Antituberculosis-Drugs Induced DRESS: A Multidrug Hypersensitivity or Drug Hypersensitivity Relapse? A Case Report

DRESS related to first-line antituberculosis drugs (ATD) is a challenging diagnosis. With a long-lasting combined treatment of 4-concomitantly administrated drugs, identification of the culprit drug remains difficult and may expose patients to treatment interruption and affect their outcome. A 42-year-old female, treated with isoniazid, rifampicin, pyrazinamide and ethambutol for multifocal tuberculosis, developed, 40 days later, hyperthermia, facial edema, cervical lymphadenopathy and generalized exanthema. Biological test results revealed eosinophilia, atypical lymphocytes, and liver injury. DRESS was suspected, and ATD were withdrawn. As patch tests for the 4 ATD showed negative results, we decided to reintroduce pyrazinamide, ethambutol and rifampicin separately with a 3-day interval. Pyrazinamide and rifampicin were tolerated. However, after receiving ethambutol, she developed fever and generalized rash, with no biological abnormalities. Since ethambutol was claimed to be the culprit drug, isoniazid was added, and 10 hours later, the patient developed fever, facial edema, generalized rash, eosinophilia and liver injury. This clinical and biological pattern resolved 2 weeks later. This report suggests a hypersensitivity relapse to ethambutol after isoniazid-induced DRESS.

In vitro optimization of crushed drug-sensitive antituberculosis medication when administered via a nasogastric tube

IMPORTANCE

The incidence of tuberculosis (TB) in intensive care units (ICUs) can be as high as 3% in high-burden settings, translating to more than 7,500 patients admitted to the ICU annually. In resource-limited settings, the lack or absence of intravenous formulations of drug-sensitive antituberculosis medications necessitates healthcare practitioners to crush, dissolve, and administer the drugs to critically ill patients via a nasogastric tube (NGT). This off-label practice has been linked to plasma concentrations below the recommended target concentrations, particularly of rifampicin and isoniazid, leading to clinical failure and the development of drug resistance. Optimizing the delivery of crushed drug-sensitive antituberculosis medication via the NGT to critically ill patients is of utmost importance.

Clinical research progress of novel antituberculosis drugs on multidrug-resistant tuberculosis

Multidrug-resistant tuberculosis (MDR-TB) has become a critical challenge to public health, and the prevention and treatment of MDR-TB are of great significance in reducing the global burden of tuberculosis. How to improve the effectiveness and safety of chemotherapy for MDR-TB is a pressing issue that needs to be addressed in tuberculosis control efforts. This article provides a comprehensive review of the clinical application of new antituberculosis drugs in MDR-TB, aiming to provide a scientific basis for the prevention and treatment strategy of MDR-TB.

Influence of sex on the exposure to isoniazid in patients with pulmonary tuberculosis

Isoniazid is a key component of tuberculosis treatment. Adequate exposure is a determinant for therapeutic success; however, considerable inter- and intraindividual variations in drug plasma levels can lead to unfavorable outcomes. While some predictors of isoniazid levels are well-known, others, such as sex, yield controversial results, requiring further investigation to optimize exposure. This study investigates whether the sex of patients influences the dose administered and the concentrations of isoniazid in plasma. Levels of isoniazid were associated with the N-acetyltransferase 2 phenotypes. A total of 76 male and 58 female patients were included. Isoniazid was measured by high-performance liquid chromatography, and N-acetyltransferase 2 phenotypes were assessed using molecular techniques. The results show that the dose administered, expressed in mg/kg, was higher in females, but the plasma levels were similar between both sexes. Among patients, 46.2%, 38.8%, and 15% were slow, intermediate, and fast acetylators, respectively. As expected, isoniazid levels were associated with the acetylation phenotypes, with higher concentrations in the slow acetylators. Thus, sex-related difference in isoniazid levels is due to the body weight of patients, and the optimized dose regimen based on patient weight and acetylator phenotypes can improve the treatment outcomes.

Case report: Successful treatment with contezolid in a patient with tuberculous meningitis who was intolerant to linezolid

Tuberculous meningitis (TBM) is the most common form of central nervous system tuberculosis (TB) and the most severe form of extrapulmonary TB. It often presents with non-specific symptoms initially and has a high mortality and disability rate. With good central nervous system penetration, linezolid is recommended for treating drug-resistant, severe, or refractory tuberculous meningitis in China. Despite the benefits of linezolid on TBM treatment, the adverse effects of long-term therapy, such as myelosuppression, peripheral neuritis, and optic neuritis, are notable and can be severe and even life-threatening, leading to discontinuation and compromising treatment expectations. Contezolid is a novel oxazolidinone antibacterial agent approved by the National Medical Products Administration of China in 2021, which has a more favorable safety profile than linezolid in terms of myelosuppression and monoamine oxidase inhibition. Here we first report a case of TBM in a patient who was intolerant to antituberculosis treatment with linezolid and achieved good efficacy and safety results after the compassionate use of contezolid. Given the widespread use of linezolid in TB treatment and the potential risks for long-term use, multi-center prospective controlled clinical trials in TB and TBM patients are needed to investigate the appropriate use of contezolid further.

Serum Protein Electrophoresis Bands As Biomarkers for Drug-Sensitive Pulmonary Tuberculosis

INTRODUCTION

India has the highest cases of tuberculosis worldwide. According to WHO (2022), the incidence of tuberculosis in India is 210 per 100,000 population. Their incidence of new positive smear cases is 75 per 100,000 population per year. In tuberculosis, the level of albumin decreases while globulin increases leading to a low albumin to globulin (A/G) ratio, and electrophoresis of serum proteins are good diagnostic approach and provides essential information for monitoring treatment outcomes.

