Risk of gout flare after medication: prescription symmetry sequence analysis

OBJECTIVES

The research aimed to study the following questions: (1) five well-known gout-related medications were selected to test the validity of the prescription symmetry sequence analysis in Taiwan; (2) four exploratory medications were selected to test their relation to gout flares.

METHODS

We utilized the 2003-2017 dataset of the Taiwan National Health Insurance Program containing all claims data with 2 million beneficiaries as a data source. In order to explore the temporal association, we designed a scenario of medication-induced gout flares. Nine medications were selected as the index agent, including aspirin (low-dose), thiazide diuretics, loop diuretics, ethambutol, pyrazinamide, metformin, pioglitazone, fenofibrate, and losartan. The gout flare was defined as subjects with use of the marker agent for treatment of gout flares. The observation-window period between initiation of the index agent and initiation of the marker agent was 1 year. Subjects who used an index agent and a marker agent on the same day were excluded. The prescription symmetry sequence analysis was carried out to compare the observed number of persons who took an index agent prior to starting a marker agent with the observed number of persons who took a marker agent before starting an index agent. The adjusted sequence ratio (adjusted SR) with 95% confidence interval was applied to estimate the relation between an index agent and the marker agent.

RESULTS

Among five medications including aspirin (low-dose), thiazide diuretics, loop diuretics, ethambutol, and pyrazinamide, the adjusted sequence ratio ranged from 1.15 to 3.35 and all reached statistical significance. Fenofibrate use and losartan use were associated with a lower probability of gout flares, with reaching statistical significance (adjusted SR = 0.60 for fenofibrate and adjusted SR = 0.92 for losartan). Metformin use was associated with a greater probability of gout flares, with reaching statistical significance (adjusted SR = 1.14). Pioglitazone use did not reach statistical significance.

CONCLUSION

Based on the confirmatory analysis including five well-known gout-related medications, this study supports that the prescription symmetry sequence analysis can be used to detect an adverse drug event associated with one potential offending agent. The exposure to fenofibrate or losartan might be a protective factor against gout flares. Metformin use could be associated with a greater probability of gout flares, but this finding should be validated by other studies.

KEY POINTS

• What is already known about this subject? 1. The prescription symmetry sequence analysis is a useful method for detecting an adverse drug reaction associated with one potential offending drug. 2. Numerous medications are found to induce gout flares. • What does this study add? 1. The prescription symmetry sequence analysis supports the evidence that aspirin (low-dose), thiazide diuretics, loop diuretics, ethambutol and pyrazinamide are associated with a greater probability of gout flares. 2. The exposure to fenofibrate or losartan might be a protective factor against gout flares. 3. Metformin use could be associated with a greater probability of gout flares. • How might this impact on clinical practice or future developments? 1. Clinicians should always consider the possibility of medication-induced gout flares. If gout flares develop, discontinuation of risky medications is the first step. Then prescribing cascades can be eliminated.

Efficacy and safety of an innovative short-course regimen containing clofazimine for treatment of drug-susceptible tuberculosis: a clinical trial

In preclinical studies, a new antituberculosis drug regimen markedly reduced the time required to achieve relapse-free cure. This study aimed to preliminarily evaluate the efficacy and safety of this four-month regimen, consisting of clofazimine, prothionamide, pyrazinamide and ethambutol, with a standard six-month regimen in patients with drug-susceptible tuberculosis. An open-label pilot randomized clinical trial was conducted among the patients with newly diagnosed bacteriologically-confirmed pulmonary tuberculosis. The primary efficacy end-point was sputum culture negative conversion. Totally, 93 patients were included in the modified intention-to-treat population. The rates of sputum culture conversion were 65.2% (30/46) and 87.2% (41/47) for short-course and standard regimen group, respectively. There was no difference on two-month culture conversion rates, time to culture conversion, nor early bactericidal activity (P > 0.05). However, patients on short-course regimen were observed with lower rates of radiological improvement or recovery and sustained treatment success, which was mainly attributed to higher percent of patients permanently changed assigned regimen (32.1% vs. 12.3%, P = 0.012). The main cause for it was drug-induced hepatitis (16/17). Although lowering the dose of prothionamide was approved, the alternative option of changing assigned regimen was chosen in this study. While in per-protocol population, sputum culture conversion rates were 87.0% (20/23) and 94.4% (34/36) for the respective groups. Overall, the short-course regimen appeared to have inferior efficacy and higher incidence of hepatitis but desired efficacy in per-protocol population. It provides the first proof-of-concept in humans of the capacity of the short-course approach to identify drug regimens that can shorten the treatment time for tuberculosis.

Pharmacokinetics and safety of first-line tuberculosis drugs rifampin, isoniazid, ethambutol, and pyrazinamide during pregnancy and postpartum: results from IMPAACT P1026s

Physiological changes during pregnancy may alter the pharmacokinetics (PK) of antituberculosis drugs. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network P1026s was a multicenter, phase IV, observational, prospective PK and safety study of antiretroviral and antituberculosis drugs administered as part of clinical care in pregnant persons living with and without HIV. We assessed the effects of pregnancy on rifampin, isoniazid, ethambutol, and pyrazinamide PK in pregnant and postpartum (PP) persons without HIV treated for drug-susceptible tuberculosis disease. Daily antituberculosis treatment was prescribed following World Health Organization-recommended weight-band dosing guidelines. Steady-state 12-hour PK profiles of rifampin, isoniazid, ethambutol, and pyrazinamide were performed during second trimester (2T), third trimester (3T), and 2-8 of weeks PP. PK parameters were characterized using noncompartmental analysis, and comparisons were made using geometric mean ratios (GMRs) with 90% confidence intervals (CI). Twenty-seven participants were included: 11 African, 9 Asian, 3 Hispanic, and 4 mixed descent. PK data were available for 17, 21, and 14 participants in 2T, 3T, and PP, respectively. Rifampin and pyrazinamide AUC0-24 and C max in pregnancy were comparable to PP with the GMR between 0.80 and 1.25. Compared to PP, isoniazid AUC0-24 was 25% lower and C max was 23% lower in 3T. Ethambutol AUC0-24 was 39% lower in 3T but limited by a low PP sample size. In summary, isoniazid and ethambutol concentrations were lower during pregnancy compared to PP concentrations, while rifampin and pyrazinamide concentrations were similar. However, the median AUC0-24 for rifampin, isoniazid, and pyrazinamide met the therapeutic targets. The clinical impact of lower isoniazid and ethambutol exposure during pregnancy needs to be determined.

Molecular and cellular remodeling of HepG2 cells upon treatment with antitubercular drugs

Drug-induced liver injury (DILI) is an adverse outcome of the currently used tuberculosis treatment regimen, which results in patient noncompliance, poor treatment outcomes, and the emergence of drug-resistant tuberculosis. DILI is primarily caused by the toxicity of the drugs and their metabolites, which affect liver cells, biliary epithelial cells, and liver vasculature. However, the precise mechanism behind the cellular damage attributable to first-line antitubercular drugs (ATDs), as well as the effect of toxicity on the cell survival strategies, is yet to be elucidated. In the current study, HepG2 cells upon treatment with a high concentration of ATDs showed increased perforation within the cell, cuboidal shape, and membrane blebbing as compared with control/untreated cells. It was observed that ATD-induced toxicity in HepG2 cells leads to altered mitochondrial membrane permeability, which was depicted by the decreased fluorescence intensity of the MitoRed tracker dye at higher drug concentrations. In addition, high doses of ATDs caused cell damage through an increase in reactive oxygen species production in HepG2 cells and a simultaneous reduction in glutathione levels. Further, high dose of isoniazid (50-200 mM), pyrazinamide (50-200 mM), and rifampicin (20-100 µM) causes cell apoptosis and affects cell survival during toxic conditions by decreasing the expression of potent autophagy markers Atg5, Atg7, and LC3B. Thus, ATD-mediated toxicity contributes to the reduced ability of hepatocytes to tolerate cellular damage caused by altered mitochondrial membrane permeability, increased apoptosis, and decreased autophagy. These findings further emphasize the need to develop adjuvant therapies that can mitigate ATD-induced toxicity for the effective treatment of tuberculosis.

