First line anti-tuberculosis induced hepatotoxicity: incidence and risk factors

Vigilance Needed in Treating a Child with Disseminated TB: A Case Report

BACKGROUND

Tuberculosis is still one of the biggest causes of infection-related death around the world. Disseminated tuberculosis is a potentially fatal disease caused by the haematogenous spread of Mycobacterium tuberculosis. First-line anti-tuberculosis drugs include isoniazid, rifampicin, pyrazinamide, and ethambutol. The first three drugs are known to cause hepatotoxicity.

CASE PRESENTATION

We have, herein, reported a case of Drug-induced Liver Injury (DILI) due to anti-tuberculosis therapy in a one-year-old male child with disseminated tuberculosis. He was started on a fixed-dose combination of Anti-tuberculosis Therapy (ATT; isoniazid 50 mg, rifampicin 75 mg, and pyrazinamide 150 mg) and pyridoxine 10 mg orally. Initially, liver parameters were normal, but later on with the course of the treatment, there was a rapid rise in liver enzymes, suggesting liver injury.

DISCUSSION

The association between liver injury and anti-tuberculosis therapy has been confirmed by applying various causality association scales. It is obvious that proper treatment of disseminated tuberculosis can avoid the development of drug-resistant strains that can be harmful, worsening the prognosis as there are fewer therapeutic alternatives available. At the same time, there is a need to monitor the patient with ATT-induced DILI.

CONCLUSION

The diagnosis of tuberculosis in children is difficult because of the mild, nonspecific clinical presentation, which usually reflects the implicated underlying organ. In addition to prompt diagnosis and treatment of disseminated TB, careful monitoring is equally important.

Model-informed dose optimisation of polymyxin-rifampicin combination therapy against multidrug-resistant Acinetobacter baumannii

OBJECTIVES

Antimicrobial resistance is a major global threat. Because of the stagnant antibiotic pipeline, synergistic antibiotic combination therapy has been proposed to treat rapidly emerging multidrug-resistant (MDR) pathogens. We investigated antimicrobial synergy of polymyxin/rifampicin combination against MDR Acinetobacter baumannii.

METHODS

In vitro static time-kill studies were performed over 48 h at an initial inoculum of ∼107 CFU/mL against three polymyxin-susceptible but MDR A. baumannii isolates. Membrane integrity was examined at 1 and 4 h post-treatment to elucidate the mechanism of synergy. Finally, a semi-mechanistic PK/PD model was developed to simultaneously describe the time course of bacterial killing and prevention of regrowth by mono- and combination therapies.

RESULTS

Polymyxin B and rifampicin alone produced initial killing against MDR A. baumannii but were associated with extensive regrowth. Notably, the combination showed synergistic killing across all three A. baumannii isolates with bacterial loads below the limit of quantification for up to 48 h. Membrane integrity assays confirmed the role of polymyxin-driven outer membrane remodelling in the observed synergy. Subsequently, the mechanism of synergy was incorporated into a PK/PD model to describe the enhanced uptake of rifampicin due to polymyxin-induced membrane permeabilisation. Simulations with clinically utilised dosing regimens confirmed the therapeutic potential of this combination, particularly in the prevention of bacterial regrowth. Finally, results from a neutropenic mouse thigh infection model confirmed the in vivo synergistic killing of the combination against A. baumannii AB5075.

CONCLUSION

Our results showed that polymyxin B combined with rifampicin is a promising option to treat bloodstream and tissue infection caused by MDR A. baumannii and warrants clinical evaluations.

The Effect of Bergenin on Isonicotinic Acid Hydrazide and Rifampicin-Induced Liver Injury Revealed by RNA Sequencing

Bergenin (BER), a natural component of polyphenols, has a variety of pharmacological activities, especially in improving drug metabolism, reducing cholestasis, anti-oxidative stress and inhibiting inflammatory responses. The aim of this study was to investigate the effects of BER on liver injury induced by isonicotinic acid hydrazide (INH) and rifampicin (RIF) in mice. The mice model of liver injury was established with INH (100 mg/kg)+RIF (100 mg/kg), and then different doses of BER were used to intervene. The pathological morphology and biochemical indicators of mice were detected. Meanwhile, RNA sequencing was performed to screen the differentially expressed genes and signaling pathways. Finally, critical differentially expressed genes were verified by qRT-PCR and Western blot. RNA sequencing results showed that 707 genes were significantly changed in the INH+RIF group compared with the Control group, and 496 genes were significantly changed after the BER intervention. These differentially expressed genes were mainly enriched in the drug metabolism, bile acid metabolism, Nrf2 pathway and TLR4 pathway. The validation results of qRT-PCR and Western blot were consistent with the RNA sequencing. Therefore, BER alleviated INH+RIF-induced liver injury in mice. The mechanism of BER improving INH+RIF-induced liver injury was related to regulating drug metabolism enzymes, bile acid metabolism, Nrf2 pathway and TLR4 pathway.

