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

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

The Magnificent Seven: Seven good publications in infectious disease

The world of infectious diseases, for various reasons, before and after the COVID-19 pandemic, capture the attention of the scientific community, either due to the epidemiological data of various microbial agents that are emerging, due to the implementation with successful results of new diagnostic strategies or due to the appearance of new therapeutic options, which encourage healthcare workers to continue on the front line. Topics such as antimicrobial resistance, S. aureus bacteremia, clostridioides difficile, short treatments for tuberculosis, prosthetic joint infection or invasive fungal infections are included. In this article, we want to highlight, among many others, seven recently published articles that deserve our attention, full of useful information to keep us updated.

Host microbiome in tuberculosis: disease, treatment, and immunity perspectives

Tuberculosis (TB), an airborne pulmonary disease caused by Mycobacterium tuberculosis (M. tb), poses an unprecedented health and economic burden to most of the developing countries. Treatment of TB requires prolonged use of a cocktail of antibiotics, which often manifest several side effects, including stomach upset, nausea, and loss of appetite spurring on treatment non-compliance and the emergence of antibiotic resistant M. tb. The anti-TB treatment regimen causes imbalances in the composition of autochthonous microbiota associated with the human body, which also contributes to major side effects. The microbiota residing in the gastrointestinal tract play an important role in various physiological processes, including resistance against colonization by pathogens, boosting host immunity, and providing key metabolic functions. In TB patients, due to prolonged exposure to anti-tuberculosis drugs, the gut microbiota significantly loses its diversity and several keystone bacterial taxa. This loss may result in a significant reduction in the functional potency of the microbiota, which is a probable reason for poor treatment outcomes. In this review, we discuss the structural and functional changes of the gut microbiota during TB and its treatment. A major focus of the review is oriented to the gut microbial association with micronutrient profiles and immune cell dynamics during TB infection. Furthermore, we summarize the acquisition of anti-microbial resistance in M. tb along with the microbiome-based therapeutics to cure the infections. Understanding the relationship between these components and host susceptibility to TB disease is important to finding potential targets that may be used in TB prevention, progression, and cure.

Assessment of gender differences in some inflammatory cytokines of tuberculosis patients before and during treatment

Background

Gender variation is a feature of many physiological parameters including inflammatory cytokines. Inflammation is an obvious feature of Tuberculosis (TB) infection with changes in pro and anti-inflammatory cytokines.

Objective

To compare the levels of inflammatory cytokines between male and female TB patients before treatment, after 2-months and after 6-months anti-tuberculosis treatment.

Materials and methods

A total of 35 males and 25 females TB subjects were enlisted before initiation of therapy and followed up after 2-months and 6 months treatment and samples collected and analysed. Tumour necrosis factor-alpha (TNF-α), Interleukin 10 (IL-10, Interleukin -6 (IL-6), Interleukin-2 (IL-2), transforming growth factor-beta (TGF-β) were assayed by ELISA method.

Results

Before treatment, the median level of IL-6 (pg/ml) was significantly higher in males compared to female TB patients (P=0.046). While after 2-months treatment, TNF-α (pg/ml) and IL-10 (pg/ml) was significantly higher in males compared with females (P=0.008 and 0.045 respectively). Conversely, the median IL-6 (pg/ml) was significantly higher in female TB patients compared to the males (P=0.042). No significant differences were observed after 6-months treatment.

Conclusion

Gender differences exist in IL-6 before treatment and in IL-6, TNF-α and IL-10 at two months treatment. Thus, TB treatment contributes differentially to levels of inflammatory cytokines in male and female TB patients.

Impact of anti-tuberculosis treatment on hematological parameters in newly diagnosed tuberculosis patients at Jimma town: a longitudinal prospective study

Tuberculosis (TB) is a significant public health problem affecting one-third of the world's population. In 2021, 1.6 million people died from TB. TB is the 13th leading cause of death and the second leading cause of infectious death after coronavirus disease 2019. Most anti-TB drugs affect hematological parameters in patients.

METHODS

This longitudinal prospective study was conducted from 03 January to 30 December 2019. Patients who completed a course of TB treatment were candidates for analysis. Sputum and blood samples were collected from each study participant and analyzed by the Gene X-pert machine and a HumaCount 30 hematology analyzer (Human GmbH). SPSS version 20 and R programming software version 4.2.3 were used for data analysis. Friedman's test was used to assess statistical significance. P-values ​​less than 0.05 were considered statistically significant.

RESULTS

A total of 148 patients who completed the course of TB treatment correctly were a candidate for final analysis. Ninety-one (61.5%) study participants were male; the median age was 27.6±9.8 years. Moreover, most of the study participants (84.4%) had pulmonary TB. Most of the hematological parameters had changed in the phases of TB treatment. After anti-TB treatment, there is a significant difference in hematological parameters in red blood cell count, hemoglobin concentration, hematocrit percentage, platelet count, and white blood cell count.

CONCLUSION

Anemia and leucopenia are the most significant problems after TB treatment. Regular checking of these parameters is essential for the patient.

Regulation of Gut Microflora by Lactobacillus casei Zhang Attenuates Liver Injury in Mice Caused by Anti-Tuberculosis Drugs

The gut-liver axis may provide a new perspective for treating anti-tuberculosis drug-induced liver injury (ATDILI). Herein, the protective effect of Lactobacillus casei (Lc) was investigated by modulating gut microflora (GM) and the toll like receptor 4 (TLR4)-nuclear factor (NF)-κB-myeloiddifferentiationfactor 88 (MyD88) pathway. C57BL/6J mice were given three levels of Lc intragastrically for 2 h before administering isoniazid and rifampicin for 8 weeks. Blood, liver, and colon tissues, as well as cecal contents, were collected for biochemical and histological examination, as well as Western blot, quantitative real time polymerase chain reaction (qRT-PCR), and 16S rRNA analyses. Lc intervention decreased alkaline phosphatase (ALP), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and tumor necrosis factor (TNF)-α levels (p < 0.05), recovered hepatic lobules, and reduced hepatocyte necrosis to alleviate liver injury induced by anti-tuberculosis drugs. Moreover, Lc also increased the abundance of Lactobacillus and Desulfovibrio and decreased Bilophila abundance, while enhancing zona occludens (ZO)-1 and claudin-1 protein expression compared with the model group (p < 0.05). Furthermore, Lc pretreatment reduced the lipopolysaccharide (LPS) level and downregulated NF-κB and MyD88 protein expression (p < 0.05), thus restraining pathway activation. Spearman correlation analysis indicated that Lactobacillus and Desulfovibrio were positively correlated with ZO-1 or occludin protein expression and negatively correlated with pathway protein expression. Desulfovibrio had significant negative relationships with alanine aminotransferase (ALT) and LPS levels. In contrast, Bilophila had negative associations with ZO-1, occludin, and claudin-1 protein expressions and positive correlations with LPS and pathway proteins. The results prove that Lactobacillus casei can enhance the intestinal barrier and change the composition of the gut microflora. Moreover, Lactobacillus casei may also inhibit TLR4-NF-κB-MyD88 pathway activation and alleviate ATDILI.

