Incidence, clinical features and impact on anti-tuberculosis treatment of anti-tuberculosis drug induced liver injury (ATLI) in China

Key factors of susceptibility to anti-tuberculosis drug-induced hepatotoxicity

Anti-tuberculosis drug-induced hepatotoxicity (ATDH) is one of the leading adverse drug reactions during the course of tuberculosis treatment and poses a considerable challenge to clinicians and researchers. Previous studies have revealed the important contribution of drug metabolism and transporter enzymes to the complexity of ATDH. The emerging roles of immune response and oxidative stress resulting from reactive metabolite in the development of ATDH have also gained attention recently. Both non-genetic and genetic factors can have a significant impact on the susceptibility to ATDH, consequently altering the risk of hepatotoxicity in susceptible individuals. Non-genetic risk factors associated with ATDH include host factors, environment factors and drug-related factors. Genetic factors contributing to the susceptibility of ATDH involve genetic variations in bioactivation/toxification pathways via the cytochrome P450 enzymes (phase I), detoxification reactions by N-acetyl transferase 2, glutathione S-transferase and uridine diphosphate glucuronosyltransferase (phase II) and hepatic transport (phase III), together with immunological factors and antioxidant response. Better understanding of these factors may help to predict and prevent the occurrence of ATDH and develop more effective treatments. This review focuses on the mechanisms of ATDH and the key factors of susceptibility associated with drug metabolism, hepatic transport, immune response and oxidative stress.

Anti-tuberculosis drugs adverse reactions: a review of the Iranian literature

INTRODUCTION

Tuberculosis (TB) treatment, in particular therapy for multidrug-resistant TB (MDR-TB), is associated with toxicities and adverse drug reactions (ADRs).

AREAS COVERED

This paper reviews Iranian literature reporting ADRs which occurred during tuberculosis treatment. English language papers were sourced from PubMed, ScienceDirect, Wiley, Ovid and Proquest, with Google Scholar searched for Persian language articles. Reported ADRs, proportion of patients with ADRs, risk factors and determinants, as well as the characteristics of the studies were reviewed. 21 articles were included; about 60% of them were in English and three included patients with MDR-TB. The ratio of ADR per capita was 1.9 (in 6 studies) and 33.63% of patients developed an ADR (in 7 studies). Hepatitis (2.5 - 45.3%) was reported in nearly all of the studies. The mean time from initiation of medication to development of hepatitis ranged from 4.67 to 25.25 days (in 6 studies). Most cases of mortality were due to hepatotoxicity. Except for comorbidities and female gender, other risk factors such as HIV and length of hospitalization were only reported in one article.

EXPERT OPINION

The pattern of ADRs in Iranian articles was found to be similar to many other studies in the present review. We suggest that future studies resolve the confounding factors in this area that are mentioned in this review.

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.

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.

Impact of glutathione S-transferase M1 and T1 on anti-tuberculosis drug-induced hepatotoxicity in Chinese pediatric patients

Background

Anti-tuberculosis drug induced hepatotoxicity (ATDH) is a major adverse drug reaction associated for anti-tuberculosis therapy. The glutathione S-transferases (GST) plays a crucial role in the detoxification of hepatotoxic metabolites of anti-tuberculosis drugs.An association between GSTM1/GSTT1 null mutations and increased risk of ATDH has been demonstrated in adults. Given the ethnic differences and developmental changes, our study aims to investigate the potential impacts of GSTM1/GSTT1genotypes on the development of ATDH in Han Chinese children treated with anti-tuberculosis therapy.

Methods

Children receiving anti-tuberculosis therapy with or without evidence of ATDH were considered as the cases or controls, respectively. The GSTM1 and GSTT1 genotyping were performed using the polymerase chain reaction.

Results

One hundred sixty-three children (20 cases and 143 controls) with a mean age of 4.7 years (range: 2 months-14.1 years) were included. For the GSTM1, 14 (70.0%) cases and 96 (67.1%) controls had homozygous null mutations. For the GSTT1, 13 (65.0%) cases and 97 (67.8%) controls had homozygous null mutations. Neither the GSTM1, nor the GSTT1 polymorphism was significantly correlated with the occurrence of ATHD.

