Risk factors of hepatitis during anti-tuberculous treatment and implications of hepatitis virus load

NAT2 Acetylation Status Predicts Hepatotoxicity During Antituberculosis Therapy: Cumulative Risk Analysis of a Multiethnic Cohort

Antituberculosis drug-induced hepatotoxicity (ATDH) is a common adverse drug reaction often requiring treatment interruption, complicating tuberculosis management. The slow acetylator phenotype, characterized by reduced N-acetyltransferase 2 (NAT2) enzyme activity, is associated with increased hepatotoxicity risk, while rapid acetylators are associated with a higher risk of therapeutic failure. This study investigates the association between the NAT2 acetylation phenotype and ATDH occurrence, with an emphasis on its predictive value in regard to a multiethnic population and its impact on the timing of ATDH onset. A retrospective observational study was conducted on tuberculosis patients treated at Luigi Sacco Hospital, Milan, Italy (July 2020-September 2023). The NAT2 genotyping identified slow and rapid/intermediate acetylators. Cumulative incidence analysis and Fine-Gray competing risks regression models were used to assess ATDH risk and onset timing. Among 102 patients, 21.6% developed ATDH, including 16.7% with slow and 4.9% with rapid/intermediate acetylators. ATDH onset was significantly earlier in regard to slow acetylators (median 0.5 vs. 2 months, interquartile range-IQR: 0.5-3 vs. 1.7-5.5). Slow acetylators were associated with a higher risk of developing ATDH (Sub-distribution hazard ratio, SHR = 3.05; 95% confidence interval-CI: 1.17-7.95; p = 0.02), even after adjusting for confounders. The NAT2 acetylation phenotype strongly influences ATDH risk and timing. Early acetylator status identification may enable dose adjustments, enhancing treatment safety. These findings highlight the role of pharmacogenetics in optimizing antituberculosis therapy by improving efficacy and minimizing toxicity.

NAT2 Slow Acetylator Phenotype as a Significant Risk Factor for Hepatotoxicity Caused by Antituberculosis Drugs: Results From a Multiethnic Nested Case-Control Study

BACKGROUND

Under standard therapies, the incidence of drug-induced liver injury (DILI) in patients with tuberculosis ranges from 2% to 28%. Numerous studies have identified the risk factors for antituberculosis DILI; however, none have been conducted in a multiethnic real-world setting. The primary outcome of the current study was to identify the risk factors that could be used as the best predictors of DILI in a multiethnic cohort.

METHODS

A nested case-control study was conducted in patients at the tuberculosis clinic of Luigi Sacco Hospital in Milan.

RESULTS

The study included 102 patients (mean age [SD], 45.6 [15.6] years). For each patient with hepatotoxicity, 2 controls were matched for sex, age, body mass index, tuberculosis/tuberculosis infection diagnosis, and index date. We found that N-acetyltransferase 2 gene (NAT2) slow acetylator status was the best independent predictor of DILI (odds ratio, 5.97 [95% confidence interval, 1.38-25.76]; P = .02].

CONCLUSIONS

NAT2 genotype-guided dosing may help optimize antituberculosis drug treatment and prevent treatment failure.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov NCT06539455.

The prevalence, clinical reasoning and impact of non-standard anti-tuberculosis regimens at the initial prescription

Regarding clinically-concerning non-standard initial anti-tuberculous (TB) regimens, few studies have examined their prevalence, risk factors and impacts. We recruited patients with drug susceptible TB and non-standard initial anti-TB regimens (NSTB group) and matched them with patients with standard initial regimens (STB group) in a 1:1 ratio. The risk factors and outcomes were analyzed. During the 11-year study period, we analyzed 50 (3.7%) patients with NSTB from a total set of 1337 patients with drug-susceptible TB. Pyrazinamide (60%) was the drug most commonly not prescribed in the NSTB group, followed by ethambutol (34%). Multivariable logistic regression identified independent risk factors as underlying eye disease (adjusted odds ratio [aOR]: 8.869; 95% CI 2.542-30.949; p = 0.001), gout/hyperuricemia (aOR: 4.012 [1.196-13.425]; p = 0.024), and liver disease (aOR: 12.790 [3.981-41.089]; p < 0.001). The NSTB group had longer treatment durations (281 ± 121 vs. 223 ± 63 days; p = 0.003) and more occurrences of treatment interruption (26% vs. 8%; p = 0.021) than the STB group. In conclusion, NSTB occurs in around 3.7% of patients and is associated with longer treatment and more treatment interruption. The risk factors might include underlying liver and eye diseases, and gout. Further studies to improve non-standard initial regimens and prevent negative outcomes are warranted.

Prevalence of Hepatitis B Virus, Human Immune Deficiency Virus and Associated Risk Factors Among Individuals with Presumptive Pulmonary Tuberculosis Attending at Saint Peter's Specialized Hospital, Addis Ababa, Ethiopia

Background

Hepatitis B virus (HBV), human immunodeficiency virus (HIV) and tuberculosis are the causes of widely spread infectious disease, especially in resource-limited countries. The extent of HBV infection and its contributing factors among people with suspected pulmonary tuberculosis (PTB) were not adequately addressed.

Objective

To assess the prevalence of HBV, HIV & their associated risk factors and the magnitude of TB among individuals with presumptive pulmonary tuberculosis attending at St. Peter's Specialized Hospital, Addis Ababa, Ethiopia.

Methods

A cross-sectional study was conducted among 387 individuals with presumptive PTB from October to December 2020. A standard questionnaire was used to collect socio-demographic data and associated risk factors. Sputum samples were analyzed by GeneXpert, Florescent Microscopy and Ziehl-Nelson staining technique. HBsAg test was carried out using Murex Version 3 ELISA test kit from serum/Plasma samples, HIV testing was performed by rapid HIV test kits and data were analyzed using SPSS version 23.

Results

The mean age of study participants was 44.2 years. Overall, 14 (3.6%), 28 (7.2%) and 37 (9.6%) of them were positive for HBV, HIV & TB, respectively. Only single patient was HBV-HIV co-infected (0.3%). The TB-HIV co-infection was identified in 6 (1.6%). In multivariate analysis, being partner separated, alcohol consumption, body piercing and having multiple sexual partners were significantly associated with HBV infection. Having a spouse, who is divorced, widowed, sharing scissors, alcohol consumption and contact with multiple sexual partners also significantly associated with HIV infection.

Conclusion

This study showed that HBV, HIV and TB are still public health issues that need awareness and health education on the risky behaviors and transmission of HBV, HIV & TB among individuals with presumptive TB suspects. Further large-scale study is necessary.

Rate of occult hepatitis B virus infection among individuals with tuberculosis in northeastern Iran: A molecular epidemiological study

One third of the world population has a history of exposure to the hepatitis B virus (HBV), and two billion people are infected with latent tuberculosis (TB). Occult hepatitis B infection (OBI) is defined as the presence of replicative-competent HBV DNA in the liver with detectable or undetectable HBV DNA in the serum of individuals testing negative for the HBV surface antigen (HBsAg). Screening with HBV DNA could identify OBI and significantly reduce carriers and complications of chronic hepatitis B (CHB). This study aims to assess HBV serological markers and OBI molecular diagnosis among people with TB in Mashhad, northeastern Iran. We have performed HBV serological markers (HBsAg, HBc antibodies (Ab) and HBs Ab) in 175 participants. Fourteen HBsAg+ sera were excluded for further analysis. The presence of HBV DNA (C, S, and X gene regions) was assessed by the qualitative real-time PCR (qPCR) method. Frequencies of HBsAg, HBc, and HBs Ab were 8% (14/175), 36.6% (64/175), and 49.1% (86/175), respectively. Among these 42.9% (69/161) were negative for all HBV serological markers. The S, C, and X gene regions were positive in 10.3% (16/156), 15.4% (24/156), and 22.4% (35/156) of participants, respectively. The total OBI frequency was estimated at 33.3% (52/156) when based on detecting one HBV genomic region. Twenty-two and 30 participants had a seronegative and seropositive OBI, respectively. Thorough screening of high-risk groups with reliable and sensitive molecular methods could lead to OBI identification and decrease CHB long-term complications. Mass immunization remains critical in preventing, reducing, and potentially eliminating HBV complications.

Hepatotoxicity and tuberculosis treatment outcomes in chronic liver disease

Background:

The treatment of tuberculosis (TB) is known to cause liver injury, however, there is limited data to guide optimal treatment for patients with chronic liver disease.