Drug Reaction With Eosinophilia and Systemic Symptoms-Associated Perimyocarditis After Initiation of Anti-tuberculosis Therapy: A Case Report

A 34-year-old female who was recently placed on anti-tuberculosis medication with rifampin, isoniazid, pyrazinamide, and levofloxacin therapy for suspected tuberculosis reinfection presented with subjective fevers, rash, and generalized fatigue. Labs showed signs of end-organ damage with eosinophilia and leukocytosis. One day later, the patient became hypotensive with a worsening fever, and an electrocardiogram showed new diffuse ST segment elevations with an elevated troponin. An echocardiogram revealed a reduction in ejection fraction with diffuse hypokinesis, and cardiac magnetic resonance imaging (MRI) showed circumferential myocardial edema with subepicardial and pericardial inflammation. Prompt diagnosis of drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome using the European Registry of Severe Cutaneous Adverse Reaction (RegiSCAR) criteria and discontinuation of therapy was initiated. Due to the hemodynamic instability of the patient, the patient was started on systemic corticosteroids and cyclosporine, with the improvement of her symptoms and rash. A skin biopsy was performed, which revealed perivascular lymphocytic dermatitis, consistent with DRESS syndrome. As the patient's ejection fraction improved spontaneously with corticosteroids, the patient was discharged with oral corticosteroids, and a repeat echocardiogram showed full recovery of ejection fraction. Perimyocarditis is a rare complication of DRESS syndrome that is associated with degranulation and the release of cytotoxic agents into myocardial cells. Early discontinuation of offending agents and initiation of corticosteroids are essential to rapid recovery of ejection fraction and improved clinical outcomes. Multimodality imaging, including MRI, should be used to confirm perimyocardial involvement and guide the necessity for mechanical support or transplant. Further research should be on the mortality of DRESS syndrome with and without myocardial involvement, with an increased emphasis on cardiac evaluation in DRESS syndrome.

INSIGHTS INTO THERAPEUTIC LIQUID MIXTURES AND FORMULATIONS TOWARDS TUBERCULOSIS THERAPY

Therapeutic liquid mixtures, as deep eutectic systems, are considered a sustainable strategy that can be useful for the modification and enhancement of the pharmacokinetics and pharmacodynamics of different active ingredients. In this study, we assessed the stability and antibacterial activity of therapeutic liquid formulations prepared with anti-tuberculosis drugs. Tuberculosis therapy presents various pitfalls related, for example, to the administration of prolonged regimens of multiple drugs, different severe adverse effects, low compliance of the patient to treatment and the development of drug resistance. During this study, it was possible to assess the physicochemical stability of the formulations for 6 months, by polarized optical microscopy, ¹H-NMR and FTIR-ATR. Furthermore, the mixtures present an antibacterial effect against a drug-susceptible Mycobacterium tuberculosis strain (H37Rv). This was particularly evident for the mixtures with ethambutol incorporated, making them interesting to pursue with further studies and evaluation of clinical applicability. Upon infection, it was also observed that a single and higher dose appears to be more effective than lower separate doses, which could allow the production of patient-friendly formulations.

Spontaneous Resolution of Strangulated Small Bowel Obstruction in a Patient With Intestinal Tuberculosis After Starting Anti-tuberculosis Drugs: A Case Report

Intestinal tuberculosis can cause strangulated small bowel obstruction. Strangulated small bowel obstruction usually requires surgery. We report a case of a patient with intestinal tuberculosis, who developed a spontaneously resolving strangulated small bowel obstruction after the commencement of anti-tuberculosis drugs. A 72-year-old woman presented with abdominal pain and ascites was noticed on abdominal ultrasonography. Contrast-enhanced computed tomography (CT) revealed a 50-mm tumor in the ileocecal region that was darkly contrasted, along with peritoneal thickening and ascites. A malignant tumor and carcinomatous peritonitis were suspected. Colonoscopy showed an ulcerative lesion in the terminal ileum, and the acid-fast bacillus culture was positive; therefore, the patient was diagnosed with intestinal tuberculosis and was treated with isoniazid, rifampicin, ethambutol, and pyrazinamide. After commencing treatment, improvement in peritoneal thickening and ascites was confirmed using abdominal ultrasonography; therefore, we concluded that the ascites was due to tuberculous peritonitis. Six weeks after the initiation of treatment, the patient visited our facility with complaints of abdominal pain. Contrast-enhanced CT revealed unenhanced small intestinal walls, and a diagnosis of strangulated small bowel obstruction was made; however, her symptoms improved naturally. Strangulated small bowel obstruction was presumed to be due to the presence of bands as anti-tuberculosis therapy could promote fibrosis. In this case, abdominal ultrasonography was useful in the evaluation of the effects of treatment.