Conclusion

Ourresults did not support the GSTM1 and GSTT1 polymorphisms as the predictors of ADTH in Chinese Han children treated with anti-tuberculosis drugs. An age-related association between pharmacogenetics and ATHD need to be confirmed in the further study.

Hepatotoxicity from antituberculous therapy in the elderly: a systematic review

BACKGROUND

Elderly persons have the highest rates of tuberculosis (TB) in the United States compared to all other age groups. A systematic literature review was conducted to determine if older age was a risk factor for hepatotoxicity resulting from treatment with first-line drugs used to treat active (TB) and latent tuberculosis (LTBI).

METHODS

A systematic review of MEDLINE, Cochrane Controlled Trial Registry, CINAHL(®), and Science Citation Index Expanded (from 1970 to 2011) was performed to determine the risk of hepatotoxicity, comparing those over 60 with those under 60. A meta-analysis was performed using a random effects model along with log odds ratios and the chi-square test.

FINDINGS

Thirty-eight studies (40,034 participants; 1208 cases of hepatotoxicity) met the selection criteria. For active TB, an overall mean effect of 0.277 (p = 0.024, 95% CI: 0.037-0.517) was observed, which is equivalent to an odds ratio of 1.32 (95% CI: 1.04-1.68). For LTBI, an overall mean effect of 1.42 (p < 0.001, 95% CI: 0.794-2.05) was observed, which translates to an odds ratio of 4.14 (95% CI: 2.21-7.74).

INTERPRETATION

Our analysis revealed that patients older than 60 had significantly more risk of hepatotoxicity. These studies suggest that a gentler regimen of treatment for older individuals could benefit health outcomes in this population of TB patients and minimize risks to the public's health.

Adverse reactions to antituberculosis drugs in Iranian tuberculosis patients

Background. Antituberculosis multidrug regimens have been associated with increased incidence of adverse drug reactions (ADRs). This study aimed to determine the incidence and associated factors of ADRs due to antituberculosis therapy. Methods. This is a retrospective cross-sectional study on tuberculosis patients who were treated in tuberculosis clinics in Markazi province in Iran. The information contained in the medical files was extracted and entered into the questionnaire. Data was descriptively analyzed by using statistical package for social sciences (SPSS 18). Results. A total of 940 TB patients of 1240 patients' medical records available in 10 medical offices were included in this study. Of the 563 ADRs found in this study, 82.4% were considered minor reactions and 17.6% were major reactions. No death from antituberculosis ADR was observed. We found that the risk of major ADRs was higher in females (P  value = 0.0241), age >50 y (P  value = 0.0223), coinfection with HIV (P  value = 0.0323), smoking (P  value = 0.002), retreatment TB (P  value = 0.0203), and comorbidities (P  value = 0.0005). Conclusions. This study showed that severe side effects of anti-TB drugs are common in patients who have risk factors of ADRs and they should be followed up by close monitoring.

The association between HLA-DQB1 polymorphism and antituberculosis drug-induced liver injury: a Case-Control Study

WHAT IS KNOWN AND OBJECTIVE

Research on genetic factors associated with antitubercular drug-induced liver injuries (ATLI) has been reported. However, most of the research has focused on genetic polymorphisms of genes encoding metabolic enzymes, including NAT2, GST and CYP450. It is probable that the immune system also contributes to the onset of drug adverse effects. A few small studies have explored the possible association of HLA genes with drug-induced liver injuries (DILI), but more supportive evidence from larger studies or prospective cohort designs is needed. We aim to explore the possible association of HLA-DQB1 gene polymorphisms with ATLI in a case-control study.

METHODS

A case-control study design was used. ATLI was recorded in a prospectively followed-up cohort of patients receiving antituberculosis treatment. Identified cases were matched with control tuberculosis patients within the same cohort but with no adverse effects in 1 : 1 ratio. We used the sequence-based typing method to determine the HLA-DQB1 genotypes. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression.

