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

Pharmacokinetics-pharmacodynamics of first-line antitubercular drugs: a comparative study in tuberculosis patients with and without concomitant diabetes mellitus

PURPOSE

To observe the variability in the plasma concentrations and pharmacokinetic-pharmacodynamic (PK-PD) profiles of first-line antitubercular drugs in pulmonary tuberculosis (TB) patients with and without diabetes mellitus (DM).

METHODS

Newly diagnosed pulmonary TB patients aged 18-60 years with or without DM were included in the study. Group I (n = 20) included patients with TB, whereas group II (n = 20) included patients with both TB and DM. After 2 weeks of therapy, plasma concentrations and other PK-PD parameters were determined. Improvements in clinical features, X-ray findings, sputum conversion, and adverse drug reactions (ADRs) were assessed after 2 months of therapy.

RESULTS

Isoniazid displayed non-significantly higher plasma concentrations in diabetic patients, along with a significantly (P < 0.05) longer elimination half-life (t1/2). Rifampicin plasma concentrations at 4, 8, and 12 h were significantly (P < 0.05) lower, and it displayed significantly (P < 0.05) lower area under the curve (AUC0-12 and AUC0-∞), shorter t1/2, higher clearance (Cl), and a lower AUC0-∞/MIC ratio in diabetic patients. Pyrazinamide and ethambutol showed non-significantly higher plasma concentrations, AUC0-12, AUC0-∞, and t1/2 in diabetic patients. The improvements in clinical features, X-ray findings, sputum conversion, and ADRs were comparable in both groups.

CONCLUSIONS

The presence of DM in TB patients affects the PK-PD parameters of isoniazid, rifampicin, pyrazinamide, and ethambutol variably in the Indian population. Studies with a larger number of patients are required to further elucidate the role of DM on the PK-PD profile of first-line antitubercular drugs and treatment outcomes in TB patients with concomitant DM.

TRIAL REGISTRATION

CTRI/2021/08/035578 dated 11/08/2021.

Drug Exposure and Treatment Outcomes in Patients With Multidrug-Resistant Tuberculosis and Diabetes Mellitus: A Multicenter Prospective Cohort Study From China

BACKGROUND

The management of multidrug-resistant tuberculosis (MDR-TB) remains challenging. Treatment outcome is influenced by multiple factors; the specific roles of diabetes and glycemic control remain uncertain. This study aims to assess the impact of glycemic control on drug exposure, to investigate the association between drug exposure and treatment outcomes, and to identify clinically significant thresholds predictive of treatment outcome, among patients with diabetes.

METHODS

This multicenter prospective cohort study involved patients with confirmed MDR-TB and diabetes. Drug exposure level was estimated by noncompartmental analysis. The minimum inhibitory concentrations (MICs) were determined for the individual Mycobacterium tuberculosis isolates. The influence of poor glycemic control (glycated hemoglobin ≥7%) on drug exposure and the associations between drug exposure and treatment outcome were evaluated by univariate and multivariate analysis. Classification and regression tree analysis was used to identify the drug exposure/susceptibility thresholds.

RESULTS

Among the 131 diabetic participants, 43 (32.8%) exhibited poor glycemic control. Poor glycemic control was independently associated with decreased exposure to moxifloxacin, linezolid, bedaquiline, and cycloserine, but not clofazimine. Additionally, a higher ratio of drug exposure to susceptibility was found to be associated with a favorable MDR-TB treatment outcome. Thresholds predictive of 6-month culture conversion and favorable outcome were bedaquiline area under the concentration-time curve (AUC)/MIC ≥245 and moxifloxacin AUC/MIC ≥67, demonstrating predictive accuracy in patients, regardless of their glycemic control status.

CONCLUSIONS

Glycemic control and optimal TB drug exposure are associated with improved treatment outcomes. This dual management strategy should be further validated in randomized controlled trials of patients with MDR-TB and diabetes.