Methods:

We undertook a retrospective case series of patients with chronic liver disease and TB disease. The primary objective was to determine if there was a difference in the incidence of drug-induced liver injury (DILI) in patients with cirrhosis versus those with chronic hepatitis. Additionally, we sought to compare TB treatment outcomes, type and duration of therapy, and incidence of adverse events.

Results:

We included 56 patients (chronic hepatitis 40; cirrhosis 16). There were 33 patients (58.9%) who experienced DILI requiring treatment modification, with no significant difference between groups: 65% vs. 43.8%, p = 0.23. Patients with chronic hepatitis were more likely to receive treatment with standard first-line intensive phase therapy that included a combination of rifampin (RIF), isoniazid, and pyrazinamide (80.8% vs. 19.2%, p = 0.03) and any regimen than included isoniazid (92.5% vs. 68.8%, p = 0.04). The risk of DILI was higher when more hepatotoxic TB medications were used. Overall treatment success in this cohort was low (55.4%), with no significant difference between groups (62.5% vs. 37.5%, p = 0.14). Most patients with treatment success (97%) were able to tolerate a rifamycin.

Conclusions:

The risk of DILI is high, especially with the use of isoniazid, in patients with TB and chronic liver disease. This risk can be effectively mitigated with no difference in treatment outcomes in the presence of cirrhosis.

Risk of drug-induced liver injury in chronic hepatitis B and tuberculosis co-infection: A systematic review and meta-analysis

Patients with tuberculosis (TB) disease treated with multi-drug regimens are at risk of developing drug induced liver injury (DILI), and DILI risk might be even higher in patients with underlying liver disease. We aimed to evaluate whether underlying chronic hepatitis B virus (HBV) and TB co-infection are associated with a higher risk of TB therapy-related DILI. We conducted a systematic review and meta-analysis using MEDLINE/PubMed from inception to 31 December 2021. Primary outcome assessed was development of DILI following multi-drug TB treatment. Meta-analysis using random-effects models were utilized to evaluate whether underlying chronic HBV was associated with increased risk of DILI in patients undergoing active TB treatment. A total of 10 studies met inclusion criteria to be analysed, among which 520 patients had HBV-TB co-infection and 2988 patients had active TB disease without HBV. Prevalence of DILI was 21.9% in HBV-TB co-infected patients and 11.9% in TB patients without HBV. On meta-analysis, HBV-TB co-infected patients had significantly higher risk of DILI when treated with TB therapies compared with TB patients without HBV (pooled risk ratio 1.98, 95% CI 1.38-2.83, I²  = 68%). Sub-analysis of prospective cohort studies conducted after year 2000 detected a pooled risk ratio of 2.75 (95% CI 2.10-3.59, I²  = 0%). In conclusion, HBV-TB co-infected patients undergoing multi-drug TB therapy have 2-3 times higher risk of DILI compared with TB patients without HBV. Routine HBV screening prior to initiation of TB therapy is critical for early identification of HBV-TB co-infection, so that clinicians can modify TB and HBV treatment and management to reduce risks of DILI.

Prevalence of Hepatitis B Virus and Latent Tuberculosis Coinfection in the United States

CONTEXT

Underlying chronic hepatitis B virus (HBV) infection increases the risk of drug-induced liver injury (DILI) when receiving tuberculosis therapies. Prevalence of HBV and latent tuberculosis infection (LTBI) coinfection is not well reported and no studies have evaluated testing patterns for and prevalence of HBV-LTBI coinfection in the United States.

OBJECTIVE

To evaluate patterns of HBV and LTBI testing and prevalence of HBV-LTBI coinfection in the United States.

DESIGN

Retrospective cohort study.

SETTING

Quest Diagnostics clinical laboratory data, 2014-2020.

PATIENTS

Chronic HBV infection was defined as any combination of 2 positive HBV surface antigen, HBV e antigen, or detectable HBV DNA tests at least 6 months apart. LTBI was defined as a positive QuantiFERON-TB or T-SPOT.TB test without evidence of active tuberculosis infection.

MAIN OUTCOME MEASUREMENTS

Testing patterns for chronic HBV infection and LTBI and prevalence of HBV-LTBI coinfection were evaluated from 2016 through 2020 and stratified by age, sex, and race and ethnicity.

RESULTS

Among 89 259 patients with chronic HBV infection, 9508 (10.7%) were tested for LTBI, among whom prevalence of HBV-LTBI coinfection was 19.6%, more than twice the observed prevalence of LTBI in patients with no chronic HBV infection in our cohort. Among 394 817 LTBI patients, 127 414 (32.3%) were tested for HBV, among whom prevalence of HBV-LTBI coinfection was 1.5%, approximately 3 times higher than prevalence of HBV infection in patients with no LTBI. The HBV-LTBI coinfection prevalence was highest among Asian Americans and older individuals.

LIMITATIONS

The HBV-LTBI coinfection prevalence was likely underestimated because of suboptimal awareness and testing among at-risk populations.

CONCLUSION

Among US individuals with chronic HBV infection or LTBI, prevalence of HBV-LTBI coinfection is substantial and highlights the need of testing for HBV-LTBI coinfection to mitigate risk of DILI associated with tuberculosis medications in patients with chronic HBV infection.

Estimating Prevalence of Hepatitis B Virus Coinfection Among Adults With Tuberculosis: A Systematic Review With Meta-analysis

BACKGROUND

While patients with hepatitis B virus (HBV) infection and tuberculosis (TB) have similar risk factors, little is known regarding the prevalence of HBV and TB coinfection. We aim to evaluate the prevalence of HBV among patients with TB across world regions.

METHODS

We systematically reviewed the literature using PubMed from inception through September 1, 2019, to identify studies that provided data to calculate HBV coinfection prevalence among adults with TB infection. Prevalence estimates of HBV coinfection among TB patients were stratified by world regions and calculated using meta-analyses with random-effects models.

RESULTS

A total of 36 studies met inclusion criteria (4 from the Africa region, 6 from the Americas region, 5 from the Eastern Mediterranean region, 2 from European region, 6 from Southeast Asia region, and 13 from the Western Pacific region). On meta-analysis, overall pooled HBV coinfection prevalence among TB patients was 7.1%, but varied by world region. Region-specific pooled HBV prevalence among TB patients was highest in Africa region [11.4%, 95% confidence interval (CI): 3.45-19.31] and Western Pacific region (10.8%, 95% CI: 8.68-12.84), and was lowest in the Americas (2.2%, 95% CI: 0.78-3.53). Sensitivity analyses yielded similar HBV prevalence estimates across world regions.

CONCLUSIONS

In this meta-analysis, we observed HBV coinfection prevalence among TB patients to be 38% to 450% higher than published estimates from the Polaris group of region-specific overall HBV prevalence. Timely identification of HBV infection among TB patients will improve patient outcomes by allowing for closer clinical monitoring and management, which may reduce the risk of liver dysfunction and liver failure related to TB treatment.

NAT2 and CYP2E1 polymorphisms and antituberculosis drug-induced hepatotoxicity in Peruvian patients

BACKGROUND

In Peru, 32,970 people were diagnosed with tuberculosis (TB) in 2019. Although TB treatment is effective, 3.4%-13% is associated with significant adverse drug reactions (ADR), considering drug-induced liver injury (DILI) as the most prevalent. Among the first-line anti-TB drugs, isoniazid (INH) is primarily responsible for the occurrence of DILI. INH is metabolized in the liver by the enzymes N-acetyltransferase-2 (NAT2) and Cytochrome P450 2E1 (CYP2E1). Based on the previous studies, we hypothesized that the interactions between slow CYP2E1 genotype and NAT2 slow acetylators will induce DILI in TB patients.

METHODS

In this cross-sectional study, all 377 participants completed their anti-TB treatment, and we genotyped SNPs: rs1041983, rs1801280, rs1799929, rs1799930, rs1208, and rs1799931 for NAT2 and rs3813867 and rs2031920 for CYP2E1.

RESULTS

We found that rapid, intermediate, and slow NAT2 acetylator were 15%, 38%, and 47%, respectively, in the general population. Intermediate NAT2 acetylator is the least prevalent among patients with adverse reactions (p = 0.024). We did not confirm our hypothesis, however, we found that the combination of intermediate NAT2 acetylators and CYP2E1 c1/c1 genotype significantly protected (OR = 0.16; p = 0.049) against the development of DILI in our population.

CONCLUSION

We propose that the presence of NAT2 intermediate and CYP2E1 c1/c1 genotype could help in therapeutic drug monitoring, and optimize its therapeutic benefits while minimizing its risk for side effects or toxicity.

