Influence of diabetes mellitus on immunity to human tuberculosis

Dysglycaemia among tuberculosis patients without known diabetes in a low-endemic setting

There is increasing evidence that diabetes mellitus is an important risk factor for tuberculosis (TB) and might affect TB-disease presentation as well as treatment response [1]. The hypothesis is that an impaired immune response in persons with diabetes mellitus facilitates infection with Mycobacterium tuberculosis and/or progression to TB, and reversely, M. tuberculosis infection may affect glycaemic control [2, 3]. Although the exact causality is unknown, this association between TB and diabetes mellitus is ominous, as the explosive rise in diabetes mellitus worldwide witnessed over the last decades could potentially counteract the positive effect of TB control efforts.

With a high prevalence of dysglycaemia (29.1%) among tuberculosis patients without previously known diabetes, this study highlights the importance of comanagement of tuberculosis and diabetes, even in a low-endemic settinghttps://bit.ly/3Gj0gmN

The Effect of Diabetes and Prediabetes on Antituberculosis Treatment Outcomes: A Multicenter Prospective Cohort Study

BACKGROUND

It is unclear whether diabetes or prediabetes affects unfavorable treatment outcomes and death in people with tuberculosis (PWTB).

METHODS

Culture-confirmed, drug-susceptible PWTB, enrolled in the Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil cohort between 2015 and 2019 (N = 643) were stratified based on glycemic status according to baseline glycated hemoglobin. Unfavorable tuberculosis (TB) outcome was defined as treatment failure or modification, recurrence, or death; favorable outcome was cure or treatment completion. We corroborated the findings using data from PWTB reported to the Brazilian National System of Diseases Notification (SINAN) during 2015-2019 (N = 20 989). Logistic regression models evaluated associations between glycemic status and outcomes.

RESULTS

In both cohorts, in univariate analysis, unfavorable outcomes were more frequently associated with smoking, illicit drug use, and human immunodeficiency virus infection. Diabetes, but not prediabetes, was associated with unfavorable outcomes in the RePORT-Brazil (adjusted relative risk [aRR], 2.45; P < .001) and SINAN (aRR, 1.76; P < .001) cohorts. Furthermore, diabetes was associated with high risk of death (during TB treatment) in both RePORT-Brazil (aRR, 2.16; P = .040) and SINAN (aRR, 1.93; P = .001).

CONCLUSIONS

Diabetes was associated with an increased risk of unfavorable outcomes and mortality in Brazilian PWTB. Interventions to improve TB treatment outcomes in persons with diabetes are needed.

High Vitamin D Concentrations Restore the Ability to Express LL37 by M. tuberculosis-Infected Human Macrophages

Vitamin D has an immunomodulatory function and is involved in eliminating pathogens. Vitamin D deficiencies reported in Type 2 diabetes mellitus (T2DM) patients make them more susceptible to developing tuberculosis (TB). The macrophages are the immune cells that control intracellular pathogens by producing the antimicrobial peptide cathelicidin-LL37. This pathway involves TLR activation by pathogens, vitamin D receptor (VDR) ligation, and the enzyme 1α-hydroxylase Cytochrome P450 Family 27 Subfamily B Member 1 (CYP27B1). However, it is not clear whether the biological actions of vitamin D are affected by high glucose concentrations. This study aimed to evaluate the vitamin D contribution in the expression of VDR and CYP27B1, involved in the conversion of an inactive to an active form of vitamin D in the infected macrophages using M. tuberculosis as an infection model. The expression of LL37 and the nucleus translocation of VDR were evaluated as the readout of the response of vitamin D and determined if those processes are affected by glucose concentrations. Macrophages from healthy donors were cultured under glucose concentrations of 5.5, 15, or 30 mM, stimulated with vitamin D in inactive (25(OH)D3) or active (1,25(OH)2D3) forms, and infected with M. tuberculosis. The vitamin D-dependent induction of LL37 and the expression of VDR and CYP27B1 genes were analyzed by qPCR, and VDR translocation was analyzed in nuclear protein extracts by ELISA. M. tuberculosis downregulated the expression of LL37 regardless of the glucose concentration, whereas VDR and CYP27B1 upregulated it regardless of the glucose concentration. After evaluating two concentrations of vitamin D, 1 nM or 1 μM, the high concentration (1 μM) was necessary to restore the induction of LL37 expression in M. tuberculosis-infected macrophages. High concentrations of the inactive form of vitamin D restore the infected macrophages’ ability to express LL37 regardless of the glucose concentration. This finding supports the idea that vitamin D administration in patients with T2DM could benefit TB control and prevention.

The prevalence of diabetes among tuberculosis patients in Denmark

SETTING

It is estimated that 25% of the world's population are infected with Mycobacterium tuberculosis and that 463 million people are living with diabetes mellitus (DM), a number that is increasing. Patients with DM have three times the risk of developing tuberculosis (TB) and there is significant interaction between DM and TB, suggesting that DM affects not only risk of TB but also TB presentation, treatment response and outcome.

OBJECTIVE

The aim was determining the prevalence of DM among TB patients in Denmark and to assess risk factors.

DESIGN

Patient files from all notified TB cases in Denmark from 2009 to 2014 were retrospectively assessed.

RESULTS

In total, 1912 patients were included and 5.0% had DM. Patients with DM were older, had more comorbidities, came from outside Denmark, and had a higher mortality compared to non-DM-patients. None of the patients from Greenland had DM. Patients with low socio-economic status had a low prevalence of DM. We found a higher prevalence of DM among Danish-born < 54 year and migrant ≥ 75 year compared to a Danish background population.

CONCLUSION

We found a higher prevalence of DM among TB patients with known risk factors, and a surprisingly low prevalence among patients with low socioeconomic status and patients from Greenland.

Association of the Coronavirus Disease 2019 Outbreak on the Diabetes Self-Management in Chinese Patients: An Analytical Cross-Sectional Study

BACKGROUND

The coronavirus disease 2019 (COVID-19) outbreak has seriously affected people's lives, especially those with chronic diseases. Diabetes self-management, which plays an important role in glycaemic control and reducing the risk of acute and long-term complications, may be discouraged by social distancing.

PURPOSE

To evaluate the level of self-management activities in Chinese patients with type 2 diabetes mellitus (T2DM) during the COVID-19 pandemic.

PATIENTS AND METHODS

A survey of with 872 patients with T2DM in the inpatient and outpatient departments through face-to-face interviews was conducted from 1 July, 2020 to 30 September, 2020. The main outcome measures were glycaemic control status and level of self-management activities during the pandemic.

RESULTS

In terms of glycaemic control, the data showed that patients with fasting plasma glucose (FPG) < 7.0 mmol/L (36.4%), postprandial plasma glucose (PPG) < 10.0 mmol/L (26.3%), or glycosylated haemoglobin (HbA1c) < 7.0% (18.6%) in our investigation has well-controlled blood glucose level, and 11.9% of patients experienced blood glucose <3.9 mmol/L during the outbreak. The diabetes self-management of Chinese patients decreased and the final diabetes self-management score of the Chinese patients was 3.4 ± 1.45. Patients with higher education, diabetes education, comorbidities, and online consultations had higher diabetes self-management scores (P <0.05). Adherence to diabetes self-management in the normal glycaemic control group was higher than that in the substandard glycaemic control group (P<0.05). Among all participants, 72.1% of the patients reduced the frequency of hospital visits, and 44.8% considered that they had diabetes-related stress during the pandemic. The mean anxiety level score rated by 286 patients was 5.3±2.8.

CONCLUSION

The COVID-19 pandemic has affected diabetes self-management, including substandard glycemic control, increased diabetes-related stress, limited exercise range and medical visits. Therefore, future interventions should focus on the online management of chronic diseases and support online consultation' development and promotion, which can overcome physical distance and provide personalized services conveniently.

The Footprint of Diabetes Mellitus on the Characteristics and Response to Anti-Tuberculous Therapy in Patients with Pulmonary Tuberculosis from Saudi Arabia

Background

Right now, a tuberculosis (TB) and diabetes mellitus (DM) syndemic is re-emerging worldwide. Given the contradictory results of the impact of DM on the natural history of pulmonary TB (PTB), this study was undertaken to shed light on the precision of this hypothesis from a community with a substantial caseload of both diseases.

Methods

The present 5-year, retrospective, cohort study involved 487 (60.8% males, and 39.2% females) adult PTB patients (mean age 53.71 ± 15.78 years) selected from Dr. Soliman Fakeeh Hospital (DSFH), Jeddah, Kingdom of Saudi Arabia (KSA). The relevant patients' clinical, radiological and microbiological data were extracted from the hospital medical and laboratory database.