RESULTS AND DISCUSSION

Eighty-nine cases were included in this case-control study. HLA-DQB1 typing was successful for 177 subjects. No association between frequency of HLA-DQB1 genotypes and ATLI was statistically significant in univariate analyses. Multivariate analysis using the conditional logistic regression model revealed that the individuals with two DQB1*05 alleles were at higher risk of ATLI than control subjects. The OR was 5.28 adjusted for use of liver protective drugs and weight (10/88 VS 2/88, 95% CI: 1.134-24.615, P = 0.034). Analysis according to the liver injury type showed that both mixed liver injury patients and cholestatic/mixed liver injury patients had higher proportions of DQB1*05 : 02 alleles (P values were 0.028 and 0.005, respectively).

WHAT IS NEW AND CONCLUSION

This study suggests that ATLI was more likely in subjects of HLA-DQB1*05/*05 genotype. Further studies are needed to verify this association.

Treatment response and adverse reactions in older tuberculosis patients with immunocompromising comorbidities

PURPOSE

The aim of this study was to elucidate the effects of immunocompromising comorbidities on treatment response and adverse reactions in older tuberculosis (TB) patients.

MATERIALS AND METHODS

The medical records of 182 patients older than 65 years with proven TB by positive culture of Mycobacterium tuberculosis and with available drug susceptibility tests were reviewed retrospectively. These patients were subsequently assigned to either the comorbidity group (n=78) or non-comorbidity group (n=104) depending on whether they had immunocompromising comorbidities.

RESULTS

The mean durations of treatment were 9.9 ± 3.3 months in the comorbidity group and 9.3 ± 3.2 months in the non-comorbidity group (p=0.21). M. tuberculosis culture results converted to negative in most patients with available follow-up cultures at two months after treatment. The successful treatment rates were 94.9% and 98.9% in the comorbidity and non-comorbidity groups, respectively (p=0.30). The most common side effects of anti-TB treatment were skin rash/pruritus (13% in the comorbidity group vs. 11% in the non-comorbidity group, p=0.79), gastro-intestinal problems (14% vs. 9%, p=0.25) and hepatotoxicity (14% vs. 7%, p=0.09).

CONCLUSION

The present study shows that the successful treatment rate for TB is high and that immunocompromising comorbidities have no effect on the response to treatment and adverse effects in older TB patients.

Cost utility of lateral-flow urine lipoarabinomannan for tuberculosis diagnosis in HIV-infected African adults

SETTING

In-patient hospitals in South Africa and Uganda.

OBJECTIVE

To evaluate the cost-effectiveness of a lateral-flow urine lipoarabinomannan (LAM) test when added to existing strategies for tuberculosis (TB) diagnosis in human immunodeficiency virus infected adults (CD4(+) T-cell counts < 100 cells/l) with symptoms of active TB.

DESIGN

Decision-analytic cost-utility model, with the primary outcome being the incremental cost-effectiveness ratio, expressed in 2010 US dollars per disability-adjusted life year (DALY) averted from the perspective of a public sector TB control program.

RESULTS AND CONCLUSION

For every 1000 patients tested, adding lateral-flow urine LAM generated 80 incremental appropriate anti-tuberculosis treatments and averted 224 DALYs. Estimated cost utility was US$353 per DALY averted (95% uncertainty range $192$1161) in South Africa and $86 per DALY averted (95% uncertainty range $49$239) in Uganda, reflecting the lower treatment costs in Uganda. Cost utility was most sensitive to assay specificity, cost of anti-tuberculosis treatment, life expectancy after TB cure and cohort TB prevalence, but did not rise above $1500 per DALY averted in South Africa under any one-way sensitivity analysis. The probability of acceptability was >99.8% at a per-DALY willingness-to-pay threshold equal to the per capita gross domestic product in South Africa ($7275) and Uganda ($509).