MATERIALS AND METHODS

The present study includes 50 cases of pulmonary tuberculosis and 50 age-sex-matched healthy controls. Initially, serum protein estimation and electrophoresis were performed in newly diagnosed patients and controls. All drugs were given as National Tuberculosis Elimination Programme (NTEP) guidelines and blood samples were collected at two-month, four-month, and six-month intervals, and different serum protein fractions were compared and analyzed.

RESULTS

The total serum protein was significantly lower in the cases than in the controls; 6.12±0.61 vs. 7.02±0.56 g/dL (p˂0.0020, t-value=3.12). The mean serum albumin was also significantly lower in the cases compared to the controls; 1.65±0.69 vs. 3.87±0.47g/dL (p˂0.0001, t-value=10.98). The α1 globulin started to rise after four months of treatment and at six months level was 0.262±0.32 g/dL. The level of γ globulin continuously decreases after antituberculous treatment to 1.56±0.67 gm/dL at six months.

CONCLUSION

The cause of the decrease in total protein and albumin may be due to malnutrition leading to low cellular immunity. Serum protein level and protein electrophoresis should be analyzed as routine tests in patients before, during, and after treatment. It helps us in identifying patients at risk of pulmonary tuberculosis as well prognosis of the disease. This study is a valuable guide in deciding the effective management of tuberculosis patients with drug treatment plans and appropriate dietary intake. Hence, it highlights the complex relationship that exists between poverty and disease.

Human Serum Albumin Nanoparticles: Synthesis, Optimization and Immobilization with Antituberculosis Drugs

The aim of this study was to create nanoparticles of human serum albumin immobilized with anti-TB drugs (rifampicin, isoniazid) using the desolvation method. Central Composite Design (CCD) was applied to study the effect of albumin, urea, L-cysteine, rifampicin and isoniazid concentration on particle size, polydispersity and loading degree of the drugs. The optimized nanoparticles were spherical in shape with an average particle size of 216.7 ± 3.7 nm and polydispersity of 0.286 ± 4.9. The loading degree of rifampicin and isoniazid in the optimized nanoparticles were 44% and 27%, respectively. The obtained nanoparticles were examined by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC); the results showed the absence of drug-polymer interactions. The drug release from the polymer matrix was studied using dialysis membranes.

Analysis of serum microRNA-122 in a randomized controlled trial of N-acetylcysteine for treatment of antituberculosis drug-induced liver injury

AIM

Serum microRNA-122 (miR-122) is a novel biomarker for drug-induced liver injury, with good sensitivity in the early diagnosis of paracetamol-induced liver injury. We describe miR-122 concentrations in participants with antituberculosis drug-induced liver injury (AT-DILI). We explored the relationship between miR-122 and alanine aminotransferase (ALT) concentrations and the effect of N-acetylcysteine (NAC) on miR-122 concentrations.

METHODS

We included participants from a randomized placebo-controlled trial of intravenous NAC in AT-DILI. ALT and miR-122 concentrations were quantified before and after infusion of NAC/placebo. We assessed correlations between ALT and miR-122 concentrations and described changes in ALT and miR-122 concentrations between sampling occasions.

RESULTS

We included 45 participants; mean age (± standard deviation) 38 (±10) years, 58% female and 91% HIV positive. The median (interquartile range) time between pre- and post-infusion biomarker specimens was 68 h (47-77 h). The median pre-infusion ALT and miR-122 concentrations were 420 U/L (238-580) and 0.58 pM (0.18-1.47), respectively. Pre-infusion ALT and miR-122 concentrations were correlated (Spearman's ρ = .54, P = .0001). Median fold-changes in ALT and miR-122 concentrations between sampling were 0.56 (0.43-0.69) and 0.75 (0.23-1.53), respectively, and were similar in the NAC and placebo groups (P = .40 and P = .68 respectively).

CONCLUSIONS

miR-122 concentrations in our participants with AT-DILI were considerably higher than previously reported in healthy volunteers and in patients on antituberculosis therapy without liver injury. We did not detect an effect of NAC on miR-122 concentrations. Further research is needed to determine the utility of miR-122 in the diagnosis and management of AT-DILI.

Anaphylactic Shock After First-Line Treatment With Antituberculosis Drugs in a Patient With Lupus

Tuberculosis (TB) is still a major public health concern in Morocco. Although first-line antituberculosis drugs (ATD) are generally considered safe and effective, serious adverse events can occur. In this case report, we describe a female with pulmonary TB who experienced anaphylaxis induced by rifampicin (RFP) and pyrazinamide (PZA) during ATD therapy. Anaphylactic reactions to first-line ATD can occur and may lead to treatment discontinuation and challenges in finding effective alternative treatment options. Healthcare professionals should be aware of the potential of anaphylaxis with the use of these drugs, especially in patients with a history of lupus. Further research is needed to better understand the mechanisms underlying anaphylaxis and develop effective preventive and management strategies. A young female patient with a history of lupus and splenectomy presented with respiratory symptoms and deterioration of general condition. She was diagnosed with pulmonary tuberculosis and received first-line ATD, which caused complications including liver dysfunction and anaphylactic shock. Despite these challenges, the anaphylactic shock was successfully managed; she was put on a combination of levofloxacin, kanamycin, and ethambutol (ETB), as well as a desensitization protocol for isoniazid (INH); the patient was cured.

Case Report: DRESS Syndrome Induced by Two Antituberculosis Drugs in an 8-Year-Old Girl

DRESS syndrome is defined as drug-induced hypersensitivity syndrome with rash, eosinophilia, and systemic symptoms. This syndrome is mostly associated with anticonvulsants, antibacterial and anti-inflammatory drugs. DRESS syndrome is a rare disease and is more frequently seen in adults. We present the first case report of DRESS syndrome in an 8-year-old girl, after 3 months of treatment with isoniazid and rifampicin. After discontinuation of drugs and a short course of prednisolone the girl recovered. After 5 years of follow-up, she is healthy and has no complaints but patch tests with isoniazid and rifampicin remain positive. The reported case emphasizes the importance of thorough medical history and including drug reactions in differential diagnosis.

