Adverse reactions to first-line antituberculosis drugs

Integrative exploration of 2-phenylquinolin-4(1H)-one tethered 1,2,3-triazole derivatives: A comprehensive in vitro and in silico investigation towards novel anti-tubercular agents

Novel 2-phenylquinolin-4(1H)-one threaded 1,2,3- triazoles were designed, synthesized and evaluated for in vitro activity against Mycobacterium tuberculosis which could be putatively through inhibition of carbonic anhydrase β. Molecules were synthesized in simple Schottan Baumann reaction for amide synthesis. Purified compounds were screened for antitubercular and antibacterial activities. Among them, 1-((1-(2-methoxyphenyl)-1H-1,2,3-triazol-4-yl)methyl)-2-phenylquinolin-4(1H)-one 9j with 2-methoxy at the ortho position of phenyl ring indicated significant antitubercular activity with MIC value of 6.25, 3.12 and 3.12 μg/ml antimicrobial activity against Mycobacterium tuberculosis, gram positive and gram negative strain. The molecular docking and dynamics studies demonstrated that the compound 9j occupied the Zn-binding site of the enzyme with docking energy of -6.2 kcal mol-1. In silico ADME studies indicated that the synthesized compounds have good drug likeliness. The findings explore and present a potential series of antimycobacterial agents in the hope of developing new and advanced therapeutics for tuberculosis.

Endoplasmic reticulum stress inhibition preserves mitochondrial function and cell survival during the early onset of isoniazid-induced oxidative stress

A comprehensive understanding of isoniazid (INH)-mediated hepatotoxic effects is essential for developing strategies to predict and prevent severe liver toxicity in tuberculosis treatment. In this study, we used multi-omics profiling in vitro to investigate the toxic effects of INH, revealing significant involvement of endoplasmic reticulum (ER) stress, mitochondrial impairment, redox imbalance, and altered metabolism. Additional analysis using transcriptomics data from repeated time-course INH treatments on human hepatic microtissues revealed that cellular responses to ER stress and oxidative stress happened prior to disturbances in mitochondrial complexes. Mechanistic validation studies using time-lapse measurements of cytosolic and mitochondrial reactive oxygen species (ROS) revealed that INH initially triggered cytosolic ROS increasement and Nrf2 signaling pathway activation before mitochondrial ROS accumulation. Molecular imaging showed that INH subsequently disrupted mitochondrial function by impairing respiratory complexes I-IV and caused mitochondrial membrane proton leakage without affecting mitochondrial complex V, leading to mitochondrial depolarization and reduced ATP production. These disturbances enhanced mitochondrial fission and mitophagy. Our findings highlight the potential of inhibiting ER stress during early INH exposure to mitigate cytosolic and mitochondrial oxidative stress. We also revealed the critical role of Nrf2 signaling in protecting hepatocytes under INH-induced oxidative stress by maintaining redox homeostasis and enabling metabolic reprogramming through regulating antioxidant gene expression and cellular lipid abundance. Alternative antioxidant pathways, including selenocompound metabolism, HIF-1 signaling, and the pentose phosphate pathway, also responded to INH-induced oxidative stress. Collectively, our study emphasizes the importance of ER stress, redox imbalance, metabolic changes, and mitochondrial dysfunction that underlie INH-induced hepatotoxicity.

Patient Determinants and Effects on Adherence of Adverse Drug Reactions to Tuberculosis Treatment: A Prospective Cohort Analysis

BACKGROUND

Adverse drug reactions (ADRs) to tuberculosis (TB) medications make treatment completion challenging. We investigated the impact of alcohol, human immunodeficiency virus (HIV), and other patient determinants on ADRs and treatment adherence.

METHODS

We administered monthly ADR questionnaires to participants with TB in Worcester, South Africa. Adherence was defined as the proportion of observed doses on days when directly observed therapy was attempted. We used regression modeling to identify associations between age, sex, HIV status, alcohol, and smoked substance use with ADRs and adherence.

RESULTS

Of 286 participants, 70 (24.5%) had moderate alcohol use (phosphatidylethanol [PEth], 20-200 ng/mL), 81 (28.3%) had heavy alcohol use (PEth, >200 ng/mL), and 81 (28.3%) had HIV. A total of 156 (54.5%) reported ≥1 ADR, with maximum severity of moderate (75.6%) or mild (22.4%). Alcohol use and HIV were not associated with ADRs. The presence of ≥1 comorbidity compared with none was associated with a 46% increase in the risk of ADRs (P = .01). Nearly 70% of participants had ≥80% adherence. Among participants with moderate or severe ADRs, HIV with CD4 count <200 cells/µL compared with no HIV (rate ratio = 1.71, P = .01), moderate or severe alcohol use compared with low (rate ratio = 1.55, P = .01 and rate ratio = 1.69, P = .01), and smoked substance use compared with none (rate ratio = 1.37, P = .04) were associated with increased missed doses.

CONCLUSIONS

Half of participants on TB treatment experienced ADRs, but most remained adherent to treatment. Among participants with moderate or severe ADRs, those with poorly controlled HIV, alcohol use, or smoked substance use had lower adherence.

Preclinical liver toxicity models: Advantages, limitations and recommendations

Experimental animal models are crucial for elucidating the pathophysiology of liver injuries and for assessing new hepatoprotective agents. Drugs and chemicals such as acetaminophen, isoniazid, valproic acid, ethanol, carbon tetrachloride (CCl4), dimethylnitrosamine (DMN), and thioacetamide (TAA) are metabolized by the CYP2E1 enzyme, producing hepatotoxic metabolites that lead to both acute and chronic liver injuries. In experimental settings, acetaminophen (centrilobular necrosis), carbamazepine (centrilobular necrosis and inflammation), sodium valproate (necrosis, hydropic degeneration and mild inflammation), methotrexate (sinusoidal congestion and inflammation), and TAA (centrilobular necrosis and inflammation) are commonly used to induce various types of acute liver injuries. Repeated and intermittent low-dose administration of CCl4, TAA, and DMN activates quiescent hepatic stellate cells, transdifferentiating them into myofibroblasts, which results in abnormal extracellular matrix production and fibrosis induction, more rapidly with DMN and CCL4 than TAA (DMN > CCl4 > TAA). Regarding toxicity and mortality, CCl4 is more toxic than DMN and TAA (CCl4 > DMN > TAA). Models used to induce metabolic dysfunction-associated liver disease (MAFLD) vary, but MAFLD's multifactorial nature driven by factors like obesity, fatty liver, dyslipidaemia, type II diabetes, hypertension, and cardiovascular disease makes it challenging to replicate human metabolic dysfunction-associated steatohepatitis accurately. From an experimental point of view, the degree and pattern of liver injury are influenced by various factors, including the type of hepatotoxic agent, exposure duration, route of exposure, dosage, frequency of administration, and the animal model utilized. Therefore, there is a pressing need for standardized protocols and regulatory guidelines to streamline the selection of animal models in preclinical studies.

Nutritional supplementation during tuberculosis treatment to improve clinical symptoms: a double-blinded placebo-controlled randomized trial

Background and aims. Undernutrition coexists with tuberculosis and is associated with adverse treatment outcomes. Nutrition packages have been incorporated into tuberculosis patient care in some regions but there are little data on its effectiveness. The aim of this study is to evaluate the effect of a nutrition package on the treatment response and nutritional status of tuberculosis patients. Methods. We conducted a double-blinded placebo-controlled randomized trial in 360 pulmonary tuberculosis patients with concurrent diabetes or prediabetes. The participants were randomly assigned to receive a daily nutrition package (112 kcal, 9 g protein, and micronutrients) or a daily placebo package (112 kcal, 3 g protein, and no micronutrients) during tuberculosis treatment. The intervention lasted for six months. All participants received standard pulmonary tuberculosis treatment. The clinical symptoms, sputum smear, chest computed tomography, and nutritional status were monitored during the intervention. Results. The nutrition package improved the expectoration (intervention vs. placebo: 34.1% vs. 48.3% in week 1, 27.8% vs. 45.0% in week 2, 25.9% vs. 38.6% in week 3, 25.6% vs. 35.4% in month 1, 15.3% vs. 22.9% in month 2) and chest pain (2.3% vs. 9.0% in week 3, 3.6% vs. 8.3% in month 1, 4.3% vs. 10.0% in month 2, 1.8% vs. 6.4% in month 4). The nutrition package also increased hemoglobin, albumin, and lymphocyte counts. The nutrition package did not influence the sputum smear conversion in the whole population [hazard ratio (95% CI): 1.031 (0.685, 1.550), P = 0.885], but accelerated the conversion in patients without cavity [2.583 (1.180, 5.656), P = 0.018]. Conclusions. The nutrition package improved the clinical symptoms (e.g. chest pain and expectoration) and alleviated undernutrition (e.g. anemia and hypoproteinemia) among tuberculosis patients. The study was registered at the China Clinical Trial Registry Center (no. ChiCTR1900022294; https://www.chictr.org.cn).