Clinical characteristics and outcomes of drug-induced liver injury in Taiwan: With emphasis on the impact of chronic hepatitis B infection

BACKGROUND

Whether hepatitis B virus (HBV) infection can affect the outcomes of drug-induced liver injury (DILI) is controversial. This study aimed to evaluate the characteristics and outcomes of DILI in Taiwan, with an emphasis on the impact of HBV infection.

METHODS

We prospectively recruited patients with DILI from multiple centers in Taiwan from 2010 to 2018.

RESULTS

A total of 1,014 patients were enrolled. The leading culprit drug category was antimicrobials (481, 47.4%), followed by nonsteroidal anti-inflammatory drugs, anticonvulsants, and statins. Among the antimicrobials, antituberculosis agents were most likely to induce liver injury (257, 25.3%), followed by antibacterial, antifungal, and antiviral agents. The liver-related mortality rate was 8.2% (83/1,014). The patients who died had higher rates of hepatocellular-type liver injury, elevated liver biochemical tests, preexisting liver cirrhosis, jaundice, chronic HBV infection, and antituberculosis drug-induced liver injury (ATDILI) than the survivors. A total of 131 patients (12.9%) with DILI were HBV carriers, of whom 23 (17.6%) died of hepatic failure. The rate of HBV-DNA > 2000 IU/mL was higher in the patients who died (47.8% vs. 26.9%, p = 0.047) than in the survivors. After adjusting for possible risk factors, active HBV infection with HBV-DNA > 2000 IU/mL was the most significant risk factor for liver-related mortality (adjusted HR, 4.40, 95% CI, 2.31%-8.38%, p < 0.001). The other independent risk factors for mortality were ATDILI and albumin-bilirubin (ALBI) score (adjusted HR, 1.25 and 4.09, respectively, p < 0.003).

CONCLUSION

Antituberculosis agents were the leading cause of DILI in Taiwanese, and they were associated with poorer outcomes than other drug categories. Active HBV infection, ATDILI and ALBI score were independent risk factors for fatal DILI. Close monitoring of liver tests and timely antiviral therapy should be implemented in HBV carriers during the administration of high-risk drugs, such as antituberculosis agents.

Prevalence of hepatitis B surface antigen and hepatitis B core antibody among adults with latent tuberculosis infection

OBJECTIVE

To evaluate the prevalence of hepatitis B surface antigen (HBsAg) positive or hepatitis B core antibody total (anti-HBc) among adults with latent tuberculosis infection (LTBI) in the USA.

METHODS

Using data from the National Health and Nutrition Examination Survey 1999-2000 and 2011-2012 cycles, US adults with LTBI (identified by positive tuberculin skin test or positive QuantiFERON-TB Gold In-Tube test) were evaluated to determine prevalence HBsAg and anti-HBc. Survey-weighted data was used to determine prevalence estimates of HBsAg or anti-HBc, which were further stratified by sex, race/ethnicity, country of birth and age. Trends were analyzed by regressing the outcome over time. Between-group comparisons used chi-squared testing.

RESULTS

Overall prevalence of LTBI was 4.2% [95% confidence interval (CI), 3.5-5.1]. Among individuals with LTBI, HBsAg prevalence was 0.9% (95% CI, 0.4-2.1) and anti-HBc prevalence was 12.9% (95% CI, 9.8-16.8), both of which remained stable between 1999-2000 and 2011-2012. While no significant differences in HBsAg prevalence were observed by sex, race/ethnicity, country of birth, age, anti-HBc prevalence was significantly higher in men vs. women (16.8 vs. 7.9%, P < 0.05), blacks vs. non-Hispanic whites (22.9 vs. 5.9%, P < 0.05), non-US born vs. US-born (15.9 vs. 7.2%, P = 0.01) and highest in the oldest age group (age ≥65 years: 17.5%, 95% CI, 10.5-27.8).

CONCLUSION

Among US adults with LTBI, overall prevalence of HBsAg was 0.9%. One in eight individuals with LTBI had prior HBV exposure. Effective HBV screening among individuals with LTBI may allow changes in clinical practice to prevent drug-induced liver injury from anti-TB therapies.

Circulatory Inflammatory Mediators in the Prediction of Anti-Tuberculous Drug-Induced Liver Injury Using RUCAM for Causality Assessment

BACKGROUND

Anti-tuberculous (TB) medications are common causes of drug-induced liver injury (DILI). Limited data are available on systemic inflammatory mediators as biomarkers for predicting DILI before treatment. We aimed to select predictive markers among potential candidates and to formulate a predictive model of DILI for TB patients.

METHODS

Adult active TB patients from a prospective cohort were enrolled, and all participants received standard anti-tuberculous treatment. Development of DILI, defined as ≥5× ULN for alanine transaminase or ≥2.6× ULN of total bilirubin with causality assessment (RUCAM, Roussel Uclaf causality assessment method), was regularly monitored. Pre-treatment plasma was assayed for 15 candidates, and a set of risk prediction scores was established using Cox regression and receiver-operating characteristic analyses.

RESULTS

A total of 19 (7.9%) in 240 patients developed DILI (including six carriers of hepatitis B virus) following anti-TB treatment. Interleukin (IL)-22 binding protein (BP), interferon gamma-induced protein 1 (IP-10), soluble CD163 (sCD163), IL-6, and CD206 were significant univariable factors associated with DILI development, and the former three were backward selected as multivariable factors, with adjusted hazards of 0.20 (0.07-0.58), 3.71 (1.35-10.21), and 3.28 (1.07-10.06), respectively. A score set composed of IL-22BP, IP-10, and sCD163 had an improved area under the curve of 0.744 (p < 0.001).

CONCLUSIONS

Pre-treatment IL-22BP was a protective biomarker against DILI development under anti-TB treatment, and a score set by additional risk factors of IP-10 and sCD163 employed an adequate DILI prediction.

Hepatotoxicity during TB treatment in people with HIV/AIDS related to NAT2 polymorphisms in Pernambuco, Northeast Brazil

INTRODUCTION AND OBJECTIVE

Hepatotoxicity during tuberculosis (TB) treatment is frequent and may be related to the Arylamine N-Acetyltransferase (NAT2) acetylator profile, in which allele frequencies differ according to the population. The aim of this study was to investigate functional polymorphisms in NAT2 associated with the development of hepatotoxicity after initiating treatment for TB in people living with HIV/AIDS (PLWHA) in Pernambuco, Northeast Brazil.

MATERIAL AND METHODS

This was a prospective cohort study that investigated seven single nucleotide polymorphisms located in the NAT2 coding region in 173 PLWHA undergoing TB treatment. Hepatotoxicity was defined as elevated aminotransferase levels and identified as being three times higher than it was before initiating TB treatment, with associated symptoms of hepatitis. A further 80 healthy subjects, without HIV infection or TB were used as a control group. All individuals were genotyped by direct sequencing.

RESULTS

The NAT2*13A and NAT2*6B variant alleles were significantly associated with the development of hepatotoxicity during TB treatment in PLWHA (p<0.05). Individual comparisons between the wild type and each variant genotype revealed that PLWHA with signatures NAT2*13A/NAT2*13A (OR 4.4; CI95% 1.1-18.8; p 0.037) and NAT2*13A/NAT2*6B (OR 4.4; CI95% 1.5-12.7; p 0.005) significantly increased the risk of hepatotoxicity.

CONCLUSION

This study suggests that NAT2*13A and NAT2*6B variant alleles are risk factors for developing hepatotoxicity, and PLWHA with genotypes NAT2*13A/NAT2*13A and NAT2*13A/NAT2*6B should be targeted for specific care to reduce the risk of hepatotoxicity during treatment for tuberculosis.

Antiviral Therapy for Hepatitis B Prevents Liver Injury in Patients With Tuberculosis and Hepatitis B Coinfection

BACKGROUND

Chronic hepatitis B virus (HBV) infection increases the risk of liver injury in patients who undergo antituberculosis treatment. It is uncertain whether antiviral treatment for HBV at the time of tuberculosis diagnosis would reduce the risk of liver injury.

METHODS

We performed a population-level, retrospective, cohort study that involved all patients with tuberculosis-HBV coinfection treated in public hospitals in Hong Kong over a 16-year period. Patients who received antiviral treatment at the time of tuberculosis diagnosis were considered "patients on antiviral therapy." A multivariable Cox proportional hazards model was used to determine the adjusted hazard ratio of hospitalization due to drug-induced liver injury within 1 year in patients on antiviral therapy, adjusting for the propensity score.