Magnesium Isoglycyrrhizinate Attenuates Anti-Tuberculosis Drug-Induced Liver Injury by Enhancing Intestinal Barrier Function and Inhibiting the LPS/TLRs/NF-κB Signaling Pathway in Mice

Liver injury caused by first-line anti-tuberculosis (anti-TB) drugs accounts for a high proportion of drug-induced liver injury (DILI), and gut microbiota and intestinal barrier integrity have been shown to be involved in the development of DILI. Magnesium isoglycyrrhizinate (MgIG) is the fourth-generation glycyrrhizic acid preparation, which is well documented to be effective against anti-TB DILI, but the underlying mechanism is largely unclear. In the present study, we established a BALB/c mice animal model of the HRZE regimen (39 mg/kg isoniazid (H), 77 mg/kg rifampicin (R), 195 mg/kg pyrazinamide (Z), and 156 mg/kg ethambutol (E))-induced liver injury to investigate the protective effect of MgIG against anti-TB DILI and underlying mechanisms. The results demonstrated that intraperitoneal injection of MgIG (40 mg/kg) significantly ameliorated HRZE-induced liver injury by reducing alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), and malondialdehyde (MDA) levels and improved liver pathological changes. Species composition analysis of gut microbiota showed that Lactobacillus was the only probiotic that was down-regulated by HRZE and recovered by MgIG. In addition, MgIG attenuated HRZE-induced intestinal pathology, significantly decreased HRZE-induced intestinal permeability by increasing the protein expression of tight junction protein 1 (ZO-1) and occludin, decreased HRZE-induced high lipopolysaccharide (LPS) levels, and further markedly attenuated mRNA expression levels of TNF-α, IL-6, TLR2, TLR4, and NF-κB. Supplementation with Lactobacillus rhamnosus JYLR-005 (>109 CFU/day/mouse) alleviated HRZE-induced liver injury and inflammation in mice. In summary, MgIG effectively ameliorated HRZE-induced liver injury by restoring the abundance of Lactobacillus, enhancing intestinal barrier function, and further inhibiting the activation of the LPS/TLRs/NF-κB signaling pathway. Regulating gut microbiota and promoting the integrity of intestinal barrier function may become a new direction for the prevention and treatment of anti-TB DILI.

PLGA Carriers for Controlled Release of Levofloxacin in Anti-Tuberculosis Therapy

Levofloxacin (LFX) is a highly effective anti-tuberculosis drug with a pronounced bactericidal activity against Mycobacterium tuberculosis (Mtb). In this work, an “organic solvent-free” approach has been used for the development of polylactic-co-glycolic acid (PLGA) microparticles and scaffolds containing LFX at a therapeutically significant concentration, providing for its sustained release. To achieve the target, both nonpolar supercritical carbon dioxide and polar supercritical trifluoromethane have been used. By changing the composition, surface morphology, size, and internal structure of the polymer carriers, one can control the kinetics of the LFX release into phosphate buffered saline solutions and physiological media, providing for its acceptable burst and desirable concentration in the prolonged phase. The biocompatibility and bactericidal efficacy of PLGA/LFX carriers assessed both in vitro (against Mtb phagocytosed by macrophages) and in vivo (against inbred BALB/c mice aerogenically infected with Mtb) demonstrated their anti-tuberculosis activity comparable with that of the standard daily intragastric levofloxacin administration. These results make it possible to consider the developed compositions as a promising candidate for anti-tuberculosis control release formulations providing for the further evaluation of their activity against Mtb and their metabolism in vivo over long periods of tuberculosis infection.

Interaction of Host Pattern Recognition Receptors (PRRs) with Mycobacterium Tuberculosis and Ayurvedic Management of Tuberculosis: A Systemic Approach

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb), infects the lungs' alveolar surfaces through aerosol droplets. At this stage, the disease progression may have many consequences, determined primarily by the reactions of the human immune system. However, one approach will be to more actively integrate the immune system, especially the pattern recognition receptor (PRR) systems of the host, which notices pathogen-associated molecular patterns (PAMPs) of Mtb. Several types of PRRs are involved in the detection of Mtb, including Toll-like receptors (TLRs), C-type lectin receptors (CLRs), Dendritic cell (DC) -specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), Mannose receptor (MR), and NOD-like receptors (NLRs) related to inflammasome activation. In this study, we focus on reviewing the Mtb pathophysiology and interaction of host PPRs with Mtb as well as adverse drug effects of anti-tuberculosis drugs (ATDs) and systematic TB treatment via Ayurvedic medicine.

3D host cell and pathogen-based bioassay development for testing anti-tuberculosis (TB) drug response and modeling immunodeficiency

Tuberculosis (TB) is a global health threat that affects 10 million people worldwide. Human Immunodeficiency Virus (HIV) remains one of the major contributors to the reactivation of asymptomatic latent tuberculosis (LTBI). Over the recent years, there has been a significant focus in developing in-vitro 3D models mimicking early events of Mycobacterium tuberculosis (Mtb) pathogenesis, especially formation of the granuloma. However, these models are low throughput and require extracellular matrix. In this article, we report the generation of a matrix-free 3D model, using THP-1 human monocyte/macrophage cells and mCherry-expressing Mycobacterium bovis BCG (Bacilli Camille Guérin), henceforth referred as 3D spheroids, to study the host cell-bacterial interactions. Using mCherry-intensity-based tracking, we monitored the kinetics of BCG growth in the 3D spheroids. We also demonstrate the application of the 3D spheroids for testing anti-TB compounds such as isoniazid (INH), rifampicin (RIF), as well as a host-directed drug, everolimus (EVR) as single and combinational treatments. We further established a dual infection 3D spheroid model by coinfecting THP-1 macrophages with BCG mCherry and pseudotype HIV. In this HIV-TB co-infection model, we found an increase in BCG mCherry growth within the 3D spheroids infected with HIV pseudotype. The degree of disruption of the granuloma was proportional to the virus titers used for co-infection. In summary, this 3D spheroid assay is an useful tool to screen anti-TB response of potential candidate drugs and can be adopted to model HIV-TB interactions.

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.

[2-Chloro-3-nitro-5-(tri-fluoro-meth-yl)phen-yl](piperidin-1-yl)methanone: structural characterization of a side product in benzo-thia-zinone synthesis

1,3-Benzo-thia-zin-4-ones (BTZs) are a promising new class of anti-tuberculosis drug candidates, some of which have reached clinical trials. The title compound, the benzamide derivative [2-chloro-3-nitro-5-(tri-fluoro-meth-yl)phen-yl](piper-id-in-1-yl)methanone, C13H12ClF3N2O3, occurs as a side product as a result of competitive reaction pathways in the nucleophilic attack during the synthesis of the BTZ 8-nitro-2-(piperidin-1-yl)-6-(tri-fluoro-meth-yl)-1,3-benzo-thia-zin-4-one, following the original synthetic route, whereby the corresponding benzoyl iso-thio-cyanate is reacted with piperidine as secondary amine. In the title compound, the nitro group and the nearly planar amide group are significantly twisted out of the plane of the benzene ring. The piperidine ring adopts a chair conformation. The tri-fluoro-methyl group exhibits slight rotational disorder with a refined ratio of occupancies of 0.972 (2):0.028 (2). There is structural evidence for inter-molecular weak C-H⋯O hydrogen bonds.