Overcoming the Prokaryote/Eukaryote Barrier in Tuberculosis Treatment: A Prospect for the Repurposing and Use of Antiparasitic Drugs

Antimicrobial resistance, the so-called silent pandemic, is pushing industry and academia to find novel antimicrobial agents with new mechanisms of action in order to be active against susceptible and drug-resistant microorganisms. In the case of tuberculosis, the need of novel anti-tuberculosis drugs is specially challenging because of the intricate biology of its causative agent, Mycobacterium tuberculosis. The repurposing of medicines has arisen in recent years as a fast, low-cost, and efficient strategy to identify novel biomedical applications for already approved drugs. This review is focused on anti-parasitic drugs that have additionally demonstrated certain levels of anti-tuberculosis activity; along with this, natural products with a dual activity against parasites and against M. tuberculosis are discussed. A few clinical trials have tested antiparasitic drugs in tuberculosis patients, and have revealed effective dose and toxicity issues, which is consistent with the natural differences between tuberculosis and parasitic infections. However, through medicinal chemistry approaches, derivatives of drugs with anti-parasitic activity have become successful drugs for use in tuberculosis therapy. In summary, even when the repurposing of anti-parasitic drugs for tuberculosis treatment does not seem to be an easy job, it deserves attention as a potential contributor to fuel the anti-tuberculosis drug pipeline.

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.

Pharmacokinetics of first-line drugs in children with tuberculosis using WHO-recommended weight band doses and formulations

Background

Dispersible pediatric fixed-dose combination (FDC) tablets delivering higher doses of first-line antituberculosis drugs in World Health Organization–recommended weight bands were introduced in 2015. We report the first pharmacokinetic data for these FDC tablets in Zambian and South African children in the treatment-shortening SHINE trial.

Methods

Children weighing 4.0–7.9, 8.0–11.9, 12.0–15.9, or 16.0–24.9 kg received 1, 2, 3, or 4 tablets daily, respectively (rifampicin/isoniazid/pyrazinamide [75/50/150 mg], with or without 100 mg ethambutol, or rifampicin/isoniazid [75/50 mg]). Children 25.0–36.9 kg received doses recommended for adults <37 kg (300, 150, 800, and 550 mg/d, respectively, for rifampicin, isoniazid, pyrazinamide, and ethambutol). Pharmacokinetics were evaluated after at least 2 weeks of treatment.

Results

In the 77 children evaluated, the median age (interquartile range) was 3.7 (1.4–6.6) years; 40 (52%) were male and 20 (26%) were human immunodeficiency virus positive. The median area under the concentration-time curve from 0 to 24 hours for rifampicin, isoniazid, pyrazinamide, and ethambutol was 32.5 (interquartile range, 20.1–45.1), 16.7 (9.2–25.9), 317 (263–399), and 9.5 (7.5–11.5) mg⋅h/L, respectively, and lower in children than in adults for rifampicin in the 4.0–7.9-, 8–11.9-, and ≥25-kg weight bands, isoniazid in the 4.0–7.9-kg and ≥25-kg weight bands, and ethambutol in all 5 weight bands. Pyrazinamide exposures were similar to those in adults.

Conclusions

Recommended weight band–based FDC doses result in lower drug exposures in children in lower weight bands and in those ≥25 kg (receiving adult doses). Further adjustments to current doses are needed to match current target exposures in adults. The use of ethambutol at the current World Health Organization–recommended doses requires further evaluation.

Biological In Vitro Evaluation of PIL Graft Conjugates: Cytotoxicity Characteristics

In vitro cytotoxicity of polymer-carriers, which in the side chains contain the cholinum ionic liquid units with chloride (Cl) or pharmaceutical anions dedicated for antituberculosis therapy, i.e., p-aminosalicylate (PAS) and clavulanate (CLV), was investigated. The carriers and drug conjugates were examined, in the concentration range of 3.125-100 μg/mL, against human bronchial epithelial cells (BEAS-2B) and adenocarcinomic human alveolar basal epithelial cells (A549) as an experimental model cancer cell line possibly coexisting in tuberculosis. The cytotoxicity was evaluated by MTT test and confluency index, as well as by the cytometric analyses, including Annexin-V FITC apoptosis assay. The polymer systems showed supporting activity towards the normal cells and no tumor progress, especially at the highest concentration (100 μg/mL). The analysis of cell death did not show meaningful changes in the case of the BEAS-2B, whereas in the A549 cell line, the cytostatic activity was observed, especially for the drug-free carriers, causing death in up to 80% of cells. This can be regulated by the polymer structure, including the content of cationic units, side-chain length and density, as well as the type and content of pharmaceutical anions. The results of MTT tests, confluency, as well as cytometric analyses, distinguished the polymer systems with Cl/PAS/CLV containing 26% of grafting degree and 43% of ionic units or 46% of grafting degree and 18% of ionic units as the optimal systems.

Population Pharmacokinetic Properties of Antituberculosis Drugs in Vietnamese Children with Tuberculous Meningitis

Optimal dosing of children with tuberculous meningitis (TBM) remains uncertain and is currently based on the treatment of pulmonary tuberculosis in adults. This study aimed to investigate the population pharmacokinetics of isoniazid, rifampin, pyrazinamide, and ethambutol in Vietnamese children with TBM, to propose optimal dosing in these patients, and to determine the relationship between drug exposure and treatment outcome. A total of 100 Vietnamese children with TBM were treated with an 8-month antituberculosis regimen.