Treatment Strategy for Rifampin-Susceptible Tuberculosis

BACKGROUND

Tuberculosis is usually treated with a 6-month rifampin-based regimen. Whether a strategy involving shorter initial treatment may lead to similar outcomes is unclear.

METHODS

In this adaptive, open-label, noninferiority trial, we randomly assigned participants with rifampin-susceptible pulmonary tuberculosis to undergo either standard treatment (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks) or a strategy involving initial treatment with an 8-week regimen, extended treatment for persistent clinical disease, monitoring after treatment, and retreatment for relapse. There were four strategy groups with different initial regimens; noninferiority was assessed in the two strategy groups with complete enrollment, which had initial regimens of high-dose rifampin-linezolid and bedaquiline-linezolid (each with isoniazid, pyrazinamide, and ethambutol). The primary outcome was a composite of death, ongoing treatment, or active disease at week 96. The noninferiority margin was 12 percentage points.

RESULTS

Of the 674 participants in the intention-to-treat population, 4 (0.6%) withdrew consent or were lost to follow-up. A primary-outcome event occurred in 7 of the 181 participants (3.9%) in the standard-treatment group, as compared with 21 of the 184 participants (11.4%) in the strategy group with an initial rifampin-linezolid regimen (adjusted difference, 7.4 percentage points; 97.5% confidence interval [CI], 1.7 to 13.2; noninferiority not met) and 11 of the 189 participants (5.8%) in the strategy group with an initial bedaquiline-linezolid regimen (adjusted difference, 0.8 percentage points; 97.5% CI, -3.4 to 5.1; noninferiority met). The mean total duration of treatment was 180 days in the standard-treatment group, 106 days in the rifampin-linezolid strategy group, and 85 days in the bedaquiline-linezolid strategy group. The incidences of grade 3 or 4 adverse events and serious adverse events were similar in the three groups.

CONCLUSIONS

A strategy involving initial treatment with an 8-week bedaquiline-linezolid regimen was noninferior to standard treatment for tuberculosis with respect to clinical outcomes. The strategy was associated with a shorter total duration of treatment and with no evident safety concerns. (Funded by the Singapore National Medical Research Council and others; TRUNCATE-TB ClinicalTrials.gov number, NCT03474198.).

Pyrazinamide related prolonged drug-induced liver injury: A case report

RATIONALE

Drug induced liver injury (DILI) is a common side effect causing treatment discontinuation during tuberculosis (TB) treatment, and pyrazinamide (PZA) usually leads to a delayed and prolonged abnormal liver function of the 4 standard anti-tuberculosis regimens. However, a prolonged hepatitis lasting more than 4 months is rarely reported.

PATIENT CONCERNS

A 78-year-old man presented with general weakness and poor appetite on his seventh week of anti-TB treatment for tuberculosis lymphadenitis.

DIAGNOSIS

Drug induced liver injury, PZA-related. NAT2 slow acetylator phenotype was accidentally found during workup of DILI.

INTERVENTION

A liver biopsy was performed and PZA-related DILI was suspected. All anti-TB medications were therefore discontinued.

OUTCOME

After withholding all anti-TB medications for 4 months, the elevations of aminotransferases and hyperbilirubinemia completely resolved. Anti-TB therapy was switched to ethambutol and levofloxacin for 15 months without adverse events. Long-term ultrasound follow-up was performed and cervical lymphadenopathy completely resolved.

CONCLUSION

Our patient presents with PZA related prolonged DILI resolved after drug discontinuation for 4 months. NAT2 slow acetylator phenotype may be related to this condition through unknown mechanisms.

Ameliorative potential of Adhatoda vasica against anti-tubercular drugs induced hepatic impairments in female Wistar rats in relation to oxidative stress and xeno-metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Adhatoda vasica Nees is widely used herb of indigenous system to treat various ailments especially upper respiratory tract infections. Not only, anti-tubercular efficacy of crude extract and phytoconstituents of A. vasica has been documented but its hepatoprotective role against various drugs mediated hepatic alterations in different animal models has also been observed.

BACKGROUND AND PURPOSE

Isoniazid, rifampicin and pyrazinamide (H-R-Z) are anti-tubercular drugs normally prescribed by health professionals for the treatment of tuberculosis, however along with their medical effectiveness these drugs also exhibit hepatotoxicity among TB patients. Unexpectedly, substantial toxicological data on the metabolism of anti-TB drugs are available but the mystery behind these xenobiotics is too complex and partly implicit. In this study, we further explored the hepatotoxic effects of these xeno-metabolic products and their amelioration by Adhatoda vasica Nees by elucidating its mechanistic action.

METHODS

We generated a hepatotoxic rodent model by oral administration of H, R and Z (30.85, 61.7 and 132.65 mg/kg body weight) drugs for 25 days in Wistar rats. Additionally, to achieve hepatoprotection two different doses of Adhatoda vasica Nees ethanolic leaf extract (200 and 300 mg/kg body weight) were used along with H-R-Z dosage, orally and once daily for 25 days and tried to ascertain their mechanistic action. For this, initially phytoconstituents of the extract were evaluated followed by extract standardization using RP-HPLC and FTIR methods. Furthermore, antioxidant activity of the extract was analyzed by DPPH assay. Finally, different treated groups were analyzed for hepatic oxidative stress markers, antioxidant markers, histopathological changes and gene expression study including CYP2E1, CYP7A1, NAT, NR1I2 and UGT1A1 genes involved in phase I and phase II xeno-metabolism.

RESULTS

Estimated content of vasicine in RP-HPLC method and free-radical scavenging activity in DPPH assay was found to be 134.519 ± 0.00269μg/10mg of leaf extract and 47.81 μg/mL respectively. In H-R-Z treated group, a significant increase in the levels of thiobarbituric acid, significant reduction in the levels of GSH, and enzymatic markers and marked changes in hepatic histological architecture were observed. In addition, there was significance up-regulation of CYP7A and NAT genes, down-regulation of CYP2E1 gene and insignificant expression levels of NR1I2 and UGT1A1 genes were observed in H-R-Z group. Conversely, high dose of A. vasica extract effectively diminished these alterations by declining oxidative stress and boosting of antioxidant levels. In addition, it acted as bi-functional inducer of both phase I (CYP2E1) and phase II (NAT and UGT1A1) enzyme systems.

CONCLUSION

Hence, we concluded that anti-TB drugs exposure has potential to generate reactive metabolites that eventually cause hepatotoxicity by altering oxidant-antioxidant levels and their own metabolism. This study not only emphasized on xeno-metabolism mediated hepatic alterations but also explore the benefit of A. vasica on these toxic insults.