LC-QToF-MS method for quantification of ethambutol, isoniazid, pyrazinamide and rifampicin in human plasma and its application

In this research, we developed and validated a liquid chromatography coupled to mass spectrometry (LC-QToF-MS) method for simultaneous quantification of the anti-tuberculosis drugs ethambutol, isoniazid, pyrazinamide and rifampicin in human plasma. Plasma samples spiked with cimetidine (internal standard) were extracted using protein precipitation with acetonitrile containing 1% formic acid. Separation was performed using a C₁₈ column under flow gradient conditions with water and acetonitrile, both containing 5 mm ammonium formate and 0.1% formic acid. The method was validated according to the ANVISA and US Food and Drug Administration guidelines for bioanalytical method validation. The calibration curve was linear over a concentration range of 0.2-5 μg ml^-1 for ethambutol, 0.2-7.5 μg ml^-1 for isoniazid, 1-40 μg ml^-1 for pyrazinamide and 0.25-2 μg ml^-1 for rifampicin, all with adequate precision and accuracy. The method was reproducible, selective and free of carryover and matrix effects. The validated LC-QToF-MS method was successfully applied to real samples and shown to be applicable to future therapeutic and pharmacokinetic monitoring studies.

Determinants of serum concentration of first-line anti-tuberculosis drugs from China

Therapeutic drug monitoring has been employed in anti-tuberculosis (TB) drugs to assess optimal dose for maximum therapeutic effects and minimal toxicity. But the determinants of serum concentration need further evidences.In a retrospective case-control study, clinical and laboratory data were collected from 717 in-patients with TB at Xi'an Chest Hospital, China. Two hours serum concentrations of isoniazid, rifampicin, pyrazinamide as well as ethambutol were obtained and analyzed by liquid chromatography-tandem mass spectrometry.The month 2 culture conversion group had lower concentration of isoniazid, pyrazinamide, and ethambutol than month 1 group. Statistical analysis showed that serum concentrations of isoniazid, rifampicin, pyrazinamide, and ethambutol revealed a positive relationship with dose (mg/kg) (P < .001, P < .001, P < .001, and P = .003, respectively). Furthermore, isoniazid concentration was related to smoking (P = .009) and prior TB (P = .011), while rifampicin and pyrazinamide concentrations were correlated to sex (P = .004 and 0.025, respectively). Ethambutol concentration was associated with creatinine clearance (Ccr, P = .002).It is necessary to optimize drug doses using therapeutic drug monitoring while considering the following determinants: weight, smoking status, prior TB, sex, and Ccr. Furthermore, low 2 hours serum concentrations can be associated with longer culture conversion.

Clinical features and risk factors for gout attacks during anti-tuberculosis treatment: A case-control study in South Korea

AIM

This study aimed to investigate the clinical features and risk factors of gout attacks during anti-tuberculosis (TB) treatment in South Korea.

METHOD

We investigated the clinical characteristics of 49 patients who suffered from gout attacks while taking anti-TB medications. Among them, 25 TB patients having newly developed gout attacks without prior history of gout were set to the gout group. Seventy-five age- and sex-matched TB patients without gout attacks during anti-TB therapy were randomly selected as the control group. The demographics, clinical features, and laboratory findings between the two groups were compared to establish risk factors of gout attack during anti-TB treatment.

RESULTS

The gout patients had a mean age of 67.7 ± 13.2 years and 39 patients (79.6%) were male. Approximately half of the patients experienced an attack within 2 months of treatment initiation. The attacks typically involved lower extremity joints (87.8%). The serum uric acid (SUA) levels were significantly elevated at 2 and 6 months after starting anti-TB medication compared with those at baseline. In the case-control study, the factors associated with gout attack were higher body mass index (BMI), higher pre-treatment SUA levels, dyslipidemia, and reduced renal function. In the multivariate model, higher BMI, chronic kidney disease (CKD), and pre-treatment hyperuricemia (SUA ≥ 6.8 mg/dL) were independent risk factors of gout attack while taking anti-TB medication.

CONCLUSIONS

Patients with high BMI, CKD, and pre-treatment hyperuricemia are at a higher risk of gout attack during TB treatment.

Prominence of Oxidative Stress in the Management of Anti-tuberculosis Drugs Related Hepatotoxicity

Advanced medical services and treatments are available for treating Tuberculosis. Related prevalence has increased in recent times. Unfortunately, the continuous consumption of related drugs is also known for inducing hepatotoxicity which is a critical condition and cannot be overlooked. The present review article has focused on the pathways causing these toxicities and also the role of enzyme CYP2E1, hepatic glutathione, Nrf2-ARE signaling pathway, and Membrane Permeability Transition as possible targets which may help in preventing the hepatotoxicity induced by the drugs used in the treatment of tuberculosis.

Evaluation of Adverse Reactions Induced by Anti-Tuberculosis Drugs in Hospital Pulau Pinang

Background

The use of multi-drug regimens in tuberculosis (TB) treatment has been associated with undesirable adverse drug reactions (ADRs). This study aims to assess the incidence and impact of ADRs on TB treatment in Hospital Pulau Pinang.

Methods

This cross-sectional study was conducted via retrospective review of outpatients’ medical records. Details regarding ADRs were identified by a pharmacist and verified by a consultant respiratory physician.

Results

A total of 91 cases, out of 210 patients enrolled in this study, were detected with 75 patients (35.7%) experienced at least one ADR. The three most common ADRs detected were cutaneous adverse drug reactions (CADRs) (21.0%), drug-induced hepatitis (DIH) (7.1%) and gastrointestinal disturbance (4.8%). Pyrazinamide was the most common causative agent and 15.7% of all TB patients required treatment modification due to ADRs. Females were shown to have a higher tendency to develop ADRs than the males in this study (P = 0.009). The development of ADRs was shown not to affect the TB treatment outcomes (P = 0.955).

Conclusion

The incidence of ADRs in this study was high so it is important to identify the risk factors for ADRs and the individuals who have those risk factors when initiating anti-TB drugs. These individuals require special attention when anti-TB drugs are initiated.

