Isoniazid resistance in patients with Extrapulmonary Tuberculosis using line probe assay in a private multispecialty hospital in Bangalore,India

We aimed to study the rate of isoniazid (INH) resistance in Extrapulmonary Tuberculosis samples from a private care setting.A Line probe assay was performed on 74 culture isolates of Mycobacterium tuberculosis or directly on extrapulmonary samples received in our laboratory from 2018 to 2021.The INH mono-resistance among these extrapulmonary samples was 6.7%. (5 among 74) (95% CI: 1.04%–12.48%) Resistance to rifampicin was not detected.Increasing the availability and leveraging public private partnerships in hospitals for universal testing for INH resistance may increase detection of INH monoresistance in EP-TB and improve the strategy for TB elimination.     

食管结核误诊为食管癌临床分析

目的分析食管结核的临床特点、误诊原因及防范措施。方法回顾性分析误诊为食管癌的食管结核2例的临床资料。结果1例因吞咽困难2个月,进行性加重伴持续性胸骨后疼痛1月余就诊,院外多次行胃镜及病理检查均提示食管癌可能性大,入院后经胃镜、病理检查及实验室检查结果确诊食管结核,给予三联抗结核治疗,症状明显好转。1例因进行性吞咽困难伴乏力、消瘦5个月就诊,两次胃镜及活检均考虑食管癌,择期行手术治疗,术后病理检查提示食管结核,给予三联抗结核治疗,病情明显好转。结论食管结核临床少见,部分患者无结核中毒症状,且临床表现无特异性,极易误诊为食管癌,提示临床应加强对本病的认识,多次多部位行病理检查,必要时行诊断性抗结核治疗,可一定程度避免误诊的发生。     

异烟肼血药浓度的影响因素分析

目的：分析影响异烟肼血药浓度的因素。方法：对2013年9月~2017年12月的97例异烟肼血药浓度监测患者作回顾性分析,探讨影响异烟肼血药浓度的主要因素。结果：该药血药浓度与体表面积和白蛋白水平存在显著相关性。结论：密切关注具有危险因素患者的血药浓度。     

Novel compounds targeting InhA for TB therapy

Tuberculosis (TB) is described as lethal disease in the world. Resistant to TB drugs is the main reason to have unfavourable outcomes in the treatment of TB. Therefore, new agents to replace existing drugs are urgently needed. Previous reports suggested that InhA inhibitors, an enoyl-ACP-reductase, might provide auspicious candidates which can be developed into novel antitubercular agents. In this review, we explain the role of InhA in the resistance of isoniazid. Furthermore, five classes of InhA inhibitors, which display novel binding modes and deliver evidence of their prosperous target engagement, have been debated.     

Efficacy of isoniazid salvage therapy for latent tuberculosis infection in patients with immune-mediated inflammatory disorders – A retrospective cohort study in Taiwan

Background

Active tuberculosis (TB) in patients with latent tuberculosis infection (LTBI) was associated with use of biological agents for immune-mediated inflammatory disorders (IMIDs). For decreasing active TB, isoniazid prophylaxis therapy was administered before biologic therapy among IMID patients with LTBI. However, for patients who had been received biologics for a long time with unknown status of LTBI or exposure history of active TB, the prevalence of LTBI and efficacy of isoniazid therapy were unclear.

复合三联抗结核药聚乳酸-羟基乙酸缓释微球的制备及体外释药特性

目的 :制备复合异烟肼(H)、利福平(R)、吡嗪酰胺(Z)的聚乳酸-羟基乙酸(HRZ/PLGA)缓释微球,观察其理化性质和体外缓释特性。方法:以PLGA(450mg)为载体,避光条件下称取H(40mg)、R(60mg)、Z(125mg),采用复乳-溶剂挥发法制备HRZ/PLGA缓释微球,应用扫描电镜观察微球的形态特征;应用高效液相色谱法(HPLC)测定其载药量、包封率;采用溶出法、HPLC于3h、6h、12h、1d、2d、3d、6d、9d、12d、15d、20d、25d、30d、40d、50d测定H、R、Z三种药物的浓度,观察其是否均大于10倍最低抑菌浓度(MIC),计算其日均释药率、累计释药率。结果:HRZ/PLGA微球在电镜下观察呈圆球形,平均粒径为10.3±4.7μm;H、R、Z三种药物的载药量分别为(18.02±0.36)%、(22.46±0.24)%、(21.68±0.37)%,包封率分别为(54.79±1.13)%、(72.35±0.39)%、(67.21±0.68)%;体外缓释试验显示微球缓释前12d左右,三种药物的累计缓释度均超过了50%,日均释药率分别为5.05%、4.89%、6.86%;第12天后三药的缓释基本趋于稳定,日均释药率分别为0.17%、0.26%、0.16%;三种药物缓释到50d时均大于10倍MIC。结论:HRZ/PLGA微球具有优良的载药及药物缓释效果,是一种理想的复合抗结核药物缓释系统。     