RESULTS

Of 3698 patients with tuberculosis-HBV coinfection, 488 (13.2%) were patients on antiviral therapy. Of the remaining 3210 patients, 446 (13.9%) started antiviral therapy within 1 year of tuberculosis diagnosis. Adjusting for the propensity score, patients on antiviral therapy had a lower risk of hospitalization due to drug-induced liver injury compared with those not on treatment (adjusted hazard ratio, 0.44; 95% confidence interval .26-.72). Compared with patients who started antiviral therapy within 1 year of tuberculosis diagnosis, patients on antiviral therapy also had a lower risk of hospitalization due to drug-induced liver injury and a lower risk of liver-related mortality.

CONCLUSIONS

We show that antiviral treatment for HBV given at the time of tuberculosis diagnosis reduced the risk of liver injury in tuberculosis-HBV coinfected patients.

Alanine transaminase and hemoglobin appear to predict the occurrence of antituberculosis medication hepatotoxicity; findings and implications in Botswana

OBJECTIVE

Tuberculosis (TB) remains a global health problem, with medications having adverse effects including drug-induced hepatotoxicity. We determined the prevalence of anti-tuberculosis drug-induced hepatotoxicity and associated risk factors.

METHODS

Retrospective cross-sectional study in Botswana including TB patients admitted from 1 June 2017 to 30 June 2018. Anti-TB drug-induced hepatotoxicity was categorized according to WHO criteria whereas causality assessment was made according to the updated Roussel Uclaf Causality Assessment Method (RUCAM) scale. The association between hepatotoxicity and included variables was undertaken by binary logistic regression.

RESULTS

Out of 112 patient files, 15 (13.4%) developed hepatotoxicity after an average of 20.4 days from the start of treatment. Grade 3 and 4 hepatotoxicity was found in 66.7% of the cases. According to the updated RUCAM tool, 86.7% of patients were categorized as having possible anti-TB-associated hepatotoxicity. Patients with elevated baseline alanine transaminase (ALT) were more likely to develop hepatotoxicity (OR = 3.484, 95% CI = 1.02-11.90). Patients with normal hemoglobin (Hb ≥ 12 g/dl) were also more likely to develop hepatotoxicity (OR = 4.413, 95% CI = 1.160-14.8).

CONCLUSION

Overall, normal hemoglobin and elevated baseline ALT levels were significantly associated with anti-TB drug-induced hepatotoxicity. Additional research is needed to explore this association further.

The role of hepatitis B infection in anti-tuberculosis drug-induced liver injury: a meta-analysis of cohort studies

Drug-induced liver injury (DILI) is a common adverse drug reaction leading to the interruption of tuberculosis (TB) therapy. We aimed to identify whether the hepatitis B virus (HBV) infection would increase the risk of DILI during first-line TB treatment. A meta-analysis of cohort studies searched in PubMed, Web of Science and China National Knowledge Infrastructure was conducted. Effect sizes were reported as risk ratios (RRs) and 95% confidence intervals (CIs) and calculated by R software. Sixteen studies with 3960 TB patients were eligible for analysis. The risk of DILI appeared to be higher in TB patients co-infected with HBV (RR 2.66; 95% CI 2.13–3.32) than those without HBV infection. Moreover, patients with positive hepatitis B e antigen (HBeAg) were more likely to develop DILI (RR 3.42; 95% CI 1.95–5.98) compared to those with negative HBeAg (RR 2.30; 95% CI 1.66–3.18). Co-infection with HBV was not associated with a higher rate of anti-TB DILI in latent TB patients (RR 4.48; 95% CI 0.80–24.99). The effect of HBV infection on aggravating anti-TB DILI was independent of study participants, whether they were newly diagnosed with TB or not. Besides, TB and HBV co-infection patients had a longer duration of recovery from DILI compared to non-co-infected patients (SMD 2.26; 95% CI 1.87–2.66). To conclude, the results demonstrate that HBV infection would increase the risk of DILI during TB therapy, especially in patients with positive HBeAg, and close liver function monitoring is needed for TB and HBV co-infection patients.

2020 Taiwan consensus statement on the management of hepatitis C: Part (II) special populations

Hepatitis C virus (HCV) infection is a silent killer that leads to rapid progression of liver cirrhosis and hepatocellular carcinoma (HCC). High prevalence of HCV infection has been reported in Taiwan, especially in high-risk populations including people who inject drugs (PWID) and patients requiring dialysis. Besides, certain populations merit special considerations due to suboptimal outcome, potential drug-drug interaction, or possible side effect. Therefore, in the second part of this 2-part consensus, the Taiwan Association for the Study of the Liver (TASL) proposes the treatment recommendations for the special population in order to serve as guidance to optimizing the outcome in the direct-acting antiviral (DAA) era. Special populations include patients with acute or recent HCV infection, previous DAA failure, chronic kidney disease, decompensated cirrhosis, HCC, liver and other solid organ transplantations, receiving an HCV viremic organ, hepatitis B virus (HBV) and HCV dual infection, HCV and human immunodeficiency virus (HIV) coinfection, active tuberculosis infection, PWID, bleeding disorders and hemoglobinopathies, children and adolescents, and pregnancy. Moreover, future perspectives regarding the management of hepatitis C are also discussed and summarized in this consensus statement.

Hepatitis C Virus Affects Tuberculosis-Specific T Cells in HIV-Negative Patients

The occurrence of tuberculosis (TB) and hepatitis C virus (HCV) infections in the same patient presents a unique clinical challenge. The impact of HCV infection on the immune response to TB remains poorly investigated in TB⁺/HCV⁺ patients. This study was conducted to evaluate the impact of HCV on the T-cell-mediated immune response to TB in coinfected patients. Sixty-four patients with active TB infections were screened for coinfection with HCV. The expression of immune activation markers IFN-γ, CD38, and HLA-DR on TB-specific CD4⁺ T cells was evaluated by flow cytometry in TB-monoinfected patients, TB/HCV-coinfected patients, and healthy controls. IL-2, IL-4, IFN-γ, TNF-α, and IL-10 levels were measured using ELISA. The end-of-treatment response to anti-TB therapy was recorded for both patient groups. Significantly lower levels of CD4⁺IFN-γ⁺CD38⁺ and CD4⁺IFN-γ⁺HLA-DR⁺ T cells were detected in TB/HCV-coinfected patients compared to TB monoinfected patients and controls. TB⁺/HCV⁺-coinfected patients showed higher serum levels of IL-10. The baseline frequencies of TB-specific activated T-cell subsets did not predict the response to antituberculous therapy in TB⁺/HCV⁺ patients. We concluded that different subsets of TB-specific CD4⁺ T cells in TB/HCV-infected individuals are partially impaired in early-stage HCV infection. This was combined with increased serum IL-10 level. Such immune modulations may represent a powerful risk factor for disease progression in patients with HCV/TB coinfection.

Impact of nucleic acid amplification test on pulmonary tuberculosis notifications and treatments in Taiwan: a 7-year single-center cohort study

BACKGROUND

Nucleic acid amplification tests (NAAT) have been used as a diagnostic tool for pulmonary tuberculosis (PTB) in Taiwan for many years. In accordance with Taiwanese legislation, health care personnel are required to notify the Centers for Disease Control and Prevention (CDC) in case of suspected PTB. This study aimed to investigate the impact of NAAT(Gen-Probe) on the notification system for PTB and anti-tuberculosis treatments in Taiwan.

METHODS

A retrospective study on the impact of NAAT (Enhanced Amplified Mycobacterium tuberculosis Direct Test [E-MTD], Gen-Probe, San Diego, CA, USA) [NAAT(Gen-Probe)] was carried out at Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation from March 2011 to December 2017. During the study period, microscopic acid-fast-bacilli smears and mycobacterial cultures were available for PTB diagnosis. NAAT(Gen-Probe) was first introduced at the hospital in January 2014 for use as a diagnostic method for PTB. Positive sputum culture was considered as the gold standard for PTB diagnosis. We excluded clinically-diagnosed PTB cases.