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

Background

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

Methods

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

Results

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

Conclusion

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

Efficacy Versus Hepatotoxicity of High-dose Rifampin, Pyrazinamide, and Moxifloxacin to Shorten Tuberculosis Therapy Duration: There Is Still Fight in the Old Warriors Yet!

Background

One approach that could increase the efficacy and reduce the duration of antituberculosis therapy is pharmacokinetics/pharmacodynamics-based optimization of doses. However, this could increase toxicity.

Methods

We mimicked the concentration-time profiles achieved by human equivalent doses of moxifloxacin 800 mg/day, rifampin 1800 mg/day, and pyrazinamide 4000 mg/day (high-dose regimen) vs isoniazid 300 mg/day, rifampin 600 mg/day, and pyrazinamide 2000 mg/day (standard therapy) in bactericidal and sterilizing effect studies in the hollow fiber system model of tuberculosis (HFS-TB). In an intracellular Mycobacterium tuberculosis (Mtb) HFS-TB experiment, we added a 3-dimensional human organotypic liver to determine potential hepatotoxicity of the high-dose regimen, based on lactate dehydrogenase (LDH). Treatment lasted 28 days and Mtb bacterial burden was based on colony counts. We calculated the time to extinction (TTE) of the Mtb population in the HFS-TB and used morphism-based transformation and Latin hypercube sampling to identify the minimum therapy duration in patients.

Results

The kill rate of standard therapy in the bactericidal effect and sterilizing effect experiments were 0.97 (95% confidence interval [CI], .91-.99) log10 colony-forming units (CFU)/mL/day, and 0.56 (95% CI, .49-.59) log10 CFU/mL/day, respectively. The high-dose regimen's bactericidal and sterilizing effect kill rates were 0.99 (95% CI, .96-.99) log10 CFU/mL/day and 0.72 (95% CI, .56-.79) log10 CFU/mL/day, respectively. The upper confidence bound for TTE in patients was 4.5-5 months for standard therapy vs 3.7 months on the high-dose regimen. There were no differences in LDH concentrations between the 2 regimens at any time point (P > .05).

Conclusions

The high-dose regimen may moderately shorten therapy without increased hepatotoxicity compared to standard therapy.

Longitudinal profiling reveals a persistent intestinal dysbiosis triggered by conventional anti-tuberculosis therapy

BACKGROUND

Effective treatment of Mycobacterium tuberculosis (Mtb) infection requires at least 6 months of daily therapy with multiple orally administered antibiotics. Although this drug regimen is administered annually to millions worldwide, the impact of such intensive antimicrobial treatment on the host microbiome has never been formally investigated. Here, we characterized the longitudinal outcome of conventional isoniazid-rifampin-pyrazinamide (HRZ) TB drug administration on the diversity and composition of the intestinal microbiota in Mtb-infected mice by means of 16S rRNA sequencing. We also investigated the effects of each of the individual antibiotics alone and in different combinations.

RESULTS

While inducing only a transient decrease in microbial diversity, HRZ treatment triggered a marked, immediate and reproducible alteration in community structure that persisted for the entire course of therapy and for at least 3 months following its cessation. Members of order Clostridiales were among the taxa that decreased in relative frequencies during treatment and family Porphyromonadaceae significantly increased post treatment. Experiments comparing monotherapy and different combination therapies identified rifampin as the major driver of the observed alterations induced by the HRZ cocktail but also revealed unexpected effects of isoniazid and pyrazinamide in certain drug pairings.

CONCLUSIONS

This report provides the first detailed analysis of the longitudinal changes in the intestinal microbiota due to anti-tuberculosis therapy. Importantly, many of the affected taxa have been previously shown in other systems to be associated with modifications in immunologic function. Together, our findings reveal that the antibiotics used in conventional TB treatment induce a distinct and long lasting dysbiosis. In addition, they establish a murine model for studying the potential impact of this dysbiosis on host resistance and physiology.

Gitelman-like Syndrome with Kanamycin Toxicity

A 22 year-old lady with multi-drug-resistant pulmonary tuberculosis was on Kanamycin, Cycloserine, Ethionamide, Pyrazinamide and Moxifloxacin since more than two months. She presented with muscle cramps and carpopedal spasm. Investigation revealed hypokalemia and metabolic alkalosis. She also had hypomagnesemia, hypochloremia and hypocalciuria. Serum urea and creatinine levels were normal. Patient was treated with intravenous and oral potassium chloride. Kanamycin was stopped. Metabolic alkalosis and hypokalemia improved gradually over one month. Biochemical parameters were like Gitelman's syndrome but it reversed with stoppage of Kanamycin. Gitelman-like syndrome with Kanamycin toxicity has not been reported in literature previously.

Ameliorative Effects of Kolaviron, a Biflavonoid Fraction from Garcinia Kola Seed, on Hepato-renal Toxicity of Anti-tuberculosis Drugs in Wistar Rats

BACKGROUND

Tuberculosis (TB) is an infectious disease of international health priority. The combination of anti-TB drugs (4-Tabs)- isoniazid (INH), rifampicin (RIF), pyrazinamide (PZA) and ethambutol (ETB) are effective in the management of the disease, however, their toxic effect is a major concern.

PURPOSE

The study was designed to evaluate the toxicity of anti-TB drugs in male Wistar rats and possible ameliorative effects of kolaviron (KV), a biflavonoid from Garcinia kola seeds.

METHODS

Twenty-eight rats were assigned into four groups; Group 1 (Control) received corn oil, Group 2 (4-Tabs) received therapeutic doses of INH (5 mg/kg), RIF (10 mg/kg), PZA (15 mg/kg) and ETB (15 mg/kg) in combination, Group 3 (4-Tabs + KV) received INH, RIF, PZA, ETB and KV (200 mg/kg) and Group 4 (KV) received KV (200 mg/kg) by oral gavage three times per week for 8 consecutive weeks.

RESULTS

Administration of 4-Tabs caused oxidative stress resulting in significant (p = 0.031, 0.027) increase in malondialdehyde levels in the liver and kidney of rats by 101% and 34%, respectively. Also, 4-Tabs caused significant (p = 0.023-0.035) elevation of serum alanine and aspartate aminotransferases by 41% and 48%, creatinine by 252% and total bilirubin by 89%, respectively. In contrast, hepatic and renal antioxidant indices- reduced glutathione, glutathione peroxidase, glutathione-s-transferase and superoxide dismutase were significantly (p = 0.028-0.039) decreased in 4-Tabs-treated rats. Co-administration of KV with 4-Tabs significantly restored the antioxidant parameters and biochemical indices to near normal.

CONCLUSION

These findings suggest that anti-TB drugs elicit oxidative damage in liver and kidney of rats while KV protects against the adverse effects via antioxidative mechanism.

Drug-induced myopathy in a patient with pulmonary tuberculosis

A 26-year-old man, who had started treatment for pulmonary tuberculosis, developed polyarthralgia, generalised myalgia, weakness, and elevated uric acid and creatine kinase levels. His polyarthralgia improved on cessation of pyrazinamide, but the improvement in his myalgia and creatine kinase was delayed. Drug-induced myopathy was considered as there were no clear alternative explanations.