Insights to the role of phytoconstituents in aiding multi drug resistance - Tuberculosis treatment strategies

Multidrug resistant tuberculosis (MDR-TB) have emerged as a global challenge. There are several underlying mechanisms which are involved in causing mycobacterial resistance towards antitubercular agents including post translational modifications, efflux pumps and gene mutations. This resistance necessitates the investigation of complementary therapeutic options including the use of bioactive compounds from plants. Recent studies have focused on recognising and isolating the characteristics of these compounds to assess their potential against MDR-TB. Phytoconstituents such as alkaloids, flavonoids, terpenoids, glycosides, and essential oils have shown promising antimicrobial activity against Mycobacterium tuberculosis. These compounds can either directly kill or inhibit the growth of M. tuberculosis or enhance the immune system's ability to fight against the infection. Some studies suggest that combining phytoconstituents with standard antitubercular medications works synergistically by enhancing the efficacy of drug, potentially lowering the associated risk of side effects and eventually combating resistance development. This review attempts to elucidate the potential of phytoconstituents in combating resistance in MDR-TB which hold a promise to change the course of treatment strategies in tuberculosis.

A novel C-4-modified isotetrone acts as a potent bio-enhancer to augment the activities of anti-tuberculosis drugs against Mycobacterium tuberculosis

Mycobacterium tuberculosis is a deadly pathogen that claims millions of lives every year. Current research focuses on finding new anti-tuberculosis drugs that are safe and effective, with lesser side effects and toxicity. One important approach is to identify bio-enhancers that can improve the effectiveness of anti-tuberculosis drugs, resulting in reduced doses and shortened treatment times. The present study investigates the use of C-4 modified isotetrones as bio-enhancers. A series of studies suggest an isotetrone, labeled as C11, inhibits growth, improves MIC, MBC and enhances the killing of M. tuberculosis H37Rv strain when used in combination with the first line and injectable anti-TB drugs in a dose-dependent manner. The combination of C11 and rifampicin also reduces the generation of spontaneous mutants against rifampicin and reaches a mutation prevention concentration (MPC) with moderate rifampicin concentrations. The identified compounds are effective against the MDR strain of M. tuberculosis and non-cytotoxic in HepG2 cells. We find that C11 induces the generation of reactive oxygen species (ROS) inside macrophages and within bacteria, resulting in better efficacy.

Antimycobacterial Activity of Solid Lipid Microparticles Loaded with Ursolic Acid and Oleanolic Acid: In Vitro, In Vivo, and Toxicity Assessments

Ursolic acid (UA) and oleanolic acid (OA) are hydrophobic triterpenoid isomers with demonstrated anti-mycobacterial (Mtb) and immune-regulatory properties, although their poor solubility limits clinical use. We report the development of solid lipid microparticles (SLMs) as delivery vehicles for UA and OA and evaluate their anti-Mtb efficacy in vitro and in vivo, as well as their acute toxicity. SLMs measured 0.7-0.89 µM in size, with complete in vitro release of OA and UA at 40 and 32 h, respectively. The minimum inhibitory concentration (MIC) of SLMs loaded with OA and UA was 40 µg/mL SLMs + 20 µg/mL OA + 20 µg/mL UA for drug-sensitive Mtb and 80 µg/mL SLMs + 40 µg/mL OA + 40 µg/mL UA for multidrug-resistant (MDR) Mtb. These SLMs showed an efficient reduction in Mtb burden in infected alveolar macrophages. In a murine model of late-stage progressive MDR-TB, aerosolized delivery of SLMs containing OA and UA via a metered-dose inhaler significantly reduced pulmonary bacterial loads and extended survival. In vivo, acute toxicity studies revealed no mortality or signs of toxicity. These findings demonstrate that SLMs are an optimal delivery system for terpenoids, providing potent in vitro and in vivo anti-TB activity with an excellent safety profile.

DRESS syndrome and tuberculosis: Implementation of a desensitization and re-desensitization protocol to recover antituberculosis drugs in a case series at a specialized TB Unit in Lima, Peru

RATIONALE

Antituberculosis drugs (ATDs) could cause severe and rare reactions, such as Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome. Recovering ATDs might guarantee a higher cure rate for tuberculosis patients. Our aim was to evaluate the results of desensitization and re-desensitization to recover ATDs in a case series of patients with DRESS syndrome.

PATIENT CONCERNS AND DIAGNOSES

A retrospective case series study was conducted on patients with DRESS syndrome due to therapy with ATDs from 2021 to 2023. Desensitization and re-desensitization protocols, designed with an algorithm proposed by the Tuberculosis Specialized Unit of the Dos de Mayo National Hospital in Lima, Peru, were implemented.

INTERVENTIONS AND OUTCOMES

A total of 18 patients underwent desensitization or re-desensitization protocols, achieving an overall success rate of 72.2%. The average time for the development of DRESS syndrome due to ATDs was 19 days. Rifampicin (84.2%), isoniazid (68.4%), and pyrazinamide (26.3%) were identified as the main drugs responsible for this adverse reaction. All patients presented with fever and skin rash, with an average eosinophil percentage of 16.7% (interquartile range: 4.5-28.8). Organ involvement (liver, kidney, and heart) was observed in 8 patients, but only 2 patients experienced severe complications due to DRESS syndrome. A significant association was found between the number of ATDs used and eosinophil levels (P =.03).

LESSONS

The study introduced a desensitization and re-desensitization algorithm for the treatment of DRESS syndrome, notable for its safety, adaptability, and high success rate. This advancement provided healthcare professionals with safer and more effective therapeutic approaches for managing this complex condition.

Ceftriaxone-induced thrombocytopenia during tuberculosis treatment: a case report

We present a case of drug-induced immune thrombocytopenia (DITP) proven to be due to ceftriaxone instead of assumed tuberculostatic treatment in a patient with miliary tuberculosis. It is important to identify the culprit drug in DITP to avoid discontinuing essential treatment, especially when more than one drug is implicated. In these cases additional analysis (drug-dependent platelet antibody testing) should be considered to prevent unnecessary replacement of a first-line regimen of tuberculostatic treatment with an alternative treatment regime.

Distinctive antibody responses to Mycobacterium tuberculosis in pulmonary and brain infection

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), remains a global health burden. While M. tuberculosis is primarily a respiratory pathogen, it can spread to other organs, including the brain and meninges, causing TB meningitis (TBM). However, little is known about the immunological mechanisms that lead to differential disease across organs. Attention has focused on differences in T cell responses in the control of M. tuberculosis in the lungs, but emerging data point to a role for antibodies, as both biomarkers of disease control and as antimicrobial molecules. Given an increasing appreciation for compartmentalized antibody responses across the blood-brain barrier, here we characterized the antibody profiles across the blood and brain compartments in TBM and determined whether M. tuberculosis-specific humoral immune responses differed between M. tuberculosis infection of the lung (pulmonary TB) and TBM. Using a high throughput systems serology approach, we deeply profiled the antibody responses against 10 different M. tuberculosis antigens, including lipoarabinomannan (LAM) and purified protein derivative (PPD), in HIV-negative adults with pulmonary TB (n = 10) versus TBM (n = 60). Antibody studies included analysis of immunoglobulin isotypes (IgG, IgM, IgA) and subclass levels (IgG1-4) and the capacity of M. tuberculosis-specific antibodies to bind to Fc receptors or C1q and to activate innate immune effector functions (complement and natural killer cell activation; monocyte or neutrophil phagocytosis). Machine learning methods were applied to characterize serum and CSF responses in TBM, identify prognostic factors associated with disease severity, and define the key antibody features that distinguish TBM from pulmonary TB. In individuals with TBM, we identified CSF-specific antibody profiles that marked a unique and compartmentalized humoral response against M. tuberculosis, characterized by an enrichment of M. tuberculosis-specific antibodies able to robustly activate complement and drive phagocytosis by monocytes and neutrophils, all of which were associated with milder TBM severity at presentation. Moreover, individuals with TBM exhibited M. tuberculosis-specific antibodies in the serum with an increased capacity to activate phagocytosis by monocytes, compared with individuals with pulmonary TB, despite having lower IgG titres and Fcγ receptor-binding capacity. Collectively, these data point to functionally divergent humoral responses depending on the site of infection (i.e. lungs versus brain) and demonstrate a highly compartmentalized M. tuberculosis-specific antibody response within the CSF in TBM. Moreover, our results suggest that phagocytosis- and complement-mediating antibodies may promote attenuated neuropathology and milder TBM disease.

Intrahepatic cholestasis of pregnancy: Introduction and overview 2024

Considerable progress has been made to explain the aetiology of intrahepatic cholestasis of pregnancy (ICP) and of the adverse pregnancy outcomes associated with high maternal total serum bile acids (TSBAs). The reported thresholds for non-fasting TSBA associated with the risk of stillbirth and spontaneous preterm birth can be used to identify pregnancies at risk of these adverse outcomes to decide on appropriate interventions and to give reassurance to women with lower concentrations of TSBA. Data also support the use of ursodeoxycholic acid to protect against the risk of spontaneous preterm birth. A previous history of ICP may be associated with higher rates of subsequent hepatobiliary disease: if there is a suspicion of underlying susceptibility, clinicians caring for women with ICP should screen for associated disorders or for genetic susceptibility and, where appropriate, refer for ongoing hepatology review.