Hepatocyte ferroptosis contributes to anti-tuberculosis drug-induced liver injury: Involvement of the HIF-1α/SLC7A11/GPx4 axis

Anti-tuberculosis drug-induced liver injury (ATB-DILI) is a common serious adverse event observed during the clinical treatment of tuberculosis. However, the molecular mechanisms underlying ATB-DILI remain unclear. A recent study has indicated that ferroptosis and lipid peroxidation may be involved in liver injury. Therefore, this study aimed to investigate the role of ferroptosis in the molecular mechanisms underlying ATB-DILI. Our results showed that anti-TB drugs induced hepatocyte damage in vivo and in vitro and inhibited BRL-3A cell activity in a dose-dependent manner, accompanied by increased lipid peroxidation and reduced antioxidant levels. Moreover, ACSL4 expression and Fe²⁺ concentration significantly increased following anti-TB drug treatment. Interestingly, anti-TB drug-induced hepatocyte damage was reversed by ferrostatin-1 (Fer-1, a specific ferroptosis inhibitor). In contrast, treatment with erastin (a ferroptosis inducer) resulted in further elevation of ferroptosis indicators. Additionally, we also found that anti-TB drug treatment inhibited HIF-1α/SLC7A11/GPx4 signaling in vivo and in vitro. Notably, HIF-1α knockdown significantly enhanced anti-TB drug-induced ferroptotic events and the subsequent exacerbation of hepatocyte damage. In conclusion, our findings indicated that ferroptosis plays a crucial role in the development of ATB-DILI. Furthermore, anti-TB drug-induced hepatocyte ferroptosis was shown to be regulated by HIF-1α/SLC7A11/GPx4 signaling. These findings shed new light on the mechanisms underlying ATB-DILI and suggest novel therapeutic strategies for this disease.

Glutathione-S-transferase genetic polymorphism and risk of hepatotoxicity to antitubercular drugs in a North-African population: A case-control study

INTRODUCTION

GST non-functional genotypes can lead to the accumulation of toxic intermediates, resulting in liver damage and increasing susceptibility to ATDH.

AIM

To investigate the impact of GST Mu (GSTM1), GST Theta (GSTT1) null genotypes, and GST Pi (GSTP1; adenosine (A) > guanine (G), rs1695) variant allele on the development of ATDH in Tunisian patients treated with anti-tuberculosis therapy.

METHODS

This was a case-control study including patients receiving anti-tuberculosis regimen. Cases (n = 23) were tuberculosis patients presenting ATDH during two months of anti-tuberculosis drug therapy. Controls (n = 30) were patients treated for tuberculosis, but presenting no ATDH. Genotyping was performed using a polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

No statistically significant association was observed between GSTM1 and GSTT1 homozygous null genotypes, and the risk of ATDH. A statistically significant association between GSTM1 and GSTT1 double null genotypes, and the risk of ATDH was found (p = 0.033) between cases and controls. For GSTP1, the distribution of GG homozygous mutant genotype was significantly associated with ATDH compared with the wild and the transition A to G (AA + AG) genotypes.

CONCLUSION

Double deletion of GSTM1 and GSTT1 may predispose to ATDH in a Tunisian population. Moreover, GSTP1 rs1695 (A > G) genotyping can predict susceptibility to developing ATDH.

Impact of Non-Alcoholic Simple Fatty Liver Disease on Antituberculosis Drug-Induced Liver Injury

Objective

To observe the effect of non-alcoholic simple fatty liver disease on drug-induced liver injury caused by tuberculosis.

Methods

We retrospectively analyzed the incidence, characteristics, and risk factors of antituberculosis drug-induced liver injury in 104 patients with initial treatment of tuberculosis complicated with non-alcoholic simple fatty liver disease. The patients were divided into two groups according to whether there was liver injury or not. The differences in age, gender, body mass index (BMI), cholesterol, and triglycerides were studied between the two groups.