[DRUG-INDUCED LIVER INJURY AND PYRAZINAMIDE USE]

BACKGROUND

In the 1950s, high doses (40-70 mg/kg/day) of pyrazinamide were reported to cause drug-induced liver injury (DILI). It remains unclear whether adding pyrazinamide (Z) at the currently accepted low dose (20-25 mg/kg/day) to a regimen of isoniazid (H), rifampicin (R), and ethambutol (E) increases the risk of DILI.

METHOD

We reviewed adult patients admitted for smear-positive tuberculosis who were treated with a daily HRE or HRZE regimen. A Cox model was used to analyze the impact of pyrazinamide on the occurrence of DILI.

RESULTS

We reviewed 195 patients (123 men [63%], 72 women [37%], average age 65 ± 19 years, 65 HRE patients [33%], 130 HRZE patients [67%]). The incidence of DILI in the first two months was 15% (29/195). The HRZE regimen was not associated with DILI (hazard ratio 0.55, P = 0.263).

CONCLUSION

Addition of low-dose (20-25 mg/kg/day) pyrazinamide to the HRE regimen does not appeared to be associated with increased DILI incidence during the first two months of treatment.

Pyridoxine induced rosacea-like dermatitis

Rosacea is a common chronic inflammatory cutaneous disease of unknown etiology, characterized by remissions and exacerbations, presenting with centrofacial erythema and telangiectasias. It affects mainly adults around the age of 30 years and classically predominates in females. The pathophysiology of rosacea has not yet been fully understood. Risk factors are positive family history, very light skin phototype, sun exposure and consumption of spicy food or alcohol. Recently, there has been some evidence that some drugs or vitamins could be potential factors that can aggravate rosacea or induce rosacea-like symptoms. In this context, we present a 53-year-old female developing rosacea-like dermatitis due to a fixed combination of isoniazid and pyridoxine, which she was receiving along with rifampicin for the treatment of pulmonary tuberculosis.

Drug-induced hepatotoxicity of anti-tuberculosis drugs and their serum levels

The correlation between serum anti-tuberculosis (TB) drug levels and the drug-induced hepatotoxicity (DIH) remains unclear. The purpose of this study was to investigate whether anti-TB DIH is associated with basal serum drug levels. Serum peak levels of isoniazid (INH), rifampicin (RMP), pyrazinamide (PZA), and ethambutol (EMB) were analyzed in blood samples 2 hr after the administration of anti-TB medication. Anti-TB DIH and mild liver function test abnormality were diagnosed on the basis of laboratory and clinical criteria. Serum anti-TB drug levels and other clinical factors were compared between the hepatotoxicity and non-hepatotoxicity groups. A total of 195 TB patients were included in the study, and the data were analyzed retrospectively. Seventeen (8.7%) of the 195 patients showed hepatotoxicity, and the mean aspartate aminotransferase/alanine aminotransferase levels in the hepatotoxicity group were 249/249 IU/L, respectively. Among the 17 patients with hepatotoxicity, 12 showed anti-TB DIH. Ten patients showed PZA-related hepatotoxicity and 2 showed INH- or RMP-related hepatotoxicity. However, intergroup differences in the serum levels of the 4 anti-TB drugs were not statistically significant. Basal serum drug concentration was not associated with the risk anti-TB DIH in patients being treated with the currently recommended doses of first-line anti-TB treatment drugs.

Currently Used Low-Dose Pyrazinamide Does Not Increase Liver-Injury in the First Two Months of Tuberculosis Treatment

OBJECTIVE

In the 1950s, a high-dose (40-70 mg/kg/day) of pyrazinamide (PZA), was reported to cause drug-induced liver injury (DILI) at an unacceptable frequency. It remains unclear whether adding PZA (Z) at the currently accepted low-dose (20-25 mg/kg/day) for two months to a regimen of isoniazid (H) + rifampicin (R) + ethambutol (E) actually increases the risk of DILI.

METHOD

Smear-positive tuberculosis patients were treated with daily HRE or HRZE regimen under direct observation. We used three independent models. Model 1 was analyzed with a multivariate Cox-analysis using a pre-matched cohort. Next, propensity score matching was conducted using the nearest neighbor method with caliper of 0.03. Models 2 and 3 were analyzed by univariate and multivariate Cox-analyses, respectively, with the matched cohort. DILI was assessed based on the guidelines of the American Thoracic Society.

RESULTS

We reviewed the records of 383 patents (male, n=260; female n=123; mean age, 64±20 years). Among these patients, 75 patients were treated with HRE and 308 were treated with HRZE. DILI occurred in the first two months in 24% (18/75) and 8% (24/308) of the HRE-treated and HRZE-treated cases, respectively. In all three of the models, DILI was less frequent in patients treated with the HRZE regimen: Model 1, HR of 0.30 (95% confidence interval (CI) 0.14-0.68, p=0.004); Model 2, HR of 0.37 (95%CI 0.14-0.96, p=0.041); and Model 3, HR of 0.34 (95%CI 0.12-0.94, p=0.038).

CONCLUSION

The addition of the currently accepted low dose (20-25 mg/kg/day) of PZA to the HRE regimen did not increase the incidence of DILI during the first two months of treatment.

[Hypothermia due to anti-tuberculosis drugs: first case]

Hypothermia - an adverse reaction of drug use potentially severe - requires an early diagnosis and an adapted management. We report the first case, to our knowledge of hypothermia due to anti-tuberculosis drugs.

Profile of adverse drug reactions in drug resistant tuberculosis from Punjab

OBJECTIVE

The aim of the study was to elucidate the profile of adverse drug reactions (ADRs) associated with second-line anti-tubercular treatment for drug-resistant tuberculosis.

MATERIAL AND METHODS

ADR profile of diagnosed drug-resistant tuberculosis cases on supervised second-line anti-tubercular drug regimen under Programmatic Management of Drug-resistant Tuberculosis under Revised National Tuberculosis Control Programme, were studied over two years' period. Adverse reactions were categorised into mild, moderate and severe types with subsequent systematic data-analysis.

RESULTS

Out of total 207 patients in the study, 81.16% reported with adverse drug reactions. Out of total 195 adverse events, 63.58%, 18.46% and 17.94% were of mild, moderate and severe types respectively. Gastrointestinal events, hepatitis, hearing impairment, arthralgia, psychosis, hypothyroidism, visual disturbances, giddiness, peripheral neuropathy, skin reactions, swelling or pain at injection site, anorexia and sleep disturbances were important amongst these. High proportion of drug and/or alcohol abuse was an important observation. The offending drug(s) had to be terminated in 12.08% of the patients.

CONCLUSION

Early detection, management and pharmaco-vigilance reporting of ADRs remain key factors in the management of drug-resistant tuberculosis with remarkable relevance of the need for early diagnosis and treatment of 'drug-sensitive tuberculosis', to prevent emergence of drug-resistant tuberculosis.

The incidence of liver injury in Uyghur patients treated for TB in Xinjiang Uyghur autonomous region, China, and its association with hepatic enzyme polymorphisms nat2, cyp2e1, gstm1 and gstt1

Background and Objective

Of three first-line anti-tuberculosis (anti-TB) drugs, isoniazid is most commonly associated with hepatotoxicity. Differences in INH-induced toxicity have been attributed to genetic variability at several loci, NAT2, CYP2E1, GSTM1and GSTT1, that code for drug-metabolizing enzymes. This study evaluated whether the polymorphisms in these enzymes were associated with an increased risk of anti-TB drug-induced hepatitis in patients and could potentially be used to identify patients at risk of liver injury.