Results

In our study, the cumulative prevalence of DM among PTB subjects was 27.1%. Both diabetic and non-diabetic groups were matched with regard to gender (p = 0.46); however, diabetic patients were significantly older (p = 0.0001). Patients with concomitant DM displayed higher frequency of the classic clinical presentations of PTB and were 1.8 times more likely to have cavitary lesions on imaging studies (p = 0.012). Furthermore, diabetic patients showed higher initial sputum acid-fast bacillus (AFB) smear grade (p = 0.0001) and were more prone to have delayed culture conversion as compared to their non-diabetic counterparts (77.55 ± 37.74 versus 54.95 ± 27.67 days, respectively; p = 0.0001) which points out to less favorable treatment outcome.

Conclusion

DM showed an impact on different aspects of PTB. Accordingly, integrated bi-directional screening programs for both diseases in the KSA need to be implemented to upgrade health-care services of patients with dual diagnosis.

Host-microbe metatranscriptome reveals differences between acute and chronic infections in diabetes-related foot ulcers

Virtually all diabetes-related foot ulcers (DRFUs) will become colonized by microorganisms that may increase the risk of developing an infection. The reasons why some ulcerations develop acute clinical infections (AI-DRFUs) whilst others develop chronic infection (CI-DRFUs) and the preceding host-microbe interactions in vivo remain largely unknown. Establishing that acute and chronic infections are distinct processes requires demonstrating that these are two different strategies employed by microbes when interacting with a host. In this study, dual-RNA seq was employed to differentiate the host-microbe metatranscriptome between DRFUs that had localized chronic infection or acute clinical infection. Comparison of the host metatranscriptome in AI-DRFUs relative to CI-DRFUs identified upregulated differentially expressed genes (DEGs) that functioned as regulators of vascular lymphatic inflammatory responses, T-cell signalling and olfactory receptors. Conversely, CI-DRFUs upregulated DEGs responsible for cellular homeostasis. Gene set enrichment analysis using Hallmark annotations revealed enrichment of immune and inflammatory profiles in CI-DRFUs relative to AI-DRFUs. Analysis of the microbial metatranscriptome identified the DEGs being enriched within AI-DRFUs relative to CI-DRFUs included several toxins, two-component systems, bacterial motility, secretion systems and genes encoding for energy metabolism. Functions relevant to DRFU pathology were further explored, including biofilm and bacterial pathogenesis. This identified that the expression of biofilm-associated genes was higher within CI-DRFUs compared to that of AI-DRFUs, with mucR being the most highly expressed gene. Collectively, these data provide insights into the host-microbe function in two clinically-distinct infective phenotypes that affect DRFUs. The data reveal that bacteria in acutely infected DRFUs prioritize motility over biofilm and demonstrate greater pathogenicity and mechanisms, which likely subvert host cellular and immune pathways to establish infection. Upregulation of genes for key vascular inflammatory mediators in acutely infected ulcers may contribute, in part, to the clinical picture of a red, hot, swollen foot, which differentiates an acutely infected ulcer from that of a chronic infection.

Anti-diabetics and antimicrobials: Harmony of mutual interplay

Diabetes is one of the four major non-communicable diseases, and appointed by the world health organization as the seventh leading cause of death worldwide. The scientists have turned over every rock in the corners of medical sciences in order to come up with better understanding and hence more effective treatments of diabetes. The continuous research on the subject has elucidated the role of immune disorders and inflammation as definitive factors in the trajectory of diabetes, assuring that blood glucose adjustments would result in a relief in the systemic stress leading to minimizing inflammation. On a parallel basis, microbial infections usually take advantage of immunity disorders and propagate creating a pro-inflammatory environment, all of which can be reversed by antimicrobial treatment. Standing at the crossroads between diabetes, immunity and infection, we aim in this review at projecting the interplay between immunity and diabetes, shedding the light on the overlapping playgrounds for the activity of some antimicrobial and anti-diabetic agents. Furthermore, we focused on the anti-diabetic drugs that can confer antimicrobial or anti-virulence activities.

The impact of the Th17:Treg axis on the IgA-Biome across the glycemic spectrum

Secretory IgA (SIgA) is released into mucosal surfaces where its function extends beyond that of host defense to include the shaping of resident microbial communities by mediating exclusion/inclusion of respective microbes and regulating bacterial gene expression. In this capacity, SIgA acts as the fulcrum on which host immunity and the health of the microbiota are balanced. We recently completed an analysis of the gut and salivary IgA-Biomes (16S rDNA sequencing of SIgA-coated/uncoated bacteria) in Mexican-American adults that identified IgA-Biome differences across the glycemic spectrum. As Th17:Treg ratio imbalances are associated with gut microbiome dysbiosis and chronic inflammatory conditions such as type 2 diabetes, the present study extends our prior work by examining the impact of Th17:Treg ratios (pro-inflammatory:anti-inflammatory T-cell ratios) and the SIgA response (Th17:Treg-SIgA axis) in shaping microbial communities. Examining the impact of Th17:Treg ratios (determined by epigenetic qPCR lymphocyte subset quantification) on the IgA-Biome across diabetes phenotypes identified a proportional relationship between Th17:Treg ratios and alpha diversity in the stool IgA-Biome of those with dysglycemia, significant changes in community composition of the stool and salivary microbiomes across glycemic profiles, and genera preferentially abundant by T-cell inflammatory phenotype. This is the first study to associate epigenetically quantified Th17:Treg ratios with both the larger and SIgA-fractionated microbiome, assess these associations in the context of a chronic inflammatory disease, and offers a novel frame through which to evaluate mucosal microbiomes in the context of host responses and inflammation.

The cumulative dose-dependent effects of metformin on the development of tuberculosis in patients newly diagnosed with type 2 diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is a well-known risk factor for tuberculosis (TB). Metformin, which is an essential anti-diabetic drug, has been shown to exhibit anti-TB effects in patients with DM. Its effect on preventing the development of TB among patients who are newly diagnosed with DM remains unclear.

METHODS

This was a retrospective cohort study using the claims database of the Korean Health Insurance Review and Assessment Service. The study population included patients who were newly diagnosed with type 2 DM and who were treated with anti-diabetic drugs between 1 January 2003 and 31 March 2011. A patient was defined as a metformin user if he/she had taken metformin for more than 28 days within 6 months since cohort entry, and as a metformin non-user if he/she had never been treated with metformin. The development of TB within 2 years after the index date was compared by Cox proportional hazard regression models between metformin users and 1:1 propensity score (PS)-matched non-users.

RESULTS

Among 76,973 patients who were newly diagnosed with type 2 DM, 13,396 were classified as metformin users, 52,736 were classified as metformin non-users, and 10,841 were excluded from the final analysis. PS-matched Cox proportional hazard regression models revealed that metformin use was not associated overall with the prevention of TB development (HR 1.17; 95% CI 0.75-1.83; P = 0.482). There was a trend, however, towards a reduction in the development of TB among patients taking a higher cumulative dose of metformin. Patients who were in the highest quartile (Q4) of cumulative metformin dose had only a 10% risk of developing TB compared to metformin non-users. In contrast, during the early phases of metformin treatment, patients in the second quartile (Q2) of cumulative metformin use had a higher risk of developing TB than patients in the first quartile (Q1).

CONCLUSIONS

Only the highest cumulative doses of metformin were protective against the development of TB among patients who were newly diagnosed with type 2 DM; lower cumulative doses of metformin did not appear to reduce the incidence of active TB infection.

Diabetes mellitus and HIV infection among active tuberculosis patients in Northwest Ethiopia: health facility-based cross-sectional study

Background

The prevalence of diabetes mellitus (DM) is increasing globally and its comorbidity with tuberculosis (TB) is re-emerging, especially in low- and middle-income countries.

Objective

The main aim of this study is to determine the prevalence of DM and HIV infection and their associated risk factors among active tuberculosis patients in Northwest Ethiopia.

Methods

This hospital-based cross-sectional study was conducted between February 1st and June 30th, 2017 among active TB patients in two hospitals of Northwest Ethiopia. Two hundred and sixty-seven active TB cases aged 18 years or older were screened for diabetes using fasting blood glucose (FBG) test. Semi-structured questionnaires were used to collect demographic data, lifestyle habits and clinical data. Identification of pre-diabetes or diabetes in TB patients was achieved according to American Diabetes Association guidelines (2016).