Optimal dosing of children with tuberculous meningitis (TBM) remains uncertain and is currently based on the treatment of pulmonary tuberculosis in adults. This study aimed to investigate the population pharmacokinetics of isoniazid, rifampin, pyrazinamide, and ethambutol in Vietnamese children with TBM, to propose optimal dosing in these patients, and to determine the relationship between drug exposure and treatment outcome. A total of 100 Vietnamese children with TBM were treated with an 8-month antituberculosis regimen. Nonlinear mixed-effects modeling was used to evaluate the pharmacokinetic properties of the four drugs and to simulate different dosing strategies. The pharmacokinetic properties of rifampin and pyrazinamide in plasma were described successfully by one-compartment disposition models, while those of isoniazid and ethambutol in plasma were described by two-compartment disposition models. All drug models included allometric scaling of body weight and enzyme maturation during the first years of life. Cerebrospinal fluid (CSF) penetration of rifampin was relatively poor and increased with increasing protein levels in CSF, a marker of CSF inflammation. Isoniazid and pyrazinamide showed good CSF penetration. Currently recommended doses of isoniazid and pyrazinamide, but not ethambutol and rifampin, were sufficient to achieve target exposures. The ethambutol dose cannot be increased because of ocular toxicity. Simulation results suggested that rifampin dosing at 50 mg/kg of body weight/day would be required to achieve the target exposure. Moreover, low rifampin plasma exposure was associated with an increased risk of neurological disability. Therefore, higher doses of rifampin could be considered, but further studies are needed to establish the safety and efficacy of increased dosing.

Thromboembolic complications associated with tuberculosis: A pediatric case report

La tuberculosis es una de las enfermedades infecciosas más comunes en el mundo. Aunque la mortalidad en niños es prácticamente nula cuando el diagnóstico y el tratamiento son oportunos, puede asociarse con complicaciones como la trombosis venosa profunda y la superficial a partir de la respuesta inflamatoria sistémica frente a la infección, lo que propicia la coagulación y ocasiona una significativa morbimortalidad.

Se reporta el caso de una adolescente de 14 años con tuberculosis pulmonar en tratamiento combinado quien, de forma atípica, presentó dos episodios de tromboembolia venosa: el primero en el riñón y el segundo en los pulmones. Tras descartar el síndrome nefrótico y el antifosfolipídico, los estudios de tomografía de tórax y abdomen fueron una herramienta fundamental para su diagnóstico. Se inició tratamiento con heparina de bajo peso molecular con mejoría de los síntomas. Teniendo en cuenta las necesidades de anticoagulación no fue posible realizar estudios adicionales de ampliación.

Las complicaciones tromboembólicas en pacientes con tuberculosis y sin otros factores de riesgo obligan a considerar el efecto coagulante que resulta de la reacción inflamatoria sistémica, la cual podría, por sí sola, ser la causa de una complicación significativa pero prevenible, aunque frecuentemente escapa al diagnóstico. En este sentido, se recomienda considerar la posibilidad de la tromboembolia venosa en estos pacientes y hacer un seguimiento estricto que permita aplicar el tratamiento anticoagulante tempranamente y prevenir, así, resultados adversos.

Drug exposure of first-line anti-tuberculosis drugs in China: A prospective pharmacological cohort study

AIM

Exploring the need for optimization of drug exposure to improve tuberculosis (TB) treatment outcome is of great importance. We aimed to describe drug exposure at steady state as well as the population pharmacokinetics (PK) of rifampicin (RIF), isoniazid (INH) and pyrazinamide (PZA) in Chinese TB patients.

METHODS

A prospective multicentre PK study of RIF, INH and PZA was conducted in China between January 2015 and December 2017. Six blood samples were collected from each subject for drug concentration measurement. Nonlinear mixed effect analyses were used to develop population PK models.

RESULTS

In total, 217 patients were included. Positive correlations between body weight, clearance and volume of distribution were identified for RIF and PZA, whereas body weight only influenced clearance for INH. In addition, males had higher RIF clearance and thus lower RIF exposure than women. Acetylator status was significantly associated with INH clearance as INH exposure in intermediate and fast acetylators was significantly lower than in slow acetylators, especially in low-weight bands. Simulations also showed significantly lower drug exposures in low-weight bands for all three drugs. Patients weighing <38 kg were respectively exposed to 30.4%, 45.9% and 18.0% lower area under the concentration-time curve of RIF, INH and PZA than those weighing ≥70 kg. Higher doses by addition of one fixed-dose combination tablet or 150 mg INH were simulated and found to be effective in improving INH drug exposures, especially in low-weight bands.

CONCLUSION

PK variability of first-line anti-TB drugs is common in Chinese TB patients. The developed population PK models can be used to optimize drug exposures in Chinese patients. Moreover, standard dosing needs to be adjusted to increase target attainment.

Clinical effect of vitamin D supplementation on patients with pulmonary tuberculosis and its influence on the expression of immune cells and inflammatory factors

Tuberculosis is highly infectious and has a high incidence worldwide. Therefore, effective treatment is essential for the disease. The immune function and inflammatory factors can reflect the therapeutic effect of pulmonary tuberculosis to some extent. Thus, the aim of the present study was to investigate the clinical effect of vitamin D supplementation on pulmonary tuberculosis patients and its influence on the expression of immune cells and inflammatory factors in patients. A total of 256 patients with pulmonary tuberculosis who were admitted to our hospital were collected as research participants; 120 patients who were treated with conventional antituberculosis drugs were taken as a control group (CG) and 136 patients who were treated with vitamin D-assisted antituberculosis drugs were taken as the research group (RG). The levels of inflammatory factors (IL-6, MMP-9, IL-4, TNF-α) and T lymphocyte subgroup of patients were measured in both groups before and after treatment. The efficacy was compared in both groups. The disappearance time of wheezing and cough in RG was shorter than that in CG (P<0.001). There was no difference in X-ray chest plain film, sputum examination results and efficacy of patients in both groups (P>0.05). After treatment, CD3⁺, CD4⁺, CD4⁺/CD8⁺ were upregulated in both groups (P<0.05), while CD3⁺, CD4⁺, CD4⁺/CD8⁺ in RG were higher than those in CG (P<0.05). After treatment, inflammatory factors in both groups improved compared with those before treatment. Serum inflammatory factors in RG were significantly lower than those in CG (P<0.05). After treatment, surfactant protein in the two groups was lower than that before treatment, while that in RG was significantly lower than that in CG (P<0.05). After treatment, soluble selectins in both groups improved significantly. The level of soluble selectins in RG was slightly lower than that in CG. The incidence of adverse reactions in RG was lower than that in CG. The life quality scores of patients in RG were slightly higher than those in CG (P<0.05). In conclusion, vitamin D-assisted antituberculosis drugs can effectively improve the immune function and expression level of inflammatory factors in pulmonary tuberculosis patients and reduce adverse reactions.