Results

Among the 104 patients with initial treatment of tuberculosis complicated with non-alcoholic fatty liver disease, 24 (23%) patients developed a drug-induced liver injury. The remaining 80 (77%) patients did not develop drug-induced liver injury (χ² = 60.308, P < 0.05). In the liver injury group, there were 20 cases of mild liver injury, two cases of moderate liver injury, two cases of severe liver injury, 22 cases of hepatocellular injury, two cases of cholestasis, and no cases of mixed liver injury. The time of abnormal liver function in antituberculosis treatment was 16.42 ± 9.18 days from the beginning of the antituberculosis treatment. There were no significant differences in gender, age, BMI, or triglyceride between the liver injury group and the non-liver injury group (χ² = 2.063, t = 0.179, t = 0.703, t = 1.12, P > 0.05 in all), but there were significant differences in cholesterol (t = 3.08, P < 0.05). By logistic regression analysis, cholesterol was a high-risk factor for liver injury.

Conclusion

Non-alcoholic simple fatty liver disease may increase the risk of antituberculosis drug-induced liver injury.

Roselle (Hibiscus sabdariffa L.) calyx water extract ameliorates isoniazid and rifampicin induced liver and renal injuries in rats

Introduction: Roselle (Hibiscus sabdariffa L.) calyces possess natural antioxidants that may provide therapeutic benefits. This study aimed to investigate the protective effects of Roselle calyx water extract against isoniazid (INH) and rifampicin (RIF) induced liver and renal toxicities.Methods: Male Wistar rats (150-250 g) were designated into five groups: control group, INH-RIF group that was treated with INH-RIF at the toxic doses (50-100 mg/kg for 4 weeks, followed by 100-200 mg/kg for 2 weeks), and Roselle groups that were treated daily with Roselle extract at the doses 62.5, 125, and 250 mg/kg, respectively prior to INH-RIF administration. Blood samples were withdrawn weekly for 6 weeks before removing rats’ livers and kidneys for tissue malondialdehyde (MDA) and histopathological analysis.Results: The results showed all rats in the INH-RIF group experienced marked elevations of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea, creatinine, and tissue MDA levels compared to the controls (P<0.05). In contrast, these biomarkers were maintained at near-normal levels in Roselle extract groups. Significant inflammation and cellular degeneration were found in the liver and renal tissues of the INH-RIF group, which were noticeably reduced with Roselle extract pre-treatment at the dose of 250 mg/kg.Conclusion: It is concluded that Roselle calyx extract can provide protection against liver and renal toxicities induced by INH-RIF administration in rats.

A validation study of the UGT1A4 rs2011404 variant and the risk of anti-tuberculosis drug-induced hepatotoxicity in an Eastern Chinese Han population

WHAT IS KNOWN AND OBJECTIVE

Anti-tuberculosis (anti-TB) drug-induced hepatotoxicity (ATDH) is a serious adverse drug reaction. A recent study found that the rs2011404 variant of uridine 5'-diphospho-glucuronosyl-transferase 1A4 (UGT1A4) is a marker of susceptibility to ATDH. The present study aimed to validate this relationship in an Eastern Chinese Han anti-TB treatment population.

METHODS

A 1:4 matched case-control study was conducted among anti-TB treatment patients in four regions of Jiangsu. ATDH was diagnosed based on the criteria from the Chinese Society of Hepatology and the updated Roussel Uclaf Causality Assessment Method. A conditional logistic regression model was used to estimate the association between rs2011404 genotypes and the risk of ATDH using odds ratios (ORs) with 95% confidence intervals (95% CIs) and smoking, drinking, hepatoprotectant use and liver diseases as covariates.

RESULTS AND DISCUSSION

A total of 202 ATDH cases and 808 controls were matched according to age, sex and treatment history. After correcting for potential confounding factors, conditional logistic regression analysis indicated no significant differences in genotypes between the two groups (CC vs. TC: OR = 0.933, 95% CI: 0.457-1.905, p = 0.849). Subgroup analysis suggested that patients carrying the CC genotype at rs2011404 in UGT1A4 were at a reduced risk of moderate or severe liver injury (OR = 0.293, 95% CI: 0.093-0.921, p = 0.036).

WHAT IS NEW AND CONCLUSION

Based on a 1:4 individual matched case-control study, possessing the CC genotype at rs2011404 of the UGT1A4 gene reduces the risk of moderate or severe liver injury in Eastern Chinese Han patients receiving anti-TB treatment. Further research is warranted to explain the role of the UGT1A4 gene and its contribution to individual differences in susceptibility to ATDH.