Delayed Sputum Culture Conversion in Tuberculosis-Human Immunodeficiency Virus-Coinfected Patients With Low Isoniazid and Rifampicin Concentrations

Background

The relationship between concentrations of antituberculosis drugs, sputum culture conversion, and treatment outcome remains unclear. We sought to determine the association between antituberculosis drug concentrations and sputum conversion among patients coinfected with tuberculosis and human immunodeficiency virus (HIV) and receiving first-line antituberculosis drugs.

Methods

We enrolled HIV-infected Ugandans with pulmonary tuberculosis. Estimation of first-line antituberculosis drug concentrations was performed 1, 2, and 4 hours after drug intake at 2, 8, and 24 weeks of tuberculosis treatment. Serial sputum cultures were performed at each visit. Time-to-event analysis was used to determine factors associated with sputum culture conversion.

Results

We enrolled 268 HIV-infected patients. Patients with low isoniazid and rifampicin concentrations were less likely to have sputum culture conversion before the end of tuberculosis treatment (hazard ratio, 0.54; 95% confidence interval, .37-.77; P = .001) or by the end of follow-up (0.61; .44-.85; P = .003). Patients in the highest quartile for area under the rifampicin and isoniazid concentration-time curves for were twice as likely to experience sputum conversion than those in the lowest quartile. Rifampicin and isoniazid concentrations below the thresholds and weight <55 kg were both risk factors for unfavorable tuberculosis treatment outcomes. Only 4.4% of the participants had treatment failure.

Conclusion

Although low antituberculosis drug concentrations did not translate to a high proportion of patients with treatment failure, the association between low concentrations of rifampicin and isoniazid and delayed culture conversion may have implications for tuberculosis transmission. Clinical Trials Registration: NCT01782950.

Substantially Higher and Earlier Occurrence of Anti-Tuberculosis Drug-Related Adverse Reactions in HIV Coinfected Tuberculosis Patients: A Matched-Cohort Study

Little information exists on the frequency, severity, and timing of first-line anti-tuberculosis drug-related adverse events (TB-AEs) in HIV-tuberculosis coinfected (HIV-TB) patients in the antiretroviral therapy (ART) era. This matched-cohort study included HIV-TB patients as cases and HIV-uninfected tuberculosis (non-HIV-TB) patients as controls. Tuberculosis was culture-confirmed in both groups. Cases were matched to controls in a 1:4 ratio on age, sex, and year of diagnosis. TB-AEs were defined as Grade 2 or higher requiring drug discontinuation/regimen change. From 2003 to 2015, 94 cases and 376 controls were analyzed (95% men, 98% Asians). Standard four-drug combination therapy was initiated in 91% of cases and 89% of controls (p = 0.45). Cases had a higher frequency of TB-AE [51% (48/94) vs. 10% (39/376), p < 0.001]. Their major TB-AEs were fever (19%), rash (11%), and neutropenia (11%). TB-AEs were more severe in cases [Grade 3 or higher: cases (71%, 34/48) vs. controls (49%, 19/39), p < 0.001]. The time from treatment initiation to TB-AE was shorter in cases [median 18 (interquartile range 12-28) vs. 27 (15-57) days, p = 0.027], and 73% of TB-AEs in cases occurred within 4 weeks of starting anti-tuberculosis treatment. HIV infection was an independent risk factor for TB-AEs in the multivariate Cox analysis [adjusted HR (aHR): 6.96; 95% confidence interval: 3.93-12.3]. TB-AEs occurred more frequently in HIV-TB than in non-HIV-TB patients, and were more severe. The majority of TB-AEs occurred within 4 weeks of initiating anti-tuberculosis treatment. Because TB-AEs may delay ART initiation, careful monitoring during this period is warranted in coinfected patients.

Host-Directed Therapeutic Strategies for Tuberculosis

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of morbidity and mortality in humans worldwide. Currently, the standard treatment for TB involves multiple antibiotics administered for at least 6 months. Although multiple antibiotics therapy is necessary to prevent the development of drug resistance, the prolonged duration of treatment, combined with toxicity of drugs, contributes to patient non-compliance that can leads to the development of drug-resistant Mtb (MDR and XDR) strains. The existence of comorbid conditions, including HIV infection, not only complicates TB treatment but also elevates the mortality rate of patients. These facts underscore the need for the development of new and/or improved TB treatment strategies. Host-directed therapy (HDT) is a new and emerging concept in the treatment of TB, where host response is modulated by treatment with small molecules, with or without adjunct antibiotics, to achieve better control of TB. Unlike antibiotics, HDT drugs act by directly modulating host cell functions; therefore, development of drug resistance by infecting Mtb is avoided. Thus, HDT is a promising treatment strategy for the management of MDR- and XDR-TB cases as well as for patients with existing chronic, comorbid conditions such as HIV infection or diabetes. Functionally, HDT drugs fine-tune the antimicrobial activities of host immune cells and limit inflammation and tissue damage associated with TB. However, current knowledge and clinical evidence is insufficient to implement HDT molecules as a stand-alone, without adjunct antibiotics, therapeutic modality to treat any form of TB in humans. In this review, we discuss the recent findings on small molecule HDT agents that target autophagy, vitamin D pathway, and anti-inflammatory response as adjunctive agents along with standard antibiotics for TB therapy. Data from recent publications show that this approach has the potential to improve clinical outcome and can help to reduce treatment duration. Thus, HDT can contribute to global TB control programs by potentially increasing the efficiency of anti-TB treatment.