Rifabutin loaded inhalable β-glucan microparticle based drug delivery system for pulmonary TB

Inhalable microparticle-based anti TB drug delivery systems are being investigated extensively for Tuberculosis [TB] treatment as they offer efficient and deep lung deposition with several advantages over conventional routes. It can reduce the drug dose, treatment duration and toxic effects and optimize the drug bioavailability. Yeast derived β-glucan is a β-[1-3/1-6] linked biocompatible polymer and used as carrier for various biomolecules. Due to presence of glucan chains, particulate glucans act as PAMP and thereby gets internalized via receptor mediated phagocytosis by the macrophages. In this study, β-glucan microparticles were prepared by adding l-leucine as excipient, and exhibited 70% drug [Rifabutin] loading efficiency. Further, the sizing and SEM data of particles revealed a size of 2-4 µm with spherical dimensions. The FTIR and HPLC data confirmed the β-glucan composition and drug encapsulations efficiency of the particles. The mass median aerodynamic diameter [MMAD] and geometric standard deviation [GSD] data indicated that these particles are inhalable in nature and have better thermal stability as per DSC thermogram. These particles were found to be non-toxic upto a concentration of 80 µg/ml and were found to be readily phagocytosed by human macrophage cells in-vitro as well as in-vivo by lung alveolar macrophage. This study provides a framework for future design of inhalable β-glucan particle based host-directed drug delivery system against pulmonary TB.

A Nanopore Sequencing-based Pharmacogenomic Panel to Personalize Tuberculosis Drug Dosing

Rationale: Standardized dosing of antitubercular drugs leads to variable plasma drug levels, which are associated with adverse drug reactions, delayed treatment response, and relapse. Mutations in genes affecting drug metabolism explain considerable interindividual pharmacokinetic variability; however, pharmacogenomic assays that predict metabolism of antitubercular drugs have been lacking. Objectives: We sought to develop a Nanopore sequencing panel and validate its performance in patients with active tuberculosis (TB) to personalize treatment dosing. Methods: We developed a Nanopore sequencing panel targeting 15 SNPs in five genes affecting the metabolism of antitubercular drugs. For validation, we sequenced DNA samples (n = 48) from the 1,000 Genomes Project and compared the variant calling accuracy with that of Illumina genome sequencing. We then sequenced DNA samples from patients with active TB (n = 100) from South Africa on a MinION Mk1C and evaluated the relationship between genotypes and pharmacokinetic parameters for isoniazid (INH) and rifampin (RIF). Measurements and Main Results: The pharmacogenomic panel achieved 100% concordance with Illumina sequencing in variant identification for the samples from the 1,000 Genomes Project. In the clinical cohort, coverage was more than 100× for 1,498 of 1,500 (99.8%) amplicons across the 100 samples. Thirty-three percent, 47%, and 20% of participants were identified as slow, intermediate, and rapid INH acetylators, respectively. INH clearance was 2.2 times higher among intermediate acetylators and 3.8 times higher among rapid acetylators, compared with slow acetylators (P < 0.0001). RIF clearance was 17.3% (2.50-29.9) lower in individuals with homozygous AADAC rs1803155 G→A substitutions (P = 0.0015). Conclusions: Targeted sequencing can enable the detection of polymorphisms that influence TB drug metabolism on a low-cost, portable instrument to personalize dosing for TB treatment or prevention.

Clinical Insights: Antimicrobial Therapy for Infectious Uveitis

Infectious uveitis is a major global cause of vision impairment. Despite the eye's immune privilege, afforded by the blood-ocular barrier that restricts microbial entry, several pathogens such as bacteria, viruses, fungi, and parasites can still infiltrate and cause ocular infections and complications. Clinicians often encounter significant challenges in treating infectious uveitis due to limited or ineffective treatment options. Modern molecular techniques and imaging can aid in diagnosing and assessing intraocular infections. Various antimicrobial therapies exist, spanning topical and systemic treatments, but these are constrained by issues like drug concentration, penetration, effective duration, toxicity, and side effects. Treatment approaches also differ based on the infection's etiology. This review provides recent updates on antimicrobial therapies from a clinical perspective, covering topical, systemic, and regional treatments for infectious uveitis.

Evaluation of adverse reactions induced by anti-tuberculosis drugs among hospitalized patients in Wuhan, China: A retrospective study

The study aims to estimate the incidence and risk factors of adverse drug reactions (ADRs) induced by anti-tuberculosis (TB) drugs. A single center retrospective analysis of patients taking anti-TB therapy from January 2016 to December 2018 in the hospital was conducted. Univariate and multivariate logistic regression analysis were used to identify these risk factors of ADRs induced by anti-TB drugs. Among 1430 patients receiving anti-TB therapy, 440 (30.77%) patients showed at least 1 ADR induced by anti-TB drugs. Hyperuricemia was the most common ADR, followed by hepatic function test abnormality, liver damage and gastrointestinal reactions. Significant differences (P < .05) were also seen in diabetes, age, treatment duration, type of TB (extrapulmonary) and some therapeutic regimens between ADR group and non-ADR group, respectively. Multivariate logistic regression analysis showed that treatment duration (OR = 1.029, 95%CI[1.018-1.040], P = .000), type of TB (extrapulmonary, OR = 1.487, 95%CI[1.134-1.952], P = .004) and some therapeutic regimens (HREZ, OR = 1.425, 95%CI[0.922-2.903], P = .001; HRZS, OR = 2.063, 95% CI[1.234-3.449], P = .006; HRZ, OR = 3.623, 95%CI[2.289-5.736], P = .000) were risk factors for ADRs induced by anti-TB drugs. Anti-TB drugs usually induced the occurrence of severe and frequent adverse effects, such as hyperuricemia. Treatment duration, HREZ, HRZS and HRZ regimens, and type of TB (extrapulmonary) should be considered as high-risk factors. Thus, it should be recommended to consider optimum management during anti-TB therapy, particularly hyperuricemia monitoring and hepatic function test.

Polymorphism of CYP3A4*18 is associated with anti-tuberculosis drug-induced hepatotoxicity

Aim: The association between cytochrome P450 (CYP) gene polymorphisms and anti-tuberculosis drug-induced hepatotoxicity (ATDH) was investigated in patients with or without pre-existing liver diseases (PLD). Materials & methods: We followed 164 tuberculosis subjects, 58 with PLD and 106 without PLD. Polymorphisms in CYP2D6, CYP2C9, CYP2C19, CYP3A4 and CYP3A5 were analyzed using the TaqMan® SNP genotyping assay.Results: The CYP3A4*18 heterozygous genotype was associated with ATDH (OR: 3.24, 95% CI: 1.06-9.86) regardless of PLD presence. Among subjects without PLD, CYP3A4*18 heterozygotes had significantly higher ATDH risk (OR: 9.10, 95% CI: 1.56-53.16). Conversely, in the PLD group, CYP3A4*18 heterozygotes had lower ATDH risk (OR: 0.21, 95% CI: 0.05-0.98).Conclusion: CYP3A4*18 genotype is linked to ATDH in tuberculosis patients, with differential effects based on PLD presence.

Tuberculosis treatment monitoring tests during routine practice: study design guidance

SCOPE

The current tools for tuberculosis (TB) treatment monitoring, smear microscopy and culture, cannot accurately predict poor treatment outcomes. Research into new TB treatment monitoring tools (TMTs) is growing, but data are unreliable. In this article, we aim to provide guidance for studies investigating and evaluating TB TMT for use during routine clinical care. Here, a TB TMT would guide treatment during the course of therapy, rather than testing for a cure at the regimen's end. This article does not cover the use of TB TMTs as surrogate endpoints in the clinical trial context.

METHODS

Guidelines were initially informed by experiences during a systematic review of TB TMTs. Subsequently, a small content expert group was consulted for feedback on initial recommendations. After revision, feedback from substantive experts across sectors was sought.

QUESTIONS ADDRESSED BY THE GUIDELINE AND RECOMMENDATIONS

The proposed considerations and recommendations for studies evaluating TB TMTs for use during the treatment in routine clinical care fall into eight domains. We provide specific recommendations regarding study design and recruitment, outcome definitions, reference standards, participant follow-up, clinical setting, study population, treatment regimen reporting, and index tests and data presentation. Overall, TB TMTs should be evaluated in a manner similar to diagnostic tests, but TB TMT accuracy must be assessed at multiple timepoints throughout the treatment course, and TB TMTs should be evaluated in study populations who have already received a diagnosis of TB. Study design and outcome definitions must be aligned with the developmental phase of the TB TMT under evaluation. There is no reference standard for TB treatment response, so different reference standards and comparator tests have been proposed, the selection of which will vary depending on the developmental phase of the TMT under assessment. The use of comparator tests can assist in generating evidence. Clarity is required when reporting of timepoints, TMT read-outs, and analysis results. Implementing these recommendations will lead to higher quality TB TMT studies that will allow data to be meaningfully compared, thereby facilitating the development of novel tools to guide individual TB therapy and improve treatment outcomes.