Malnutrition prevalence and associated biochemical factors among drug-resistance tuberculosis (DR-TB) patients at key treatment sites in Conakry City, Republic of Guinea

Introduction

drug-resistant tuberculosis is a major global health problem and a threat to health security given the increase in the number of cases and the challenges associated with care. Besides, the relationship between poor nutritional status and tuberculosis is clearly established. For relevant and evidence-based public health decision-making regarding the management of malnutrition in patients with drug-resistant tuberculosis in the initial phase, it is essential to estimate the prevalence of malnutrition and understand the risk factors associated with it.

Methods

we performed a retrospective cohort study in drug-resistant tuberculosis patients aged 18 years and older, among which the nutritional status was assessed through BMI. All predictors were included in a prediction model using the multivariate logistic model according to the lowest Akaike criterion. Discrimination and model calibration was evaluated using receiver performance analysis, and the Hosmer and Lemeshow test.

Results

this study revealed a prevalence of malnutrition of 64.7% in drug-resistant tuberculosis patients in our 218-patient series. The factors associated with malnutrition were: unsuccessful treatment, the active presence of mycobacterium tuberculosis, increased bacteriological conversion time, increased serum creatinine, increased transaminase SGPT of the liver, and anaemia. Some of the factors not associated with malnutrition included the history of anti-tuberculosis treatment, vomiting, hepatic SGPT, initial AFB count, smear and culture conversion time, depression, and chest X-ray.

Conclusion

malnutrition remains a concern among drug-resistant tuberculosis patients in Guinea as it affects more than half of them with a negative impact on the outcome of treatment. Implementing specific interventions for these high-risk patients, including nutritional supplementation, psychosocial support, and treatment for tuberculosis, can improve management for better treatment outcomes.

Anti-Tuberculosis Drug Induced Hepatotoxicity and Associated Factors among Tuberculosis Patients at Selected Hospitals, Ethiopia

Background

Tuberculosis caused by susceptible mycobacterium tuberculosis strains is effectively treated by the first-line anti-tuberculosis drugs. However, most antibacterial drugs are known to induce hepatotoxicity which may limit their adherence and hence lead to the development of mycobacterial drug resistance.

Objective

The aim of this study was to assess the incidence of anti-tuberculosis drug induced hepatotoxicity and associated factors among tuberculosis patients of Debre Markos, Mota, and Bichena Hospitals.

Methods

The prospective cross sectional-study was conducted in three hospitals of East Gojjam zone by taking blood samples of new tuberculosis patients every 2 weeks for 2 months to measure the elevation of liver proteins indicating liver toxicity from the onset of starting therapy. A semi-structured questionnaire was also used to collect the socio-demographic data and factors of anti-tubeculosis drug induced liver toxicity. To identify factors associated with drug induced hepatotoxicity, binary logistic regression followed by multivariate analysis was applied at a statistically significant level of P<0.05.

Results

The incidence of hepatotoxicity among tuberculosis patients is 7.9%. Diagnosis of extrapulmonary tuberculosis, having comorbid disease, and old age are significantly associated (P<0.05) with first-line antituberculosis drugs induced hepatotoxicity.

Conclusion

The incidence of hepatotoxicity is relatively high among tuberculosis patients taking first-line anti-tuberculosis drugs. Therefore, the liver function of patients with old age, comorbid diseases, and extrapulmonary tuberculosis should be regularly monitored to reduce the severity of drug-induced hepatotoxicity.

Collagen type XVIII alpha 1 chain (COL18A1) variants affect the risk of anti-tuberculosis drug-induced hepatotoxicity: A prospective study

Background

The role of collagen type XVIII alpha 1 chain (COL18A1) in anti‐tuberculosis drug‐induced hepatotoxicity (ATDH) has not been reported. This study aimed to explore the association between of COL18A1 variants and ATDH susceptibility.

Methods

A total of 746 patients were enrolled in our study from December 2016 to April 2018, and all subjects in the study signed an informed consent form. The custom‐by‐design 2x48‐Plex SNPscanTM kit was used to genotype all selected 11 SNPs. Categorical variables were compared by chi‐square (χ²) or Fisher's exact test, while continuous variables were compared by Mann‐Whitney's U test. Plink was utilized to analyze allelic and genotypic frequencies, and genetic models. Multivariate logistic regression analyses were used to adjust potential factors. The odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were also calculated.

Results

Among patients with successfully genotyping, there were 114 cases and 612 controls. The mutant A allele of rs12483377 conferred the decreased risk of ATDH (OR = 0.13, 95%CI: 0.02–0.98, P = 0.020), and this significance still existed after adjusting age and gender (P = 0.024). The mutant homozygote AA genotype of rs12483377 was associated with decreased total protein levels (P = 0.018).