Methods and Design

In a cross-sectional study, 2244 tuberculosis patients were assessed two months after the start of treatment. Anti-TB drug-induced liver injury (ATLI) was defined as an ALT, AST or bilirubin value more than twice the upper limit of normal. NAT2, CYP2E1, GSTM1 and GSTT1 genotypes were determined using the PCR/ligase detection reaction assays.

Results

2244 patients were evaluated, there were 89 cases of ATLI, a prevalence of 4% 9 patients (0.4%) had ALT levels more than 5 times the upper limit of normal. The prevalence of ATLI was greater among men than women, and there was a weak association with NAT2*5 genotypes, with ATLI more common among patients with the NAT2*5*CT genotype. The sensitivity of the CT genotype for identifying patients with ATLI was 42% and the positive predictive value 5.9%. CT ATLI was more common among slow acetylators (prevalence ratio 2.0 (95% CI 0.95,4.20) )compared to rapid acetylators. There was no evidence that ATLI was associated with CYP2E1 RsaIc1/c1genotype, CYP2E1 RsaIc1/c2 or c2/c2 genotypes, or GSTM1/GSTT1 null genotypes.

Conclusions

In Xinjiang Uyghur TB patients, liver injury was associated with the genetic variant NAT2*5, however the genetic markers studied are unlikely to be useful for screening patients due to the low sensitivity and low positive predictive values for identifying persons at risk of liver injury.

L’intérêt de l’accoutumance aux antituberculeux majeurs

Les réactions d’ hypersensibilité aux antituberculeux sont relativement rares et graves par leur caractère imprévisible, elles conduisent généralement à l'arrêt ou au changement thérapeutique. Nous rapportons un cas d'hypersensibilité à trois antibacillaires majeurs (Isoniazide, Pyrazinamide, Ethombutol). Une accoutumance orale à ces trois médicaments a été réalisée permettant à la patiente de bénéficier d'un traitement antibacillaire optimal.

[A clinical investigation of seven patients with pulmonary tuberculosis who developed mixed liver injury during oral anti-tuberculosis treatment]

BACKGROUND

Liver injury is the most common and clinically significant adverse reaction to anti-tuberculosis drugs, sometimes resulting in a fatal outcome. It has been reported that liver injury induced by isoniazid and pyrazinamide, which has the potential to cause hepatocellular injury, has a risk of becoming severe; while an injury induced by rifampicin, which has the potential to cause cholestatic injury, rarely becomes severe. However, mixed liver injury has not been studied thoroughly.

METHODS

Of 321 tuberculosis patients who were admitted and treated in our hospital over the past 5 years, 7 patients (2.1 %) who developed mixed liver injury due to the use of antituberculosis drugs were clinically investigated through their medical records.

RESULTS

There were 4 male patients and 3 female patients, with a mean age of 66.7 (59-85) years. The mean duration from the start of oral anti-tuberculosis drugs to the onset of mixed liver injury was 28.5 days. In 2 of the patients, the event occurred within 2 weeks. Two of them had a total bilirubin level of > 5 mg/dl at the time of diagnosis. In 6 of the 7 patients, the liver injury improved on discontinuation of the anti-tuberculosis drugs. In the remaining 1 patient, the liver injury progressed even after discontinuation of the oral treatment, leading to death.

CONCLUSION

Since mixed liver injury sometimes results in a fatal outcome, it is necessary to take adequate precautions.

A case of thrombocytopenia caused by rifampicin and pyrazinamide

A 32-year-old male patient was diagnosed as having pulmonary tuberculosis and put on category II antitubercular regime since he had a history of antituberculosis treatment 10 years ago. Within 3 weeks, patient presented with ulcers in mouth, and blood picture confirmed thrombocytopenia. Rifampicin-induced thrombocytopenia was suspected and antitubercular treatment stopped. Patient improved and was re-exposed to the drugs one by one. After re-exposure with pyrazinamide, the platelet count decreased drastically and oral mucosal ecchymoses reappeared, while with rifampicin, thrombocytopenia was accompanied with petechiae on legs and forearms. Isoniazid, ethambutol, and streptomycin were continued.

[Comparison of drug-induced hepatitis occurring in elderly and younger patients during anti-tuberculosis treatment with a regimen including pyrazinamide]

BACKGROUND

In Japan, tuberculosis (TB) patients aged over 80 years are usually treated with a regimen not including pyrazinamide (PZA) because of the risk of drug-induced hepatitis.

PURPOSES

The purpose of this study was to investigate the occurrence of drug-induced hepatitis in TB patients over 80 years of age, who are treated with a regimen including PZA, and compare the findings with those of younger patients. [Methods] Thirty-six patients with pulmonary tuberculosis, who were admitted to Yokohama City University Hospital between June 2011 and March 2012 were included. They were treated with isoniazid, rifampicin, ethambutol, and PZA and had their liver function assessed once a week for 2 months.

RESULTS

Hepatitis occurred in 4 of 28 (14.3%) patients aged under 80 years and in 1 of 8 (12.5%) patients aged over 80 years.

CONCLUSION

There was no difference in the frequency of drug-induced hepatitis between patients aged under and over 80 years. We conclude that elderly patients aged over 80 years should be treated with a short course regimen that includes PZA.

14-day bactericidal activity of PA-824, bedaquiline, pyrazinamide, and moxifloxacin combinations: a randomised trial

BACKGROUND

New drugs, but also shorter, better-tolerated regimens are needed to tackle the high global burden of tuberculosis complicated by drug resistance and retroviral disease. We investigated new multiple-agent combinations over the first 14 days of treatment to assess their suitability for future development.

METHODS

In this prospective, randomised, early bactericidal activity (EBA) study, treatment-naive, drug-susceptible patients with uncomplicated pulmonary tuberculosis were admitted to hospitals in Cape Town, South Africa, between Oct 7, 2010, and Aug 19, 2011. Patients were randomised centrally by computer-generated randomisation sequence to receive bedaquiline, bedaquiline-pyrazinamide, PA-824-pyrazinamide, bedaquiline-PA-824, PA-824-moxifloxacin-pyrazinamide, or unmasked standard antituberculosis treatment as positive control. The primary outcome was the 14-day EBA assessed in a central laboratory from the daily fall in colony forming units (CFU) of M tuberculosis per mL of sputum in daily overnight sputum collections. Bilinear regression curves were fitted for each group separately and groups compared with ANOVA for ranks, followed by pair-wise comparisons adjusted for multiplicity. Clinical staff were partially masked but laboratory personnel were fully masked. This study is registered, NCT01215851.

FINDINGS

The mean 14-day EBA of PA-824-moxifloxacin-pyrazinamide (n=13; 0·233 [SD 0·128]) was significantly higher than that of bedaquiline (14; 0·061 [0·068]), bedaquiline-pyrazinamide (15; 0·131 [0·102]), bedaquiline-PA-824 (14; 0·114 [0·050]), but not PA-824-pyrazinamide (14; 0·154 [0·040]), and comparable with that of standard treatment (ten; 0·140 [0·094]). Treatments were well tolerated and appeared safe. One patient on PA-824-moxifloxacin-pyrazinamide was withdrawn because of corrected QT interval changes exceeding criteria prespecified in the protocol.