抗结核药缓释涂层在兔脊柱结核模型体内的抗结核性能及组织相容性观察

目的:观察抗结核药异烟肼(H)、利福平(R)、吡嗪酰胺(Z)缓释涂层在兔脊柱结核模型体内的抗结核性能及组织相容性。方法:选取健康新西兰兔构建L4/5脊柱结核模型,将建模成功的60只模型兔随机分为A、B、C三组,每组20只,其中A组(实验组)病灶清除术后植入包裹HRZ缓释涂层的自体髂骨;B组(对照组)病灶清除术后植入包裹空白涂层的自体髂骨;C组(空白对照组)病灶清除术后单纯植入自体髂骨。术后观察实验兔一般状况及伤口情况;造模前1d、病灶清除术前及术后1d、3d、7d、14d、28d、56d、84d、112d进行血沉(ESR)、C反应蛋白(CRP)检测;术前以及术后14d、28d、56d进行肝肾功能检测;术后28d时A组随机处死5只兔,取心脏、肝脏、脊髓、脾脏及肾脏组织制作病理切片观察;术后56d行脊柱X线片检查后,每组随机处死5只兔在植骨部位局部取材进行骨-材料界面组织病理学观察。结果:术后B组1只兔切口感染,C组1只兔死亡、1只兔截瘫,其余兔术后一般状况良好。三组造模前和手术前的ESR和CRP均无统计学差异(P0.05);三组手术前的ESR和CRP均较造模前显著性升高(P0.01)。三组术后1d时ESR和CRP均较术前显著性升高,3d时CRP达到峰值,7d时ESR达到高峰,此后逐渐下降;A组至术后56d时CRP降至造模前水平,84d时ESR降至造模前水平;B、C组至112d时CRP和ESR均仍显著性高于造模前水平(P0.05)。A组术后7d、56d、84d及112d的ESR和CRP均低于同时间点B、C组(P0.05),B组与C组同时间点无显著性差异(P0.05)。三组间术前和术后14d、28d、56d的肝、肾功能指标比较均无统计学差异(P0.05);三组术后14d、28d、56d的肝、肾功能指标与术前比较均无统计学差异(P0.05)。术后28d时A组心脏、肝脏、脾脏、脊髓及肾脏组织未见器质性改变及组织损伤征象。术后56d时A组植骨融合情况优于B组及C组(P0.05),骨-材料界面组织病理切片骨小梁面积显著性高于B组及C组(P0.01)。结论:HRZ缓释涂层在兔体内具有优良的抗结核性能和组织相容性。     

Genetic polymorphisms of NAT2 and CYP2E1 associated with antituberculosis drug-induced hepatotoxicity in Korean patients with pulmonary tuberculosis

Antituberculosis drug-induced hepatitis attributed to isoniazid (INH) is one of the most prevalent drug-induced liver injuries. INH is metabolized by hepatic N-acetyltransferase (NAT) and cytochrome P450 2E1 (CYP2E1) to form hepatotoxins. The aim of this study was to evaluate whether polymorphisms of the NAT2 and/or CYP2E1 genes were associated with antituberculosis drug-induced hepatotoxicity in Korean patients. A total of 132 patients with tuberculosis who received antituberculosis treatment were followed prospectively. Their NAT2 and CYP2E1 genotypes were determined using polymerase chain reaction (PCR) with or without sequencing. Eighteen (13.6%) patients developed antituberculosis drug-induced hepatotoxicity. Regarding NAT2, slow acetylators had a higher incidence of hepatotoxicity than rapid acetylators (36.8% vs. 9.7%, P=0.005) and there was a 3.8-fold risk of hepatotoxicity for the slow acetylators compared to the rapid acetylators. For the CYP2E1 gene, the RsaI polymorphism in the 5' untranslated region, and a polymorphic repetitive sequence at the CYP2E1 5'-flaking region were analyzed; there was no significant association between any CYP2E1 genotype and antituberculosis drug-induced hepatotoxicity. In conclusion, slow acetylator status of NAT2 was a significant susceptibility risk factor for antituberculosis drug-induced hepatotoxicity; NAT2 genotyping may be a useful tool for predicting antituberculosis drug-induced hepatotoxicity.     

Hepatoprotective Activity of Heptoplus on Isoniazid and Rifampicin Induced Liver Damage in Rats

The present study is designed to evaluate the efficacy of heptoplus a polyherbal formulation as an oral supplementary agent for isoniazid and rifampicin induced hepatotoxicity in rats. 50 and 100 mg/kg of heptoplus supplement were fed orally to the rats along with isoniazid and rifampicin and compared to rats treated with 100 mg/kg Liv 52 standard drug. Rats treated with isoniazid and rifampicin suffered from severe oxidative stress by the virtue of free radicals induced lipid per oxidation. As a result abnormal index of serum biochemical markers for liver function and increased liver lysosomal enzymes activity was observed. However rats nourished with 100 mg/kg of heptoplus and Liv 52 protected the liver from oxidative damage by maintaining normal antioxidant profile status and restored normal serum liver biochemical markers. Increased liver lysosomal enzymes activity is prevented in the rats supplemented with heptoplus and Liv 52. Histopathological analysis also revealed severe vascular changes and lobular necrosis in the treatment of isoniazid and rifampicin. Heptoplus (100 mg/kg) and Liv 52 supplemented rats liver apparently revealed normal architecture of liver. This study confirms that heptoplus has liver protective activity against Isoniazid and Rifampicin induced liver injury in rats, in par with Liv 52.     

Evaluation of Which Reactive Metabolite,If Any,Is Responsible for a Specific Idiosyncratic Reaction

Reactive metabolites are believed to be responsible for most idiosyncratic drug reactions. It is often assumed that if a reactive metabolite is found, it must be responsible for the idiosyncratic reactions associated with that drug. However, the evidence linking reactive metabolites and idiosyncratic reactions is circumstantial at best, and in many cases we have virtually no evidence. Furthermore, it is common for a drug to form several reactive metabolites, so it can be difficult to determine which, if any, is responsible for a given idiosyncratic reaction. Although the reactive metabolite hypothesis is logical, it has important implications for drug development, and we need to develop ways to test the hypothesis for specific drugs rigorously. Valid animal models are a powerful tool for testing whether a specific reactive metabolite is responsible for a specific adverse reaction and for studying further the mechanism by which it may induce such reactions; however, such models are rare.