Results

Prevalence of DM and TB comorbidity was 11.5% (95% confidence interval, CI 7.8–15.2) compared to 24.9% (95% CI 20.1–30.1) for pre-diabetes. Prevalence of HIV/TB co-infection was 21.9% (95% CI 16.7–26.8). Risk of DM was higher in TB patients from a rural location (adjusted odds ratio, aOR 3.13, 95% CI 1.02–9.62, p = 0.046). Similarly, DM was higher in TB patients who have a family history of DM (aOR 4.54, 95% CI 1.31–15.68, p = 0.017). Furthermore, HIV/TB co-infection was identified as a predictor of DM comorbidity in active TB patients (aOR 5.11, 95% CI 2.01–12.98, p = 0.001).

Conclusion

The magnitude of DM and pre-diabetes in active TB patients in Northwest Ethiopia was high, warranting collaborative efforts to improve screening and adopt better clinical management strategies for DM–TB comorbid patients. Furthermore, being rural residents, family history of DM and HIV/TB co-infection were found to associate with DM among TB patients, highlighting the importance of the above-mentioned risk factors in the clinical management of this comorbidity.

Obesity-Induced Dysbiosis Exacerbates IFN-γ Production and Pulmonary Inflammation in the Mycobacterium tuberculosis Infection

The microbiota of the gut-lung axis affects local and far-reaching immune responses and might also trigger chronic and inflammatory diseases. We hypothesized that gut dysbiosis induced by obesity, which coexists in countries with a high tuberculosis burden, aggravates the host susceptibility and the pulmonary damage tolerance. To assess our hypothesis, we used a model of high-fat diet (HFD)-induced obesity, followed by infection of C57BL/6 mice with Mycobacterium tuberculosis. We showed that obesity increased the susceptibility, the pulmonary inflammation and IFN-γ levels in M. tuberculosis-infected mice. During the comorbidity obesity and tuberculosis, there is an increase of Bacteroidetes and Firmicutes in the lungs, and an increase of Firmicutes and butyrate in the feces. Depletion of gut microbiota by antibiotic treatment in the obese infected mice reduced the frequencies of CD4+IFN-γ+IL-17- cells and IFN-γ levels in the lungs, associated with an increase of Lactobacillus. Our findings reinforce the role of the gut-lung axis in chronic infections and suggest that the gut microbiota modulation may be a potential host-directed therapy as an adjuvant to treat TB in the context of IFN-γ-mediated immunopathology.

Modulating the foreign body response of implants for diabetes treatment

Diabetes Mellitus is a group of diseases characterized by high blood glucose levels due to patients' inability to produce sufficient insulin. Current interventions often require implants that can detect and correct high blood glucose levels with minimal patient intervention. However, these implantable technologies have not reached their full potential in vivo due to the foreign body response and subsequent development of fibrosis. Therefore, for long-term function of implants, modulating the initial immune response is crucial in preventing the activation and progression of the immune cascade. This review discusses the different molecular mechanisms and cellular interactions involved in the activation and progression of foreign body response (FBR) and fibrosis, specifically for implants used in diabetes. We also highlight the various strategies and techniques that have been used for immunomodulation and prevention of fibrosis. We investigate how these general strategies have been applied to implants used for the treatment of diabetes, offering insights on how these devices can be further modified to circumvent FBR and fibrosis.

The Cox model of predicting mortality among melioidosis patients in Northern Malaysia: A retrospective study

ABSTRACT

Melioidosis is an infectious disease that is initiated by a bacteria recognized as Burkholderia pseudomallei. Despite the high fatality rate from melioidosis, there is a minimal published study about the disease in Malaysia.This study aimed to identify the prognostic factors of mortality among melioidosis patients in northern Malaysia.All inpatient patients who were admitted to Hospital Sultanah Bahiyah, Kedah and Hospital Tuanku Fauziah, Perlis with culture-confirmed melioidosis during the period 2014 to 2017 were included in the study. The study retrospectively collected 510 melioidosis patients from the Melioidosis Registry. Hazard ratio (HR) used in advanced multiple Cox regression was used to obtain the final model of prognostic factors of melioidosis. The analysis was performed using STATA/SE 14.0 for Windows software.From the results, among the admitted patients, 50.1% died at the hospital. The mean age for those who died was 55 years old, and they were mostly male. The most common underlying disease was diabetes mellitus (69.8%), followed by hypertension (32.7%). The majority of cases (86.8%) were bacteremic. The final Cox model identified 5 prognostic factors of mortality among melioidosis patients. The factors were diabetes mellitus, type of melioidosis, platelet count, white blood cell count, and urea value. The results showed that bacteremic melioidosis increased the risk of dying by 3.47 (HR: 3.47, 95% confidence intervals [CI]: 1.67-7.23, P = .001) compared to non-bacteremic melioidosis. Based on the blood investigations, the adjusted HRs from the final model showed that all 3 blood investigations were included as the prognostic factors for the disease (low platelet: HR = 1.76, 95% CI: 1.22-2.54, P = .003; high white blood cell: HR = 1.49, 95% CI 1.06-2.11, P = .023; high urea: HR = 2.92, 95% CI: 1.76-4.85, P < .001; and low level of urea: HR = 2.69, 95% CI: 1.69-4.29, P < .001). By contrast, melioidosis patients with diabetic had 30.0% lower risk of dying from melioidosis compared to those with non-diabetic (HR = 0.70, 95% CI: 0.52-0.94, P = .016).Identifying the prognostic factors of mortality in patients with melioidosis allows a guideline of early management in these patients, which may improve patient's survival.

Anemia, sarcopenia, physical activity, and the risk of tuberculosis in the older population: a nationwide cohort study

Background:

The aim of this study was to investigate whether physical activity, sarcopenia, and anemia are associated an with increased risk of tuberculosis (TB) among the older population.

Methods:

We included 1,245,640 66-year-old subjects who participated in the National Screening Program for Transitional Ages for Koreans from 2009 to 2014. At baseline, we assessed common health problems in the older population, including anemia and sarcopenia. The subjects’ performance in the timed up-and-go (TUG) test was used to predict sarcopenia. The incidence of TB was determined using claims data from the National Health Insurance Service database.

Results:

The median follow-up duration was 6.4 years. There was a significant association between the severity of anemia and TB incidence, with an adjusted hazard ratio (aHR) of 1.28 [95% confidence interval (CI), 1.20–1.36] for mild anemia and 1.69 (95% CI, 1.51–1.88) for moderate to severe anemia. Compared with those who had normal TUG times, participants with slow TUG times (⩾15 s) had a significantly increased risk of TB (aHR 1.19, 95% CI, 1.07–1.33). On the other hand, both irregular (aHR 0.88, 95% CI 0.83–0.93) and regular (aHR 0.84, 95% CI, 0.78–0.92) physical activity reduced the risk of TB. Male sex, lower income, alcohol consumption, smoking, diabetes, and asthma/chronic obstructive pulmonary disease increased the risk of TB.

Conclusion:

The risk of TB among older adults increased with worsening anemia, sarcopenia, and physical inactivity. Physicians should be aware of those modifiable predictors for TB among the older population.

Mycobacterial Growth Inhibition Assay (MGIA) as a Host Directed Diagnostic Tool for the Evaluation of the Immune Response in Subjects Living With Type 2 Diabetes Mellitus

The lack of efficient and cost-effective diagnostic tools contributes to poor control of tuberculosis in endemic countries. Moreover, host biological processes influence susceptibility, and infection resolution. It is well known that comorbidities such as type 2 diabetes mellitus (DM2) affect the host immune response, making individuals more susceptible to Mycobacterium tuberculosis infection. Currently, there are no laboratory tools that can identify those subjects who have a higher risk of developing the disease. In this study, we used a whole blood mycobacterial growth inhibition assay to assess the immune response capacity to inhibit mycobacterial growth between healthy subjects and those living with DM2 with optimal and poor glycemic control. We also measured cytokine levels in the culture supernatant by cytokine bead arrays. We included 89 patients with DM2: 54 patients with optimal control (mean age 56.2 ± 11.75 years) and 35 patients with poor control (mean age 52.05 ± 9.94 years). We also included 44 healthy subjects as controls (mean age 42.12 ± 11.75 years). We compared the Δlog UFC (a value that represents the difference between mycobacterial growth in the control tube versus the subject’s blood) between each group. Our results demonstrate that patients with DM2 had a lower capacity to inhibit M. tuberculosis growth (Δlog UFC DM2 subjects 0.9581 (-0.3897 to 2.495) vs Δlog UFC healthy subjects 0.7190 (-0.2678 to 2.098); p=0.013). Comparing subjects living with DM2 (optimal and poor glycemic control) vs healthy subjects, we found only significant differences between healthy subjects and patients poorly controlled (Δlog UFC optimal control group 0.876 (-0.3897 to 2.495); Δlog UFC poor control group 1.078 (0.068 to 2.33); Δlog UFC healthy subjects 0.7190 (-0.2678 to 2.098); p= 0.022). Therefore, glycemic control assessed by glycosylated hemoglobin values influences the capacity of the host to control the infection. Our results confirm that the whole blood mycobacterial growth inhibition assay has potential utility as an in vitro marker of M. tuberculosis immunological control in vivo in subjects living with DM2. This assay can be used to evaluate the immune response of each individual against M. tuberculosis, allowing clinicians to choose a more specific host-directed therapy.