Severe esophagitis induced by antituberculosis drugs: a case report

Tuberculosis stands as one of humanity's oldest afflictions, intrinsically intertwined with social disparities. This formidable disease spares no age group and remains the prevailing cause of infection-induced mortality worldwide, particularly in developing nations. We present a case of a 56-year-old woman with diabetes who was diagnosed with Pulmonary Tuberculosis. After receiving antituberculosis drugs as part of her treatment, she experienced a range of systemic manifestations and suffered from severe ulcerative esophagitis. This adverse reaction led to uncontrollable gastrointestinal intolerance, tragically resulting in her untimely demise. The incident underscores the potential seriousness of adverse reactions that can arise from tuberculosis treatment medications.

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.

Evaluating pediatric tuberculosis dosing guidelines: A model-based individual data pooled analysis

BACKGROUND

The current World Health Organization (WHO) pediatric tuberculosis dosing guidelines lead to suboptimal drug exposures. Identifying factors altering the exposure of these drugs in children is essential for dose optimization. Pediatric pharmacokinetic studies are usually small, leading to high variability and uncertainty in pharmacokinetic results between studies. We pooled data from large pharmacokinetic studies to identify key covariates influencing drug exposure to optimize tuberculosis dosing in children.

METHODS AND FINDINGS

We used nonlinear mixed-effects modeling to characterize the pharmacokinetics of rifampicin, isoniazid, and pyrazinamide, and investigated the association of human immunodeficiency virus (HIV), antiretroviral therapy (ART), drug formulation, age, and body size with their pharmacokinetics. Data from 387 children from South Africa, Zambia, Malawi, and India were available for analysis; 47% were female and 39% living with HIV (95% on ART). Median (range) age was 2.2 (0.2 to 15.0) years and weight 10.9 (3.2 to 59.3) kg. Body size (allometry) was used to scale clearance and volume of distribution of all 3 drugs. Age affected the bioavailability of rifampicin and isoniazid; at birth, children had 48.9% (95% confidence interval (CI) [36.0%, 61.8%]; p < 0.001) and 64.5% (95% CI [52.1%, 78.9%]; p < 0.001) of adult rifampicin and isoniazid bioavailability, respectively, and reached full adult bioavailability after 2 years of age for both drugs. Age also affected the clearance of all drugs (maturation), children reached 50% adult drug clearing capacity at around 3 months after birth and neared full maturation around 3 years of age. While HIV per se did not affect the pharmacokinetics of first-line tuberculosis drugs, rifampicin clearance was 22% lower (95% CI [13%, 28%]; p < 0.001) and pyrazinamide clearance was 49% higher (95% CI [39%, 57%]; p < 0.001) in children on lopinavir/ritonavir; isoniazid bioavailability was reduced by 39% (95% CI [32%, 45%]; p < 0.001) when simultaneously coadministered with lopinavir/ritonavir and was 37% lower (95% CI [22%, 52%]; p < 0.001) in children on efavirenz. Simulations of 2010 WHO-recommended pediatric tuberculosis doses revealed that, compared to adult values, rifampicin exposures are lower in most children, except those younger than 3 months, who experience relatively higher exposure for all drugs, due to immature clearance. Increasing the rifampicin doses in children older than 3 months by 75 mg for children weighing <25 kg and 150 mg for children weighing >25 kg could improve rifampicin exposures. Our analysis was limited by the differences in availability of covariates among the pooled studies.

CONCLUSIONS

Children older than 3 months have lower rifampicin exposures than adults and increasing their dose by 75 or 150 mg could improve therapy. Altered exposures in children with HIV is most likely caused by concomitant ART and not HIV per se. The importance of the drug-drug interactions with lopinavir/ritonavir and efavirenz should be evaluated further and considered in future dosing guidance.

TRIAL REGISTRATION

ClinicalTrials.gov registration numbers; NCT02348177, NCT01637558, ISRCTN63579542.

Unregulated medication use and complications: a case study of prolonged self-treated tuberculosis in Nepal

BACKGROUND

Tuberculosis (TB) is a global public health issue, particularly in resource-constrained countries like Nepal. This case report highlights the consequences of prolonged self-treatment and non-compliance with TB management protocols, emphasizing the need for increased awareness and intervention.

CASE PRESENTATION

A 50-year-old male from Nepal self-medicated with anti-tubercular drugs for 13 years after completing the recommended course of treatment. He experienced worsening symptoms, including respiratory distress and visual impairment. Upon evaluation, he was diagnosed with chronic cavitary pulmonary aspergillosis. The patient received comprehensive treatment, including antifungal therapy, steroids, antibiotics, and respiratory support, resulting in significant improvement.

CONCLUSIONS

This case highlights the dangers of self-treatment and non-compliance with TB management protocols. It emphasizes the importance of patient education, awareness programs, and regular follow-up to ensure treatment adherence and detect complications. The case also reveals gaps in the DOTS (Directly Observed Treatment, Short Course) program, including the need for improved surveillance, and a multidisciplinary approach. The ease of over-the-counter purchase of anti-tubercular drugs in Nepal contributed to the patient's prolonged self-medication, highlighting a concerning. The complications arising from prolonged self-medication underscore the need for increased awareness, intervention, and patient education in TB management. Improving patient education, raising awareness about the risks of self-medication, and integrating ophthalmologic evaluations into standard management are essential for better TB control in Nepal.

Prevalence, risk factors and treatment outcomes of fluoroquinolones-associated tendinopathy in tuberculosis patients at university hospital, Thailand

Background

Tuberculosis (TB) is an epidemic disease in Thailand. Fluoroquinolones are used to treat TB and have a lengthy treatment course. Therefore, many patients may have adverse effects from these medications. Tendinopathy has been reported as a significant adverse effect of fluoroquinolones. Although the mechanism of tendinopathy from fluoroquinolones is not fully understood, it can progress to a more serious consequence such as a ruptured tendon which can result in morbidity if not treated effectively.

Methods

This study was a single-centered, retrospective descriptive study conducted in patients at a tertiary-level university hospital in Thailand. TB patients who received fluoroquinolones for the treatment of TB from January 2017 to December 2019 were enrolled. This study assessed the prevalence, clinical characteristics, treatment, treatment outcomes for fluoroquinolones-associated tendinopathy, and treatment outcomes of TB.

Results

During the study period, 184 participants that were diagnosed with TB and used fluoroquinolones were enrolled in the study. 34 (18.5%) participants developed tendinopathy. The risk factors that were associated with fluoroquinolones-associated tendinopathy were younger age (<60 years) (Odd ratio (OR) 3.61; 95% CI 1.16-11.23), female (OR 3.54; 95% CI 1.58-7.90), and prolonged usage of levofloxacin (>180 days) (OR 2.61; 95%CI 1.12-6.08). All participants who developed tendinopathy received conservative treatment; the dose of fluoroquinolones was reduced in 9 (26.4%) participants, fluoroquinolones were discontinued in 7 (20.6%) participants and the rest of the participants (n = 18; 52.9%) had conservative treatment. After conservative treatment, 25 (73.5%) participants recovered from tendinopathy. For the TB treatment, 27 (79.4%) participants in the tendinopathy group completed TB treatment and none of them experienced treatment failure. On the other hand, 89 (59.3%) participants in the no tendinopathy group had completed their TB treatment and 3 (2%) of them experienced treatment failure.

Conclusions

The prevalence of fluoroquinolones-associated tendinopathy was not uncommon, and the risk of fluoroquinolones-associated tendinopathy was high in young and female patients. Levofloxacin use was related to an elevated risk of developing tendinopathy, which was dose- and duration-dependent. Conservative treatment, reducing the dose or discontinuation of fluoroquinolones successfully improved the symptoms of tendinopathy. Fluoroquinolones-associated tendinopathy did not affect the treatment of TB.

Effects of antituberculosis treatment on pregnancy outcomes in infertile women with genital tuberculosis: a systematic review

OBJECTIVES

To evaluate the efficacy of antituberculosis therapy on pregnancy outcomes in infertile women with genital tuberculosis.

DESIGN

Systematic review.

DATA SOURCES

We searched in PubMed/MEDLINE, CENTRAL and EMBASE up to 15 January 2023. Additionally, we manually search the reference lists of included studies.

ELIGIBILITY CRITERIA

We included randomised controlled trials (RCT), non-RCTs (non-RCT) and cohort studies that evaluated the effects of antituberculosis treatment on pregnancy outcomes in infertile women with genital tuberculosis compared with not receiving antituberculosis treatment or receiving the treatment for a shorter period.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data. We used Cochrane Risk of Bias 1.0 and Risk Of Bias In Non-randomised Studies tools for risk of bias assessment and meta-analysis was not performed. We used Grading of Recommendations, Assessment, Development and Evaluations approach to assess the certainty of the evidence.

RESULTS

Two RCTs and one non-RCT were included. The antituberculosis regimens were based on isoniazid, rifampicin, pyrazinamide and ethambutol for 6-12 months. In women without structural damage, very low certainty of evidence from one RCT showed that the antituberculosis treatment may have little to no effect on pregnancy, full-term pregnancy, abortion or intrauterine death and ectopic pregnancy, but the evidence is very uncertain. In women with structural damage, very low certainty of evidence from one non-RCT showed that the antituberculosis treatment may reduce the pregnancy rate (297 fewer per 1000, 95% CI -416 to -101), but the evidence is very uncertain. In addition, very low certainty of evidence from one RCT compared a 9-month vs 6-month antituberculosis treatment regimen showed similar effects between the schemes, but the evidence is very uncertain. Two RCTs reported that no adverse events of antituberculosis treatment were noted or were similar in both groups.