INTERPRETATION

PA-824-moxifloxacin-pyrazinamide is potentially suitable for treating drug-sensitive and multidrug-resistant tuberculosis. Multiagent EBA studies can contribute to reducing the time needed to develop new antituberculosis regimens.

FUNDING

The Global Alliance for TB Drug Development (TB Alliance).

[Therapeutic approach in a case of allergic reaction to antituberculosis drugs -- a case report]

Medicaton used to treat tuberculosis is responsible for numerous side effects that have a major impact on patient's health, with a negative influence on the quality of life. Patients of all ages must be trained in order to recognize all the adverse effects and the undesirable reactions produced by antituberculosis medication. We report the case of a 24-year-old woman with generalized psoriasis and psoriatic arthropathy who was treated against tuberculosis. After 7 days of treatment with isoniazid, rifampicin, ethambutol and pyrazinamid she had severe allergic reaction with generalized pruritus and rash which were difficult to control with antiallergic treatment.

CONCLUSIONS

Particular to this case is the absence in patient's history of the allergic reactions to medication. The re-establishment of treatment of tuberculosis was done by clinical trials and the patient had responded to only three drugs: isoniazid, rifampicin and ofloxacin, so the patient received an individual treatment due to adverse reactions to tuberculosis medications.

[Directly observed treatment for tuberculosis in a Buenos Aires City hospital]

The outcomes of directly observed therapy of tuberculosis (DOT) between 1/1/1979 and 12/31/2009 were analyzed. Results obtained in the 1979-1999 period were compared with those achieved in the 2000-2009 period. In a Buenos Aires City hospital, 582 HIV negative TB patients received rifampin, isoniazid, pyrazinamide and ethambutol or streptomycin in the initial stage, followed by a second stage where patients were included in two groups: G1 composed by 424 patients (period 1/1/1979-12/31/1999) who received either rifampin and isoniazid or rifampin and streptomicin twice a week, and G2, with 158 patients (period 1/1/2000-12/31/2009) who received either rifampin and isoniazid twice or three times a week. National and Buenos Aires City TB Control Programs recommendations were followed. Patients who underwent DOT had higher completeness rates than those included in self-administered therapy (82.8% vs. 48.7%), (p <0.0001). Mean age: 36.3 ± 15.3 years, males: 63.1% and 69.4% were Argentine citizens. A 8.9% had been previously treated, 6.1% had co-morbidities. A 70.6% of pulmonary cases was bacteriologically confirmed, 82.8% of them completed the treatment, while 11.5% defaulted. Adverse effects to antituberculosis drugs were observed in 9.5% of cases; male patients showed higher rates of non adherence. G2 had a lower proportion of native people (48.7% vs. 77.1%), (p = 0.0001), higher frequency of co-morbidities (10.7% vs. 4.4%), (p = 0.005), of bacteriologically confirmed pulmonary cases (95% vs. 87%), (p = 0.02) and more adverse effects than G1 (17% vs. 6.6%), (p = 0.0001). In coincidence with other experiences, this work shows high treatment success rates in patients treated under DOT strategy.

Efficacy and safety of a 4-drug fixed-dose combination regimen compared with separate drugs for treatment of pulmonary tuberculosis: the Study C randomized controlled trial

CONTEXT

Fixed-dose combinations (FDCs) of drugs for treatment of tuberculosis have been advocated to prevent the emergence of drug resistance.

OBJECTIVE

To assess the efficacy and safety of a 4-drug FDC for the treatment of tuberculosis.

DESIGN, SETTING, AND PATIENTS

The Study C trial, a parallel-group, open-label, noninferiority, randomized controlled trial conducted in 11 sites in Africa, Asia, and Latin America between 2003 and 2008. Patients were 1585 adults with newly diagnosed smear-positive pulmonary tuberculosis.

INTERVENTIONS

Patients were randomized to receive daily treatment with 4 drugs (rifampicin, isoniazid, pyrazinamide, ethambutol) given as an FDC (n = 798 patients) or separately (n = 787) in the 8-week intensive phase of treatment.

MAIN OUTCOME MEASURE

Favorable treatment outcome, defined as negative culture result at 18 months post randomization and not having already been classified as unfavorable. Noninferiority was dependent on consistent results from a per-protocol and modified intention-to-treat analysis, using 2 different models for the latter, classifying all changes of treatment or refusal to continue treatment (eg, bacteriological failure/relapse, adverse event, default, drug resistance) as unfavorable (model 1) and classifying changes of treatment for reasons other than therapeutic outcomes according to their 18-month bacteriological outcome if available (post hoc model 2). The prespecified noninferiority margin was 4%.

RESULTS

In the per-protocol analysis, 555 of 591 patients (93.9%) had a favorable outcome in the FDC group vs 548 of 579 (94.6%) in the separate-drugs group (risk difference, -0.7% [90% confidence interval {CI}, -3.0% to 1.5%]). In the model 1 analysis, 570 of 684 patients (83.3%) had a favorable outcome in the FDC group vs 563 of 664 (84.8%) in the separate-drugs group (risk difference, -1.5% [90% CI, -4.7% to 1.8%]). In the post hoc model 2 analysis, 591 of 658 patients (89.8%) in the FDC group and 589 of 647 (91.0%) in the separate-drugs group had a favorable outcome (risk difference, -1.2% [90% CI, -3.9% to 1.5%]). Adverse events related to trial drugs were similarly distributed among treatment groups.

CONCLUSIONS

Compared with a regimen of separately administered drugs, a 4-drug FDC regimen for treatment of tuberculosis satisfied prespecified noninferiority criteria in 2 of 3 analyses. Although the results do not demonstrate full noninferiority of the FDCs compared with single drugs given separately using the strict definition applied in this trial, use of FDCs is preferred because of potential advantages associated with the administration of FDCs compared with separate-drug formulations.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00216333.

Torticollis in mice intravenously infected with Mycobacterium tuberculosis

Female BALB/cAnNCrl (n = 170; age, 6 to 9 wk) mice were infected by intravenous inoculation of 5 × 10(6) cfu Mycobacterium tuberculosis strain Erdman (ATCC 35801). Between day 52 and 5 mo after infection, 10 of the 170 mice infected according to this protocol developed torticollis, including mice in treatment groups that received combination antibiotic therapy of rifampin-pyrazinamide or moxifloxacin-rifampin-pyrazinamide. Torticollis did not develop in mice receiving isoniazid- rifampin-pyrazinamide therapy, nor was it present in the cohort of aerogenically infected mice. Affected mice were euthanized, and complete necropsy evaluation was performed on 4 mice. Gross necropsy evaluation revealed typical tuberculosis lesions in lungs of infected mice. Histologic evaluation of tissues revealed granulomatous otitis media with intralesional acid-fast bacilli consistent with Mycobacterium tuberculosis. These cases represent an unusual finding specific to the intravenous mouse model of Mycobacterium tuberculosis and may represent a model of a similar condition in humans that is known as tuberculous otitis media.

NAT2 and CYP2E1 polymorphisms and susceptibility to first-line anti-tuberculosis drug-induced hepatitis

BACKGROUND

Most cases with anti-tuberculosis drug-induced hepatotoxicity (ATDH) have been attributed to isoniazid.

OBJECTIVE

To evaluate whether the polymorphisms of the cytochrome P450 2EI (CYP2E1) and N-acetyltransferase 2 (NAT2) gene are associated with ATDH.