Adverse reactions due to directly observed treatment strategy therapy in Chinese tuberculosis patients: a prospective study

Background

More than 1 million tuberculosis (TB) patients are receiving directly observed treatment strategy (DOTS) therapy in China every year. As to the profile of adverse drug reactions (ADRs) due to DOTS therapy, no consensus has been reached. There is no report regarding ADRs due to DOTS therapy with a large Chinese TB population. This study aimed to determine the incidence and prognosis of ADRs due to DOTS therapy, and to evaluate their impact on anti-TB treatment in China.

Methods

A prospective population-based cohort study was performed during 2007–2008. Sputum smear positive pulmonary TB patients who received DOTS therapy were included and followed up for six to nine months in 52 counties of four regions in China. The suspected ADRs were recorded and reviewed by Chinese State Food and Drug Administration.

Results

A total of 4304 TB patients were included in this study. 649 patients (15.08%) showed at least one ADR and 766 cases in total were detected. The incidence (count) of ADR based on affected organ was: liver dysfunction 6.34% (273), gastrointestinal disorders 3.74% (161), arthralgia 2.51% (108), allergic reactions 2.35% (101), neurological system disorders 2.04% (88), renal impairment 0.07% (3) and others 0.05% (2). Most cases of ADRs (95%) had a good clinical outcome, while two with hepatotoxicity and one with renal impairment died. Compared with patients without ADRs, patients with ADRs were more likely to have positive smear test results at the end of the intensive phase (adjusted OR, 2.00; 95%CI, 1.44–2.78) and unsuccessful anti-TB outcomes (adjusted OR, 2.58; 95%CI, 1.43–4.68).

Conclusions

The incidence of ADRs due to DOTS therapy was 15.08%. Those ADRs had a substantial impact on TB control in China. This highlighted the importance of developing strategies to ameliorate ADRs both to improve the quality of patient care and to control TB safely.

Anti-tuberculosis drug induced hepatotoxicity among TB/HIV co-infected patients at Jimma University Hospital, Ethiopia: nested case-control study

BACKGROUND

This study was carried out to determine the incidence and predictors of anti-tuberculosis drug induced hepatotoxicity among TB/HIV co-infected patients at Jimma University Hospital, Ethiopia.

METHODS/PRINCIPAL FINDINGS

A nested case-control study was conducted by reviewing charts of all TB/HIV co-infected patients who commenced anti-TB treatment from January 2008 to December 2011 at Jimma University Hospital. Patients who had developed hepatotoxicity after at least 5 days of standard doses of anti-TB drug therapy were labeled as "cases" and those without hepatotoxicity were "controls". Each case with anti-TB drug induced hepatotoxicity was compared with 3 controls selected randomly from the cohort. From a cohort of 296 TB/HIV co-infected patients 8 were excluded from the study as the causality between anti-TB drugs and hepatotoxicity was not confirmed, 33 had developed hepatotoxicity. On bivariate logistic regression analysis, body mass index (BMI) <18.5 Kg/m(2) [P = 0.01; OR (95%CI): 3.6 (1.4-9.5)], disseminated pulmonary TB [P = 0.00; OR (95%CI): 5.6 (2.2-14.6)], CD4 count ≤50 [P = 0.016; OR (95%CI): 3.6(1.27-10.23)] and WHO stage 4 [P = 0.004, OR (95%CI): 3.8 (1.68-8.77)] were significantly associated with anti-TB drug induced hepatotoxicity. Predictor variables with p-value <0.05 by bivariate analysis were analyzed using multivariable logistic regression analysis and identified disseminated pulmonary TB [P = 0.001; AOR (95%CI) = 5.6 (2.1-15.0)] and BMI <18.5 [P = 0.014; AOR (95%CI)= 3.6 (1.3-10.1)] as independent predictors of anti-TB drug induced hepatotoxicity.

CONCLUSIONS

The incidence of anti-TB drug induced hepatotoxicity was 11.5%. The results suggest that in the presence of disseminated pulmonary TB and/or BMI <18.5 Kg/m(2), TB/HIV co-infected patients should be closely followed for the occurrence of hepatotoxicity during the intensive phase of TB treatment to prevent morbidity and mortality.