CONCLUSION

The effect of antituberculosis treatment on pregnancy outcomes in infertile women with genital tuberculosis is very uncertain.

PROSPERO REGISTRATION NUMBER

CRD42022273145.

A Nanopore sequencing-based pharmacogenomic panel to personalize tuberculosis drug dosing

Rationale

Standardized dosing of anti-tubercular (TB) drugs leads to variable plasma drug levels, which are associated with adverse drug reactions, delayed treatment response, and relapse. Mutations in genes affecting drug metabolism explain considerable interindividual pharmacokinetic variability; however, pharmacogenomic (PGx) assays that predict metabolism of anti-TB drugs have been lacking.

Objectives

To develop a Nanopore sequencing panel and validate its performance in active TB patients to personalize treatment dosing.

Measurements and Main Results

We developed a Nanopore sequencing panel targeting 15 single nucleotide polymorphisms (SNP) in 5 genes affecting the metabolism of isoniazid (INH), rifampin (RIF), linezolid and bedaquiline. For validation, we sequenced DNA samples (n=48) from the 1000 genomes project and compared variant calling accuracy with Illumina genome sequencing. We then sequenced DNA samples from patients with active TB (n=100) from South Africa on a MinION Mk1C and evaluated the relationship between genotypes and pharmacokinetic parameters for INH and RIF.

Results

The PGx panel achieved 100% concordance with Illumina sequencing in variant identification for the samples from the 1000 Genomes Project. In the clinical cohort, coverage was >100x for 1498/1500 (99.8%) amplicons across the 100 samples. One third (33%) of participants were identified as slow, 47% were intermediate and 20% were rapid isoniazid acetylators. Isoniazid clearance was significantly impacted by acetylator status (p<0.0001) with median (IQR) clearances of 11.2 L/h (9.3-13.4), 27.2 L/h (22.0-31.7), and 45.1 L/h (34.1-51.1) in slow, intermediate, and rapid acetylators. Rifampin clearance was 17.3% (2.50-29.9) lower in individuals with homozygous AADAC rs1803155 G>A substitutions (p=0.0015).

Conclusion

Targeted sequencing can enable detection of polymorphisms influencing TB drug metabolism on a low-cost, portable instrument to personalize dosing for TB treatment or prevention.

DprE1 Inhibitors: Enduring Aspirations for Future Antituberculosis Drug Discovery

DprE1 is a crucial enzyme involved in the cell wall synthesis of Mycobacterium tuberculosis and a promising target for antituberculosis drug development. However, its unique structural characteristics for ligand binding and association with DprE2 make developing new clinical compounds challenging. This review provides an in-depth analysis of the structural requirements for both covalent and non-covalent inhibitors, their 2D and 3D binding patterns, as well as their biological activity data in vitro and in vivo, including pharmacokinetic information. We also introduce a protein quality score (PQS) and an active-site map of the DprE1 enzyme to help medicinal chemists better understand DprE1 inhibition and develop new and effective anti-TB drugs. Furthermore, we examine the resistance mechanisms associated with DprE1 inhibitors to understand future developments due to resistance emergence. This comprehensive review offers insight into the DprE1 active site, including protein-binding maps, PQS, and graphical representations of known inhibitors, making it a valuable resource for medicinal chemists working on future antitubercular compounds.

Phages for the treatment of Mycobacterium species

Highly drug-resistant strains are not uncommon among the Mycobacterium genus, with patients requiring lengthy antibiotic treatment regimens with multiple drugs and harmful side effects. This alarming increase in antibiotic resistance globally has renewed the interest in mycobacteriophage therapy for both Mycobacterium tuberculosis complex and non-tuberculosis mycobacteria. With the increasing number of genetically well-characterized mycobacteriophages and robust engineering tools to convert temperate phages to obligate lytic phages, the phage cache against extensive drug-resistant mycobacteria is constantly expanding. Synergistic effects between phages and TB drugs are also a promising avenue to research, with mycobacteriophages having several additional advantages compared to traditional antibiotics due to their different modes of action. These advantages include less side effects, a narrow host spectrum, biofilm penetration, self-replication at the site of infection and the potential to be manufactured on a large scale. In addition, mycobacteriophage enzymes, not yet in clinical use, warrant further studies with their additional benefits for rupturing host bacteria thereby limiting resistance development as well as showing promise in vitro to act synergistically with TB drugs. Before mycobacteriophage therapy can be envisioned as part of routine care, several obstacles must be overcome to translate in vitro work into clinical practice. Strategies to target intracellular bacteria and selecting phage cocktails to limit cross-resistance remain important avenues to explore. However, insight into pathophysiological host-phage interactions on a molecular level and innovative solutions to transcend mycobacteriophage therapy impediments, offer sufficient encouragement to explore phage therapy. Recently, the first successful clinical studies were performed using a mycobacteriophage-constructed cocktail to treat non-tuberculosis mycobacteria, providing substantial insight into lessons learned and potential pitfalls to avoid in order to ensure favorable outcomes. However, due to mycobacterium strain variation, mycobacteriophage therapy remains personalized, only being utilized in compassionate care cases until there is further regulatory approval. Therefore, identifying the determinants that influence clinical outcomes that can expand the repertoire of mycobacteriophages for therapeutic benefit, remains key for their future application.

Evaluation of incidence, predictive factors and treatment considerations for asymptomatic genitourinary granulomas after intravesical bacillus Calmette-Guérin therapy

INTRODUCTION AND OBJECTIVES

Although the complications of intravesical BCG treatment are well described, asymptomatic genitourinary granulomas after BCG therapy have rarely been reported and management strategy for these conditions remains controversial. The objective of this study is to evaluate the incidence rate of asymptomatic genitourinary granuloma formation mimicking bladder cancer recurrence after intravesical bacillus Calmette-Guérin (BCG) therapy and to identify the diagnostic and treatment strategies according to patient conditions.

PATIENTS AND METHODS

A retrospective review was conducted on 162 patients who underwent intravesical BCG therapy. For patients who developed granulomas, we evaluated the time interval between BCG instillation and the development of granuloma, the presence of acid-fast bacteria on pathology specimens, culture/polymerase chain reaction results, management strategies for the lesions, and clinical outcomes.

RESULTS

Asymptomatic genitourinary masses developed in 14 patients, of whom 5 underwent histological examinations and all were confirmed to have granulomatous inflammation. The affected organs included the kidney, bladder, prostate, and penis. While four of the five patients did not receive treatment for their granulomas, one patient was administered antituberculous medication to prevent worsening of the lesion during the perioperative period of the scheduled cystoprostatectomy. None of the patients experienced worsening or recurrence of granulomatous lesions. Patients who developed asymptomatic masses (n = 14) were significantly younger than those who did not (p = 0.0076) and multivariate analysis also showed that younger age was independently associated with the development of clinically suspicious lesions (p = 0.032); however, none of the parameters were associated with histologically confirmed granuloma formation.

CONCLUSIONS

Genitourinary granulomas mimicking recurrence of carcinoma may develop in nearly 10% of patients after intravesical BCG therapy. Most patients can be managed without potentially toxic antituberculosis therapy.

Safety Profile of Medicines Used for the Treatment of Drug-Resistant Tuberculosis: A Descriptive Study Based on the WHO Database (VigiBase®)

BACKGROUND

The introduction of new drugs that increase the usage of repurposed medicines for managing drug-resistant tuberculosis (DR-TB) comes with challenges of understanding, properly managing, and predicting adverse drug reactions (ADRs). In addition to the health consequences of ADRs for the individual, ADRs can reduce treatment adherence, thus contributing to resistance. This study aimed to describe the magnitude and characteristics of DR-TB-related ADRs through an analysis of ADRs reported to the WHO database (VigiBase) in the period from January 2018 to December 2020.

METHODS

A descriptive analysis was performed on selected reports from VigiBase on the basis of medicine-potential ADR pairs. The ADRs were stratified by sex, age group, reporting country, seriousness, outcome of the reaction, and dechallenge and rechallenge.

RESULTS

In total, 25 medicines reported to be suspected individual medicines or as a fixed-dose combination in the study period were included the study. Pyrazinamide (n = 836; 11.2%) was the most commonly reported medicine associated with ADRs, followed by ethionamide (n = 783; 10.5%) and cycloserine (n = 696; 9.3%). From the report included in this analysis, 2334 (31.2%) required complete withdrawal of the suspected medicine(s), followed by reduction of the dose (77; 1.0%) and an increased dose (4; 0.1%). Almost half of the reports were serious ADRs mainly caused by bedaquiline, delamanid, clofazimine, linezolid, and cycloserine that are the backbone of the DR-TB treatment currently in use.

CONCLUSIONS

A third of the reports required medication withdrawal, which impacts treatment adherence and ultimately leads to drug resistance. Additionally, more than 40% of the reports indicated that ADRs appeared two months after the commencement of treatment, thus it's important to remain alert for the potential ADRs for the entire duration of the treatment.