DESIGN

A total of 140 tuberculosis (TB) patients without liver diseases before treatment who received anti-tuberculosis treatment were followed prospectively. Their CYP2E1 and NAT2 genotypes were determined using the TaqMan polymerase chain reaction assay.

RESULTS

Forty-five (32.1%) patients were diagnosed with ATDH. No significant differences were reported in age and sex between patients with and without ATDH. Slow acetylators defined by NAT2 genotypes had a higher risk of hepatotoxicity than rapid acetylators (51.2% vs. 25.2%, P = 0.0026). Odds ratio (OR) analysis showed that slow acetylator status (OR 3.15, 95%CI 1.47-6.48) was the only independent risk factor for ATDH. Pyrazinamide co-administration induced hepatitis was also associated with NAT2 acetylator status. CYP2E1 c1/c1 homozygotes are prone to developing more severe hepatotoxicity than other c1/c2 and c2/c2 genotypes.

CONCLUSION

The slow acetylator status of NAT2 is a significant susceptibility risk factor for ATDH. CYP2E1 is associated with the severity of ATDH.

Safety of 3 different reintroduction regimens of antituberculosis drugs after development of antituberculosis treatment-induced hepatotoxicity

BACKGROUND

Drug-induced hepatotoxicity (DIH) is the most common adverse drug reaction leading to interruption of antituberculosis treatment. Worldwide, different reintroduction regimens have been advocated, but no consensus guidelines are available. Reintroduction of antituberculosis drugs in patients with DIH has never been studied systematically. We aimed to compare the safety of 3 different reintroduction regimens of antituberculosis drugs in patients with antituberculosis DIH.

METHODS

A total of 175 patients with a diagnosis of antituberculosis DIH were randomized to receive 1 of 3 different predefined reintroduction regimens of antituberculosis drugs and were evaluated prospectively. Patients in arm I were given isoniazid, rifampicin, and pyrazinamide simultaneously at full dosage from day 1. In arm II, drugs were administered in a manner similar to that recommended in the American Thoracic Society guidelines for reintroduction. In arm III, drugs were administered in accordance with British Thoracic Society guidelines.

RESULTS

Nineteen patients (10.9%) had recurrence of DIH during follow-up. Eight, 6, and 5 patients had recurrence of hepatitis in arms I, II, and III, respectively (P = .69). Of all the clinical and laboratory parameters, pretreatment serum albumin level was the only statistically significant predictor of future recurrence of DIH on reintroduction of antituberculosis drugs (P < .01).

CONCLUSIONS

The recurrence rate of hepatotoxicity was not significantly different between the 3 groups. According to the findings of the present study, all 3 of the potentially hepatotoxic drugs (isoniazid, rifampicin, and pyrazinamide) can be reintroduced simultaneously at full dosage safely from day 1, especially for patients with bilateral extensive pulmonary tuberculosis, to halt disease transmission or to treat patients with life-threatening tuberculosis.

TRIAL REGISTRATION

ClinicalTrials.gov identifier number: NCT00405301.

Assessment of protective role of polyherbal preparation, Livina, against anti-tubercular drug induced liver dysfunction

The present study evaluated the possible protective role of Livina (a polyherbal preparation) against anti-tubercular therapy (ATT)-induced liver dysfunction in patients of pulmonary tuberculosis. Patients were given intensive phase treatment with 4-drugs (rifampicin, INH, pyrazinamide and ethambutol) used for anti-tubercular therapy for 2 months, followed by a 4-month continuous phase treatment with 2 drugs (rifampicin and INH) under clinical advice and supervision. Both qualitative and quantitative measures of liver function were assessed, at different time intervals, before and after ATT. Analysis of data showed that the incidence of qualitative manifestations of liver dysfunction were greater in the placebo treated group as compared to the test drug group. None of the patients of either group showed clinical jaundice. Most signific changes ant were observed in the SGOT and SGPT levels in the placebo group, wherein the levels of both enzymes were higher at 4 and 8 weeks post-ATT, as compared to the respective baseline (0 week) values. When Livina (2 capsules twice daily) was given with ATT drugs, incidence of qualitative manifestation of liver dysfunction was insignificant and SGOT and SGPT levels were also significantly lower than the placebo+AITT drugs treated group. These results indicate that the test drug (Livina) was efficacious, against ATT-induced hepatic dysfunction in patients of pulmonary tuberculosis.

[EVALUATION OF THE EFFICIENCY OF TREATMENT AND THE CHOICE OF CONTROL COMPUTED TOMOGRAPHY TIME IN CHILDREN WITH MINOR FORMS OF INTRATHORACIC TUBERCULOSIS]

Three chemotherapy regimens (Group 1: 2HRZ/4HR, n = 31; Group 2: 2HRZ/4HZ, n = 33; Group 3: 6HR, n = 33) were comparatively assessed in children with minor forms of intrathoracic tuberculosis diagnosed by the computed tomography (CT). The leading criteria for therapeutic effectiveness were regression of intoxication symptoms and changes in the CT pattern. The results of treatment were equal in all the groups. With the 6HR regimen, varying unavoidable adverse reactions were 4.3-fold less frequently (3.0 ± 3.0% and 12.5 ± 4.1%, respectively; p = 0.25). CT pattern changes by months 2-3 and 6 of therapy were compared. Single control CT investigation by 6 months of therapy was optimal. Additional CT study at 2-3 months of therapy reflected positive changes in most cases, but failed to affect treatment policy.

Serious adverse reactions in a tuberculosis programme setting in Kyrgyzstan

Serious adverse reactions among new smear-positive patients were studied in a programme setting in Kyrgyzstan. Two per cent of patients on tuberculosis (TB) treatment had to interrupt treatment for > or =1 week, and more than 80% of the reactions occurred during the first month of treatment. Pyrazinamide was the most common causative agent, followed by rifampicin.

Epidemiological survey of hyperuricemia as an adverse reaction to antituberculous therapy with pyrazinamide

PURPOSE

Pyrazinamide is an antituberculous drug that is administered as a two-month course during treatment of pulmonary tuberculosis. Adverse reactions to pyrazinamide have been reported to include hyperuricemia. We performed a retrospective multicenter epidemiological survey to assess the relationship between various patient characteristics and the uric acid level, the changes of uric acid during pyrazinamide administration, and the use of medications for uric acid control as well as attacks of gout or arthralgia at the onset of hyperuricemia. A total of 226 patients who were admitted to four hospitals with pulmonary tuberculosis between January and December 2006 and received short-term intensive pyrazinamide therapy were studied.

RESULTS

There were 172 men and 54 women with an average age of 59.5 years and an average body mass index of 19.8 kg/m2. The average serum uric acid concentration before pyrazinamide treatment was 4.73 +/- 1.78 mg/dl, while the average uric acid level after pyrazinamide treatment was 10.63 +/- 2.67 mg/dl, which was significantly higher than the pretreatment level (p<0.0001). During treatment, hyperuricemia (Serum uric acid > or = 8 mg/dl) was reported in 84.5% of patients and arthralgia developed in 4.42%. Although the therapy instituted in 51 patients (22.57%) had to be interrupted or discontinued due to liver dysfunction and skin rashes, which were probably caused by isoniazid and rifampicin, no patient ceased taking pyrazinamide due to an increase of uric acid. Drugs for uric acid control were administered to 21 patients (9.29%). Pyrazinamide is an important agent for intensive short-term antituberculous therapy. Hyperuricemia due to this drug can be managed by observation and does not require interruption of administration.