Frequency of latent and smear positive tuberculosis in chronic psychotic disorders

OBJECTIVE

Screening is one of the ways to combat Tuberculosis (TB) and should be mostly concentrated on groups showing some symptoms of the disease. Tuberculosis can be transferred from person to person in laboratories, prisons and psychiatry hospitals. The purpose of this study was to survey pulmonary TB in patients with schizophrenia in Rasht.

METHODS

In this descriptive-cross sectional, Two hundred fifty seven consecutive patients with chronic psychotic disorder hospitalized in psychotic hospitals underwent purified protein derivative (PPD) test. PPD test was done with the unit 5T which was injected subcutaneously on anterior surface and at the top of left forearm. The results of the test were interpreted by the pen technique method and based on transverse diameter of induration of about 48-72 hrs. Induration size due to hypersensitivity to PPD more than 10mm was considered positive. Patients with positive PPD test underwent complementary sputum smear. Data were analyzed using chi- square and T test.

RESULTS

The mean age of patients was 45±10 years; 75.5% were male, 74.7% were single, 10.5% married, 7.8% divorced, and 68.1% were smokers. These patients suffered from chronic psychotic disorder at the mean time of 15±7.9 years. In 74 patients (28%) positive PPD test were recorded, but active pulmonary TB was not found in complementary experiments of PPD sample. Based on data analysis, only age and gender showed a significant relationship with the results of the PPD test (P < 0.05).

CONCLUSIONS

This study showed that patients with positive PPD test are much more than the normal population, but active pulmonary TB was not observed in our samples. Since these patients are in clinical and closed places, more programs for screening are required.

Outcome and determinants of mortality in 269 patients with combination anti-tuberculosis drug-induced liver injury

BACKGROUND AND AIM

Worldwide anti-tuberculosis (TB) drug-induced liver disease (DILI) is an important cause of hepatotoxicity, and drug-induced acute liver failure (ALF). Reported series on anti-TB DILI are limited by a mix of cases with mild transaminase elevation or adaptation. Our aim was to analyze the clinical features, laboratory characteristics, outcome, and determine predictors of 90-day mortality.

METHODS

Single center analysis of consecutive cases of anti-TB DILI following combination anti-TB drugs exposure from 1997-2011.

RESULTS

Of the 269 patients, 191 (71%) experienced jaundice and 69 (25.7%) accounted for ALF. The mean age and treatment duration was 41.3 years and 1.9 months, respectively; males constituted 55.7%. DILI occurred throughout the course of treatment; three-quarters occurred within the first 2 months. HIV infection was present in 21 (7.8%). The 90-day mortality was 22.7%. DILI accompanied by jaundice (n = 191), encephalopathy (n = 69) or ascites (n = 69) resulted in mortality in 30%, 69.6% and 50.7%, respectively (P < 0.001). Age, gender, transaminase levels, HIV or hepatitis B surface antigen (HBsAg) status did not influence survival. Treatment duration, encephalopathy, ascites, bilirubin, serum albumin, international normalized ratio (INR), serum creatinine and leukocyte count were associated with mortality (P < 0.001). Multivariate logistic regression model for mortality, incorporating encephalopathy, albumin, bilirubin, INR, and creatinine yielded a C-statistic of 97%.

CONCLUSIONS

Anti-TB DILI occurs throughout treatment duration progressing to ALF in a quarter of patients. The overall mortality is 22.7%, which is higher when accompanied by jaundice, ascites or encephalopathy. An anti-TB DILI model, incorporating bilirubin, INR, encephalopathy, serum creatinine and albumin predicted mortality with C-statistic of 97%.