Covid-19 and diabetes in primary care - How do hematological parameters present in this cohort?

Objectives: Changes in hematological parameters are becoming evident as important early markers of COVID-19. Type 2 Diabetes Mellitus (T2DM) has been shown to be associated with increased severity of COVID-19. In this study, we aim to explore the various hematological variables in COVID-19 positive patients with T2DM, so as to act early and improve patient outcomes.Methods: Medical e-records of seventy adult patients with T2DM who were COVID-19 positive have been analyzed in this retrospective cohort study. Demographic, clinical and laboratory parameters for these patients were examined.Results: Of the seventy patients with T2DM, 48.88% had poorly controlled diabetes. 70.69% were pyrexial, 56.25% were tachycardic and 38.58% were asymptomatic on presentation. Amongst the hematological parameters, anemia was seen in 10% of males and 15.38% of females. 20% had a high red-blood-cell-distribution-width (RDW). 7.27% had thrombocytosis and 3.64% had thrombocytopenia. 73.3% had a high platelet-distribution-width (PDW) and 44.44% had an increased mean-platelet-volume (MPV). 16.36% were neutropenic and 16.67% had lymphocytopenia.Conclusion: Diabetic COVID-19 positive patients have been shown to have prominent manifestations of the hemopoietic-system with varied hematological profiles. Recognizing the implications of these variables early in primary-care, can help clinicians aid management decisions and dictate early referral to secondary-care services, to help improve prognosis.

Diabetes is associated with higher mortality and severity in hospitalized patients with COVID-19

As a novel cause of pneumonia, coronavirus disease 2019 (COVID-19) has rapidly progressed worldwide. Previous studies have indicated COVID-19 patients with diabetes show higher mortality rates and more severe COVID-19 infection with an increased requirement for intensive care and hospital length of stay (LOS) compared to non-diabetic patients. The present study aimed to investigate the association of diabetes and COVID-19 outcome with severity of disease in hospitalized patients. The present case-control study included 268 patients diagnosed with COVID-19 who were hospitalized in Ayatollah Khoyi Hospital, Khoy, Iran. Diabetes was identified based on medical history and/or criteria of published documents. Out of 268 patients (median age of 59 years; 53.4 % male), 127 patients had diabetes (47 %). Diabetic patients had remarkably higher mortality rates (adjusted odds ratio, aOR: 3.36; confidence interval, CI: 1.17-9.66), requirement for invasive mechanical ventilation (IMV) (aOR: 4.59; CI: 1.38-15.25), and LOS (aOR: 1.13; CI: 1.06-1.24) compared to patients without diabetes. Inflammatory biomarkers including C-reactive protein (CRP), lactate dehydrogenase (LDH), and erythrocyte sedimentation rate (ESR) were increased in patients with diabetes compared to non-diabetic patients (P < 0.05 for all the comparisons). In hospitalized patients with COVID-19, diabetes was correlated with increased disease severity and mortality.

Comorbid illnesses are associated with altered adaptive immune responses to SARS-CoV-2

Comorbid medical illnesses, such as obesity and diabetes, are associated with more severe COVID-19, hospitalization, and death. However, the role of the immune system in mediating these clinical outcomes has not been determined. We used multiparameter flow cytometry and systems serology to comprehensively profile the functions of T cells and antibodies targeting spike, nucleocapsid, and envelope proteins in a convalescent cohort of COVID-19 subjects who were either hospitalized (n = 20) or not hospitalized (n = 40). To avoid confounding, subjects were matched by age, sex, ethnicity, and date of symptom onset. Surprisingly, we found that the magnitude and functional breadth of virus-specific CD4⁺ T cell and antibody responses were consistently higher among hospitalized subjects, particularly those with medical comorbidities. However, an integrated analysis identified more coordination between polyfunctional CD4⁺ T cells and antibodies targeting the S1 domain of spike among subjects who were not hospitalized. These data reveal a functionally diverse and coordinated response between T cells and antibodies targeting SARS-CoV-2, which is reduced in the presence of comorbid illnesses that are known risk factors for severe COVID-19.

Risk factors associated with the progression of COVID-19 in elderly diabetes patients

AIM

To describe the clinical characteristics and risk factors associated with the progression of COVID-19 in elderly diabetes patients.

METHODS

This was a retrospective cohort study, including elderly COVID-19 patients admitted to Wuhan Huoshenshan Hospital between February 10 and 13, 2020. Demographic data, medical history, signs and symptoms, and laboratory parameters were collected and analysed.

RESULTS

We included 131 elderly COVID-19 patients (50 patients with diabetes). COVID-19 diabetes patients experienced more severe pneumonia and abnormal organ functions than non-diabetes patients (P < 0.05 or P < 0.01). Most function indicators were significantly different between the mild to moderate and severely ill groups in diabetes patients (P < 0.05 or P < 0.01). Python analysis confirmed diabetes was the independent risk factor of COVID-19 progression in elderly patients. All blood glucose (BG) indices went into the risk factor equation. The cut-off values of COVID-19 progression were BG value on admission > 8.0 mmol/L or maximum BG value > 12.0 mmol/L in all elderly patients, and BG value on admission > 5.1 mmol/L or maximum BG value > 5.4 mmol/L in non-diabetes patients.

CONCLUSIONS

Diabetes is an independent important risk factor, and glucose levels associate closely with COVID-19 progression in elderly patients.

Diabetes Modifies the Clinic Presentation of Cutaneous Leishmaniasis

BACKGROUND

Cutaneous leishmaniasis (CL) caused by L. braziliensis is characterized by 1 or multiple well-limited ulcerated lesions. Diabetes mellitus (DM) impairs neutrophil and monocyte function, and there is a report of vegetative lesions in a patient with both diseases in Morocco. Here we evaluate the influence of DM on clinical manifestations, immune response, and in the treatment of CL.

METHODS

The participants were 36 DM patients with CL and 36 patients with CL without DM, matched by age and gender. The diagnosis of CL was performed by documentation of DNA of L. braziliensis by polymerase chain reaction in the lesion biopsy and histopathologic findings. All patients were treated with Glucantime (Sanofi-Aventis) 20 mg/kg of weight per day for 20 days.

RESULTS

There was no difference in the majority of the clinical variables between the groups, and the cure rate in patients with CL and DM (67%) was similar to that observed in CL patients (56%; P ˃ .05). The most important finding was the documentation that 36% of the patients with DM and CL had atypical cutaneous lesions characterized by large superficial ulcers without defined borders. High levels of interferon-γ, tumor necrosis facor, and interleukin-1β were detected in the supernatants of mononuclear cells stimulated with Leishmania antigen in patients with DM and atypical CL. Moreover, while cure was observed in only 33% of the patients with DM and atypical CL lesions, it was observed in 85% of patients with typical lesions (P < .05).

CONCLUSIONS

DM modifies the clinical presentation of CL, enhances pro-inflammatory cytokine production, and impairs response to antimony therapy.

T cell and antibody functional correlates of severe COVID-19

Comorbid medical illnesses, such as obesity and diabetes, are associated with more severe COVID-19, hospitalization, and death. However, the role of the immune system in mediating these clinical outcomes has not been determined. We used multi-parameter flow cytometry and systems serology to comprehensively profile the functions of T cells and antibodies targeting spike, nucleocapsid, and envelope proteins in a convalescent cohort of COVID-19 subjects who were either hospitalized (n=20) or not hospitalized (n=40). To avoid confounding, subjects were matched by age, sex, ethnicity, and date of symptom onset. Surprisingly, we found that the magnitude and functional breadth of virus-specific CD4 T cell and antibody responses were consistently higher among hospitalized subjects, particularly those with medical comorbidities. However, an integrated analysis identified more coordination between polyfunctional CD4 T-cells and antibodies targeting the S1 domain of spike among subjects that were not hospitalized. These data reveal a functionally diverse and coordinated response between T cells and antibodies targeting SARS-CoV-2 which is reduced in the presence of comorbid illnesses that are known risk factors for severe COVID-19. Our data suggest that isolated measurements of the magnitudes of spike-specific immune responses are likely insufficient to anticipate vaccine efficacy in high-risk populations.