Mycobacterium tuberculosis β-Carbonic Anhydrases: Novel Targets for Developing Antituberculosis Drugs

The genome of Mycobacterium tuberculosis (Mtb) encodes three β-carbonic anhydrases (CAs, EC 4.2.1.1) that are crucial for the life cycle of the bacterium. The Mtbβ-CAs have been cloned and characterized, and the catalytic activities of the enzymes have been studied. The crystal structures of two of the enzymes have been resolved. In vitro inhibition studies have been conducted using different classes of carbonic anhydrase inhibitors (CAIs). In vivo inhibition studies of pathogenic bacteria containing β-CAs showed that β-CA inhibitors effectively inhibited the growth of pathogenic bacteria. The in vitro and in vivo studies clearly demonstrated that β-CAs of not only mycobacterial species, but also other pathogenic bacteria, can be targeted for developing novel antimycobacterial agents for treating tuberculosis and other microbial infections that are resistant to existing drugs. In this review, we present the molecular and structural data on three β-CAs of Mtb that will give us better insights into the roles of these enzymes in pathogenic bacterial species. We also present data from both in vitro inhibition studies using different classes of chemical compounds and in vivo inhibition studies focusing on M. marinum, a model organism and close relative of Mtb.

Pharmacokinetic study of isoniazid and pyrazinamide in children: impact of age and nutritional status

OBJECTIVES

To evaluate pharmacokinetics of first-line antitubercular drugs, isoniazid (INH) and pyrazinamide (PZA), with revised WHO dosages and to assess its adequacy in relation to age and nutritional status.

DESIGN

Observational study.

SETTING

This study was conducted at Sarojini Naidu Medical College, Agra, and National Institute for Research in Tuberculosis, Chennai.

PATIENTS

40 subjects diagnosed with tuberculosis were registered in the study and started on daily first-line antitubercular regimen based on the revised WHO guidelines.

INTERVENTIONS

Blood samples were collected at 0, 2, 4, 6 and 8 hours from these subjects after 15 days of treatment for drug estimations.

MAIN OUTCOME MEASURE

The measurement of drug concentrations (maximum peak concentration (C_max) and area under the time -concentration curve (AUC_{0-8 hours})) for INH and PZA. Appropriate statistical methods were used to evaluate the impact of age and nutritional status on pharmacokinetic variables.

RESULTS

For INH, the difference in drug exposures in children <3 years (C_max 3.18 µg/mL and AUC_{0-8 hours}15.76 µg/mL hour) and children >3 years (C_max3.05 µg/mL and AUC_{0-8 hours} 14.37 µg/mL hour) was not significant (P=0.94, P=0.81, respectively). The drug levels in children with low body mass index (BMI) (C_max3.08 µg/mL; AUC_{0-8 hours}14.81 µg/mL hour) were also comparable with their normal counterparts (C_max3.09 µg/mL, P=0.99; AUC_{0-8 hours} 14.69 µg/mL hour, P=0.82). PZA drug exposures obtained in children less than 3 years (C_max29.22 µg/mL, AUC_{0-8 hours} 155.45 µg/mL hour) were significantly lower compared with drug levels in children above 3 years (C_max 37.12 µg/mL, P=0.03; AUC 202.63 µg/mL hour, P value=0.01). Children with low BMI had significantly lower drug concentrations (C_max 31.90 µg/mL, AUC_{0-8 hours}167.64 µg/mL hour) when compared with normal counterparts (C_max 37.60 µg/mL, P=0.02; AUC_{0-8 hours} 208.77 µg/mL hour, P=0.01).

CONCLUSIONS

The revised WHO drug dosages were found to be adequate for INH with respect to age and nutritional status, whereas PZA showed significantly lower drug levels in children <3 years and in malnourished children.

Structural characterization of free-state and product-state Mycobacterium tuberculosis methionyl-tRNA synthetase reveals an induced-fit ligand-recognition mechanism

Mycobacterium tuberculosis (MTB) caused 10.4 million cases of tuberculosis and 1.7 million deaths in 2016. The incidence of multidrug-resistant and extensively drug-resistant MTB is becoming an increasing threat to public health and the development of novel anti-MTB drugs is urgently needed. Methionyl-tRNA synthetase (MetRS) is considered to be a valuable drug target. However, structural characterization of M. tuberculosis MetRS (MtMetRS) was lacking for decades, thus hampering drug design. Here, two high-resolution crystal structures of MtMetRS are reported: the free-state structure (apo form; 1.9 Å resolution) and a structure with the intermediate product methionyl-adenylate (Met-AMP) bound (2.4 Å resolution). It was found that free-state MtMetRS adopts a previously unseen conformation that has never been observed in other MetRS homologues. The pockets for methionine and AMP are not formed in free-state MtMetRS, suggesting that it is in a nonproductive conformation. Combining these findings suggests that MtMetRS employs an induced-fit mechanism in ligand binding. By comparison with the structure of human cytosolic MetRS, additional pockets specific to MtMetRS that could be used for anti-MTB drug design were located.

First-line antituberculosis drugs disrupt endocrine balance and induce ovarian and uterine oxidative stress in rats

BACKGROUND

The first-line antituberculosis (anti-TB) drugs, isoniazid (INH), rifampicin (RIF), ethambutol (EMB), and pyrazinamide (PZA), are effective in the treatment of pulmonary tuberculosis. However, the toxicity of these drugs in the clinical setting limits their use. Here, we evaluated the effects of anti-TB drugs on the reproductive system in female rats.