Genome-Wide Association and Replication Study of Hepatotoxicity Induced by Antiretrovirals Alone or with Concomitant Anti-Tuberculosis Drugs

Drug-induced hepatotoxicity (DIH) is a common adverse event that is associated with both antiretroviral (ARV) and anti-tuberculosis drugs (ATD). Moreover, the genetic variations predisposing ARV- and ARV-ATD-induced liver toxicity in African populations are not well investigated, despite the two diseases being the major global health problems in sub-Saharan Africa. We performed a genome-wide association study (GWAS) and replication study to identify the genetic variants linked to the risk of developing DIH due to ARV drugs alone, and ARV-ATD co-treatment in Ethiopian HIV-positive patients. Treatment-naïve newly diagnosed HIV patients (n = 719) with or without tuberculosis (TB) co-infection were enrolled prospectively and received efavirenz-based ARV therapy with or without rifampicin-based short course ATD, respectively. Whole-genome genotyping was performed by using the Illumina Omni Express Exome Bead Chip genotyping array with 951,117 single nucleotide polymorphisms (SNPs) on a total of 41 cases of DIH, and 452 people without DIH (treatment tolerants). The replication study was carried out for 100 SNPs with the lowest p-values (top SNPs) by using an independent cohort consisting of 18 DIH cases and 208 treatment tolerants. We identified a missense SNP rs199650082 (2756G→A, R919Q, p = 1.4 × 10^-6, odds ratio [OR] = 18.2, 95% confidence interval [CI] = 7.1-46.9) in an endoplasmic reticulum to the nucleus signaling-1 (ERN1) gene on chromosome 17 to be associated with DIH in the ARV-only cohort. In the ARV-ATD co-treatment groups, rs4842407, a long intergenic noncoding RNAs (lincRNAs) transcript variant on chromosome 12, was associated with DIH (p = 5.3 × 10^-7, OR = 5.4, 95% CI = 2.8-10.3). These genetic variants that are putatively associated with DIH due to ARV drugs alone and ARV-ATD co-treatment establish a foundation for future personalized medicine in people with HIV and TB and call for larger studies in independent populations.

Cohort profile of a study on outcomes related to tuberculosis and antiretroviral drug concentrations in Uganda: design, methods and patient characteristics of the SOUTH study

PURPOSE

Tuberculosis (TB) is a leading cause of death among people living with HIV in sub-Saharan Africa. Several factors influence the efficacy of TB treatment by leading to suboptimal drug concentrations and subsequently affecting treatment outcome. The aim of this cohort is to determine the association between anti-TB drug concentrations and TB treatment outcomes.

PARTICIPANTS

Patients diagnosed with new pulmonary TB at the integrated TB-HIV outpatient clinic in Kampala, Uganda, were enrolled into the study and started on first-line anti-TB treatment.

FINDINGS TO DATE

Between April 2013 and April 2015, the cohort enrolled 268 patients coinfected with TB/HIV ; 57.8% are male with a median age of 34 years (IQR 29-40). The median time between the diagnosis of HIV and the diagnosis of TB is 2 months (IQR 0-22.5). The majority of the patients are antiretroviral therapy naive (75.4%). Our population is severely immunosuppressed with a median CD4 cell count at enrolment of 163 cells/µL (IQR 46-298). Ninety-nine per cent of the patients had a diagnosis of pulmonary TB confirmed by sputum microscopy, Xpert/RIF or culture and 203 (75.7%) have completed TB treatment with 5099 aliquots of blood collected for pharmacokinetic analysis.

FUTURE PLANS

This cohort provides a large database of well-characterised patients coinfected with TB/HIV which will facilitate the description of the association between serum drug concentrations and TB treatment outcomes as well as provide a research platform for future substudies including evaluation of virological outcomes.

TRIAL REGISTRATION NUMBER

NCT01782950; Pre-results.

Determination of anti-tuberculosis drug concentration and distribution from sustained release microspheres in the vertebrae of a spinal tuberculosis rabbit model

There have been several sustained-release materials containing anti-tuberculosis drug to enhance concentration in foci of spinal tuberculosis but what map by which composite drug delivery system is released is not known. Isoniazid (INH) lactic-co-glycolic acid (PLGA) and INH hydroxyapatite (HA) microspheres were prepared, respectively. The rabbits were modeled by tuberculosis strains and sustained-release microspheres were incubated in the foci. INH concentrations in the HA group were higher than those of INH and PLGA groups at L3, L4, and L5 vertebra 2 days after the drugs were embedded (p < 0.05). INH concentrations in the HA group were higher than those of INH and PLGA groups in L3 vertebra 4 days after the drugs were embedded (p < 0.05). INH concentrations in the PLGA group were higher than those of INH and HA groups in L5 vertebra; INH concentrations of the HA group were higher than those of INH and PLGA groups in L4 vertebra 6 days after the drugs were embedded (p < 0.05). These microspheres can enhance INH concentration in the foci. Furthermore, HA microspheres elicit osteogenic effects. HA is better than PLGA in terms of infiltration, but PLGA is better than HA in terms of distribution. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:200-208, 2017.

Bedaquiline as part of combination therapy in adults with pulmonary multi-drug resistant tuberculosis

INTRODUCTION

Few innovative anti-microbial products have been brought to market in recent years to combat the global multidrug resistant-tuberculosis (MDR-TB) epidemic. Bedaquiline, a novel oral diarylquinoline, was approved by the US FDA as a part of combination therapy in adults with pulmonary MDR-TB based on phase II trials.

AREA COVERED

Pubmed searches were conducted using search terms bedaquiline, diarylquinoline, R207910, and TMC207 was performed. Supplementary sources included World Health Organization, Clinicaltrial.gov, US Food and Drug Administration. Bedaquiline is an ATP synthase inhibitor specific for M. tuberculosis and some nontuberculous mycobacteria. It is metabolized by CYP3A4 and it's drug exposure can be influenced by inducers and inhibitors of this enzyme. Phase II studies showed promising results on efficacy of bedaquiline when being used in combination with a background regimen for MDR-TB. Main safety concerns include QTc prolongation and hepatotoxicity. Phase III trials are ongoing to confirm efficacy findings from phase II studies and provide additional evidence of safety and efficacy. Expert commentary: Critical data for long-term efficacy and safety are incomplete and scarce, supporting the cautious use of bedaquiline.

Clinical features and treatment of drug fever caused by anti-tuberculosis drugs

BACKGROUND AND AIMS

Tuberculosis is a major global health problem. However, anti-tuberculosis drug treatment has many adverse effects, such as drug-caused fever. The aim of this study was to investigate the clinical features and treatments of anti-tuberculosis drugs-induced fever.

METHODS

A total of 78 inpatients and outpatients with pulmonary tuberculosis accompanied by drug fever during the anti-tuberculosis treatment were analysed retrospectively from April 2006 to March 2013.