PROTAC antibiotics: the time is now

INTRODUCTION

Novel antibiotics are needed to keep antibiotic resistance at bay and to improve treatment of the many drug-susceptible infections for which current therapies achieve poor cure rates. While revolutionizing human therapeutics, the concept of targeted protein degradation (TPD) by bifunctional proteolysis targeting chimeras (PROTACs) has not yet been applied to the discovery of antibiotics. A major obstacle precluding successful translation of this strategy to antibiotic development is that bacteria lack the E3 ligase-proteasome system exploited by human PROTACs to facilitate target degradation.

AREAS COVERED

The authors describe the serendipitous discovery of the first monofunctional target-degrading antibiotic pyrazinamide, supporting TPD as a viable and novel approach in antibiotic discovery. They then discuss the rational design, mechanism, and activity of the first bifunctional antibacterial target degrader BacPROTAC, enabling a generalizable approach to TPD in bacteria.

EXPERT OPINION

BacPROTACs demonstrate that linking a target directly to a bacterial protease complex can promote target degradation. BacPROTACs successfully bypass the 'middleman' E3 ligase, providing an entry strategy for the generation of antibacterial PROTACs. We speculate that antibacterial PROTACs will not only expand the target space but may also improve treatment by allowing dosage reduction, stronger bactericidal activity and activity against drug-tolerant 'persisters.'

Incidence of and Risk Factors for Acute Kidney Injury During Antituberculosis Treatment: A Prospective Cohort Study and Literature Review

INTRODUCTION

Acute kidney injury (AKI) is occasionally detected in patients receiving anti-tuberculosis (TB) treatment. This prospective cohort study is the first to investigate the incidence, risk factors, and renal outcomes of AKI during anti-TB treatment.

METHODS

This study was conducted from January 1, 2016, to May 31, 2018. Patients with a new diagnosis of TB and on standard anti-TB treatment were enrolled, and the patients received regular laboratory monitoring. AKI was defined according to the Kidney Disease: Improving Global Outcome (KDIGO) criteria. Urinalysis, renal ultrasonography, blood erythrocyte morphology, and fractional excretion of sodium were performed at AKI onset. The TB treatment regimen was adjusted by the primary physician if necessary. Risk factors for AKI were identified through Cox regression.

RESULTS

In total, 106 patients were recruited (mean age 52.6 years, 71.7% men). Eleven (10.3%) patients experienced AKI. Increased serum uric acid and hemoglobin levels were noted at AKI onset. All patients with AKI achieved renal recovery and completed anti-TB treatment containing rifampin. Age [hazard ratio (HR) 1.06 (1.02-1.11)], a higher baseline estimated glomerular filtration rate [eGFR; HR 1.04 (1.02-1.06)], and a blood eosinophil count > 350 (10⁹/L) [HR 10.99 (2.28-53.02)] were associated with a higher risk of AKI during TB treatment.

CONCLUSION

Regular pharmacovigilant monitoring revealed an incidence of renal impairment during anti-TB treatment that was higher than expected. AKI was more common in older patients with a higher eGFR and blood eosinophil count. However, the complications had no influence on TB treatment completion, and no permanent renal impairment occurred.

Impact of adverse drug reactions on the outcomes of tuberculosis treatment

BACKGROUND

Adverse drug reactions (ADR) challenge successful anti-tuberculosis treatment (ATT). The aim of this study was to evaluate the impact of ATT-associated ADR and related factors on ATT outcomes.

METHODS

A prospective cohort study of persons with tuberculosis (TB) at a referral center in Rio de Janeiro, Brazil, from 2010 to 2016. Baseline information: race, sex, schooling, economic status, tobacco, drugs and alcohol abuse, HIV-infection status and comorbidities were captured during TB screening and diagnosis. Laboratory exams were performed to confirm TB diagnosis and monitor ADRs, favorable (cure and treatment completion) and unfavorable (death, loss to follow up and failure) outcomes were prospectively captured. The Kaplan-Meier curve was used to estimate the probability of ADR-free time. A logistic regression analysis (backward elimination) was performed to identify independent associations with unfavorable outcomes.

RESULTS

550 patients were enrolled, 35.1% were people living with HIV (PLHIV) and ADR occurred in 78.6% of all participants. Smoking (OR: 2.32; 95% CI:1.34-3.99) and illicit-drug use (OR:2.02; 95% CI:1.15-3.55) were independent risk factors for unfavorable outcomes. In PLHIV, alcohol abuse and previous ART use were associated with unfavorable outcomes. In contrast, ADR increased the odds of favorable outcomes in the overall population. PLHIV more frequently experienced grade 3/4-ADR (18.36%), especially "liver and biliary system disorders". Lower CD4 counts (<100 cells/uL) were associated with hepatotoxicity (p = 0.03). ART-naïve participants presented a higher incidence of ADR in comparison with ART-experienced patients.

CONCLUSION

Substance use was associated with unfavorable outcomes, highlighting the need for better strategies to reduce this habit. In contrast, ADRs were associated with favorable outcomes. Attention to the occurrence of ADR in PLHIV is essential, especially regarding hepatotoxicity in those with high immunosuppression.

A high-throughput LC-MS/MS method for simultaneous determination of isoniazid, ethambutol and pyrazinamide in human plasma

RATIONALE

Tuberculosis (TB) remains a challenging global infectious disease, mainly affecting the lungs. First-line anti-TB drugs play a crucial role in slowing down the rapid spread of TB. In addition, the patient might benefit from therapeutic drug monitoring since it has become an accepted clinical tool for optimizing TB treatment.

METHODS

A simple and sensitive liquid chromatography/tandem mass spectrometry method was developed to monitor the plasma level of isoniazid, ethambutol and pyrazinamide in plasma samples. A one-step extraction procedure using an Ostro™ plate was applied, and extracts were analyzed by gradient elution followed by detection on a mass spectrometer by multiple reaction monitoring mode.

RESULTS

The analytes were separated within 4.2 min and over the concentration range of 0.2-10 μg/ml for isoniazid and ethambutol and 1-65 μg/ml for pyrazinamide. The method was successfully validated according to the European Medicine Agency guideline for the selectivity, linearity and lower limit of detection, precision and accuracy, matrix effect, extraction recovery, carryover, dilution integrity and stability, and applied for quantification of analytes in clinical samples from TB patients.

CONCLUSIONS

The presented method allows sensitive and reproducible determination of selected anti-TB drugs with advantages such as low sample volume requirement, short run time of analysis, one-step sample preparation procedure with capabilities for phospholipids removal, and a low quantification limit as well as a high degree of selectivity.

Quantitative Analysis of Isoniazid and Its Four Primary Metabolites in Plasma of Tuberculosis Patients Using LC-MS/MS

Isoniazid and its metabolites are potentially associated with hepatotoxicity and treatment outcomes in patients who receive antituberculosis (TB) therapy. To further understand the pharmacokinetic profiles of these molecules, a method based on LC-MS/MS was developed to determine the concentration of these compounds in human plasma. Isoniazid, acetylisoniazid, and isonicotinic acid were directly analyzed, whereas hydrazine and acetylhydrazine were determined after derivatization using p-tolualdehyde. Chromatographic separation was conducted on reversed-phase C18 columns with gradient elution, and detection was carried out in multiple reaction monitoring mode. The calibration curves were linear with correlation coefficients (r) greater than 0.9947 for all analytes. The intra- and inter-day precision was less than 13.43%, and the accuracy ranged between 91.63 and 114.00%. The recovery and matrix effect of the analytes were also consistent (coefficient of variation was less than 9.36%). The developed method successfully quantified isoniazid and its metabolites in TB patients. The method has broad applications in clinical research, including isoniazid one-point-based therapeutic drug monitoring, genotype-phenotype association studies of isoniazid metabolic profile and isoniazid-induced hepatotoxicity, and the initial dose prediction of isoniazid using population pharmacokinetic modeling.

Versatile TLC-Densitometric Methods for the Synchronous Estimation of Cinnarizine and Acefylline Heptaminol in The Presence of Potential Impurity and Their Reported Degradation Products

From evolution, thin-layer chromatography (TLC) attracts attention as a versatile technique for efficient separation and identification of many drug substances and chemicals. Owing to its simplicity and other outstanding advantages, TLC is extensively used by chromatographers in quantification and purity profiling objectives. In the present study two TLC-Densitometric methods are established and validated for the synchronous estimation of Cinnarizine (Cinn) and Acefyline Heptaminol (Acef) in the presence of Cinn/Acef reported degradation products and Thoephylline (Theo) as Acef potential impurity. The proposed methods are based on densitometric measurements of the spots of Cinn and Acef after separation from their degradation products. Separation is attained on silica gel sheet with dichloromethane: methanol: formic acid as a developing system in ratio: (15, 1, 0.5, by volume) and (15, 0.75, 0.4, by volume) for Cinn (method 1) and Acef (method 2) degradation, consecutively. Quantification is done at 254 nm over concentration ranges of 0.2-1.8 and 2-18 μg/spot for Cinn and Acef; respectively, with mean percentage recoveries of 99.18 ± 0.60/99.84 ± 0.53 and 99.19 ± 0.93/99.66 ± 0.58 for method 1 and method 2; consecutively. The two methods are fully validated and proven to be selective, robust and retained their accuracy in up to 50% of Cinn/Acef reported degradation products and Theo. Moreover, the two methods are applied to a coformulated drug product comprising Cinn and Acef showing satisfactory results. Comparison of the obtained results by the proposed methods with that of the reference ones statistically shows no significant differences.