Genetic interaction between NAT2, GSTM1, GSTT1, CYP2E1, and environmental factors is associated with adverse reactions to anti-tuberculosis drugs

BACKGROUND

Adverse drug reactions (ADRs) associated with anti-tuberculosis (anti-TB) drug regimens have considerable impact on anti-TB treatment, potentially leading to unsuccessful outcomes. Nevertheless, the risk factors that play a role in anti-TB drug-induced ADRs are not well established. It is well documented that genetic polymorphisms in drug-metabolizing enzymes (DMEs) result in considerably complex variability in anti-TB drug disposition. In addition, the impact of pharmacogenetic variation on the metabolism of anti-TB drugs may be modifiable by environmental exposure. Thus, an assessment of pharmacogenetic variability combined with biomarkers of environmental exposure may be helpful for demonstrating the effect of the gene-environment interaction on susceptibility to ADRs induced by anti-TB drug therapy.

OBJECTIVE

The aim of the study was to investigate the impact of the interaction between environmental risk factors and pharmacogenetic polymorphisms in four common DMEs--N-acetyltransferase 2 (arylamine N-acetyltransferase) [NAT2], glutathione S-transferase theta 1 [GSTT1], glutathione S-transferase mu 1 [GSTM1], and cytochrome P450 2E1 [CYP2E1]--on commonly reported ADRs to first-line anti-TB drugs in 129 patients receiving homogeneous TB treatment.

METHODS

TB patients monitored during drug treatment were divided into subgroups according to the presence or absence of ADRs. Additionally, the patients' clinical and demographic characteristics were collected in order to identify the environmental factors that are potential triggers for ADRs induced by anti-TB drug treatment. Pharmacogenetic variability was determined by gene sequencing, TaqMan® assays, or polymerase chain reaction.

RESULTS

The findings of this study suggest that the NAT2 slow acetylator haplotype, female sex, and smoking are important determinants of susceptibility to ADRs induced by anti-TB drugs. Patients carrying multiple, but not single, polymorphisms in the NAT2, GSTM1, GSTT1, and CYP2E1 genes were found to have an increased risk of ADRs, as revealed by gene-gene interaction analysis. Moreover, we also identified meaningful gene-environment interaction models that resulted in the highest levels of ADR risk.

CONCLUSION

The study findings provide evidence of the clinical impact of the interaction between pharmacogenetic variability and environmental factors on ADRs induced by anti-TB drug therapy. Predictive pharmacogenetic testing and a comprehensive clinical history would therefore be helpful for identification and careful monitoring of patients at high risk of this complication.

Tuberculosis in an urban area in China: differences between urban migrants and local residents

Background

The increase in urban migrants is one of major challenges for tuberculosis control in China. The different characteristics of tuberculosis cases between urban migrants and local residents in China have not been investigated before.

Methodology/Principal Findings

We performed a retrospective study of all pulmonary tuberculosis patients reported in Songjiang district, Shanghai, to determine the demographic, clinical and microbiological characteristics of tuberculosis cases between urban migrants and local residents. We calculated the odds ratios (OR) and performed multivariate logistic regression to identify the characteristics that were independently associated with tuberculosis among urban migrants. A total of 1,348 pulmonary tuberculosis cases were reported during 2006–2008, among whom 440 (32.6%) were local residents and 908 (67.4%) were urban migrants. Urban migrant (38.9/100,000 population) had higher tuberculosis rates than local residents (27.8/100,000 population), and the rates among persons younger than age 35 years were 3 times higher among urban migrants than among local residents. Younger age (adjusted OR per additional year at risk = 0.92, 95% CI: 0.91–0.94, p<0.001), poor treatment outcome (adjusted OR = 4.12, 95% CI: 2.65–5.72, p<0.001), and lower frequency of any comorbidity at diagnosis (adjusted OR = 0.20, 95% CI: 0.13–0.26, p = 0.013) were significantly associated with tuberculosis patients among urban migrants. There were poor treatment outcomes among urban migrants, mainly from transfers to another jurisdiction (19.3% of all tuberculosis patients among urban migrants).

Conclusions/Significance

A considerable proportion of tuberculosis cases in Songjiang district, China, during 2006–2008 occurred among urban migrants. Our findings highlight the need to develop and implement specific tuberculosis control strategies for urban migrants, such as more exhaustive case finding, improved case management and follow-up, and use of directly observed therapy (DOT).