Conclusion

Our study first revealed that the A allele of COL18A1 rs12483377 was associated with the decreased risk of ATDH in the Western Chinese Han population, providing new perspective for the molecular prediction, precise diagnosis, and individual treatment of ATDH.

Alanine transaminase and hemoglobin appear to predict the occurrence of antituberculosis medication hepatotoxicity; findings and implications in Botswana

OBJECTIVE

Tuberculosis (TB) remains a global health problem, with medications having adverse effects including drug-induced hepatotoxicity. We determined the prevalence of anti-tuberculosis drug-induced hepatotoxicity and associated risk factors.

METHODS

Retrospective cross-sectional study in Botswana including TB patients admitted from 1 June 2017 to 30 June 2018. Anti-TB drug-induced hepatotoxicity was categorized according to WHO criteria whereas causality assessment was made according to the updated Roussel Uclaf Causality Assessment Method (RUCAM) scale. The association between hepatotoxicity and included variables was undertaken by binary logistic regression.

RESULTS

Out of 112 patient files, 15 (13.4%) developed hepatotoxicity after an average of 20.4 days from the start of treatment. Grade 3 and 4 hepatotoxicity was found in 66.7% of the cases. According to the updated RUCAM tool, 86.7% of patients were categorized as having possible anti-TB-associated hepatotoxicity. Patients with elevated baseline alanine transaminase (ALT) were more likely to develop hepatotoxicity (OR = 3.484, 95% CI = 1.02-11.90). Patients with normal hemoglobin (Hb ≥ 12 g/dl) were also more likely to develop hepatotoxicity (OR = 4.413, 95% CI = 1.160-14.8).

CONCLUSION

Overall, normal hemoglobin and elevated baseline ALT levels were significantly associated with anti-TB drug-induced hepatotoxicity. Additional research is needed to explore this association further.

The high incidence of severe adverse events due to pyrazinamide in elderly patients with tuberculosis

Background

Pyrazinamide (PZA) is a common drug that causes serious adverse events (SAEs). The aim of this study was to determine the incidence of and risk factors for SAEs due to PZA during first-line anti-tuberculosis treatment.

Methods

The medical records of patients with tuberculosis (TB) treated with PZA-containing regimens including first-line drugs—ethambutol, rifampicin, and isoniazid—from January 2003 to June 2016 were reviewed. SAEs were defined as side effects that led to drug discontinuation. The causative drug was determined based on the disappearance of the SAEs upon drug withdrawal and/or the recurrence of the same SAEs with re-challenge.

Results

Of 2,478 patients with TB, 16.4% experienced SAEs. The incidence of SAEs increased significantly as age increased, except with rifampin. PZA accounted for most SAEs (55.8%). Hepatotoxicity was the most common SAE due to PZA (44.5%), followed by gastrointestinal (GI) intolerance (23.8%). The risk of SAEs due to PZA increased significantly as age increased, when sex and comorbidities were adjusted (odds ratio, 1.013; 95% confidence interval, 1.004–1.023; P = 0.007). In the subgroup analysis, older age was an independent risk factor for GI intolerance but not for hepatotoxicity.

Conclusion

PZA was the most common drug associated with SAEs among the first-line anti-TB drugs, and old age was an independent factor for SAE occurrence. This study suggests that the early recognition of whether the causative agent is PZA may improve effective treatment compliance, particularly in elderly patients.

Safety and efficacy of N-acetylcysteine in hospitalized patients with HIV-associated tuberculosis: An open-label, randomized, phase II trial (RIPENACTB Study)

Despite the availability of effective antimicrobials, tuberculosis (TB) is still a serious health threat. Mortality is even higher in people living with HIV who are diagnosed with TB. New therapies are needed to shorten the time required to cure TB and decrease fatality rates in this population. N-acetylcysteine (NAC) is a glutathione precursor and has shown recently in experimental setting to present in vitro and in vivo anti-mycobacterial activity. We test the hypothesis that NAC is safe, well tolerated and secondarily efficacious as adjunctive anti-TB therapy in hospitalized individuals with HIV-associated TB. Patients were enrolled sequentially in a tertiary care center, in the Brazilian Amazon. We performed a randomized, parallel group, single-center, open study trial of two arms, in hospitalized patients over 18 years of age, with microbiologically confirmed pulmonary TB in HIV: one with rifampicin, isoniazid, pyrazinamide and ethambutol at standard doses (Control Group), and a second in which NAC 600 mg bid for eight weeks was added (NAC Group). A total of 21 and 18 patients were enrolled to the Control Group and NAC Group, respectively. Adverse event rates were similar in the two arms. Our findings suggest that in the more critical population of hospitalized patients with HIV-associated TB, the use of NAC was not unsafe, despite the low sample size, and a potential impact on faster negative cultures needs to be further explored in larger studies.