RESULTS

When NAAT(Gen-Probe) was applied, the rate of error notification to CDC decreased from 64.3 to 7.0% (P < 0.001), and unnecessary anti-TB treatments administered to suspected cases decreased from 14.9 to 6.5% (P = 0.005). In the non-PTB group, the mean duration of unnecessary anti-TB treatments changed from 38.9 ± 38.3 days to 37.0 ± 37.9 days (P = 0.874). In the PTB group, the mean time from notifying CDC to initiating treatment decreased from 3.05 ± 6.95 days to 1.48 ± 1.99 days (P = 0.004). The sensitivity, specificity, positive predictive value, and negative predictive value of NAAT(Gen-Probe) were 99.0, 92.3, 99.0, and 92.3%, respectively.

CONCLUSIONS

Use of NAAT(Gen-Probe) led to decrease in the rate of error notification of suspected PTB cases to the CDC, avoidance of unnecessary use of anti-TB treatments, and accelerated initiation of appropriate treatments.

Mitochondrial DNA Variants in Patients with Liver Injury Due to Anti-Tuberculosis Drugs

BACKGROUND

Hepatotoxicity is the most severe adverse effect of anti-tuberculosis therapy. Isoniazid's metabolite hydrazine is a mitochondrial complex II inhibitor. We hypothesized that mitochondrial DNA variants are risk factors for drug-induced liver injury (DILI) due to isoniazid, rifampicin or pyrazinamide.

METHODS

We obtained peripheral blood from tuberculosis (TB) patients before anti-TB therapy. A total of 38 patients developed DILI due to anti-TB drugs. We selected 38 patients with TB but without DILI as controls. Next-generation sequencing detected point mutations in the mitochondrial DNA genome. DILI was defined as ALT ≥5 times the upper limit of normal (ULN), or ALT ≥3 times the ULN with total bilirubin ≥2 times the ULN.

RESULTS

In 38 patients with DILI, the causative drug was isoniazid in eight, rifampicin in 14 and pyrazinamide in 16. Patients with isoniazid-induced liver injury had more variants in complex I's NADH subunit 5 and 1 genes, more nonsynonymous mutations in NADH subunit 5, and a higher ratio of nonsynonymous to total substitutions. Patients with rifampicin- or pyrazinamide-induced liver injury had no association with mitochondrial DNA variants.

CONCLUSIONS

Variants in complex I's subunit 1 and 5 genes might affect respiratory chain function and predispose isoniazid-induced liver injury when exposed to hydrazine, a metabolite of isoniazid and a complex II inhibitor.

Prophylactic antiviral treatment reduces the incidence of liver failure among patients coinfected with Mycobacterium tuberculosis and hepatitis B virus

BACKGROUND

China has a high prevalence of tuberculosis and hepatitis B virus infection. The purpose of this study was to determine whether HBV coinfection increases the risk of incidence of drug-induced hepatotoxicity among patients on anti-tuberculosis therapy.

METHODS

This retrospective study was carried out at the First Affiliated Hospital, School of Medicine, Zhejiang University, from 2013 to 2017. All enrolled patients were confirmed HBsAg-positive for a duration of at least 6 months and coinfected with mycobacterium tuberculosis.

RESULTS

A cohort of 90 patients was analyzed. The incidence of liver damage and liver failure was 51.11% (n = 46) and 22.22% (n = 20), respectively. By multivariate analysis, initial albumin <35 g/l (P = 0.004, odds ratio 6.162, 95% confidence interval 1.767-21.486) was an independent risk factor for liver failure, but prophylactic antiviral treatment (P < 0.001, odds ratio 0.033, 95% confidence interval 0.007-0.154) was an independent protective factor for liver failure. Of the 90 patients, 20 developed liver failure, none of the patients with liver failure received prophylactic antiviral therapy, and 6 of those patients died of liver failure.

CONCLUSIONS

Prophylactic antiviral treatment reduces the incidence of liver failure in patients coinfected with Mycobacterium tuberculosis and hepatitis B virus; therefore, it is recommended that prophylactic antiviral treatment be administered while receiving anti-tuberculosis treatment in patients coinfected with Mycobacterium tuberculosis and hepatitis B virus.

Isoniazid Concentration and NAT2 Genotype Predict Risk of Systemic Drug Reactions during 3HP for LTBI

Weekly rifapentine and isoniazid therapy (known as 3HP) for latent tuberculosis infection (LTBI) is increasingly used, but systemic drug reactions (SDR) remain a major concern. Methods: We prospectively recruited two LTBI cohorts who received the 3HP regimen. In the single-nucleotide polymorphism (SNP) cohort, we collected clinical information of SDRs and examined the NAT2, CYP2E1, and AADAC SNPs. In the pharmacokinetic (PK) cohort, we measured plasma drug and metabolite levels at 6 and 24 h after 3HP administration. The generalised estimating equation model was used to identify the factors associated with SDRs. Candidate SNPs predicting SDRs were validated in the PK cohort. A total of 177 participants were recruited into the SNP cohort and 129 into the PK cohort, with 14 (8%) and 13 (10%) in these two cohorts developing SDRs, respectively. In the SNP cohort, NAT2 rs1041983 (TT vs. CC+CT, odds ratio [OR] [95% CI]: 7.00 [2.03–24.1]) and CYP2E1 rs2070673 (AA vs. TT+TA, OR [95% CI]: 3.50 [1.02–12.0]) were associated with SDR development. In the PK cohort, isoniazid level 24 h after 3HP administration (OR [95% CI]: 1.61 [1.15–2.25]) was associated with SDRs. Additionally, the association between the NAT2 SNP and SDRs was validated in the PK cohort (rs1041983 TT vs. CC+CT, OR [95% CI]: 4.43 [1.30–15.1]). Conclusions: Isoniazid played a role in the development of 3HP-related SDRs. This could provide insight for further design of a more optimal regimen for latent TB infection.

Prevalence of Hepatitis C Virus in Tuberculosis Patients: A Systematic Review and Meta-Analysis

Background

Infection with Hepatitis C Virus (HCV) increases the hepatotoxicity of anti-tuberculosis drugs. The purpose of this systematic review and meta-analysis is to determine the prevalence of HCV infection in patients with tuberculosis (TB).

Methods

PubMed/MEDLINE, ISI/Web of Sciences, CINAHL, EMBASE, the Cochrane Library and Scopus were searched from January 2000 to March 2018. The overall prevalence of HCV in patients with TB was calculated using the random-effect model with 95% confidence interval (CI). To evaluate heterogeneity, I₂ test was used. Egger's regression test was utilized to check publication bias.

Results

Twenty-one articles were selected for the final analysis based on the inclusion/exclusion criteria. A total of 15,542 patients with TB participated in the studies. The overall prevalence of HCV infection in patients with TB was 7% [95%CI: 6–9]. Subgroup analysis revealed that diagnostic test (P=0.0039), geographical background (P=0.0076) and gender distribution (P=0.0672) were statistically significant moderators. Men had a higher risk for HCV than women (Odds Ratio, OR=2.02; 95%CI: 1.28–3.18).

Conclusion

The results of this study highlighted the importance of screening HCV in TB patients. Knowing whether HCV is present or not in these patients can be helpful in effectively treating them.

NAT2 variants and toxicity related to anti-tuberculosis agents: a systematic review and meta-analysis

BACKGROUND

Tuberculosis (TB) patients receiving anti-tuberculosis treatment may experience serious adverse drug reactions (ADRs) such as hepatotoxicity. Variants of the N-acetyltransferase 2 (NAT2) gene may increase the risk of experiencing such toxicity events.

OBJECTIVE

To provide a comprehensive evaluation of the evidence base for associations between NAT2 variants and anti-tuberculosis drug-related toxicity.

METHOD

This was a systematic review and meta-analysis. We searched for studies in Medline, PubMed, EMBASE, BIOSIS and Web of Science. We included data from 41 articles (39 distinct cohorts of patients). We pooled effect estimates for each genotype on each outcome using meta-analyses stratified by country.

RESULTS

We assessed the quality of the included studies, which was variable, with many areas of concern. Slow/intermediate NAT2 acetylators were statistically significantly more likely to experience hepatotoxicity than rapid acetylators (OR 1.59, 95%CI 1.26-2.01). Heterogeneity was not detected in the overall pooled analysis (I² = 0%). NAT2 acetylator status was significantly associated with the likelihood of experiencing anti-tuberculosis drug-related hepatotoxicity.

CONCLUSION

We encountered several challenges in performing robust syntheses of data from pharmacogenetic studies, and we outline recommendations for the future reporting of pharmacogenetic studies to enable high-quality systematic reviews and meta-analyses to be performed.