Comparing the efficacy of different antibiotic regimens on osteomyelitis: A network meta-analysis of animal studies

Background

Despite the surge in the number of antibiotics used to treat preclinical osteomyelitis (OM), their efficacy remains inadequately assessed.

Objective

To establish network comparisons on the efficacy of antibiotic regimens on OM in animal studies.

Methods

PubMed, Embase, Web of Science, and The Cochrane Library were searched from inception to March 2022 for relevant articles. Odds ratios (ORs) were generated for dichotomous variants, and the standard mean difference (SMD) was calculated for constant variables. The predominant outcomes were the effective rate of sterility, also known as sterility rates, as well as the bacterial counts at the end of the experiments and antibiotic concentrations in serum or bone. All the network meta-analyses were performed using STATA MP 16.0. This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO; no. CRD42022316544).

Results

A total of 28 eligible studies with 1,488 animals were included for data analysis, including 13 antibiotic regimens. Regarding the effective rate of sterility, glycopeptides (GLY), linezolid (LIN), rifampicin (RIF)+β-Lactam, and β-Lactam showed significant efficacy compared with placebo (OR ranging from 0.01 to 0.08). For radiological grade, only RIF+GLY (SMD: −5.92, 95%CI: −11.65 to −0.19) showed significant efficacy compared with placebo. As for reducing bacteria count, fosfomycin (FOS), tigecycline (TIG), GLY, LIN, RIF, RIF+β-Lactam, RIF+GLY, aminoglycosides (AMI), and clindamycin (CLI) showed significant efficacy compared with placebo (SMD ranging from −6.32 to −2.62). Moreover, the bone concentrations of GLY were higher 1 h after administration and the higher blood concentrations were higher after 1 h and 4 h compared with the other antibiotics.

Conclusion

Multiple antibiotic regimens showed significant efficacy in animals with OM, including increasing effective rates of sterility, reducing bacterial counts, and lowering radiological scores. Among them, RIF+GLY was the most promising treatment regimen owing to its optimal efficacy. Based on the preclinical studies included in our meta-analysis, head-to-head clinical randomized controlled trials are required to confirm these findings in humans.

Risk Assessment of Major Adverse Cardiovascular and Cerebrovascular Events and Bleeding for Acute Myocardial Infarction With or Without Active Tuberculosis

PURPOSE

The underlying ischemic and bleeding risks of acute myocardial infarction (AMI) with active tuberculosis (TB) are unknown. The goal of this study was to explore the ischemic and bleeding risks, as well as treatment strategies during hospitalization, in patients with AMI with or without active TB.

METHODS

Patients were recruited from a tuberculosis hospital from 2014 to 2021. The primary outcomes were major cardiovascular and cerebrovascular events (MACE) and Bleeding Academic Research Consortium (BARC)-defined type 3 or 5 bleeding. Multivariate logistic regression and propensity score matching were performed for risk adjustment. Subgroups were defined according to AMI with active pulmonary TB and AMI with active TB undergoing percutaneous coronary intervention (PCI).

FINDINGS

A total of 242 patients were enrolled. Compared with AMI without active TB, AMI with active TB had a higher risk of MACE and BARC type 3 or 5 bleeding (P < 0.001 and P = 0.002, respectively). Multivariate logistic regression analysis showed that, compared with AMI without active TB, the odds ratio (OR) was 6.513 (95% CI, 2.195-19.331) for MACE in patients with AMI with active TB, and the OR was 16.074 (95% CI 3.337-77.436) for BARC type 3 or 5 bleeding in patients with AMI with active TB. After propensity score matching, AMI with active TB tended to increase the risk of MACE, although not statistically significantly (P = 0.189), and increased BARC type 3 or 5 bleeding (P < 0.001), compared with AMI without active TB. Results of subgroup analyses showed that active TB had outcomes consistent with those of the total cohort. AMI patients with active pulmonary TB who underwent PCI had a lower risk of MACE without an increase in the risk of bleeding compared with those not undergoing PCI.

IMPLICATIONS

Patients with AMI with active TB have a higher risk of MACE (or severe MACE) and bleeding than patients with AMI without active TB. However, AMI patients with active TB are still advised to undergo PCI for a high net clinical benefit.

Costs Associated with Adverse Drug Reactions Among HIV/TB Patients in Thailand

Purpose

To assess the direct and indirect costs associated with adverse drug reactions (ADRs) in patients receiving treatment regimens for human immunodeficiency virus (HIV) infection and tuberculosis (TB) in selected Thai hospitals.

Patients and Methods

This was a retrospective study conducted between October 2014 and September 2019 at three public hospitals in Thailand. Data were obtained from a medical database and spontaneous ADR reporting system of each study site. The out-of-pocket health payments and indirect costs were determined via interviewing. All costs were updated to 2021.

Results

A total of 432 eligible patients who experienced ADRs due to HIV and TB treatment, and 93 patients were interviewed to determine direct non-medical and indirect costs. The average direct medical cost for ADR was USD 5.65 for mild cases, USD 156.54 for moderate cases, and USD 1,242.45 for severe cases. For direct non-medical costs, the average cost per episode was USD 27.29 in mild ADR, USD 70.86 in moderate ADR and USD 270.66 in severe ADR. The indirect cost incurred in each mild, moderate and severe ADR was USD 41.86, USD 89.34, and USD 552.60, respectively. The Stevens-Johnson syndrome (SJS) had the highest management costs.

Conclusion

ADRs associated with anti-tuberculosis drugs and antiretroviral drugs seem to have a substantial economic impact from a societal perspective. These findings would be useful for increasing awareness and encouraging early avoidance of ADRs.

HupB, a nucleoid-associated protein, is critical for survival of Mycobacterium tuberculosis under host-mediated stresses and for enhanced tolerance to key first-line antibiotics

To survive and establish its niche, Mycobacterium tuberculosis (Mtb) engages in a steady battle against an array of host defenses and a barrage of antibiotics. Here, we demonstrate that Mtb employs HupB, a nucleoid-associated protein (NAP) as its key player to simultaneously battle and survive in these two stress-inducing fronts. Typically, NAPs are key to bacterial survival under a wide array of environmental or host-mediated stresses. Here, we report that for Mtb to survive under different macrophage-induced assaults including acidic pH, nutrient depletion, oxidative and nitrosative stresses, HupB presence is critical. As expected, the hupB knockout mutant is highly sensitive to these host-mediated stresses. Furthermore, Mtb aptly modulates HupB protein levels to overcome these stresses. We also report that HupB aids Mtb to gain tolerance to high levels of rifampicin (RIF) and isoniazid (INH) exposure. Loss of hupB makes Mtb highly susceptible to even short exposures to reduced amounts of RIF and INH. Overexpressing hupB in Mtb or complementing hupB in the hupB knockout mutant triggers enhanced survival of Mtb under these stresses. We also find that upon loss of hupB, Mtb significantly enhances the permeability of its cell wall by modulating the levels of several surface lipids including phthiocerol dimycocerosates (PDIMs), thus possibly influencing overall susceptibility to host-mediated stresses. Loss of hupB also downregulates efflux pump expression possibly influencing increased susceptibility to INH and RIF. Finally, we find that therapeutic targeting of HupB with SD1, a known small molecule inhibitor, significantly enhances Mtb susceptibility to INH and THP-1 macrophages and significantly reduces MIC to INH. Thus, our data strongly indicate that HupB is a highly promising therapeutic target especially for potential combinatorial shortened therapy with reduced INH and RIF doses.

Making cough count in tuberculosis care

Cough assessment is central to the clinical management of respiratory diseases, including tuberculosis (TB), but strategies to objectively and unobtrusively measure cough are lacking. Acoustic epidemiology is an emerging field that uses technology to detect cough sounds and analyze cough patterns to improve health outcomes among people with respiratory conditions linked to cough. This field is increasingly exploring the potential of artificial intelligence (AI) for more advanced applications, such as analyzing cough sounds as a biomarker for disease screening. While much of the data are preliminary, objective cough assessment could potentially transform disease control programs, including TB, and support individual patient management. Here, we present an overview of recent advances in this field and describe how cough assessment, if validated, could support public health programs at various stages of the TB care cascade.

A prospective observational study to evaluate Glutathione S-transferase gene polymorphism and its association with Antitubercular drugs induced liver injury in tertiary hospital

BACKGROUND

Anti-TB drugs are most common cause of idiosyncratic hepatotoxicity worldwide. Reactive metabolite formed during drug metabolism has been involved in a clinical toxicity are described as 'idiosyncratic' drug induce liver injury (DILI). We have observed the distribution of glutathione S -transferase (GST) gene polymorphism & its association with drug-induced liver injury in patients taking anti-tubercular treatment.

METHODS

A prospective observational study including 96 patients receiving anti-tubercular treatment. Blood sample was collected for LFT and gene extraction after ruling out other cause of liver injury. DNA extraction for GST gene was done follow by polymerase chain reaction to identify homozygous null mutation at GSTM1 and GSTT1 loci. Association of GSTM1 and GSTT1 gene with DILI was seen.