Bile acids, lipid and purine metabolism involved in hepatotoxicity of first-line anti-tuberculosis drugs

OBJECTIVES

Rifampin (RIF), isoniazid (INH) and pyrazinamide (PZA) are essential components of the short-term first-line anti-tuberculosis (anti-TB) chemotherapy regimen and can cause hepatotoxicity. However, the mechanism of anti-TB drug-induced hepatotoxicity (ATDH) is currently unclear. We investigate the relevant contributions to liver injury and the pathway of the above-mentioned drugs administered alone or in combination.

METHODS

UPLC-Q-TOF/MS-based metabolomics, bile acids (BAs) analysis and FXR/SHP detection were used to evaluate the toxicity of these drugs and clarify the underlying metabolism-related pathway.

RESULTS

In C57BL/6 mice administered the corrected clinical doses, RIF, INH and PZA could induced hepatotoxicity; with less toxicity in the combination therapy than RIF. The pathological biochemistry, BAs concentration and metabolically regulated FXR/SHP gene expression analyzes in mice were consistent with the metabolomics results. FXR played a role in the hepatotoxicity of anti-tuberculosis drugs in the obeticholic acid treated and FXR^-/- mice. Additionally, the purine and lipid metabolic pathways were involved in ATDH.

CONCLUSION

ATDH was involved in bile acids and lipid and purine metabolism. The BAs metabolic pathway involvement in mice was validated in TB patients. The noninvasive metabolomics approach is more systemic than routine toxicity evaluation and can be used to assess compound toxicity and the underlying mechanism.

The role of NAT2 polymorphism and methylation in anti-tuberculosis drug-induced liver injury in Mongolian tuberculosis patients

WHAT IS KNOWN AND OBJECTIVE

Anti-tuberculosis drug-induced liver injury (ATLI) is one of the most significant adverse reactions for this line of therapy. N-acetyltransferase 2 (NAT2) is an important metabolic enzyme involved in drug metabolism and detoxification. Genetic polymorphism and DNA methylation have been proven to be key factors that affect the expression of NAT2. Therefore, the objective of the study was to investigate the relationship between NAT2 gene polymorphism and DNA methylation in the promoter region with ATLI risk in Mongolian tuberculosis patients.

METHODS

Our study is a case-control design. Chi-square test, Mann-Whitney U non-parametric test and Pearson test were all used to analyse existing relationships. The association between NAT2 gene acetylation phenotype and the total methylation of the NAT2 promoter region was analysed by means of binary logistic regression analysis. The general situation of the patients was evaluated by questionnaire, and the NAT2 genotyping of the three major polymorphism loci of gene coding was carried out by a gene sequencing technique. The methylation status of the NAT2 gene promoter region was detected by bisulphite sequencing and mass spectrometry.

RESULT AND DISCUSSION

Our study found that the detection rate of ATLI in Mongolian tuberculosis patients was 27.6%. There were no significant differences in demographic characteristics and living habits amongst the two groups, while significant differences were observed in the polymorphism of the NAT2 genes 481 (rs1799929) and 590 (rs1799930) and the acetylation phenotype. Moreover, the composition and distribution of the NAT2*4/4 and NAT2*4/5 genotypes were found in the two groups. The risk of ATLI in the slow acetylation type was 3.56 times higher than that of the fast acetylation type. Compared with the control group, the CpG5, CpG10, CpG11.12 and total methylation of the NAT2 promoter region in the ATLI group showed a hypermethylated pattern (P < .05). However, on performing binary logistic regression, neither the slow acetylation, intermediate acetylation nor rapid acetylation were found to be associated with ATLI (P > .05). It was found that the total methylation of NAT2 gene promoter region was an independent influencing factor of ATLI in Mongolian tuberculosis patients. With the increase of the total methylation level of NAT2 gene promoter region, the risk of ATLI increased gradually. (OR = 8.371, 95% CI: 2.391 ~ 29.315). CpG1, CpG4, CpG9, CpG10 and CpG11.12 were positively correlated with a total methylation level in the ATLI group.

WHAT IS NEW AND CONCLUSION

The detection rate of ATLI in Mongolian tuberculosis patients was 27.6%, and there were differences in the NAT2 genotypes and acetylated phenotypes. The slow acetylated type was the risk factor for ATLI. Methylation in the promoter region of the NAT2 gene has an effect on the risk of ATLI. After adjusting for the interference of three acetylation types, it was found that the total methylation of the promoter region of NAT2 gene in Mongolian tuberculosis patients is an independent influencing factor of ATLI. Furthermore, there is a moderate to high correlation between some sites and the overall level of methylation.