Impact of Diabetes on the Gut and Salivary IgA Microbiomes

Mucosal surfaces like those present in the lung, gut, and mouth interface with distinct external environments. These mucosal gateways are not only portals of entry for potential pathogens but also homes to microbial communities that impact host health. Secretory immunoglobulin A (SIgA) is the single most abundant acquired immune component secreted onto mucosal surfaces and, via the process of immune exclusion, shapes the architecture of these microbiomes. Not all microorganisms at mucosal surfaces are targeted by SIgA; therefore, a better understanding of the SIgA-coated fraction may identify the microbial constituents that stimulate host immune responses in the context of health and disease. Chronic diseases like type 2 diabetes are associated with altered microbial communities (dysbiosis) that in turn affect immune-mediated homeostasis. 16S rRNA gene sequencing of SIgA-coated/uncoated bacteria (IgA-Biome) was conducted on stool and saliva samples of normoglycemic participants and individuals with prediabetes or diabetes (n = 8/group). These analyses demonstrated shifts in relative abundance in the IgA-Biome profiles between normoglycemic, prediabetic, or diabetic samples distinct from that of the overall microbiome. Differences in IgA-Biome alpha diversity were apparent for both stool and saliva, while overarching bacterial community differences (beta diversity) were also observed in saliva. These data suggest that IgA-Biome analyses can be used to identify novel microbial signatures associated with diabetes and support the need for further studies exploring these communities. Ultimately, an understanding of the IgA-Biome may promote the development of novel strategies to restructure the microbiome as a means of preventing or treating diseases associated with dysbiosis at mucosal surfaces.

Mechanism of higher risk for COVID-19 in diabetes: a mask to lift

PURPOSE

This essay aims to propose suggestions on what we can learn from previous investigations to conduct further studies on the potential mechanisms underlying the effect of diabetes mellitus on COVID-19.

METHODS

We reviewed some literature on diabetes and other types of coronavirus infection such as Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS) and made some summaries and comparisons.

RESULTS

Diabetes affect the occurrence and progression of COVID-19.

CONCLUSIONS

In-depth and comprehensive exploration of the mechanism of diabetes affecting COVID-19 should be carried out.

Of tuberculosis and non-tuberculous mycobacterial infections - a comparative analysis of epidemiology, diagnosis and treatment

Pulmonary diseases due to mycobacteria cause significant morbidity and mortality to human health. In addition to tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), recent epidemiological studies have shown the emergence of non-tuberculous mycobacteria (NTM) species in causing lung diseases in humans. Although more than 170 NTM species are present in various environmental niches, only a handful, primarily Mycobacterium avium complex and M. abscessus, have been implicated in pulmonary disease. While TB is transmitted through inhalation of aerosol droplets containing Mtb, generated by patients with symptomatic disease, NTM disease is mostly disseminated through aerosols originated from the environment. However, following inhalation, both Mtb and NTM are phagocytosed by alveolar macrophages in the lungs. Subsequently, various immune cells are recruited from the circulation to the site of infection, which leads to granuloma formation. Although the pathophysiology of TB and NTM diseases share several fundamental cellular and molecular events, the host-susceptibility to Mtb and NTM infections are different. Striking differences also exist in the disease presentation between TB and NTM cases. While NTM disease is primarily associated with bronchiectasis, this condition is rarely a predisposing factor for TB. Similarly, in Human Immunodeficiency Virus (HIV)-infected individuals, NTM disease presents as disseminated, extrapulmonary form rather than as a miliary, pulmonary disease, which is seen in Mtb infection. The diagnostic modalities for TB, including molecular diagnosis and drug-susceptibility testing (DST), are more advanced and possess a higher rate of sensitivity and specificity, compared to the tools available for NTM infections. In general, drug-sensitive TB is effectively treated with a standard multi-drug regimen containing well-defined first- and second-line antibiotics. However, the treatment of drug-resistant TB requires the additional, newer class of antibiotics in combination with or without the first and second-line drugs. In contrast, the NTM species display significant heterogeneity in their susceptibility to standard anti-TB drugs. Thus, the treatment for NTM diseases usually involves the use of macrolides and injectable aminoglycosides. Although well-established international guidelines are available, treatment of NTM disease is mostly empirical and not entirely successful. In general, the treatment duration is much longer for NTM diseases, compared to TB, and resection surgery of affected organ(s) is part of treatment for patients with NTM diseases that do not respond to the antibiotics treatment. Here, we discuss the epidemiology, diagnosis, and treatment modalities available for TB and NTM diseases of humans.

Association of Blood Glucose Control and Outcomes in Patients with COVID-19 and Pre-existing Type 2 Diabetes

Type 2 diabetes (T2D) is a major comorbidity of COVID-19. However, the impact of blood glucose (BG) control on the degree of required medical interventions and on mortality in patients with COVID-19 and T2D remains uncertain. Thus, we performed a retrospective, multi-centered study of 7,337 cases of COVID-19 in Hubei Province, China, among which 952 had pre-existing T2D. We found that subjects with T2D required more medical interventions and had a significantly higher mortality (7.8% versus 2.7%; adjusted hazard ratio [HR], 1.49) and multiple organ injury than the non-diabetic individuals. Further, we found that well-controlled BG (glycemic variability within 3.9 to 10.0 mmol/L) was associated with markedly lower mortality compared to individuals with poorly controlled BG (upper limit of glycemic variability exceeding 10.0 mmol/L) (adjusted HR, 0.14) during hospitalization. These findings provide clinical evidence correlating improved glycemic control with better outcomes in patients with COVID-19 and pre-existing T2D.

Changes in T-lymphocyte subsets and risk factors in human immunodeficiency virus-negative patients with active tuberculosis

Purpose

Immune function imbalance is closely associated with the occurrence and development of infectious diseases. We studied the characteristics of changes in T-lymphocyte subsets and their risk factors in HIV-negative patients with active tuberculosis (ATB).

Methods

T-lymphocyte subsets in 275 HIV-negative ATB patients were quantitatively analyzed and compared with an Mycobacteriumtuberculosis-free control group. Single-factor and multifactor analyses of clinical and laboratory characteristics of patients were also conducted.

Results

In ATB patients, CD4 and CD8 T-cell counts decreased, and the levels were positively interrelated (r = 0.655, P < 0.0001). After 4 weeks of antituberculosis treatment, CD4 and CD8 T-cell counts increased significantly but remained lower than in the control group. CD4 and CD8 cell counts were negatively associated with the extent of lesions detected in the chest by computed tomography (all P < 0.05). Although not reflected in the CD4/CD8 ratio, CD4 and CD8 cell counts differed between drug-resistant TB patients and drug-susceptible TB patients (P = 0.030). The multivariate analysis showed prealbumin, alpha-1 globulin, body mass index, and platelet count were independent risk factors for decreased CD4 cell count (all P < 0.05), while age and platelet count were independent risk factors for decreased CD8 cell count (all P < 0.05).

Conclusion

CD4 and CD8 T-cell counts showed the evident value in predicting ATB severity. An increase in the CD4/CD8 ratio may be a critical clue of drug resistance in ATB. Although the factors influencing CD4 and CD8 are not identical, our results indicated the importance of serum protein and platelets to ATB patients’ immune function.

Electronic supplementary material

The online version of this article (10.1007/s15010-020-01451-2) contains supplementary material, which is available to authorized users.

Determinants of multidrug-resistant tuberculosis in São Paulo-Brazil: a multilevel Bayesian analysis of factors associated with individual, community and access to health services

Objective

Multidrug‐resistant tuberculosis (MDR‐TB) remains a serious public health problem worldwide. Accordingly, this study sought to identify individual, community and access to health services risk factors for MDR‐TB.

Methods

Retrospective cohort of all TB cases diagnosed between 2006 and 2016 in the state of São Paulo. A Bayesian spatial hierarchical analysis with a multilevel design was carried out.

Results

It was identified that the history of previous TB treatment (Odds Ratios [OR]:13.86, 95% credibility interval [95% CI]:12.06–15.93), positive sputum culture test (OR: 5.26, 95% CI: 4.44–6.23), diabetes mellitus (OR: 2.34, 95% CI: 1.87–2.91), residing at a standard address (OR: 2.62, 95% CI: 1.91–3.60), positive sputum smear microscopy (OR: 1.74, 95% CI: 1.44–2.12), cavitary pulmonary TB (OR: 1.35, 95% CI: 1.14–1.60) and diagnosis performed due to spontaneous request (OR: 1.26; 95% CI: 1.10–1.46) were associated with MDR‐TB. Furthermore, municipalities that performed HIV tests in less than 42.65% of patients with TB (OR: 1.50, 95% CI: 1.25–1.79), that diagnosed TB cases only after death (OR: 1.50, 95% CI: 1.17–1.93) and that had more than 20.16% of their population with income between ¼ and ½ of one minimum wage (OR: 1.56, 95% CI: 1.30–1.87) were also related to the MDR‐TB.

