relapse rate: 488 per 100,000 person-year; 95% confidence interval (CI): 434–546). Presence of DM during previous anti-TB treatment was 34.0% and 22.7% in cases and controls, respectively. After adjusting for other potential confounders, DM was associated with increased risk of TB relapse (adjusted odds ratio: 1.96, 95% CI: 1.22–3.15). Only one-third of the DM-TB patients in our study received glycaemic monitoring using HbA1c during anti-TB treatment. Presence of DM was independently associated with risk of TB relapse. TB programs should seriously consider rigorous glucose control in DM-TB patients.

Diabetes and immunity to tuberculosis

The dual burden of tuberculosis (TB) and diabetes has attracted much attention in the past decade as diabetes prevalence has increased dramatically in countries already afflicted with a high burden of TB. The confluence of these two major diseases presents a serious threat to global public health; at the same time it also presents an opportunity to learn more about the key elements of human immunity to TB that may be relevant to the general population. Some effects of diabetes on innate and adaptive immunity that are potentially relevant to TB defense have been identified, but have yet to be verified in humans and are unlikely to fully explain the interaction of these two disease states. This review provides an update on the clinical and epidemiological features of TB in the diabetic population and relates them to recent advances in understanding the mechanistic basis of TB susceptibility and other complications of diabetes. Issues that merit further investigation - such as geographic host and pathogen differences in the diabetes/TB interaction, the role of hyperglycemia-induced epigenetic reprogramming in immune dysfunction, and the impact of diabetes on lung injury and fibrosis caused by TB - are highlighted in this review.

Host-pathogen interactions in tuberculosis patients with type 2 diabetes mellitus

Tuberculosis (TB) is known to be fueled by HIV as well as social and economic factors. With progression of the diabetes mellitus (DM) pandemic in countries where TB is also endemic, focus is increasing on the potential links between DM and TB. Despite the magnitude of the DM-TB association worldwide, it is striking how little we know about the underlying biology that promotes this association which is a major concern to public health. In this review we summarize current findings regarding the alterations in the innate and adaptive immune responses of DM patients to Mycobacterium tuberculosis (Mtb). Current findings suggest underperforming innate immunity followed by a hyper-reactive cellular response to Mtb, but the contribution of these altered responses to TB susceptibility or to the more adverse clinical outcomes of TB patients with DM remains unclear. Elucidating the basic mechanisms underlying the higher susceptibility of DM patients to TB should lead to a strategy for stratification of the millions of DM patients worldwide into those with the highest TB risk for targeted TB prevention.

Obesity, diabetes and pneumonia: the menacing interface of non-communicable and infectious diseases

OBJECTIVES

To review current knowledge on the epidemiological, clinical and biological impact of the pandemic of obesity and diabetes on pneumonias.

METHODS

We conducted a literature review using PubMed and EMBASE, supplemented by various sources. Given the disparate and fragmented nature of the literature, a formal systematic review was not possible.

RESULTS

In 2008, globally 10% of men and 14% of women were obese and an estimated 371 million had diabetes; half undiagnosed and many obese. Numbers are rising rapidly in low- and middle-income countries where the majority reside, but reliable data are lacking. The most frequent pneumonias in obesity and diabetes are tuberculosis, influenza and pneumococcal, staphylococcal and opportunistic pathogens. Diabetes impacts tuberculosis control and increases drug resistance and mortality. Mortality and morbidity from pneumococcal pneumonia and influenza are increased in obesity and diabetes. In addition to mechanical and physiological effects, there are considerable immunological abnormalities characterised by chronic, low-grade inflammation. Simultaneous up-regulation and dysregulation of both innate and adaptive immune responses impair control and killing of invading organisms. Prevention in those at risk is poorly practised, although screening for tuberculosis in diabetes is beginning in high-burden settings.

CONCLUSIONS

Pneumonia is a threat globally in obesity and diabetes with increased incidence and severity of disease. There is uncertainty about whether vaccines are equally effective in those with obesity and diabetes. Increased epidemiological, clinical and biological knowledge will be crucial to face this 21st century challenge.

The double burden of diabetes and tuberculosis - public health implications

Diabetes mellitus (DM) and tuberculosis (TB) have existed for thousands of years and even now the global disease burden from DM and TB is huge. The incidence of TB is declining slowly but it still remains a big problem in many populous large low and middle income countries. On the other, hand the burden of diabetes is increasing very rapidly, particularly in the very same countries where TB is endemic. The intersecting double burden is therefore ominous particularly as several studies and systematic reviews have indicated that DM increases the risk of TB disease and results in poor treatment outcomes. To address the double burden, WHO and the International Union Against Tuberculosis and Lung Disease (The Union) in 2011 launched a collaborative framework for the care and control of diabetes and tuberculosis, to encourage collaborative research and implement bidirectional screening of the two diseases in routine settings. This review article (i) explores some of the new evidence for the association between TB and DM, (ii) discusses issues with regard to clinical presentation and outcomes, (iii) presents the evidence, challenges and strategies for bidirectional screening based on field studies to implement the framework and (iv) finally presents suggestions on how diabetes care delivery may benefit from the lessons of the TB DOTS approach and public health principles for structured care delivery.

Impact of diabetes on treatment outcomes and long-term survival in multidrug-resistant tuberculosis

BACKGROUND

Few studies have investigated the impact of diabetes mellitus (DM), a globally increasing metabolic disease, on treatment outcomes and long-term survival in patients with multidrug-resistant forms of tuberculosis (MDR-TB).

OBJECTIVES

We analyzed outcomes in a large cohort to assess the impact of DM on treatment outcomes of patients with MDR-TB.