CYP genetic variants and toxicity related to anti-tubercular agents: a systematic review and meta-analysis

BACKGROUND

Treatment with anti-tuberculosis drugs may cause patients to experience serious adverse effects. Genetic factors, such as polymorphisms of CYP genes, may increase the likelihood of a patient experiencing such adverse drug reactions. In this systematic review and meta-analysis, we synthesised evidence for associations between CYP genetic variants and anti-tuberculosis drug-related toxicity outcomes.

METHODS

We searched MEDLINE, PubMed, EMBASE, BIOSIS and Web of Science to identify relevant studies. We performed meta-analyses to obtain an effect estimate for each genetic variant on each outcome, and stratified all analyses by country. We qualitatively assessed the methodological quality of the included studies.

RESULTS

We included data from 28 distinct cohorts of patients in the review. We identified many areas of concern with regard to the quality of included studies. Patients with homozygous mutant-type or heterozygous genotype at the CYP2E1 RsaI polymorphism were significantly less likely to experience hepatotoxicity than patients with homozygous wild-type genotype (odds ratio [OR] = 0.75, 95% confidence interval [CI] 0.56-1.00; p = 0.047, I2 = 58.2%). No significant differences were observed for the CYP2E1 DraI and PstI polymorphisms. For the 96-bp deletion-insertion single-nucleotide polymorphism (SNP) of the CYP2E1 gene, homozygous mutant-type significantly increased hepatotoxicity risk compared with homozygous wild-type (OR = 8.20, 95% CI 1.38-48.68, I2 = 0%); no significant difference was observed for heterozygous genotype compared with homozygous wild-type (OR = 0.77, 95% CI 0.19-3.21, I2 = 0%).

CONCLUSIONS

Generally, we identified that coverage of the association between SNPs of CYP genes and anti-tuberculosis drug-related toxicity outcomes is incomplete. We observed significant associations between the RsaI and 96-bp deletion-insertion SNPs of the CYP2E1 gene and anti-tuberculosis drug-related hepatotoxicity. We were unable to comment on the impact of ethnicity on the investigated associations, as information on participants' ethnicity was sparsely reported in the included studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42017068448.

Oxidative Stress and First-Line Antituberculosis Drug-Induced Hepatotoxicity

Hepatotoxicity induced by antituberculosis drugs is a serious adverse reaction with significant morbidity and even, rarely, mortality. This form of toxicity potentially impacts the treatment outcome of tuberculosis in some patients. Covering only first-line antituberculosis drugs, this review addresses whether and how oxidative stress and, more broadly, disturbance in redox homeostasis alongside mitochondrial dysfunction may contribute to the hepatotoxicity induced by them. Risk factors for such toxicity that have been identified, in addition to genetic factors, principally include old age, malnutrition, alcoholism, chronic hepatitis C and chronic hepatitis B infection, HIV infection, and preexisting liver disease. Importantly, these comorbid conditions are associated with oxidative stress. Thus, the shared pathogenetic mechanism(s) for liver injury might be in operation due to disease-drug interaction. Our current ability to predict, prevent, or treat hepatotoxicity (other than removing potentially hepatotoxic drugs) remains limited. More translational research to unravel the pathogenesis, inclusive of the underlying molecular basis, regarding antituberculosis drug-induced hepatotoxicity is needed, and so is clinical research pertaining to the advances in therapy with antioxidants and drugs related to antioxidants, especially those for management of mitochondrial dysfunction. The role of pharmacogenetics in the clinical management of drug-induced hepatotoxicity also likely merits further evaluation.

Co-infection with hepatitis B virus among tuberculosis patients is associated with poor outcomes during anti-tuberculosis treatment

BACKGROUND

Tuberculosis (TB) and chronic Hepatitis B virus (HBV) infection are common in China. Fist-line anti-TB medications often produce drug-induced liver injury (DILI). This study sought to investigate whether TB patients with chronic HBV co-infection are more susceptible to liver failure and poor outcomes during anti-TB treatment.

METHODS

Eighty-four TB patients developed DILI during anti-TB treatment and were enrolled, including 58 with chronic HBV co-infection (TB-HBV group) and 26 with TB mono-infection (TB group). Clinical data and demographic characteristics were reviewed. The severity of DILI and incidences of liver failure and death were compared. Risk factors of clinical outcomes were defined.

RESULTS

The patterns of DILI were similar in both groups. Compared with patients in the TB group, patients in the TB-HBV group who did not receive anti-HBV therapy before anti-TB treatment were more susceptible to Grade-4 severity of DILI (36.2% vs. 7.7%, P = 0.005), liver failure (67.2% vs. 38.5%, P = 0.013) and poor outcomes (37.9% vs. 7.7%, P = 0.005). Age > 50 years (48.1% vs. 22.6%, P = 0.049), cirrhosis (50.0% vs. 15.4%, P = 0.046) and total bilirubin > 20 mg/dl (51.6% vs. 14.8%, P = 0.005) were independent risk factors for the rate of death in the TB-HBV group, and HBV DNA > 20,000 IU/ml had borderline significance (44.1% vs. 20.8%, P = 0.081). In the TB-HBV group, nucleos(t)ide analogues as rescue therapy were not able to reduce short-term death (33.3% vs. 36.8%, P = 0.659) once liver failure had occurred.

CONCLUSIONS

Patients on anti-TB therapy with chronic HBV co-infection are more susceptible to developing liver failure and having poor outcomes during anti-TB treatment. Regular monitoring of liver function and HBV DNA level is mandatory. Anti-HBV treatment should be considered in those with high viral levels before anti-TB treatment.

Twelve-dose weekly rifapentine plus isoniazid for latent tuberculosis infection: A multicentre randomised controlled trial in Taiwan

Treatment of latent tuberculosis (TB) infection (LTBI) effectively prevents its progression to active TB. However, long treatment duration and drug-related hepatotoxicity limit the effectiveness of the 9-month daily isoniazid (9H). Data on the 3-month weekly rifapentine plus isoniazid (3 HP) in Asian populations are currently unavailable. We prospectively randomised the LTBI contacts aged ≥12 years with positive tuberculin skin test into 9H and 3 HP groups in four hospitals between January 2014 and May 2016 in Taiwan. The primary and secondary outcomes were treatment completion rate and adverse drug reactions (ADRs), respectively. Overall, 263 participants with LTBI were randomised into the 3 HP (n = 132) and 9H groups (n = 131); 14 (10.6%) and 29 (22.1%) participants in the 3 HP and 9H groups, respectively, discontinued therapy (p = 0.011). Discontinuation rates owing to ADRs were 9.1% (3 HP) and 5.3% (9H) (p = 0.241). Clinically relevant hepatotoxicity was more common in the 9H than in the 3 HP group (5.3% vs. 1.5%; p = 0.103), whereas systemic drug reaction was more common in the 3 HP than in the 9H group (3.8% vs. 0%; p = 0.060). Women had a significantly higher rate of Grade II fever than men (13.7% vs. 1.2%; p = 0.003). Compared with the 9H regimen, the 3 HP regimen had a higher completion rate with lower hepatotoxicity and well-tolerated ADR.

CLINICAL TRIALS REGISTRATION

number NCT02208427.

Acute biliary events during anti-tuberculosis treatment: hospital case series and a nationwide cohort study

Background

Tuberculosis (TB) remains one of the major infectious diseases worldwide. Adverse reactions are common during TB treatment. Few reports, however, are available on treatment-related acute biliary events (ABEs), such as cholelithiasis, biliary obstruction, acute cholecystitis, and cholangitis.

Methods

We first report four pulmonary TB patients who developed ABEs during anti-TB treatment. Abdominal sonography revealed multiple gall stones with dilated intrahepatic ducts in three patients and cholecystitis in one patient. To investigate the incidence of and risk factors for ABEs during anti-TB treatment, we subsequently conducted a nationwide cohort study using the National Health Insurance Research Database of Taiwan.

Results

A total of 159,566 pulmonary TB patients were identified from the database between 1996 and 2010, and among them, 195 (0.12%) developed ABEs within 180 days after beginning anti-TB treatment. Logistic regression analysis revealed that the risk factors associated with ABEs are older age (relative risk [RR]: 1.32 [1.21–1.44] per 10-year increment) and diabetes mellitus (RR: 1.59 [1.19–2.13]).

Conclusions

Although infrequently encountered, ABEs should be considered among patients with TB who experience abdominal discomfort with hyperbilirubinemia, especially patients who have older age or diabetes.