METHODS

Thirty-five female Wistar rats were assigned into five groups of seven animals each. The control group received normal saline, whereas others received INH (5 mg/kg), RIF (10 mg/kg), EMB (15 mg/kg), and PZA (15 mg/kg) through gavage thrice a week for 8 consecutive weeks.

RESULTS

Administration of anti-TB drugs significantly (p<0.05) reduced uterine and ovarian weight, as well as the relative weight of the uterus when compared with controls. In addition, anti-TB drugs increased the activities of alanine aminotransferase as well as the level of total bilirubin. Treatment with INH, RIF, and PZA significantly (p<0.05) reduced the levels of follicle-stimulating and luteinizing hormones, estrogen, and prolactin. The INH, RIF, EMB, and PZA caused significant (p<0.05) increases in uterine malondialdehyde (MDA) levels by 281%, 214%, 273% and 190%, respectively, whereas INH and EMB increased the ovarian malondialdehyde by 111% and 129%, respectively. These drugs significantly (p<0.05) decreased the activities of ovarian glutathione-S-transferase and uterine glutathione peroxidase, superoxide dismutase, and catalase. Histology revealed the erosion of uterine mucosa, debris in the lumen of the uterus, congestion, and underdeveloped follicles in ovaries.

CONCLUSIONS

The first-line anti-TB drugs elicited reproductive toxicity in the uterus and ovaries of rats through mechanisms that involved oxidative stress.

[Analyze of the performance of procurement and distribution system of antiretroviral, antituberculosis and antimalarials drugs in Benin in 2016]

OBJECTIVE

We aimed to analyze the performance of procurement and distribution system of antiretroviral, antituberculosis and antimalarial drugs in Benin.

METHODS

We carried out a cross-sectional study in 2016. Data on the procurement, storage and distribution of drugs were collected by either individual interview or observation of storage sites at the central procurement center for essential medicines (CAME) in Benin. Compliance with the norms of the procurement and distribution of the products was appreciated. At the operational level, order satisfaction, drug expiry and stock status of the targeted health programs were measured based on the participants statements.

RESULTS

Three workers of the CAME and 76 of health programs were surveyed. According to the norms, malfunctioning impaired the system of the procurement, storage and the distribution of the products. At the operational level, our study participants reported that antiretroviral drug orders were satisfied in 83%, drugs were distributed within three months of their expiration date in 26- 33%, and the CAME often ran out of antiretroviral drugs (stock-outs)in 69%.

CONCLUSION

Malfunctioning impaired the system of the procurement, storage and the distribution of antiretroviral, antimalarial and antituberculosis drugs. These dysfunctions negatively affect the performance of the system.

[DRESS syndrome secondary to antituberculosis drugs: about a case]

Drug hypersensitivity syndrome or Drug Rash with Eosinophilia and Systemic Symptoms or DRESS syndrome is a severe and potentially life-threatening toxidermia. It should be suspected in patients developing cutaneous reaction following drug intake. We report the case of a 45-year old patient treated for pulmonary tuberculosis (TPM+) who developed DRESS syndrom induced by antibacillaries.

National strategy for the integration of pharmacovigilance in the Moroccan TB Control Program

The objective of this work is to demonstrate the interest of integration of pharmacovigilance in Moroccan Tuberculosis Control Program (MTCP). The integration of pharmacovigilance in MTCP was conducted in October 2012with the Global Fund support. We compared the reports notified before and after this integration (period 1: January 2010-October2012; period 2: October 2012-December 2013). The detection of signals was based on the Information Component available inVigiMine. We used the SPSS version 10.0 and Med Calc version 7.3 for data analysis. The average number of spontaneous reports increased from 3.6 to 37.4 cases/month (P< 10^-3). The average age was 40.7 ± 17.5 years; the sex ratio was 0.8. Hepatic reactions (32.7%) predominated during the first period, while skin reactions (24.1%) were in the second period (P = 10^-4), and40.9% of cases in the first period were serious against 15.8% in second period (P = 0.003). Nine signals were generated (hepaticenzyme increase, cholestasis, jaundice, arthralgia, acne, lower limb edema, pruritus, skin rashes, and vomiting). The integration of pharmacovigilance in Moroccan Tuberculosis Control Program improved the management of ADRs and detected new signals of antituberculosis drugs.

Naphthalimides Selectively Inhibit the Activity of Bacterial, Replicative DNA Ligases and Display Bactericidal Effects against Tubercle Bacilli

The DNA ligases, enzymes that seal breaks in the backbones of DNA, are essential for all organisms, however bacterial ligases essential for DNA replication use β-nicotinamide adenine dinucleotide as their co-factor, whereas those that are essential in eukaryotes and viruses use adenosine-5'-triphosphate. This fact leads to the conclusion that NAD⁺-dependent DNA ligases in bacteria could be targeted by their co-factor specific inhibitors. The development of novel alternative medical strategies, including new drugs, are a top priority focus areas for tuberculosis research due to an increase in the number of multi-drug resistant as well as totally drug resistant tubercle bacilli strains. Here, through the use of a virtual high-throughput screen and manual inspection of the top 200 records, 23 compounds were selected for in vitro studies. The selected compounds were evaluated in respect to their Mycobacterium tuberculosis NAD⁺ DNA ligase inhibitory effect by a newly developed assay based on Genetic Analyzer 3500 Sequencer. The most effective agents (e.g., pinafide, mitonafide) inhibited the activity of M. tuberculosis NAD⁺-dependent DNA ligase A at concentrations of 50 µM. At the same time, the ATP-dependent (phage) DNA LigT₄ was unaffected by the agents at concentrations up to 2 mM. The selected compounds appeared to also be active against actively growing tubercle bacilli in concentrations as low as 15 µM.