Conclusions

Knowledge of these predictive factors may help to develop more comprehensive disease prevention strategies for MDR‐TB, avoiding the risks expressed regarding drug resistance expansion.

α-Glucosidase Inhibitor Can Effectively Inhibit the Risk of Tuberculosis in Patients with Diabetes: A Nested Case-Control Study

Diabetes mellitus (DM) and tuberculosis (TB) are major public health and economic burdens. DM increases Mycobacterium tuberculosis (M.tb) infection rates and treatment durations. This study evaluated the relationship between five classes of oral DM medications and TB infection risk in DM patients. We used longitudinal records from the Taiwan Longitudinal Health Insurance Research Database. DM patients were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 250 and A code A181. TB patients were identified using ICD-9-CM code 010.x-017.x. Oral DM medications were divided into five classes: sulfonylureas, biguanides, meglitinides, α-glucosidase inhibitors (AGIs), and thiazolidinediones. Users were classified as nonusers, low-concentration users, and high-concentration users. The incidence rate ratio (IRR) was derived using multivariate Poisson regression to calculate the relative risk of TB infection. DM patients using low- and high-concentration AGIs had significantly lower TB infection risks compared with nonusers. The IRRs of the sulfonylureas and AGI users were [CI] 0.693-0.948) and (95% CI 0.651-0.995), respectively. The other four classes of medications exhibited no significant effect on TB infection risk in DM patients. Furthermore, DM patients using high-concentration AGIs had a significantly lower TB infection risk compared with those using low-concentration AGIs (IRR 0.918, 95% CI: 0.854-0.987). We noted a dose-response relationship in the effects of DM medications on TB risk. Accordingly, we suggest that DM patients use AGIs to benefit from their protective effect on TB infection risk.

New Concepts in Tuberculosis Host Defense

Tuberculosis (TB) host defense depends on cellular immunity, including macrophages and adaptively acquired CD4⁺ and CD8⁺ T cells. More recently, roles for new immune components, including neutrophils, innate T cells, and B cells, have been defined, and the understanding of the function of macrophages and adaptively acquired T cells has been advanced. Moreover, the understanding of TB immunology elucidates TB infection and disease as a spectrum. Finally, determinates of TB host defense, such as age and comorbidities, affect clinical expression of TB disease. Herein, the authors comprehensively review TB immunology with an emphasis on new advances.

Adults with Mycobacterium tuberculosis infection and pre-diabetes have increased levels of QuantiFERON interferon-gamma responses

BACKGROUND

Diabetes is associated with increased prevalence of TB infection in the US. We assessed associations between diabetes and interferon-gamma (IFN-γ) TB antigen response among adults with TB infection using US representative data.

METHODS

National Health and Nutrition Examination (NHANES) participants >19 years from 2011 to 2012 with positive QuantiFERON®-TB Gold-In-Tube (QFT) results were eligible. Diabetes was defined by combination of self-report and glycated hemoglobin (HbA1c). Quantitative IFN-γ TB antigen was classified as high (≥10 IU/mL), intermediate (1.01-9.99 IU/mL), or low (0.35-1.00 IU/mL). Analyses accounted for NHANES weighted design.

RESULTS

Among NHANES participants >19 years, n = 513 had positive QFT (5.9%). Among those with positive QFT, diabetes prevalence was 22.2% and pre-diabetes was 25.9%. Overall, 16.7% of positive QFT participants had high IFN-γ TB antigen levels including 21.7% among those with diabetes, 20.8% among those with pre-diabetes, and 12.6% among euglycemic participants. In adjusted analyses, high IFN-γ TB antigen response was more common among those with pre-diabetes (aOR 1.9, 95%CI 1.0, 3.6) compared to euglycemic participants.

CONCLUSION

Higher antigen responses may reflect immunopathy consistent with an exaggerated inflammatory but ineffectual response to TB or a reflection of more Mtb replication in participants with pre-diabetes or diabetes.

Poor Vitamin D Status in Active Pulmonary Tuberculosis Patients and Its Correlation with Leptin and TNF-α

Vitamin D deficiency (VDD) is common in tuberculosis (TB) and may be implicated in the etiology of the disease and in its clinical course. The aim of this study was to investigate the association between leptin, inflammatory markers and VD status in TB patients, stratified for presence or absence of diabetes mellitus (DM). Two hundred ninety-nine TB patients were recruited from October 2015 to August 2016. Also, 91 normal controls were included. The information including socio-demographics, dietary intake and living habits was obtained by face-to-face interview. Serum concentrations of leptin and TNF-α, CRP and IL-6 were compared between TB patients with and without severe VDD (SVDD). Pearson's correlation was used to analyze the association between TNF-α, leptin and 25-hydroxyvitamin D (25(OH)D). A significantly higher prevalence of VDD and SVDD was observed in TB patients compared with normal controls (93.0% vs 70.3%, 65.9% vs 3.3% respectively). Concentration of leptin was significantly lower, while TNF-α higher in TB patients with SVDD compared to those without (p<0.05). After adjustment for confounders, leptin was positively associated with 25(OH)D (r=0.210, p=0.002) with similar correlation in TB patients with DM (r=0.240, p=0.020). A negative association between TNF-α and 25(OH)D was observed (r=-0.197, p=0.003), which was significant only in the subgroup without DM (r=-0.304, p=0.001). Our findings indicate that a higher VD status in TB patients may be related to higher immune activity and less serious tissue damage, and that this relation is different according to presence or absence of DM co-morbidity.

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.

BCG and BCGΔBCG1419c protect type 2 diabetic mice against tuberculosis via different participation of T and B lymphocytes, dendritic cells and pro-inflammatory cytokines

Comorbidity between Tuberculosis (TB) and type 2 diabetes (T2D) is one of the greatest contributors to the spread of Mycobacterium tuberculosis (M. tuberculosis) in low- and middle-income countries. T2D compromises key steps of immune responses against M. tuberculosis and it might affect the protection afforded by vaccine candidates against TB. We compared the protection and immune response afforded by the BCGΔBCG1419c vaccine candidate versus that of wild-type BCG in mice with T2D. Vaccination with both BCGΔBCG1419c, BCG or infection with M. tuberculosis reduced weight loss, hyperglycemia, and insulin resistance during T2D progression, suggesting that metabolic changes affecting these parameters were affected by mycobacteria. For control of acute TB, and compared with non-vaccinated controls, BCG showed a dominant T CD4⁺ response whereas BCGΔBCG1419c showed a dominant T CD8⁺/B lymphocyte response. Moreover, BCG maintained an increased response in lung cells via IFN-γ, TNF-α, and IL-4, while BCGΔBCG1419c increased IFN-γ but reduced IL-4 production. As for chronic TB, and compared with non-vaccinated controls, both BCG strains had a predominant presence of T CD4⁺ lymphocytes. In counterpart, BCGΔBCG1419c led to increased presence of dendritic cells and an increased production of IL-1 β. Overall, while BCG effectively reduced pneumonia in acute infection, it failed to reduce it in chronic infection, whereas we hypothesize that increased production of IL-1 β induced by BCGΔBCG1419c contributed to reduced pneumonia and alveolitis in chronic TB. Our results show that BCG and BCGΔBCG1419c protect T2D mice against TB via different participation of T and B lymphocytes, dendritic cells, and pro-inflammatory cytokines.

Drug resistance of previously treated tuberculosis patients with diabetes mellitus in Shandong, China

BACKGROUND

Although the association between diabetes mellitus (DM) and tuberculosis (TB) has been well-documented for centuries, evidence of the link between diabetes and drug resistance among previously treated TB patients remains limited and inconsistent.

METHODS

An observational study was performed that involved 1791 retreated TB-no DM patients (refers to TB cases without diabetes) and 93 retreated TB-DM patients (refers to TB cases with diabetes) in Shandong, China from 2004 to 2017. Baseline data including demographic and clinical characteristics, drug susceptibility test (DST) results, and diabetes status were collected. Categorical baseline characteristics were compared by Fisher's exact or Pearson Chi-square test. Univariable analysis and multivariable logistic models were used to estimate the association between diabetes and different drug resistance profiles.