Prevalence of hepatitis C virus and human immunodeficiency virus in a group of patients newly diagnosed with active tuberculosis in Porto Alegre, Southern Brazil

BACKGROUND

Porto Alegre is the Brazilian state capital with second highest incidence of tuberculosis (TB) and the highest proportion of people infected with human immunodeficiency virus (HIV) among patients with TB. Hepatitis C virus (HCV) infection increases the risk of anti-TB drug-induced hepatotoxicity, which may result in discontinuation of the therapy.

OBJECTIVES

The aim of this study was (i) to estimate prevalence of HCV and HIV in a group of patients newly diagnosed with active TB in a public reference hospital in Porto Alegre and (ii) to compare demographic, behavioural, and clinical characteristics of patients in relation to their HCV infection status.

METHODS

One hundred and thirty-eight patients with TB were tested for anti-HCV antibody, HCV RNA, and anti-HIV1/2 antibody markers. HCV RNA from real-time polymerase chain reaction (PCR)-positive samples was submitted to reverse transcription and PCR amplification. The 5′ non-coding region of the HCV genome was sequenced, and genotypes of HCV isolates were determined.

FINDINGS

Anti-HCV antibody, HCV RNA, and anti-HIV antibodies were detected in 27 [20%; 95% confidence interval (CI), 13-26%], 17 (12%; 95% CI, 7-18%), and 34 (25%; 95% CI, 17-32%) patients, respectively. HCV isolates belonged to genotypes 1 (n = 12) and 3 (n = 4). Some characteristics were significantly more frequent in patients infected with HCV. Among them, non-white individuals, alcoholics, users of illicit drugs, imprisoned individuals, and those with history of previous TB episode were more commonly infected with HCV (p < 0.05).

MAIN CONCLUSIONS

HCV screening, including detection of anti-HCV antibody and HCV RNA, will be important to improving the management of co-infected patients, given their increased risk of developing TB treatment-related hepatotoxicity.

Baseline HBV load increases the risk of anti-tuberculous drug-induced hepatitis flares in patients with tuberculosis

Hepatitis associated anti-tuberculous treatment (HATT) has been a main obstacle in managing patients co-infected with Mycobacterium tuberculosis and hepatitis B virus (HBV). Therefore, we evaluated the factors related to the severity of adverse effects during HATT, especially those associated with liver failure. A retrospective study was carried out at Tongji Hospital from 2007 to 2012. Increases in serum transaminase levels of >3, 5, and 10 times the upper limit of normal (ULN) were used to define liver damage as mild, moderate, and severe, respectively. Patients with elevated total bilirubin (TBil) levels that were more than 10 times the ULN (>171 μmol/L) with or without decreased (<40%) prothrombin activity (PTA) were diagnosed with liver failure. A cohort of 87 patients was analyzed. The incidence of liver damage and liver failure was 59.8% (n=52) and 25.3% (n=22), respectively. The following variables were correlated with the severity of hepatotoxicity: albumin (ALB) levels, PTA, platelet counts (PLT), and the use of antiretroviral therapies (P<0.05). Hypo-proteinemia and antiretroviral therapy were significantly associated with liver failure, and high viral loads were a significant risk factor with an odds ratio (OR) of 2.066. Judicious follow-up of clinical conditions, liver function tests, and coagulation function, especially in patients with high HBV loads and hypoalbuminemia is recommended. It may be advisable to reconsider the use of antiviral drugs failure during the course of anti-tuberculous treatment of HBV infection patients to avoid the occurrence of furious liver failure.

Occult hepatitis B virus infection: clinical implications in tuberculosis treatment

Occult hepatitis B virus infection (OBI) is characterized by the absence of HBsAg and persistence of the virus genome (HBV-DNA) in liver tissue and/or blood. OBI has been reported in several clinical contexts. However, the clinical significance of OBI in tuberculosis (TB) treatment is unknown. We investigated the OBI prevalence and its impact on the risk of drug-induced liver injury (DILI) during TB treatment. This was a prospective cohort study with one hundred patients who were treated for TB from 2008 to 2015. Laboratory, clinical and demographic data of TB patients were extracted from medical records. Based on HBV-DNA testing of serum samples, an OBI prevalence of 12% was established; almost half of these patients had both anti-HBc and anti-HBs serological markers. Low CD4⁺ cell counts have been shown to be a risk factor for OBI among TB patients co-infected with HIV (P=.036). High DILI incidence was observed in this study. A multivariable Cox proportional hazard model was conducted and identified OBI (HR 2.98, 95% CI 1.30-6.86) as the strongest predictor for DILI when adjusted to CD4⁺ cell count (HR 0.38, 95% CI 0.17-0.90), ALT before TB treatment (HR 1.37, 95% CI 0.81-2.32) and TB extrapulmonary clinical form (HR 2.91, 95% CI 1.75-7.21). The main aim of this study was to highlight DILI as a clinical outcome during treatment of TB patients with OBI. Therefore, HBV-DNA testing should be considered routinely in monitoring DILI, and also in other clinical implications associated with OBI, reduce morbidity and mortality.

Low prevalence of hepatitis B and C among tuberculosis patients in Duhok Province, Kurdistan: Are HBsAg and anti-HCV prerequisite screening parameters in tuberculosis control program?

OBJECTIVE/BACKGROUND

Viral hepatitis, particularly hepatitis B virus (HBV) and hepatitis C virus (HCV), infections and tuberculosis (TB) are a global public health concern. Co-infection with HBV or HCV among TB patients may potentiate the risk of hepatotoxicity induced by anti-TB drugs. Hence, the aim of this study was to identify the prevalence of HBV and HCV among TB patients included in the Duhok National Tuberculosis Program (NTP).

METHODS

The Duhok NTP Center is a specialized institution in Duhok City, Iraq, concerned with management and follow-up of TB patients. A cross-sectional study was conducted at the center between June 2015 and May 2016. All documented TB patients were analyzed on the basis of socio-demographic and other characteristics. Thereafter, all patients underwent screening for hepatitis B surface antigen (HBsAg), anti-HCV, and anti-HIV using enzyme-linked immunosorbent assay (ELISA). The results obtained were analyzed by entering the data in binary format into a Microsoft Excel spreadsheet. A p value of <.05 was considered to be statistically significant.

RESULTS

Two-hundred fourteen documented TB patients were recruited in this study, with 127 (59.3%) males and 87 (40.7%) females. The mean age of the patients was 40.34years (±20.29). Of the total number of patients, four cases (1.8%) were HBsAg-positive and one case (0.9%) was positive for anti-HCV. The variables significantly associated with HBV were history of surgical dental procedure [odds ratio (OR), 0.04; 95% confidence interval (CI), -0.01 to 0.04; p=.03], and nationality (OR, 13.67; 95% CI, 0.46-210.85; p=.007).

CONCLUSION

The prevalence of HBV and HCV co-infection among TB patients in this study was low. This may be explained by the low rate of blood transfusion among the patients, the very low prevalence of HIV infections in Kurdistan, the negative history of injection drug use, and adherence to universal infection-control measures, including vaccination for HBV. Both history of dental intervention and belonging to a Syrian population were independent risk factors for HBV/TB co-infection.

Diagnosis and treatment of coinfection of pulmonary tuberculosis and chronic hepatitis B

Hepatitis B virus (HBV) and tuberculosis bacillus (TB) are leading causes of infectious diseases in China, leading to a range of life-threaten diseases including chronic hepatitis B (CHB), cirrhosis, hepatocellular carcinoma (HCC) and pulmonary tuberculosis (PTB). Due to the high prevalence of infection and increased number of cases, coinfection of HCC and PTB is becoming a new hot area. Differences between coinfection and single infection include the disease process, injuries, medication selection, curative effects, drug-resistance and side effects. In particular, the adverse effects of clinical prognosis, etiological treatment, anti-tuberculosis drug induced liver injury (ATLI) and multidrug-resistant pulmonary tuberculosis (MDR-TB) have became a new challenge for therapy. This review aims to summarize the incidence of infections, clinical observations, adversely effects and existing problems of treatment, the development of antituberculous and anti-HBV therapy and hepatitis protection. Additionally, a suggestion for improving therapeutic efficacy has been proposed as well.

Case Characterization, Clinical Features and Risk Factors in Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) caused by xenobiotics (drugs, herbals and dietary supplements) presents with a range of both phenotypes and severity, from acute hepatitis indistinguishable of viral hepatitis to autoimmune syndromes, steatosis or rare chronic vascular syndromes, and from asymptomatic liver test abnormalities to acute liver failure. DILI pathogenesis is complex, depending on the interaction of drug physicochemical properties and host factors. The awareness of risk factors for DILI is arising from the analysis of large databases of DILI cases included in Registries and Consortia networks around the world. These networks are also enabling in-depth phenotyping with the identification of predictors for severe outcome, including acute liver failure and mortality/liver transplantation. Genome wide association studies taking advantage of these large cohorts have identified several alleles from the major histocompatibility complex system indicating a fundamental role of the adaptive immune system in DILI pathogenesis. Correct case definition and characterization is crucial for appropriate phenotyping, which in turn will strengthen sample collection for genotypic and future biomarkers studies.