Fact versus Fiction: a Review of the Evidence behind Alcohol and Antibiotic Interactions

Many antibiotics carry caution stickers that warn against alcohol consumption. Data regarding concurrent use are sparse. An awareness of data that address this common clinical scenario is important so health care professionals can make informed clinical decisions and address questions in an evidence-based manner. The purpose of this systematic review was to determine the evidence behind alcohol warnings issued for many common antimicrobials. The search was conducted from inception of each database to 2018 using PubMed, Medline via Ovid, and Embase. It included studies that involved interactions, effects on efficacy, and toxicity/adverse drug reactions (ADR) due to concomitant alcohol consumption and antimicrobials. All interactions were considered in terms of three components: (i) alteration in pharmacokinetics/pharmacodynamics (PK/PD) of antimicrobials and/or alcohol, (ii) change in antimicrobial efficacy, and (iii) development of toxicity/ADR. Available data support that oral penicillins, cefdinir, cefpodoxime, fluoroquinolones, azithromycin, tetracycline, nitrofurantoin, secnidazole, tinidazole, and fluconazole can be safely used with concomitant alcohol consumption. Data are equivocal for trimethoprim-sulfamethoxazole. Erythromycin may have reduced efficacy with alcohol consumption, and doxycycline may have reduced efficacy in chronic alcoholism. Alcohol low in tyramine may be consumed with oxazolidinones. The disulfiram-like reaction, though classically associated with metronidazole, occurs with uncertain frequency and with varied severity. Cephalosporins with a methylthiotetrazole (MTT) side chain or a methylthiodioxotriazine (MTDT) ring, ketoconazole, and griseofulvin have an increased risk of a disulfiram-like reaction. Alcohol and antimicrobial interactions are often lacking evidence. This review questions common beliefs due to poor, often conflicting data and identifies important knowledge gaps.

Regulation of P300 and HDAC1 on endoplasmic reticulum stress in isoniazid-induced HL-7702 hepatocyte injury

P300 and HDAC1 can be involved in the development of various liver diseases by regulating gene transcription. Endoplasmic reticulum stress (ERS) is one of the main pathways of apoptosis and is activated during inflammatory responses, but the roles of P300 and HDAC1 in ERS in antituberculosis drug-induced liver injury (ADLI) are not clear. This study confirms that isoniazid can change the states of P300 and HDAC1 in HL-7702 hepatocyte metabolism and induce ERS, causing hepatocyte injury and apoptosis. When combined with C646, however, P300 can be reduced. HL-7702 cells were flattened, and the cytoplasm became crinkled. To a certain extent, ERS was relieved, but hepatocytes suffered worse damage, and the rate of cell apoptosis markedly increased. When MS-275 was applied, HDAC1 level was increased, cell fusion appeared, and fluorescence intensity of endoplasmic reticulum was weakened. In addition, ERS was aggravated, but liver injury was relieved, and the apoptosis rate significantly decreased. Therefore, alteration of P300 and HDAC1 status and ERS are involved in ADLI, and changes in P300 and HDAC1 can regulate ERS and then affect cell damage.

The Variant at TGFBRAP1 but Not TGFBR2 Is Associated with Antituberculosis Drug-Induced Liver Injury

Background

TGFBRAP1 and TGFBR2 play important roles in the TGF-β/smad signalling pathway and may disturb liver homeostasis by regulating liver injury and renewal. However, little is known about the association between their genetic polymorphisms and antituberculosis drug-induced liver injury (ATDILI), so we explored the association between their variants and the susceptibility to ATDILI.

Materials and Methods

A total of 746 tuberculosis patients were prospectively enrolled, and fifteen selected SNPs were genotyped. The allele, genotype, and genetic model frequencies of the variants were compared between patients with or without ATDILI, as well as the joint effect analysis of SNP-SNP interactions. The odds ratio (OR) with the corresponding 95% confidence interval (CI) was calculated.

Results

The A variant at rs17687727 was significantly associated with an increased risk for ATDILI (OR 1.55; 95% CI: 1.08–2.22; p = 0.016), which is consistent with the results in the additive and dominant models. Other allele, genotype, and genetic model frequencies were similar in the two groups for the other fourteen SNPs (all p > 0.05).

Conclusion

Our study first implied that the A variant of rs17687727 in TGFBRAP1 influenced the susceptibility to ATDILI in first-line antituberculosis combination treatment in the Han Chinese population in a dependent manner.