A Comparative Investigation on Cytokine Expression in Pulmonary Tuberculosis and Comorbidity with Type 2 Diabetes Mellitus

BACKGROUND

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), with a high global prevalence and mortality rate. To control the gruesome pathogen, a deep understanding of pathophysiology and host-pathogen interaction is essential for early diagnosis and novel drug development. Cytokines play a crucial role in infection and susceptibility, and their expressions could serve as potential biomarkers to enhance our understanding of Mtb pathophysiology for improved therapeutic approaches. This cross-sectional study investigates the levels of four important T-cell immune-mediated cytokines: interleukins (IL-6 and IL-10), interferon-gamma (IFN-γ), and tumor necrosis factor-alpha in 80 cohort samples, with 20 people in each group.

METHODS

Following proper ethics and patient consent, we collected blood samples and isolated serum from all four groups: TB, type 2 diabetes mellitus (T2DM), type 2 diabetes-TB comorbidity (T2DM + TB), and a healthy individual as a control group (C). Furthermore, cytokine expression was measured in individual serum samples through the enzyme-linked immunosorbent assay method using commercial kits (Diaclone, French). Statistical significance was observed by analyzing triplicate data using t-tests and the one-way ANOVA method with GraphPad Prism 10.

RESULTS

The results showed that all four cytokine levels were higher (P ≤ 0.0001) than the control, especially IL-6, IL-10, and IFN-γ, which were found to be upregulated in T2DM + TB samples (P ≤ 0.0001) than individual TB or T2DM samples.

CONCLUSION

The high levels of cytokines in comorbidity cases raise the risk of insulin resistance and the severity of TB infection. These levels of expression could be used to keep track of the Mtb infection status or severity, aid in early diagnosis as a possible biomarker, and suggest possible treatment plans.

Evaluation of Systemic Inflammation Before and After Standard Anti-tuberculosis Treatment in Patients With Active Pulmonary Tuberculosis and Diabetes Mellitus

Background Diabetes mellitus (DM) is a common comorbidity of active pulmonary tuberculosis (APTB) that increases the risk of treatment failure during anti-tuberculosis chemotherapy. Evaluating systemic inflammatory response could help determine differences in response to treatment between APTB patients and those with APTB and DM. Methodology To explore changes in systemic inflammation, measured by a set of inflammatory mediators in subjects with APTB and TBDM before and after six months of anti-tuberculosis chemotherapy, 30 APTB and nine TBDM subjects underwent cytokine testing, including interleukin (IL)-6, IL-8, IL-10, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta 1 (TGF-β1) by enzyme-linked immunosorbent assay, C-reactive protein by nephelometry, and sialic acid by colorimetric assay at baseline and following six months of standard anti-tuberculosis treatment. Sputum smear microscopy or molecular biology (Xpert MTB/RIF) was used for diagnosis, and sputum smear microscopy was performed monthly during the treatment of the patient with pulmonary tuberculosis to evaluate his evolution. Principal component analysis examined changes in the inflammatory status. Results Both groups showed negative sputum smear microscopy in the sixth month after starting anti-tuberculosis chemotherapy. TGF-β1 was found to be significantly higher in subjects with TBDM before treatment compared to APTB patients (p<0.001), and systemic inflammation continued only in TBDM subjects after treatment (accumulation and persistence of inflammatory mediators like IL-6, IL-8, IL-10, IFN-γ, TNF-α, TGF-β1, C-reactive protein, and sialic acid in blood). On the other hand, the mediators IFN-γ, C-reactive protein, and total sialic acid were found to be most influential in distinguishing pre- and post-treatment inflammatory response in subjects with APTB without DM. Conclusions Inflammatory mediators analyzed in combination, including IFN-γ, CRP, and total sialic acid, may be useful in evaluating the systemic inflammatory response in subjects with APTB and TBDM before and after anti-tuberculosis treatment. Determining these mediators revealed persistent systemic inflammation in TBDM subjects after six months of standard tuberculosis treatment, despite negative sputum smear microscopy results and good glycemic control. This suggests a need for inflammation-modulating therapies during tuberculosis control. Finally, monitoring sputum smear microscopy results alongside the determination of proposed inflammatory mediators (IFN-γ, CRP, and total sialic acid) are effective in evaluating the response to anti-tuberculosis treatment in APTB subjects without DM, warranting further investigation.