Clinical evaluation and monitoring of adverse effects for fixed multidose combination against single drug therapy in pulmonary tuberculosis patients

To evaluate the clinical and therapeutic value of 4 and 3 drug fixed dose combinations verses single drug formulations to treat pulmonary tuberculosis patients. The occurrence of adverse effects was also monitored. A total of 293 patients having sputum positive pulmonary tuberculosis were enrolled (Male: 187 and Female: 106). Patients with renal, hepatic, diabetic, cardiac problem and pregnancy were excluded from study. Patients were randomly selected into three groups (A, B, C). Group A and B were given FDCs and group C was given single drug formulations. All patients received 4 drugs in the intensive phase and 3 drugs in the continuation phase. Group A showed the highest percentage of patients who achieved sputum conversion (98.9%). The numbers of days taken to achieve sputum conversion on average were the least for Group B (32 days). When comparing the adverse effects, the patients of Group C suffered the most, with 22 patients who vomited repeatedly, 3 complaining of itching, 2 with Jaundice and 1 dead. There was no significant difference in the efficacy among the three treatment regimens. However the side effects observed in all three groups strongly indicate that FDCs are safer for treating TB patients. There were no side effects in the continuation phase.

Pattern of adverse drug reactions experienced by tuberculosis patients in a tertiary care teaching hospital in Western Nepal

Tuberculosis is a common problem in developing countries including Nepal. Data regarding the safety profile of anti tubercular drugs is lacking in Nepal. The present study analyzed the pattern of ADRs caused by the antitubercular drugs. Inpatient files of all the TB patients who received treatment at the Manipal Teaching Hospital, Pokhara, Nepal during the period from 1st January 2001 till 31st December 2006 were taken. Altogether 326 patients were identified among which 40 (females 24, males 16) experienced at least one ADR (incidence 12.27%). The mean+/-SD age of the patients was 42.12+/-20.41 years. The most common ADR was elevated liver enzymes [24 (57.14%)] and hepatobiliary system was the most common system affected [24 (58.5%)]. More than half the ADRs [21 (52.55%)] developed with in 20 days of initiation of therapy. Isoniazid and pyrazinamide were the suspected drugs responsible for 32.32% each of the total ADRs. The mean+/-SD of the total number of drugs used in the patients were 4.77+/-1.46. The most common laboratory abnormality observed was elevated SGOT level [21 patients (52.5%)]. Seven (17.5%) patients needed specific drug treatment for managing the ADRs and 10 (25%) needed symptomatic management. Thirty five (87.5%) patients recovered following the ADR. Multiple drug therapy was the reason behind the development of 30 (75%) ADRs. It was found that 29 (72.5%) ADRs were 'probably' due to the suspected drugs. Majority [19 (47.5%)] of the ADRs were mild [level (1)]. This study shows that ADRs to anti tubercular drugs are common. Since TB is a common problem in Nepal, special efforts are needed to tackle the drug related complications associated with ATT drugs.

[Case of fatal liver failure due to anti-tuberculous therapy]

A 65-year-old female was started anti-tuberculous therapy for her pulmonary tuberculosis on admission. Liver dysfunction had occurred on 33rd day after starting treatment. AST was elevated to 301 IU/L, and ALT was also elevated to 141 IU/L. Therefore, all medicated drugs were stopped. She had jaundice on 42nd day and liver failure deteriorated. She was medicated with steroids, but she died by liver failure on 64th day. This is a rare case of fatal liver failure due to antituberculous therapy.

Pyrazinamide induced hyperuricaemia presenting as severe bilateral leg cramps

Pyrazinamide is one of the first line drugs used for the treatment of tuberculosis. Hepatotoxicity and hyperuricaemia are important and common untoward effects seen after administration of pyrazinamide. The drug inhibits elimination of urates resulting in hyperuricaemia, the presenting features of which are arthralgia, arthritis or even gout. A-case of bilateral leg cramps due to hyperuricaemia following pyrazinamide therapy is reported here.

Pharmacokinetics and tolerability of a higher rifampin dose versus the standard dose in pulmonary tuberculosis patients

Rifampin is a key drug for tuberculosis (TB) treatment. The available data suggest that the currently applied 10-mg/kg of body weight dose of rifampin may be too low and that increasing the dose may shorten the treatment duration. A double-blind randomized phase II clinical trial was performed to investigate the effect of a higher dose of rifampin in terms of pharmacokinetics and tolerability. Fifty newly diagnosed adult Indonesian TB patients were randomized to receive a standard (450-mg, i.e., 10-mg/kg in Indonesian patients) or higher (600-mg) dose of rifampin in addition to other TB drugs. A full pharmacokinetic curve for rifampin, pyrazinamide, and ethambutol was recorded after 6 weeks of daily TB treatment. Tolerability was assessed during the 6-month treatment period. The geometric means of exposure to rifampin (area under the concentration-time curve from 0 to 24 h [AUC(0-24)]) were increased by 65% (P < 0.001) in the higher-dose group (79.7 mg.h/liter) compared to the standard-dose group (48.5 mg.h/liter). Maximum rifampin concentrations (C(max)) were 15.6 mg/liter versus 10.5 mg/liter (49% increase; P < 0.001). The percentage of patients for whom the rifampin C(max) was > or =8 mg/liter was 96% versus 79% (P = 0.094). The pharmacokinetics of pyrazinamide and ethambutol were similar in both groups. Mild (grade 1 or 2) hepatotoxicity was more common in the higher-dose group (46 versus 20%; P = 0.054), but no patient developed severe hepatotoxicity. Increasing the rifampin dose was associated with a more than dose-proportional increase in the mean AUC(0-24) and C(max) of rifampin without affecting the incidence of serious adverse effects. Follow-up studies are warranted to assess whether high-dose rifampin may enable shortening of TB treatment.

Evaluation of a non-rifampicin continuation phase (6HE) following thrice-weekly intensive phase for the treatment of new sputum positive pulmonary tuberculosis

SETTING

Tuberculosis Research Centre, Chennai and Madurai, South India.

OBJECTIVE

To assess response to treatment, relapse and emergence of MDR TB in newly diagnosed patients with sputum-positive tuberculosis using an intermittent intensive phase followed by a non-rifampicin continuation phase.

DESIGN

Patients were treated in a controlled clinical trial with 2HRZE3/6HE with thrice-weekly direct dosing in the intensive phase and once-weekly with six doses self-administered in the continuation phase. Clinical and bacteriologic evaluation was done every month for 24 months.

RESULTS

The overall outcome was good, with 92% favourable response (cure) and 4.8% relapse in 450 patients including 103 who did not receive extension of intensive phase for positive smear, 38 with initial H-resistant cultures, 4 with MDR TB and 15 who received less than 75% of chemotherapy. In 392 patients with drug-susceptible cultures, 96%were cured and only 4% relapsed. There was no emergence of MDR TB among failures and relapses; toxicity was low.

CONCLUSION

Newly-diagnosed Category I patients can be effectively treated with this regimen without emergence of MDR TB. It has immense potential in programmes where directly observed therapy cannot be ensured throughout, and when rifampicin is contraindicated in HIV-TB patients who require concomitant therapy with anti-retroviral