Adverse effects of oral second-line antituberculosis drugs in children

INTRODUCTION

Increasing numbers of children with drug-resistant tuberculosis are accessing second-line antituberculosis drugs; these are more toxic than first-line drugs. Little is known about the safety of new antituberculosis drugs in children. Knowledge of adverse effects, and how to assess and manage these, is important to ensure good adherence and treatment outcomes.

AREAS COVERED

A Pubmed search was performed to identify articles addressing adverse effects of second-line antituberculosis drugs; a general search was done for the new drugs delamanid and bedaquiline. This review discusses adverse effects associated with oral second-line antituberculosis drugs. The spectrum of adverse effects caused by antituberculosis drugs is wide; the majority are mild or moderate, but these are important to manage as it could lead to non-adherence to treatment. Adverse effects may be more common in HIV-infected than in HIV-uninfected children.

EXPERT OPINION

Although children may experience fewer adverse effects from oral second-line antituberculosis drugs than adults, evidence from prospective studies of the incidence of adverse events in children is limited. Higher doses of second-line drugs, new antituberculosis drugs, and new drug regimens are being evaluated in children: these call for strict pharmacovigilance in children treated in the near future, as adverse effect profiles may change.

The value of eosinophil VCS parameters in predicting hepatotoxicity of antituberculosis drugs

INTRODUCTION

Drug-induced liver injury (DILI) is the most frequent cause of discontinuation of antituberculosis medication and difficult to predict. In recent years, liver eosinophilia has been associated with incidence of DILI. We hypothesize that morphologic changes in reactive eosinophils associated with DILI may be determined by LH750 (Beckman Coulter, Fullerton, CA) with VCS technology.

METHODS

The absolute eosinophil (AEC), percentage of eosinophil (EOSI%), VCS parameters, and standard deviation (SD) of 500 health controls, 376 patients without DILI, and 50 DILI patients were compared in terms of diagnostic sensitivity and specificity for DILI.

RESULTS

In DILI patients, the increased mean eosinophil volume (MEV) and size variability (MEV-SD) were observed prior to alanine aminotransferase (ALT) elevations. The MEV was correlated well with ALT after therapy. The ROC curve analyses revealed that the MEV and MEV-SD had larger areas under curves (0.894, 0.815, in the week prior to DILI) compared to other parameters. Using a cutoff of 163.15 fL for the MEV and a cutoff of 17.11 for MEV-SD, the sensitivities of 81% and 72% and specificities of 82% and 80% were achieved, respectively, which are higher than other parameters prior to DILI occurred.

CONCLUSIONS

The MEV with size variability (MEV-SD) is a quantitative, objective, and more sensitive parameter and has a potential to be an additional indicator for DILI.

Medication errors with antituberculosis therapy in an inpatient, academic setting: forgotten but not gone

WHAT IS KNOWN AND OBJECTIVE

Tuberculosis, an infectious disease caused by the bacteria Mycobacterium tuberculosis, has significant public health implications. Despite the decreasing prevalence of tuberculosis cases and the availability of well-established treatment guidelines, errors with antituberculosis medications remain a concern as clinician experience with the infection has waned and the goal of eradicating tuberculosis has remained unfulfilled. Whereas inappropriate use of other anti-infective classes has been extensively studied, the evaluation of medication errors associated with antituberculosis therapy has been limited to a small number of studies conducted more than two decades ago. This study evaluated the prevalence of inpatient medication errors with antituberculosis therapy in patients with suspected or confirmed tuberculosis disease.

METHODS

All admitted patients treated with at least one antituberculosis medication between July 2010 and June 2013 were evaluated for inclusion in the retrospective study. Multidrug antituberculosis regimens were reviewed for medication errors, which were categorized as dosing errors, drug interactions, omission of therapy and inappropriate continuation of therapy in the presence of drug toxicity. Appropriate management was determined in accordance with the national guidelines for the treatment of tuberculosis, as well as guidelines on the use of antiretroviral agents for patients with both human immunodeficiency virus (HIV) infection and tuberculosis disease. The impact of infectious diseases and pulmonary consultation on the prevalence of medication errors was also examined.

RESULTS AND DISCUSSION

More than half of all study patients (44/72, 61%) experienced at least one medication error associated with antituberculosis therapy. Dosing errors were the most common type of medication error identified and were predominantly related to weight-based dosing. Seven dosing errors were related to drug interactions between rifamycins and antiretroviral therapy in HIV-infected patients. Medication error rates were similar between patients receiving consultation from infectious diseases and/or pulmonary specialties and those without consultation. The large majority of antituberculosis medication errors (56/66 errors, 85%) remained uncorrected during the patient's hospital admission.

WHAT IS NEW AND CONCLUSION

Medication errors associated with antituberculosis therapy remain a common occurrence in the current clinical practice setting. Greater vigilance when prescribing medications for tuberculosis disease is needed.

Polymorphism of PXR gene associated with the increased risk of drug-induced liver injury in Indonesian pulmonary tuberculosis patients

WHAT IS KNOWN AND OBJECTIVE

Tuberculosis is still a major infectious disease in Indonesia. Patients are treated mostly using fixed-dose combination treatment in primary public health facilities. The incidence of antituberculosis drug-induced liver injury (AT-DILI) is approximately 10% among Indonesian tuberculosis patients who used standard fixed combination regimens during the intensive phase of treatment. However, information regarding genetic polymorphism associated with the increase risk of drug-induced liver injury is still limited. The aim of this study was to investigate pregnane X receptor (PXR) gene polymorphisms as one of the risk factors of AT-DILI.

METHODS

In this prospective cohort study, we recruited 106 adult patients diagnosed with pulmonary tuberculosis and treated with category I FDC (fixed-dose combination). The identification of SNP -25385C>T (rs3814055) was conducted by ARMS (amplification refractory mutation system). Hepatotoxicity was defined as ALT and/or AST levels above the normal threshold on the second, fourth and sixth months of monitoring during tuberculosis treatment.