RESULTS

Out of 96 tubercular patients under treatment, drug induced liver injury was found in 21 (21.9%) patients and 75 does not develop DILI, GST M1 gene null mutation was observed in 14 (66.7%), GST T1 gene null mutation was observed in 9 (42.9%), Both GST gene null mutation was observed in 8 (38.1%) in DILI group.

CONCLUSION

The GSTM1 gene null mutation and both GSTM1 and T1 gene null mutation were a risk factor for the development of DILI. But there is no significant association between GSTT1 gene null mutation and DILI in TB patients.

Frequency and Management of Adverse Drug Reactions Among Drug-Resistant Tuberculosis Patients: Analysis From a Prospective Study

Drug-resistant tuberculosis (DR-TB) management is often linked with a higher rate of adverse drug reactions (ADRs) needing effective and timely management of these ADRs, which, if left untreated, may result in a higher rate of loss to follow-up of drug-resistant patients.

Study objective: The study was aimed at prospectively identifying the nature, frequency, suspected drugs, and management approaches for ADRs along with risk factors of ADRs occurrence among DR-TB patients at Nishtar Medical University, Hospital, Multan, Pakistan.

Materials and Methods: The prospective study included all the DR-TB patients enrolled for treatment from January 2016 to May 2017 at the study site. Patients were evaluated for the treatment-induced ADRs as per standard criteria of the National Tuberculosis Program, Pakistan. Multivariate logistic regression was used to assess the independent variables associated with the occurrence of ADRs.

Results: Out of 271 DR-TB patients included in the final analysis, it was observed that 55 patients (20.3%) experienced at least three ADRs. A total of 50 (18.5%) patients experienced zero adverse effects, while 15 (5.5%), 33 (12.2%), and 53 (19.6%) patients experienced one, two, and four ADRs, respectively. Gastrointestinal disturbances (66.7%), nervous system disorders (59.4%), and electrolyte disturbances (55.7%) remained the highest reported ADRs during therapy, followed by arthralgia (49.1%), ototoxicity (24%), pruritic reactions/rash (12.9%), dyspnoea (12.5%), and tinnitus (8.8%). Pulmonary cavitation at the baseline visit (p-value 0.001, OR 3.419; 95% CI (1.694–6.902) was significantly associated with the occurrence of ADRs among DR-TB patients.

Conclusion: The frequency of ADRs was high among the study cohort; however, these were managed effectively. Patients with recognized risk factors for ADRs occurrence need continuous clinical management efforts.

Single-Fluorescence ATP Sensor Based on Fluorescence Resonance Energy Transfer Reveals Role of Antibiotic-Induced ATP Perturbation in Mycobacterial Killing

The rapid emergence of multidrug-resistant/extensively drug-resistant tuberculosis (TB) is responsible for treatment failure in patients with TB and significantly endangers global public health. Recently, bioenergetics has become a new paradigm for anti-TB drug discovery and is based on the link between bacterial ATP levels and drug efficacy. A better understanding of the role of ATP fluctuations during antibiotic treatment may provide insight into antibiotic-mediated killing of mycobacteria. Here, we employed an advanced single-fluorescence FRET (fluorescence resonance energy transfer)-based ATP biosensor, ATPser, for the stable and convenient detection of intracellular ATP fluctuations in mycobacteria. This strategy correlated closely with the results obtained from conventional luminescence ATP assays, indicating the reliability of the system for bioenergetics analysis in mycobacteria. Moreover, the reporter strains expressing ATPser displayed obvious ATP changes when subjected to different stresses, such as starvation and ATP depletion. Interestingly, we observed that different antibiotics induced fluctuations in cellular ATP levels in individual cells of various magnitudes, revealing a strong connection between ATP fluctuations and drug efficacy. Furthermore, drug combinations accelerated ATP perturbation, resulting in increased cell death. We concluded that ATPser enabled real-time measurement of ATP at the single-cell level in mycobacteria, and monitoring ATP dynamics in drug-treated bacteria may shed light on novel treatment strategies.

IMPORTANCE Bioenergetics has emerged as a new paradigm for antituberculosis (anti-TB) drug discovery, and the cellular ATP level is the core indicator reflecting bacterial metabolic homeostasis. Although several bulk assays have been designed for the measurement of cellular ATP content, a more convenient strategy is required for real-time ATP measurement of single viable cells. In this study, by combining the ε-subunit of Bacillus subtilis F_oF₁-ATP synthase with a circularly permuted green fluorescent protein [(cp)GFP], we constructed a FRET-based single-fluorescence ATP sensor, ATPser, for real-time single-cell ATP detection among a mycobacterial population. Using the ATPser, we designed different drug combinations containing components that have similar/opposite effects on ATP alternation. Our results demonstrated that increased cellular ATP fluctuations were associated with depletion of mycobacterial viability, while counteracting ATP fluctuations weakened the killing effect of the drug regime. Thus, potentially efficient drug combinations can be considered based on their similar effects on mycobacterial ATP levels, and ATPser may be a useful tool to study mycobacterial bioenergetics and to guide drug regime design.

NAT2 polymorphism and clinical factors that increased antituberculosis drug-induced hepatotoxicity

Aim: Hepatotoxicity is a known adverse effect of antituberculosis drugs. The NAT2 gene polymorphism has been associated with an increased risk of antituberculosis drug-induced hepatotoxicity (ATDIH). Materials and methods: This study investigates the association of NAT2 polymorphism and clinical risk factors that may contribute to the development of ATDIH. The authors sequenced the NAT2 region of 33 tuberculosis patients who developed ATDIH and 100 tuberculosis patients who did not develop ATDIH during tuberculosis treatment. NAT2 haplotypes were inferred and NAT2 acetylator status was predicted from the combination of the inferred haplotypes. Multiple logistic regression was performed to identify possible factors that are associated with ATDIH. Results: The TT genotype of NAT2*13A and the AA genotype of NAT2*6B were found to be substantially linked with the risk of ATDIH, with odds ratios of 3.09 (95% CI: 1.37-6.95) and 3.07 (95% CI: 1.23-7.69), respectively. NAT2 slow acetylators are 3.39-times more likely to develop ATDIH. Factors that were associated with ATDIH include underlying diabetes mellitus (adjusted odds ratio [AOR] 2.96; 95% CI: 1.05-8.37), pre-treatment serum bilirubin (AOR 1.09; 95% CI: 1.02-1.16) and NAT2 slow acetylator (AOR 3.77; 95% CI: 1.51-9.44). Conclusion: Underlying diabetes mellitus, having a higher baseline bilirubin and being a slow acetylator are identified as the risk factors associated with ATDIH among patients in Malaysia.

Plant-Derived Natural Products as Lead Agents against Common Respiratory Diseases

Never has the world been more challenged by respiratory diseases (RDs) than it has witnessed in the last few decades. This is evident in the plethora of acute and chronic respiratory conditions, ranging from asthma and chronic obstructive pulmonary disease (COPD) to multidrug-resistant tuberculosis, pneumonia, influenza, and more recently, the novel coronavirus (COVID-19) disease. Unfortunately, the emergence of drug-resistant strains of pathogens, drug toxicity and side effects are drawbacks to effective chemotherapeutic management of RDs; hence, our focus on natural sources because of their unique chemical diversities and novel therapeutic applications. This review provides a summary on some common RDs, their management strategies, and the prospect of plant-derived natural products in the search for new drugs against common respiratory diseases.

SUR2A as a base for cardioprotective therapeutic strategies

BACKGROUND

ATP-sensitive K⁺ (K_ATP) channels link the metabolic state of the cell with membrane excitability and SUR2A serves as a regulatory subunit of sarcolemmal K_ATP channels. The aim of the present study was to review SUR2A-mediated cardioprotection.

METHODS AND RESULTS

A related literature search in PubMed, Scopus, Web of Science, Google Scholar, and Science direct was performed. Levels of SUR2A regulate number of fully assembled K_ATP channels in the sarcolemma. Increased numbers of sarcolemmal K_ATP channels protect cardiomyocytes against different types of stress by improving the timing of K_ATP channels opening, but, also, by catalyzing ATP production in subsarcolemmal space. Fully-assembled sarcolemmal K_ATP channels protein complex contain ATP-producing enzymes in addition to channel subunits, SUR2A and Kir6.2. An increase in the number of fully-assembled channels results in increased levels of ATP-producing enzymes and subsarcolemmal ATP, which is beneficial in ischemia. Expression of SUR2A is regulated by diverse mechanisms, including AMPK, PI3K/Akt, and ERK1/2 as well as intracellular levels of NAD+/NADH and ATP. There are many compounds and treatments that can be used to regulate SUR2A and some of them seem to be clinically viable options. The most suitable medication to use to increase SUR2A and confer cardioprotection in the clinical setting seems to be nicotinamide. It is one of the safest compounds used in clinical practice and all pre-clinical studies demonstrated that it is an efficient cardioprotective agent.

CONCLUSIONS

Taken all together, SUR2A-based cardioprotection is a likely efficient and safe cardioprotective strategy that can be quickly introduced into clinical practice.