Effect of scheduled monitoring of liver function during anti-Tuberculosis treatment in a retrospective cohort in China

Background

Data on effect of regular liver function monitoring during anti-TB treatment is limited in China. This study aimed to evaluate the effects of scheduled liver function monitoring on identification of asymptomatic liver damage and anti-TB treatment outcomes during anti-TB treatment.

Methods

A retrospective analysis was performed based on a national-level cohort study. A total of 273 patients developing liver dysfunction were divided into two groups, 111 patients who were diagnosed through scheduled liver function test within two months after initiation of anti-TB treatment formed scheduled monitoring group, others who were diagnosed due to developing symptoms formed passive detection group (n = 162). The two groups were compared through clinical features, prognosis of liver dysfunction and impact on anti-TB treatment using propensity score weighting analysis.

Results

33.3% of 273 patients did not have any clinical symptoms, including 8 with severe hepatotoxicity. 1.8% in scheduled monitoring group and 11.1% in passive detection group required hospitalization (P = 0.004). Regarding the prognosis of liver dysfunction, most patients recovered, no death happened in scheduled monitoring group while 3 died in passive detection group. In terms of impact on anti-TB treatment, 35.1% in scheduled monitoring group and 56.8% in passive detection group changed their anti-TB treatment (P = 0.001).

Conclusions

Scheduled monitoring is effective in identifying asymptomatic liver damage, reducing hospitalization rate and improving compliance of anti-TB treatment.

CYP2E1, GSTM1 and GSTT1 genetic polymorphisms and susceptibility to antituberculosis drug-induced hepatotoxicity: a nested case-control study

WHAT IS KNOWN AND OBJECTIVE

The pathogenic mechanism of antituberculosis drug-induced hepatotoxicity (ATDH) is thought to involve drug-metabolizing enzymes including N-acetyl transferase2 (NAT2), cytochrome P4502E1 (CYP2E1) and glutathione S-transferase (GST) M1, T1. The associations between genetic polymorphisms of those genes and ATDH have been reported but with inconsistent results. Moreover, most studies were hospital-based retrospective studies and not prospective. We aimed to investigate possible associations of CYP2E1, GSTM1 and GSTT1 genetic polymorphisms with ATDH using a more robust case-control study nested in a population-based prospective antituberculosis treatment cohort.

METHODS

A total of 4304 patients with smear-positive tuberculosis (TB) who received standard short-course chemotherapy were monitored for 6-9 months. Incidence density sampling method was adopted to select controls and 4 : 1 matched with each ATDH cases by age (± 5 years), sex, treatment history, disease severity and drug dosage. The CYP2E1, GSTM1 and GSTT1 polymorphisms were genotyped using PCR-RFLP and multiplex PCR methods. Conditional logistic regression model was used to calculate odds ratio (OR) and 95% confidence interval (CI), as well as corresponding P-values.

RESULTS AND DISCUSSION

A total of 89 ATDH cases and 356 controls were included in this study. There was no statistically significant association between CYP2E1 RsaI c1/c1 genotype or DraI C/C genotype and ATDH (OR = 0·99, 95% CI:0·62-1·59; OR = 1·13, 95% CI: 0·40-3·20, respectively) compared with CYP2E1 RsaI c1/c2 or c2/c2 genotypes or DraI D/D genotype, or between GSTM1/GSTT1 null genotypes and ATDH (OR = 1·22, 95% CI: 0·76-1·96; OR = 0·96, 95% CI: 0·60-1·52, respectively) compared with non-null genotypes.

WHAT IS NEW AND CONCLUSION

This is the first study of the involvement of CYP2E1, GSTM1 and GSTT1 genetic polymorphisms in ATDH using a nested case-control population-based prospective cohort design. We could not confirm positive associations of genetic polymorphisms of CYP2E1 RsaI, CYP2E1 DraI, GSTM1 null and GSTT1 null with ATDH reported by various groups, in our Chinese TB population.