A closer look at the spectrum of drug-induced liver injury in sub-Saharan Africa

Introduction: Drug-induced liver injury (DILI) has become the most frequent cause of acute liver failure in high-income countries. However, little is known about the determinants of DILI in sub-Saharan Africa (SSA), where the prescription of antimicrobials and the use of potentially hepatotoxic traditional medicine are common. Areas covered: Based on an extensive literature search, we summarize current data available on the epidemiology and risk factors of DILI in SSA. We discuss the most likely causes of DILI in the region, including antimicrobial therapies and traditional medicine. We also highlight research gaps as well as barriers to diagnosis and management of the condition, and explore ways to address these important challenges. Expert opinion: DILI is underestimated in SSA and several factors challenge its early diagnosis, including lack of information on the causes of DILI in the region, sub-optimal knowledge about the condition among clinicians, and structural difficulties faced by health care systems. In order to better prevent the occurrence of DILI and its complications, it is crucial to enhance awareness among health care providers and patients, adapt drug prescription habits and regulations, and improve current knowledge on the main risk factors for DILI, including host genetic and environmental determinants.

Derivatives of 3-Aminopyrazine-2-carboxamides: Synthesis, Antimicrobial Evaluation, and in Vitro Cytotoxicity

We report the design, synthesis, and in vitro antimicrobial activity of a series of N-substituted 3-aminopyrazine-2-carboxamides with free amino groups in position 3 on the pyrazine ring. Based on various substituents on the carboxamidic moiety, the series is subdivided into benzyl, alkyl, and phenyl derivatives. The three-dimensional structures of the title compounds were predicted using energy minimization and low mode molecular dynamics under AMBER10:EHT forcefield. Compounds were evaluated for antimycobacterial, antibacterial, and antifungal activities in vitro. The most active compound against Mycobacterium tuberculosis H37Rv (Mtb) was 3-amino-N-(2,4-dimethoxyphenyl)pyrazine-2-carboxamide (17, MIC = 12.5 µg/mL, 46 µM). Antimycobacterial activity against Mtb and M. kansasii along with antibacterial activity increased among the alkyl derivatives with increasing the length of carbon side chain. Antibacterial activity was observed for phenyl and alkyl derivatives, but not for benzyl derivatives. Antifungal activity was observed in all structural subtypes, mainly against Trichophyton interdigitale and Candida albicans. The four most active compounds (compounds 10, 16, 17, 20) were evaluated for their in vitro cytotoxicity in HepG2 cancer cell line; only compound 20 was found to exert some level of cytotoxicity. Compounds belonging to the current series were compared to previously published, structurally related compounds in terms of antimicrobial activity to draw structure activity relationships conclusions.

Disseminated Granulomatous Disease from Intravesical Instillation of Bacillus Calmette-Guerin

Intravesical instillation of Bacillus Calmette-Guerin is one of the standard treatment options for superficial bladder cancer. While Bacillus Calmette-Guerin therapy is usually well tolerated with most patients experiencing only cystitis, in rare cases, it can lead to disseminated granulomatous disease. We present a case of a 72-year-old man with disseminated granulomatous disease from intravesical BCG instillation whose treatment was complicated by antimycobacterial drug toxicity.

First-line anti-tuberculosis drugs induce hepatotoxicity: A novel mechanism based on a urinary metabolomics platform

Tuberculosis (TB) has become a global public health and social threat. As clinical first-line drugs, rifampicin and isoniazid used in combination with pyrazinamide and ethambutol (the HRZE regimen) usually induce hepatotoxicity. However, the mechanisms underlying this phenomenon remain unclear, and studying the metabolic impact of co-treating TB patients with the HRZE regimen can provide new hepatotoxicity evidence. In this study, urine metabolites from TB patients were profiled using a high-resolution ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) platform. The tricarboxylic acid circulation, arginine and proline metabolism and purine metabolic pathways were found to be affected by anti-TB drugs. The levels of pyroglutamate, isocitrate, citrate, and xanthine were significantly decreased after the administration of HRZE. The above mentioned pathways were also different between drug-induced liver injury (DILI) and non-DILI patients. Urate and cis-4-octenedioic acid levels in the DILI group were significantly increased compared to those in the non-DILI group, while the cis-aconitate and hypoxanthine levels were significantly decreased. These results highlight that superoxide generation can aggravate the hepatotoxic effects of the HRZE regimen. In addition, our metabolomic approach had the ability to predict hepatotoxicity for clinical applications.