METHODS

MDR-TB patients newly diagnosed or retreated between 2000 and 2002 and followed for 8-11 years were retrospectively analyzed with respect to the effect of DM as a comorbidity on their treatment outcome and long-term survival.

RESULTS

Of 1,407 patients with MDR-TB, 239 (17.0%) had coexisting DM. The mean age and body mass index were higher in MDR-TB patients with DM [MDR-TBDM(+)] than in those without DM [MDR-TBDM(-)]. Patients with MDR-TB and a comorbidity of DM had a significantly lower treatment success rate than those without a history of DM (36.0 vs. 47.2%, p = 0.002). In addition, DM was the negative predictor for MDR-TB treatment success in multivariate analyses [odds ratio 0.51, 95% confidence interval (CI) 0.26-0.99]. Mean survival times were also lower in MDR-TBDM(+) than in MDR-TBDM(-) patients (102 vs. 114 months, p = 0.001), with DM as a significant predictor of poor long-term survival in multivariate analyses (hazard ratio 1.59, 95% CI 1.01-2.50).

CONCLUSIONS

Among MDR-TB patients, DM was a relatively common comorbidity. In patients undergoing treatment for MDR-TB and followed for 8-11 years, it was found to be independently associated with an increased risk of both treatment failure and death.

Smear positive pulmonary tuberculosis among diabetic patients at the Dessie referral hospital, Northeast Ethiopia

Background

Tuberculosis (TB) is an infectious disease which is still a major cause of morbidity and mortality throughout the world. People with diabetes mellitus (DM) have a three times higher risk of developing active TB than people without diabetes. However, there is not enough credible information on the burden of pulmonary tuberculosis (PTB) among DM patients in Ethiopia, in general, and in the city of Dessie, in particular. Therefore, this study aims to determine the prevalence and associated risk factors of smear positive PTB among diabetic patients at a referral hospital in Dessie.

Methods

A cross-sectional study was conducted from February 2012 to April 2012. Patient demographic characteristics were collected using a pre-tested standard questionnaire format. Spot-morning-spot sputum specimens were collected from the study participants and examined for acid-fast bacilli using direct microscopy by the Ziehl-Neelsen staining technique. Data was entered and analyzed using the SPSS version 16 statistical software and p-value <0.05 was considered as statistically significant.

Results

Out of 225 TB suspected diabetic patients, 52% were males and 48% were females. Their ages ranged from 12 to 82 years, with a mean age of 47.2 years. Urban residence (AOR: 5.5; 95% CI: 1.07–28.20), history of TB (AOR: 13.4; 95% CI: 2.74–65.73), contact with TB patients in the family (AOR: 9.4; 95% CI: 1.822–48.50), and long duration of DM (AOR: 8.89; 95% CI: 1.88–58.12) were independently associated with the development of active TB in people living with DM.

Conclusions

The prevalence of smear positive PTB was 6.2% in TB suspected diabetic patients, which is higher compared with the general population (0.39%). Patients with a previous history of contact with TB patients, as well as those who had prolonged diabetes, were more prone to have PTB. Therefore, screening of diabetic patients for PTB infection during follow-up is necessary.

The effect of combination IFN-alpha-2a with usual antituberculosis chemotherapy in non-responding tuberculosis and diabetes mellitus: a case report and review of the literature

A limited number of publications indicate that certain interferons (IFNs) may have a role in difficult-to-treat tuberculosis. We present a 48-year-old male diabetic patient who was referred to our department with the presumptive diagnosis of multidrug resistant tuberculosis. During the previous 8 months, he had been treated initially with a four-drug regimen (rifampicin, isoniazid, pyrazinamide, and ethambutol), which was later modified by the addition of streptomycin and ciprofloxacin, but his clinical condition had not improved and his sputum smear microscopy had remained positive to acid-fast bacilli. Cultured Mycobacterium tuberculosis from his sputum was sensitive to rifampicin and isoniazid. We administered IFN-alpha-2a at a low dose of 3 million IU intramuscularly weekly, in combination with isoniazid, rifampicin, ethambutol, and pyrazinamide. Two months after initiation of this therapy, sputum smears became negative, and a dramatic improvement in the patient's clinical and radiological findings occurred. During a 4-year follow-up, all consecutive sputum cultures remain negative. This case provides additional confirmation that certain IFNs could, potentially, be useful as therapeutic adjuncts for selected cases of non-responding tuberculosis and, therefore, merit further consideration.

Screening and intervention of diabetes mellitus in patients with pulmonary tuberculosis in poverty zones in China: rationale and study design

BACKGROUND

The merging epidemics of pulmonary tuberculosis (PTB) and diabetes mellitus (DM) have been raised concerns by many experts but no large scale screening and intervention have been launched yet, especially in low-income areas. The current study aims to understand the prevalence of DM in active PTB patients and evaluate the outcomes of diet and living habit intervention in poverty zones in China.

METHODS/DESIGN

A cross-sectional investigation and intervention study will be carried out. At least 7000 active PTB patients will be recruited, together with 7000 nonTB persons from the same community. The project will be divided into two stages. The first stage is to train TB workers on DM screening and regular treatment. Screening and related investigation will be carried out afterwards. The second stage is focussed on intervention. A comprehensive strategy will be utilized to conduct health promotion among the patients, the health providers and the lay public.

DISCUSSION

To our knowledge, this is the first and largest study which focuses on the prevalence of DM in PTB in China. We hypothesize that the current prevalence of DM in PTB in China will be understood and the results of our study will provide important evidence for preventing and controlling DM and PTB.