RESULTS

Retreated TB-DM patients have a higher rate of drug resistance than TB-no DM patients (34.41% vs 25.00%, P < 0.01). Diabetes co-morbidity was significantly associated with any drug-resistant tuberculosis (DR-TB, odds ratio (OR):1.56, 95% confidence interval (CI): 1.01-2.43), multidrug resistant tuberculosis (MDR-TB, OR: 2.48, 95%CI:1.39-4.41; adjusted OR (aOR):2.94, 95%CI:1.57-5.48), isoniazid-related resistance (OR:1.71, 95%CI:1.04-2.81), rifampin-related resistance (OR:2.56, 0.54, 95%CI: 1.54-4.26; aOR:2.69, 95%CI:1.524-4.74), isoniazid + rifampin resistance (OR: 3.55, 95%CI:1.33-9.44; aOR:4.13, 95%CI:1.46-11.66), any resistance to isoniazid + streptomycin (OR:2.34, 95%CI:1.41-3.89; aOR:2.22, 95%CI:1.26-3.94), and any resistance to rifampin + isoniazid (OR:2.48, 95%CI:1.39-4.41; aOR:2.94, 95%CI: 1.57-5.48), compared with pan susceptible TB cases, P < 0.05.

CONCLUSIONS

The risk of acquired drug resistance increased significantly among retreated TB-DM patients compared with retreated TB-no DM patients, underlining the necessity of more interventions during the clinical management of TB-DM cases.

Enhanced Mycobacterial Antigen-Induced Pro-Inflammatory Cytokine Production in Lymph Node Tuberculosis

Lymph node tuberculosis (LNTB) is characterized by the enhanced baseline and antigen-specific production of type 1/17 cytokines and reduced baseline and antigen-specific production of interleukin (IL)-1β and IL-18 at the site of infection when compared with peripheral blood. However, the cytokine profile in the lymph nodes (LNs) of Mycobacterium tuberculosis culture-positive LNTB (LNTB+) and negative LNTB (LNTB-) has not been examined. To address this, we have examined the baseline and mycobacterial antigen-stimulated cytokine levels of type 1 (interferon gamma [IFNγ], tumor necrosis factor alpha [TNFα], IL-2), type 2 (IL-4, IL-5, and IL-13), type 17 (IL-17A, IL-17F, and IL-22), pro-inflammatory (IL-1α, IL-1β, IL-18, and granulocyte macrophage colony-stimulating factor [GM-CSF]), and regulatory cytokines (IL-10, transforming growth factor beta [TGF-β]) cytokines in the LN culture supernatants of LNTB+ and LNTB- individuals. We have observed significantly enhanced baseline levels of IL-13 and IL-10 and significantly reduced baseline levels of IL-4 and GM-CSF in LNTB+ individuals compared with LNTB- individuals. By contrast, we have observed significantly enhanced levels of type 1 (IFNγ, TNFα, and IL-2), type 17 (IL-17F and IL-22), and pro-inflammatory (IL-1α and GM-CSF) cytokines and significantly reduced levels of TGFβ in response to purified protein derivative, early secreted antigen-6, and culture filtrate protein-10 antigens in LNTB+ compared with LNTB- individuals. On phorbol 12-myristate 13-acetate/ionomycin stimulation, no significant difference was observed for any of the cytokines examined. Thus, our study revealed several interesting differences in the cytokine profiles of mycobacterial antigen-stimulated LN cultures in LNTB+ and LNTB- individuals. Therefore, we suggest the presence of mycobacteria plays a significant role in driving the cytokine response at the site of infection in LNTB.

Screening for pulmonary tuberculosis in high-risk groups of diabetic patients

BACKGROUND

The double burden of diabetes mellitus (DM) and tuberculosis (TB) has attracted increasing attention, because DM not only increases the risk of active TB but also affects treatment outcomes. Screening for TB among diabetic patients has been recommended, but requires real-world evidence by considering its cost-effectiveness, cost-utility ratio, and cost-benefit ratio.

METHODS

A screening program was conducted in Jiangyin City of Jiangsu Province, China. A total of 14 869 diabetic patients received regular physical examinations for three consecutive years and were followed for the diagnosis of TB. The cost of screening and the effectiveness, utility, and social benefits attributed to the program were evaluated. In addition, a matched case-control study was conducted and the nomogram was used to identify high-risk groups that could be the target population for screening.

RESULTS

Among the 14 869 diabetic patients who participated in this screening program, 22 were diagnosed with TB, resulting in an incremental cost-effectiveness ratio (ICER) of 83 910 CNY per disability-adjusted life-year (DALY) gained and a cost-benefit ratio of 0.50. If the screening program was limited to high-risk diabetic patients by considering body mass index (BMI), fasting blood glucose (FBG), and triglycerides, the ICER decreased to 34 303 CNY per DALY gained and the cost-benefit ratio increased to 1.22.

CONCLUSIONS

Screening for TB using regular chest X-ray examinations is feasible but not economical in areas with a low incidence of TB. It is recommended that diabetic patients with a low BMI, high FBG, and low triglycerides are selected as subjects for TB screening.

In silico transcriptional analysis of mRNA and miRNA reveals unique biosignatures that characterizes different types of diabetes

Diabetes (DM) has a significant impact on public health. We performed an in silico study of paired datasets of messenger RNA (mRNA) micro-RNA (miRNA) transcripts to delineate potential biosignatures that could distinguish prediabetes (pre-DM), type-1DM (T1DM) and type-2DM (T2DM). Two publicly available datasets containing expression values of mRNA and miRNA obtained from individuals diagnosed with pre-DM, T1DM or T2DM, and normoglycemic controls (NC), were analyzed using systems biology approaches to define combined signatures to distinguish different clinical groups. The mRNA profile of both pre-DM and T2DM was hallmarked by several differentially expressed genes (DEGs) compared to NC. Nevertheless, T1DM was characterized by an overall low number of DEGs. The miRNA signature profiles were composed of a substantially lower number of differentially expressed targets. Gene enrichment analysis revealed several inflammatory pathways in T2DM and fewer in pre-DM, but with shared findings such as Tuberculosis. The integration of mRNA and miRNA datasets improved the identification and discriminated the group composed by pre-DM and T2DM patients from that constituted by normoglycemic and T1DM individuals. The integrated transcriptomic analysis of mRNA and miRNA expression revealed a unique biosignature able to characterize different types of DM.

Diabetes Mellitus and Tuberculosis Comorbidity and Associated Factors Among Bale Zone Health Institutions, Southeast Ethiopia

BACKGROUND

Globally, tuberculosis and diabetes mellitus co-morbidity is higher than tuberculosis and human immunodeficiency virus comorbidity. Considering this, the World Health Organization and the International Union against tuberculosis and lung disease recommend bi-directional screening of the two diseases. However, in Ethiopia, bi-directional screening has not been started yet.

OBJECTIVE

The objective of this study was to assess the prevalence of diabetes mellitus and tuberculosis comorbidity and its predictors among adult tuberculosis patients in Bale Zone Health Institutions, Southeastern Ethiopia.

MATERIALS AND METHODS

Institutional-based cross-sectional study carried out using interviewer administered questionnaire, registration review, anthropometric and blood glucose level measurement from March, 30, 2019 to April, 30, 2019. Three hundred twenty-one tuberculosis patients were selected from tuberculosis registration log book using lottery methods. The collected data were checked for completeness, coded and entered in to EpiData3.0.2 and exported to SPSS version 20. Independent variables that had p value less 0.25 were used as candidates for multiple logistic regressions to control confounders. Variables that had significant association were identified by calculating odds ratio, with 95% confidence interval, and p value less than 0.05 used to declare statistical significance.

RESULTS

Diabetes mellitus and tuberculosis comorbidity among adult tuberculosis patients was 5.1% (95% CI: 2.7%, 7.5%). Age with ≥50 years (AOR=3.98, 95% CI: 1.13, 14.36), having extra pulmonary tuberculosis (AOR=3.31, 95% CI: 1.16, 9.44) and being females (AOR=3.8, 95% CI: 1.17, 12.33) were significantly associated with the comorbidity of the two diseases.

CONCLUSION AND RECOMMENDATION

The prevalence of diabetes mellitus and tuberculosis comorbidity was high. Female tuberculosis patients, tuberculosis patients with age ≥50 years and those having extra pulmonary tuberculosis patients should be screened for diabetes mellitus.

The Effects of Obesity on Outcome in Preclinical Animal Models of Infection and Sepsis: A Systematic Review and Meta-Analysis

BACKGROUND

Clinical studies suggest obesity paradoxically increases survival during bacterial infection and sepsis but decreases it with influenza, but these studies are observational. By contrast, animal studies of obesity in infection can prospectively compare obese versus nonobese controls. We performed a systematic review and meta-analysis of animal investigations to further examine obesity's survival effect in infection and sepsis.