TNF in Human Tuberculosis: A Double-Edged Sword

TNF, a pleiotropic proinflammatory cytokine, is important for protective immunity and immunopathology during Mycobacterium tuberculosis (Mtb) infection, which causes tuberculosis (TB) in humans. TNF is produced primarily by phagocytes in the lungs during the early stages of Mtb infection and performs diverse physiological and pathological functions by binding to its receptors in a context-dependent manner. TNF is essential for granuloma formation, chronic infection prevention, and macrophage recruitment to and activation at the site of infection. In animal models, TNF, in cooperation with chemokines, contributes to the initiation, maintenance, and clearance of mycobacteria in granulomas. Although anti-TNF therapy is effective against immune diseases such as rheumatoid arthritis, it carries the risk of reactivating TB. Furthermore, TNF-associated inflammation contributes to cachexia in patients with TB. This review focuses on the multifaceted role of TNF in the pathogenesis and prevention of TB and underscores the importance of investigating the functions of TNF and its receptors in the establishment of protective immunity against and in the pathology of TB. Such investigations will facilitate the development of therapeutic strategies that target TNF signaling, which makes beneficial and detrimental contributions to the pathogenesis of TB.

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.

Diabetic Pneumopathy- A Novel Diabetes-associated Complication: Pathophysiology, the Underlying Mechanism and Combination Medication

BACKGROUND

The "diabetic lung" has been identified as a possible target organ in diabetes, with abnormalities in ventilation control, bronchomotor tone, lung volume, pulmonary diffusing capacity, and neuroadrenergic bronchial innervation.

OBJECTIVE

This review summarizes studies related to diabetic pneumopathy, pathophysiology and a number of pulmonary disorders including type 1 and type 2 diabetes.

METHODS

Electronic searches were conducted on databases such as Pub Med, Wiley Online Library (WOL), Scopus, Elsevier, ScienceDirect, and Google Scholar using standard keywords "diabetes," "diabetes Pneumopathy," "Pathophysiology," "Lung diseases," "lung infection" for review articles published between 1978 to 2023 very few previous review articles based their focus on diabetic pneumopathy and its pathophysiology.

RESULTS

Globally, the incidence of diabetes mellitus has been rising. It is a chronic, progressive metabolic disease. The "diabetic lung" may serve as a model of accelerated ageing since diabetics' rate of respiratory function deterioration is two to three-times higher than that of normal, non-smoking people.

CONCLUSION

Diabetes-induced pulmonary dysfunction has not gained the attention it deserves due to a lack of proven causality and changes in cellular properties. The mechanism underlying a particular lung illness can still only be partially activated by diabetes but there is evidence that hyperglycemia is linked to pulmonary fibrosis in diabetic people.

Impact of diabetes itself and glycemic control status on tuberculosis

Objectives

To explore the impact of diabetes itself and glycemic control status on tuberculosis (TB).

Methods

A total of 3393 patients with TB and diabetes mellitus (DM) who were hospitalized in the Public Health Clinical Center of Chengdu from January 1, 2019, to December 31, 2021, were retrospectively included and divided into three groups according to baseline glycemic control status: two groups according to glycemic status at discharge, two groups according to cavity occurrence, three groups according to sputum results, and three groups according to lesion location. The influencing factors and the differences in cavity occurrence, sputum positivity and lesion location among different glycemic control groups or between different glycemic status groups were analyzed.