RESULTS AND DISCUSSION

The logistic regression analysis showed that patients with the TT genotype of PXR gene (rs3814055) significantly had a greater risk of AT-DILI (OR 8·89; 95% CI 1·36-57·93, P < 0·05), compared with those of wild-type CC genotype.

WHAT IS NEW AND CONCLUSION

The result suggests that in Indonesian patients with tuberculosis, the risk of having AT-DILI was associated with TT genotype of the PXR gene.

Diagnosis and management of miliary tuberculosis: current state and future perspectives

Tuberculosis (TB) remains one of the most important causes of death from an infectious disease, and it poses formidable challenges to global health at the public health, scientific, and political level. Miliary TB is a potentially fatal form of TB that results from massive lymphohematogenous dissemination of Mycobacterium tuberculosis bacilli. The epidemiology of miliary TB has been altered by the emergence of the human immunodeficiency virus (HIV) infection and widespread use of immunosuppressive drugs. Diagnosis of miliary TB is a challenge that can perplex even the most experienced clinicians. There are nonspecific clinical symptoms, and the chest radiographs do not always reveal classical miliary changes. Atypical presentations like cryptic miliary TB and acute respiratory distress syndrome often lead to delayed diagnosis. High-resolution computed tomography (HRCT) is relatively more sensitive and shows randomly distributed miliary nodules. In extrapulmonary locations, ultrasonography, CT, and magnetic resonance imaging are useful in discerning the extent of organ involvement by lesions of miliary TB. Recently, positron-emission tomographic CT has been investigated as a promising tool for evaluation of suspected TB. Fundus examination for choroid tubercles, histopathological examination of tissue biopsy specimens, and rapid culture methods for isolation of M. tuberculosis in sputum, body fluids, and other body tissues aid in confirming the diagnosis. Several novel diagnostic tests have recently become available for detecting active TB disease, screening for latent M. tuberculosis infection, and identifying drug-resistant strains of M. tuberculosis. However, progress toward a robust point-of-care test has been limited, and novel biomarker discovery remains challenging. A high index of clinical suspicion and early diagnosis and timely institution of antituberculosis treatment can be lifesaving. Response to first-line antituberculosis drugs is good, but drug-induced hepatotoxicity and drug-drug interactions in HIV/TB coinfected patients create significant problems during treatment. Data available from randomized controlled trials are insufficient to define the optimum regimen and duration of treatment in patients with drug-sensitive as well as drug-resistant miliary TB, including those with HIV/AIDS, and the role of adjunctive corticosteroid treatment has not been properly studied. Research is going on worldwide in an attempt to provide a more effective vaccine than bacille Calmette-Guérin. This review highlights the epidemiology and clinical manifestation of miliary TB, challenges, recent advances, needs, and opportunities related to TB diagnostics and treatment.

Damage of testicular cell macromolecules and reproductive capacity of male rats following co-administration of ethambutol, rifampicin, isoniazid and pyrazinamide

The necessity to minimize adverse effects of tuberculosis chemotherapy requires a comprehensive evaluation of the effects of antituberculosis drugs on the reproductive system and testicular cell macromolecules. The epidemiological situation of tuberculosis in Central and Eastern Europe is getting worse. Data on adverse effects of antituberculosis drugs are scare concerning particularly their effects on the reproductive system. The aim of the present study was to investigate the potential effect of ethambutol, rifampicin, isoniazid and pyrazinamide co-administration on lipid peroxidation, glutathione content and protein SH-groups, DNA fragmentation levels, the reproductive capacity of Wistar male rats and the antenatal development of their posterity. The rats (150-170 g) were divided into two groups: group I - received antituberculosis drugs suspended in 1% starch gel per os: ethambutol - 155 mg/kg b.w./day, rifampicin - 74.4 mg/kg b.w./day, isoniazid - 62 mg/kg b.w./day, pyrazinamide - 217 mg/kg b.w./day, group II (control) - received only starch gel in corresponding volumes. The contents of TBA-active compounds, glutathione and protein SH-groups in testis and sperm were determined spectrophotometrically, the DNA-fragmentation was determined using an UV transilluminator (BIORAD, USA), reproductive system indices were measured by standard methods. The co-administration of therapeutic doses of ethambutol, isoniazid, rifampicin and pyrazinamide to male rats during the period of spermatogenesis caused an increase in the rate of thiobarbituric acid reactive substances formation in testis and sperm, decrease of testis glutathione and protein SH-group contents, significant changes in DNA fragmentation, fatal decrease of male fertilizing capacity and fertility, and increase of pre- and post-implantation embryo lethality. The changes in reproductive indices could be the result of direct or indirect effects of one or more drugs investigated.

A decision tree for rapid quality assurance and control of rifampicin-containing oral dosage forms for global distribution for tuberculosis treatment

For centuries tuberculosis remained as a complex socioeconomic problem impeding human development. Directly observed treatment short-course and fixed dose combinations were implemented in tuberculosis therapy for maximum success of treatment. However, drug shortages primarily hindered the expansion of directly observed treatment short-course, which lead to development of the global tuberculosis drug facility. Since large geographical area is covered by the global tuberculosis drug facility for global drug supply for tuberculosis eradication programs, a rapid quality control and assurance has become necessary to ensure the quality and performance of supplied antituberculosis drugs. In this manuscript a decision tree is proposed for facilitating rapid quality control (in vitro and in vivo) of antituberculosis formulations procured by the global tuberculosis drug facility. This decision tree also predicted to be applicable at every stages of anti tuberculosis drug product development, especially in identification of poor quality products and monitoring batch-to-batch variability. Further, it provides opportunity for effective quality control in resource poor settings and the gained knowledge is anticipated to be applicable for development and evaluation of antimalarial and antiAIDS fixed dose combinations.