RESULTS

Among the anti-tuberculosis drugs that caused the drug fever, rifampicin was the most common one, followed by para-aminosalicylic and pyrazinamide. The symptoms occurred within 2 months after treatment, mainly in the 1-3 weeks, and the main symptom was high fever with body temperature above 39°C. The accompanying symptoms include rash, chills, headache, stuffy nose, runny nose, nausea, vomiting and joint pain. Routine blood examination found that eosinophilia increased in 15 cases and decreased in another 15. Among 63 patients who underwent liver function tests, there were 10 cases of abnormal function and 4 cases of liver damage. When the drug fever was suspected, the measure of withdrawal was taken first. All the suspected drugs were withdrawn in 59 cases, while gradual withdrawal was conducted in 19 cases. Patients with complications were first treated in accordance with the principles of complications treatment and then were gradually given some drugs after recovery. The patients without complications were gradually given some drugs after the body temperature was back to normal.

CONCLUSION

Drug fever is an allergic reaction, the resolution of which depends on whether it was accompanied by liver damage and/or rash or not.

Evaluation of a biphasic media assay for pyrazinamide drug susceptibility testing of Mycobacterium tuberculosis

OBJECTIVES

Pyrazinamide is a key first-line tuberculosis drug. Reliable drug susceptibility testing (DST) data are of clinical importance, but in vitro testing is challenging since the activity of pyrazinamide is pH sensitive. The BACTEC MGIT 960 is considered the principal reference technique, but Wayne's test is an alternative, although it may be difficult to interpret. A further alternative is the use of a biphasic media assay (BMA). The objective of this work was to evaluate the BMA against the MGIT method and with screening of pncA gene mutations.

METHODS

Twenty strains were inoculated in tubes containing 2 mL of Löwenstein-Jensen (LJ) medium and 2 mL of semi-solid Kirchner medium with a critical concentration of 66 mg/L pyrazinamide at a pH of 5.2 or 5.5, incubated for 2 weeks and visually read. The results obtained were compared with MGIT 960 and DNA sequencing.

RESULTS

Results were obtained in duplicate for 19 strains. One strain failed to grow on two occasions and only one result was available. Reproducibility was 95%. Eleven of the 19 strains were susceptible to pyrazinamide, whereas 7 were resistant. One strain was susceptible initially and pyrazinamide resistant on repeat testing. At pH 5.5, two strains reported as susceptible at pH 5.2 gave resistant results.

CONCLUSIONS

The BMA might serve as a reliable low-cost DST alternative for pyrazinamide, particularly in laboratories using locally made solid media for DST. Its major drawback is the time to result. A reliable and affordable test method for the detection of pyrazinamide resistance is needed, especially in settings where multidrug-resistant tuberculosis is increasing. Proficiency testing should be routinely introduced wherever pyrazinamide DST is performed.

Clinical significance of 2 h plasma concentrations of first-line anti-tuberculosis drugs: a prospective observational study

OBJECTIVES

To study 2 h plasma concentrations of the first-line tuberculosis drugs isoniazid, rifampicin, ethambutol and pyrazinamide in a cohort of patients with tuberculosis in Denmark and to determine the relationship between the concentrations and the clinical outcome.

METHODS

After 6-207 days of treatment (median 34 days) 2 h blood samples were collected from 32 patients with active tuberculosis and from three patients receiving prophylactic treatment. Plasma concentrations were determined using LC-MS/MS. Normal ranges were obtained from the literature. Clinical charts were reviewed for baseline characteristics and clinical status at 2, 4 and 6 months after the initiation of treatment. At a 1 year follow-up, therapy failure was defined as death or a relapse of tuberculosis.

RESULTS

Plasma concentrations below the normal ranges were frequently observed: isoniazid in 71%, rifampicin in 58%, ethambutol in 46%, pyrazinamide in 10% and both isoniazid and rifampicin in 45% of the patients. The plasma concentrations of isoniazid correlated inversely with the C-reactive protein level at the time of sampling (P = 0.001). During 1 year of follow-up, therapy failure occurred in five patients. Therapy failure occurred more frequently when the concentrations of isoniazid and rifampicin were both below the normal ranges (P = 0.013) and even more frequently when they were below the median 2 h drug concentrations obtained in the study (P = 0.005).

CONCLUSIONS

At 2 h, plasma concentrations of isoniazid and rifampicin below the normal ranges were frequently observed. The inverse correlation between the plasma concentrations of isoniazid and C-reactive protein indicate a suboptimal treatment effect at standard dosing regimens. Dichotomization based on median 2 h drug concentrations was more predictive of outcome than dichotomization based on normal ranges.

Multidrug-resistant and extensively drug-resistant tuberculosis: a review of current concepts and future challenges

Multidrug-resistant and extensively drug-resistant tuberculosis are recent global health issues, which makes tuberculosis - after the success of short course treatment during the second half of the last century - a major health challenge. Globalisation, health inequalities, competing economic interests and political instability contribute substantially to the spread of drug-resistant strains, which are associated with high rates of morbidity and mortality. Issues such as increasing transmission of drug-resistant strains, poor diagnostic coverage and a lengthy, toxic treatment need to be overcome by innovative approaches to tuberculosis control, prevention, diagnostics and treatment. This review addresses recent developments and future concepts.

The pyrazinamide susceptibility breakpoint above which combination therapy fails

Objectives

To identify the pyrazinamide MIC above which standard combination therapy fails.

Methods

MICs of pyrazinamide were determined for Mycobacterium tuberculosis isolates, cultured from 58 patients in a previous randomized clinical trial in Cape Town, South Africa. The MICs were determined using BACTEC MGIT 960 for isolates that were collected before standard treatment with isoniazid, rifampicin, pyrazinamide and ethambutol commenced. Weekly sputum collections were subsequently made for 8 weeks in order to culture M. tuberculosis in Middlebrook broth medium. Classification and regression tree (CART) analysis was utilized to identify the pyrazinamide MIC predictive of sputum culture results at the end of pyrazinamide therapy. The machine learning-derived susceptibility breakpoints were then confirmed using standard association statistics that took into account confounders of 2 month sputum conversion.

Results

The pyrazinamide MIC range was 12.5 to >100 mg/L for the isolates prior to therapy. The epidemiological 95% cut-off value was >100 mg/L. The 2 month sputum conversion rate in liquid cultures was 26% by stringent criteria and 48% by less stringent criteria. CART analysis identified an MIC breakpoint of 50 mg/L, above which patients had poor sputum conversion rates. The relative risk of poor sputum conversion was 1.5 (95% CI: 1.2–1.8) for an MIC >50 mg/L compared with an MIC ≤50 mg/L.