Results

In this TB with DM cohort, most of the subjects were male, with a male to female ratio of 4.54:1, most of them were 45-59 years old, with an average age of 57.44 ± 13.22 years old. Among them, 16.8% (569/3393) had cavities, 52.2% (1770/3393) were sputum positive, 30.4% (1030/3393) had simple intrapulmonary lesions, 68.1% (2311/3393) had both intra and extrapulmonary lesions, only 15.8% (537/3393) had good glycemic control,16.0% (542/3393) and 68.2% (2314/3393) had fair and poor glycemic control, respectively. Compared with the non-cavity group, the sputum-negative group and the extrapulmonary lesion group, the cavity group, sputum-positive group, intrapulmonary lesion group and the intra and extrapulmonary lesion group all had higher fasting plasma glucose (FPG) and glycosylated hemoglobin A 1c (HbA1c) and lower good glycemic control rates at admission (all P<0.001). Another aspect, compared with the good glycemic control group, the poor glycemic control group had a higher cavity occurrence rate, sputum positive rate, and greater proportion of intrapulmonary lesions. Moreover, FPG and HbA1c levels and poor glycemic control were significantly positively correlated with cavity occurrence, sputum positivity, and intrapulmonary lesions and were the main risk factors for TB disease progression. On the other hand, cavity occurrence, sputum positivity, and intrapulmonary lesions were also main risk factors for hyperglycemia and poor glycemic control.

Conclusion

Diabetes itself and glycemic control status could impact TB disease. Good glycemic control throughout the whole process is necessary for patients with TB and DM to reduce cavity occurrence and promote sputum negative conversion and lesion absorption.

Comparison of CD4+/CD8+ Lymphocytic Subpopulations Pre- and Post-Antituberculosis Treatment in Patients with Diabetes and Tuberculosis

Is there a CD4+ and CD8+ immunity alteration in patients with pulmonary tuberculosis (TB) and diabetes (DM) that does not recover after antituberculosis treatment? This prospective comparative study evaluated CD4+ and CD8+ lymphocytic subpopulations and antituberculosis antibodies in patients with diabetes and tuberculosis (TB-DM), before and after antituberculosis treatment. CD4+ T cell counts were lower in patients with TB-DM compared to those with only TB or only DM, and these levels remained low even after two months of anti-TB treatment. Regarding the CD8+ T cell analysis, we identified higher blood values in the DM-only group, which may be explained by the high prevalence of latent tuberculosis (LTBI) in patients with DM. IgM antituberculosis antibodies levels were elevated in patients with only TB at baseline, and 2 months post-anti-TB treatment, IgG did not express any relevant alterations. Our results suggest an alteration in CD4+ immunity in patients with TB-DM that did not normalize after antituberculosis treatment.

Impaired resolution of blood transcriptomes through tuberculosis treatment with diabetes comorbidity

BACKGROUND

People with diabetes are more likely to develop tuberculosis (TB) and to have poor TB-treatment outcomes than those without. We previously showed that blood transcriptomes in people with TB-diabetes (TB-DM) co-morbidity have excessive inflammatory and reduced interferon responses at diagnosis. It is unknown whether this persists through treatment and contributes to the adverse outcomes.

METHODS

Pulmonary TB patients recruited in South Africa, Indonesia and Romania were classified as having TB-DM, TB with prediabetes, TB-related hyperglycaemia or TB-only, based on glycated haemoglobin concentration at TB diagnosis and after 6 months of TB treatment. Gene expression in blood at diagnosis and intervals throughout treatment was measured by unbiased RNA-Seq and targeted Multiplex Ligation-dependent Probe Amplification. Transcriptomic data were analysed by longitudinal mixed-model regression to identify whether genes were differentially expressed between clinical groups through time. Predictive models of TB-treatment response across groups were developed and cross-tested.

RESULTS

Gene expression differed between TB and TB-DM patients at diagnosis and was modulated by TB treatment in all clinical groups but to different extents, such that differences remained in TB-DM relative to TB-only throughout. Expression of some genes increased through TB treatment, whereas others decreased: some were persistently more highly expressed in TB-DM and others in TB-only patients. Genes involved in innate immune responses, anti-microbial immunity and inflammation were significantly upregulated in people with TB-DM throughout treatment. The overall pattern of change was similar across clinical groups irrespective of diabetes status, permitting models predictive of TB treatment to be developed.

CONCLUSIONS

Exacerbated transcriptome changes in TB-DM take longer to resolve during TB treatment, meaning they remain different from those in uncomplicated TB after treatment completion. This may indicate a prolonged inflammatory response in TB-DM, requiring prolonged treatment or host-directed therapy for complete cure. Development of transcriptome-based biomarker signatures of TB-treatment response should include people with diabetes for use across populations.