METHODS

Databases were searched for studies comparing survival in obese versus nonobese controls. We performed a systematic review and meta-analysis of animal investigations to further examine obesity's survival effect in infection and sepsis. Methods. Databases were searched for studies comparing survival in obese versus nonobese animals following bacteria, lipopolysaccharide, or influenza virus challenges.

RESULTS

Twenty-one studies (761 obese and 603 control animals) met the inclusion criteria. Obesity reduced survival in 19 studies (11 significantly) and the odds ratio (95% CI) of survival (0.21(0.13, 0.35); I ² = 64%, p < 0.01p < 0.01p < 0.01) but with high heterogeneity. Obesity reduced survival (1) consistently in both single-strain bacteria- and lipopolysaccharide-challenged studies (n = 6 studies, 0.21(0.13, 0.34); I ² = 64%, p < 0.01p < 0.01) but with high heterogeneity. Obesity reduced survival (1) consistently in both single-strain bacteria- and lipopolysaccharide-challenged studies (n = 6 studies, 0.21(0.13, 0.34); I ² = 64%, p < 0.01p < 0.01) but with high heterogeneity. Obesity reduced survival (1) consistently in both single-strain bacteria- and lipopolysaccharide-challenged studies (n = 6 studies, 0.21(0.13, 0.34); I ² = 64%, p < 0.01p < 0.01) but with high heterogeneity. Obesity reduced survival (1) consistently in both single-strain bacteria- and lipopolysaccharide-challenged studies (n = 6 studies, 0.21(0.13, 0.34); I ² = 64%, p < 0.01p < 0.01p < 0.01) but with high heterogeneity. Obesity reduced survival (1) consistently in both single-strain bacteria- and lipopolysaccharide-challenged studies (n = 6 studies, 0.21(0.13, 0.34); I ² = 31%, p=0.20 and n = 5, 0.22(0.13, 0.36); I ² = 0%, p=0.59, respectively), (2) not significantly with cecal ligation and puncture (n = 4, 0.72(0.08, 6.23); I ² = 75%, p < 0.01), and (3) significantly with influenza but with high heterogeneity (n = 6, 0.12(0.04, 0.34); I ² = 73%, p < 0.01). Obesity's survival effects did not differ significantly comparing the four challenge types (p=0.49). Animal models did not include antimicrobials or glycemic control and study quality was low.

CONCLUSIONS

Preclinical and clinical studies together emphasize the need for prospective studies in patients accurately assessing obesity's impact on survival during severe infection.

An Inflammatory Story: Antibodies in Tuberculosis Comorbidities

Mycobacterium tuberculosis (Mtb) resides in a quarter of the world's population and is the causative agent for tuberculosis (TB), the most common infectious reason of death in humans today. Although cellular immunity has been firmly established in the control of Mtb, there is growing evidence that antibodies may also modulate the infection. More specifically, certain antibody features are associated with inflammation and are divergent in different states of human infection and disease. Importantly, TB impacts not just the healthy but also those with chronic conditions. While HIV represents the quintessential comorbid condition for TB, recent epidemiological evidence shows that additional chronic conditions such as diabetes and kidney disease are rising. In fact, the prevalence of diabetes as a comorbid TB condition is now higher than that of HIV. These chronic diseases are themselves independently associated with pro-inflammatory immune states that encompass antibody profiles. This review discusses isotypes, subclasses, post-translational modifications and Fc-mediated functions of antibodies in TB infection and in the comorbid chronic conditions of HIV, diabetes, and kidney diseases. We propose that inflammatory antibody profiles, which are a marker of active TB, may be an important biomarker for detection of TB disease progression within comorbid individuals. We highlight the need for future studies to determine which inflammatory antibody profiles are the consequences of comorbidities and which may potentially contribute to TB reactivation.

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.

Impacts of metformin on tuberculosis incidence and clinical outcomes in patients with diabetes: a systematic review and meta-analysis

BACKGROUND

Accumulating evidence suggested that the use of metformin had more benefits for both prevention and treatment of tuberculosis (TB) than non-metformin use in patients with diabetes mellitus (DM); however, it remains to be fully elucidated on this topic. Thus, we conducted a systematic review and meta-analysis of published studies to determine the association between metformin use and TB in patients with diabetes.

METHODS

The MEDLINE, EMBASE, Information Sciences Institute (ISI) Web of Science, and Cochrane CENTRAL databases were searched from their inception to 15 April 2019. Studies that evaluated the use of metformin and TB disease were included. The quality of each study was evaluated through the Newcastle-Ottawa Scale (NOS). For pooled data, the relative risk (RR) and 95% confidence intervals (CIs) were calculated; otherwise, a systematic review.

RESULTS

Seventeen observational studies were included, all of which indicated a low risk of bias according to the NOS. The pooled analysis showed that metformin use was associated with a significantly lower active TB incidence and mortality among individuals with DM (RR = 0.51; 95% CI, 0.38-0.69, P ⩽ 0.001) and with TB-DM (RR = 0.34; 95% CI, 0.20-0.57, P ⩽ 0.001), respectively.

CONCLUSIONS

This meta-analysis indicated metformin use is related to benefits in both prevention and treatment outcomes of tuberculosis among patients with diabetes. Prospective clinical trials are needed to confirm these associations.

Differed IL-1 Beta Response between Active TB and LTBI Cases by Ex Vivo Stimulation of Human Monocyte-Derived Macrophage with TB-Specific Antigen

Background

The difference of macrophage-specific interleukin-1 beta (IL-1b) response between latent tuberculosis infection (LTBI) and active tuberculosis (TB) remains less studied.

Method

We performed this prospective study and recruited active TB patients, contacts with LTBI, and uninfected contacts. The gene and protein expression of human monocyte-derived macrophage (hMDM) after ex vivo stimulation by early secretory antigenic target-6KD (ESAT-6) and tuberculin purified protein derivatives (PPD) was studied by real-time PCR and flow cytometry. The effect of caspase-1 inhibitor was also studied.

Result

The IL-1b gene expression after 6 hr ESAT-6 1 μg/ml stimulation was different among active TB patients (n = 12), LTBI cases (n = 12), and uninfected contacts (n = 23) (log fold change: 0.98 ± 1.26 vs. 2.20 ± 0.96 vs. 2.20 ± 0.96, P = 0.013). The IL-1b gene expression at 24 hours was higher than that at 6 hours in LTBI cases (n = 4) and uninfected contacts (n = 6). After 24 hr ESAT-6 1 μg/ml stimulation, the percentage of IL-1b-expressed hMDM was borderline lower in the active TB patients (n = 9) than in the LTBI cases (n = 10) (14.0 ± 11.2% vs. 31.6 ± 22.5%, P = 0.065). Compared with ESAT-6 1 μg/ml stimulation but without the addition of caspase-1 inhibitor (CasI) (55.6 ± 16.3%), the percentage of IL-1b-positive hMDMs decreased after addition of CasI (50 μg/ml CasI: 49.8 ± 18.2%, P = 0.078; 100 μg/ml CasI: 46.6 ± 20.8%, P = 0.030; 150 μg/ml CasI: 33.7 ± 15.5%, P = 0.016).

Conclusions

This study revealed that macrophage-specific IL-1b response differed among different stages of Mycobacterium tuberculosis infection. The role of IL-1b and inflammasome in the process of LTBI progressing to active TB warrants further investigation.

Changes in Host Response to Mycobacterium tuberculosis Infection Associated With Type 2 Diabetes: Beyond Hyperglycemia

Tuberculosis (TB) remains as the first cause of death among infectious diseases worldwide. Global incidence of tuberculosis is in part coincident with incidence of type 2 diabetes (T2D). Incidence of T2D is recognized as a high-risk factor that may contribute to tuberculosis dissemination. However, mechanisms which favor infection under T2D are just starting to emerge. Here, we first discuss the evidences that are available to support a metabolic connection between TB and T2D. Then, we analyze the evidences of metabolic changes which occur during T2D gathered thus far for its influence on susceptibility to M. tuberculosis infection and TB progression, such as hyperglycemia, increase of 1AC levels, increase of triglycerides levels, reduction of HDL-cholesterol levels, increased concentration of lipoproteins, and modification of the activity of some hormones related to the control of metabolic homeostasis. Finally, we recognize possible advantages of metabolic management of immunity to develop new strategies for treatment, diagnosis, and prevention of tuberculosis.

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.