Conclusions

We propose a pyrazinamide susceptibility breakpoint of 50 mg/L for clinical decision making and for development of rapid susceptibility assays. This breakpoint is identical to that identified using computer-aided simulations of hollow fibre system output.

Efficacy and safety of anti-tuberculosis drugs in HIV-positive patients: a prospective study

OBJECTIVES

To assess the efficacy and safety of anti-tuberculosis drugs in HIV-positive patients at a tertiary care teaching hospital.

MATERIALS AND METHODS

As a part of an ongoing study of opportunistic infections (OIs) in HIV-positive patients, drug treatment in patients suffering from tuberculosis was assessed to determine its efficacy and safety. Based on prevalence data for last three years, a purposive sampling of study population was carried out in this observational, prospective, single centre study. Tuberculosis (TB) was the most common OI observed. The selected patients were followed up for a period of one year to evaluate the clinical course and outcome of OIs, and the efficacy and safety of drugs used was checked.

RESULTS

Tuberculosis was observed in 89 out of 134 enrolled patients. These included 79 adults and 10 children. Males (66.2%) were commonly affected. Extra pulmonary TB (73%) was the most common manifestation with abdominal TB observed in 55 (61.7%) patients. All patients were treated in accordance with the Revised National Tuberculosis Control Programme (RNTCP) guidelines as recommended by National AIDS Control Organization (NACO), India. Outcome of TB was assessable in 70 patients. Majority (82.8%) of the patients were cured, while 12 patients (17.1%) died during the course of treatment. A total of 149 ADRs were observed in 67 (75.2%) patients. Majority of ADRs (n = 147) were non-serious and did not warrant a change in therapy. Discoloration of urine was the most common ADR observed.

CONCLUSION

TB is the most common opportunistic infection in HIV-positive patients with abdominal TB being the most common manifestation. RNTCP and NACO guidelines are adhered to in these patients. Anti-tuberculosis drugs are well tolerated and effective in majority of the patients.

Unexpected N-acetylation of capreomycin by mycobacterial Eis enzymes

OBJECTIVES

The enhanced intracellular survival (Eis) protein from Mycobacterium tuberculosis (Eis_Mtb), a regio-versatile N-acetyltransferase active towards many aminoglycosides (AGs), confers resistance to kanamycin A in some cases of extensively drug-resistant tuberculosis (XDR-TB). We assessed the activity of Eis_Mtb and of its homologue from Mycobacterium smegmatis (Eis_Msm) against a panel of anti-tuberculosis (TB) drugs and lysine-containing compounds.

METHODS AND RESULTS

Both enzymes acetylated capreomycin and some lysine-containing compounds, but not other non-AG non-lysine-containing drugs tested. Modelling studies predicted the site of modification on capreomycin to be one of the two primary amines in its β-lysine side chain. Using Eis_Mtb, we established via nuclear magnetic resonance (NMR) spectroscopy that acetylation of capreomycin occurs on the ε-amine of the β-lysine side chain. Using Msm, we also demonstrated for the first time to our knowledge that acetylation of capreomycin results in deactivation of the drug.

CONCLUSIONS

Eis is a unique acetyltransferase capable of inactivating the anti-TB drug capreomycin, AGs and other lysine-containing compounds.

A guide to the management of tuberculosis in patients with chronic liver disease

Tuberculosis remains one of the 'Captains of the Men of Death' even today, particularly in the developing world. Its frequency is increased 14-fold in patients with chronic liver diseases (CLD) and liver cirrhosis, more so in those with decompensated disease, probably due to the cirrhosis-associated immune dysfunction syndrome, and case-fatality rates are high. The diagnosis of tuberculosis, particularly the interpretation of the Mantoux test, is also fraught with difficulties in CLD, especially after previous BCG vaccination. However, the greatest challenge in the patient with CLD or liver cirrhosis and tuberculosis is managing their therapy since the best first-line anti-tuberculosis drugs are hepatotoxic and baseline liver function is often deranged. Frequency of hepatotoxicity is increased in those with liver cirrhosis, chronic hepatitis B and chronic hepatitis C, possibly related to increased viral loads and may be decreased following antiviral therapy. If hepatotoxicity develops in those with liver cirrhosis, particularly decompensated cirrhosis, the risk of severe liver failure is markedly increased. Currently, there are no established guidelines for anti-tuberculosis therapy (ATT) in CLD and liver cirrhosis although the need for such guidelines is self-evident. It is proposed that ATT should include no more than 2 hepatotoxic drugs (RIF and INH) in patients with CLD or liver cirrhosis and stable liver function [Child-Turcotte-Pugh (CTP) ≤7], only a single hepatotoxic drug (RIF or INH) in those with advanced liver dysfunction (CTP 8-10) and no hepatotoxic drugs with very advanced liver dysfunction (CTP ≥11). A standard protocol should be followed for monitoring ATT-related hepatotoxicity and for stop rules and reintroduction rules in all these patients, on the lines proposed here. It is hoped that these proposals will introduce uniformity and result in streamlining the management of these difficult patients.

ABCC2 Haplotype is Associated With Antituberculosis Drug-Induced Maculopapular Eruption

Genetic variants in ATP-binding cassette (ABC) transporter genes are associated with increased susceptibility to adverse drug reactions. We hypothesized that genetic variant ABC transporters (ABCB1 and ABCC2) may be candidate markers for predicting maculopapular eruption (MPE) induced by antituberculosis therapy. We compared the genotype distributions of single nucleotide polymorphisms and haplotypes in the ABCB1 and ABCC2 genes between 62 antituberculosis drug (ATD)-induced MPE cases and 159 ATD-tolerant controls using multivariate logistic regression analysis. There was no significant association between genetic polymorphisms in ABCB1 and ATD-induced MPE (P>0.05). Among seven selected SNPs of ABCC2, IVS3-49C>T in intron and I1324I were associated with ATD-induced MPE (P=0.029 and 0.036, respectively). In an analysis of the ABCC2 haplotypes (ht; -1549G>A_-24C>T_IVS3-49C>T_V417I), ht1[G-C-C-G] was significantly associated with ATD-induced MPE (P=0.032, OR=0.35, 95% CI: 0.16-0.95). No significant association between the other haplotypes and ATD-induced MPE was observed. An ABCC2 haplotype is associated with the presence of ATD-induced MPE in patients with tuberculosis and may be a genetic risk factor for the development of MPE induced by ATD.