Helminth species dependent effects on Th1 and Th17 cytokines in active tuberculosis patients and healthy community controls

Despite that the impact of different helminth species is not well explored, the current dogma states that helminths affect the Th1/Th2 balance which in turn affects the risk of tuberculosis (TB) reactivation and severity of disease. We investigated the influence of helminth species on cytokine profiles including IL-17A in TB patients and healthy community controls (CCs). In total, 104 newly diagnosed pulmonary TB patients and 70 HIV negative and QuantiFERON negative CCs in Gondar, Ethiopia were included following helminth screening by stool microscopy. Plasma samples and ex vivo stimulation of peripheral blood mononuclear cells (PBMCs) with purified protein derivative (PPD) and Staphylococcus enterotoxin B (SEB) was used to determine cytokine profiles by cytometric bead array. In CCs, Ascaris lumbricoides or Schistosoma mansoni infections were associated with an impaired Th1-type response (IFN-gamma, IL-6 and TNF-alpha) in PBMCs mainly with SEB stimulations, whereas in TB patients only hookworm infection showed a similar pattern. Among CCs, the IL-17A response in PBMCs stimulated with SEB was higher only for S. mansoni, whereas in TB patients, the elevated systemic IL-17A plasma level was significantly suppressed in hookworm infected TB patients compared to patients without helminth coinfection. Following treatment of TB and helminth infection there was a general decrease in ex vivio IL-10 and TNF-alpha production in unstimulated, PPD or SEB stimulated PBMCs that was the most pronounced and significant in TB patients infected with S. mansoni, whereas the follow-up levels of IFN-gamma and IL-17A was significantly increased only in TB patients without helminth coinfection from PBMCs stimulated mainly with SEB. In summary, in addition to confirming helminth specific effects on the Th1/Th2 response before and after TB treatment, our novel finding is that IL-17A was impaired in helminth infected TB patients especially for hookworm, indicating a helminth species-specific immunoregulatory effect on IL-17A which needs to be further investigated.

Impact of Diabetes Mellitus on the Immunity of Tuberculosis Patients: A Retrospective, Cross-Sectional Study

Background

Tuberculosis (TB) is an infectious disease that poses a significant health threat and is one of the leading causes of death worldwide. Diabetes mellitus (DM) has high morbidity and mortality rates. Previous studies have reported that comorbidities can influence one another and aggravate immune disorders. A systematic and comprehensive evaluation of the immune status of patients with TB and DM (TB-DM) is helpful for early clinical immune intervention and for promoting the recovery of patients with TB-DM.

Methods

This study included 159 patients with TB without DM (TB-NDM) and 168 patients with TB-DM. Interferon-γ (IFN-γ) release assays (IGRAs) and TB-specific antibodies against 38kD+16kD proteins were used to detect humoral and cellular immune responses. Flow cytometry was used to analyze the absolute counts of the lymphocyte subsets.

Results

There was no significant difference in the positive rate of enzyme-linked immunospot (ELISPOT) assays, enzyme linked immunosorbent assay (ELISA), and 38kD+16kD antibodies between the TB-DM and TB-NDM groups. Pulmonary lobe lesion and cavity formation rates were significantly higher in patients with TB-DM with poor glycemic control than patients with TB-NDM and TB-DM with normal glycemic control. The absolute counts of T lymphocytes, CD8+ T lymphocytes, and B lymphocytes in patients with TB-DM were markedly lower than those in patients with TB-NDM. The absolute counts of T lymphocytes and CD8+ T lymphocytes in patients with TB-DM and hyperglycemia were lower than those in patients with euglycemia. Linear regression analysis revealed that the absolute counts of total T lymphocytes, CD8+ T lymphocytes, and NK cells in patients with TB-DM significantly decreased with increasing fasting blood glucose (FBG) levels.

Conclusion

Hyperglycemia is a risk factor for pulmonary cavity formation and lobe lesions in patients with TB-DM and suppresses the absolute counts of total T lymphocytes, CD8+ T lymphocytes, and NK cells in patients with TB-DM. The potential mechanism may involve the downregulation of innate and adaptive immune responses.