Epidemiology, Diagnosis and Management of Extra-Pulmonary Tuberculosis in a Low-Prevalence Country: A Four Year Retrospective Study in an Australian Tertiary Infectious Diseases Unit

OBJECTIVES

Extra-pulmonary tuberculosis (EPTB) is relatively neglected and increasing in incidence, in comparison to pulmonary tuberculosis (PTB) in low-burden settings. It poses particular diagnostic and management challenges. We aimed to determine the characteristics of EPTB in Western Sydney, Australia, and to conduct a quality assurance investigation of adherence to guidelines among Infectious Diseases (ID) practitioners managing EPTB cases.

METHODS

All adult EPTB cases managed by a large ID service during 01/01/2008-31/12/2011 were eligible for inclusion in the retrospective review. Data were extracted from patient medical records on demographic, diagnostic, clinical and management details, and on clinician adherence to local and international TB guidelines.

RESULTS

129 cases managed by the ID service were identified, with files available for 117. 98 cases were managed by the Respiratory service and were excluded. 98.2%(112/114) had been born in a country other than Australia. HIV status was tested or previously known in 97 people, and positive in 4 (4%). Microbiological confirmation was obtained in 68/117 (58.1%), an additional 24 had histopathological findings considered confirmatory (92/117, 78.6%), with the remainder diagnosed on clinical and/or radiological grounds. Median time to diagnosis post-migration from a high TB-burden country was 5 years (range 0-41). 95 cases were successfully treated, 11 cases defaulted, refused therapy or transferred, 2 cases relapsed and outcomes unknown or pending in 9 cases. No deaths occurred in the sample analysed. Clinician adherence to guidelines was high, but with scope for improvement in offering testing for co-infections, performing eye checks, monitoring blood glucose in patients receiving adjunctive corticosteroids, and considering drug interactions.

CONCLUSIONS

Despite excellent TB outcomes in this setting, the low proportion of cases with susceptibility data is worrying in this era of increasing drug resistance, and illustrates the diagnostic difficulties faced even in a well-resourced setting. Vigilance for EPTB needs to remain high in those moving from high prevalence countries to Australia, even decades after immigration.

Incidence of antituberculosis-drug-induced hepatotoxicity and associated risk factors among tuberculosis patients in Dawro Zone, South Ethiopia: A cohort study

BACKGROUND

Antituberculosis drugs cause hepatotoxicity in some individuals leading to acute liver failure, which results in death. Such phenomena limit the clinical use of drugs, contributing to treatment failure that possibly causes drug resistance. Furthermore, associated risk factors for the development of antituberculosis-drug-induced hepatotoxicity (anti-TB-DIH) are found to be controversial among different study findings.

METHODS

A prospective cohort study was conducted from May 2014 to October 2014 in Dawro Zone, Tercha District Hospital Laboratory, South Ethiopia. One hundred and twenty-four new tuberculosis-positive individuals available from Tercha Hospital and five health centers during data collection were consecutively included. The sociodemographic data and anthropometric measurement were obtained. Then, 5mL of venous blood was drawn from each individual, and the alanine transaminase, aspartate transaminase, and total bilirubin were measured photometrically at baseline, and then continuously monitored by measuring these liver enzymes every 2weeks for 2months. Data were analyzed with SPSS version 20 for Windows (SPSS Inc., Chicago, IL, USA).

RESULTS

The incidence of anti-TB-DIH was found to be 8% (10 patients out of 124). Raised serum transaminase and bilirubin level, as well as signs and symptoms of hepatotoxicity (nausea, anorexia, vomiting, malaise, and jaundice), were observed in the cases. The onset of hepatotoxicity ranged from 13days to 58days (median, 26days) after treatment was initiated. Of the various risk factors analyzed, only high alcohol intake was associated with the incidence of anti-TB-DIH (odds ratio=9.3, 95% confidence interval 1.8-47, p<.007). Age, gender, extent of tuberculosis disease, and malnutrition were not significantly associated with anti-TB-DIH.

CONCLUSION

The incidence of anti-TB-DIH in Dawro Zone was high. The drug responsible for the hepatotoxicity was not known. However, chronic high alcohol intake was associated with the development of anti-TB-DIH.

A proposal for an individualized pharmacogenetic-guided isoniazid dosage regimen for patients with tuberculosis

BACKGROUND/AIM

Isoniazid (INH) is an essential component of first-line anti-tuberculosis (TB) treatment. However, treatment with INH is complicated by polymorphisms in the expression of the enzyme system primarily responsible for its elimination, N-acetyltransferase 2 (NAT2), and its associated hepatotoxicity. The objective of this study was to develop an individualized INH dosing regimen using a pharmacogenetic-driven model and to apply this regimen in a pilot study.

METHODS

A total of 206 patients with TB who received anti-TB treatment were included in this prospective study. The 2-hour post-dose concentrations of INH were obtained, and their NAT2 genotype was determined using polymerase chain reaction and sequencing. A multivariate regression analysis that included the variables of age, sex, body weight, and NAT2 genotype was performed to determine the best model for estimating the INH dose that achieves a concentration of 3.0-6.0 mg/L. This dosing algorithm was then used for newly enrolled 53 patients.

RESULTS

Serum concentrations of INH were significantly lower in the rapid-acetylators than in the slow-acetylators (2.55 mg/L vs 6.78 mg/L, median, P<0.001). A multivariate stepwise linear regression analysis revealed that NAT2 and body weight independently affected INH concentrations: INH concentration (mg/L) = 13.821-0.1× (body weight, kg) -2.273× (number of high activity alleles of NAT2; 0, 1, 2). In 53 newly enrolled patients, the frequency at which they were within the therapeutic range of 3.0-6.0 mg/L was higher in the model-based treatment group compared to the standard treatment group (80.8% vs 59.3%).

CONCLUSION

The use of individualized pharmacogenetic-guided INH dosage regimens that incorporate NAT2 genotype and body weight may help to ensure achievement of therapeutic concentrations of INH in the TB patients.

Gender-Dimorphic Impact of PXR Genotype and Haplotype on Hepatotoxicity During Antituberculosis Treatment

Women have a higher risk of drug-induced hepatotoxicity during antituberculosis treatment (HATT) than men. We hypothesized that single nucleotide polymorphism (SNP) genotype and derived haplotype of pregnane X receptor (PXR) gene, which could regulate the expression of phase I enzyme cytochrome P450 (CYP) 3A4, had a sex-specific influence on the risk of HATT. Six SNPs of the PXR gene were sequenced. Genotypes and haplotypes of the PXR SNPs, and other potential risk factors for HATT were compared between pulmonary TB patients with and those without HATT. HATT was defined as an increase in serum transaminase level >3 times the upper limit of normal (ULN) with symptoms, or >5 times ULN without symptoms. We performed the study in a derivation and a validation cohort. Among the 355 patients with pulmonary TB in the derivation cohort, 70 (19.7%) developed HATT. Logistic regression analysis revealed the risk of HATT increased in female genotype AA at rs2461823 (OR: 6.87 [2.55-18.52]) and decreased in female genotype AA at rs7643645 (OR: 0.14 [0.02-1.02]) of PXR gene. Haplotype analysis showed that female h001101 (OR: 2.30 [1.22-4.32]) and female h000110 (OR: 2.25 [1.08-4.69]) haplotype were associated with increased HATT risk. The identified predictors were also significantly associated with female HATT risk among the 182 patients in the validation cohort. Two PXR SNP genotypes and 2 haplotypes influenced the risk of HATT only in females. The PXR SNP showed a sex-specific impact that contributed to an increased HATT risk in females.

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.

Characteristics and TB treatment outcomes in TB patients with viral hepatitis, New York City, 2000-2010

Literature surrounding the burden of and factors associated with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in persons with tuberculosis (TB) disease remains limited and focused on populations outside the USA. Cross-matched New York City (NYC) TB and viral hepatitis surveillance data were used to estimate the proportion of NYC adults diagnosed with TB from 2000 to 2010 with a report of viral hepatitis infection and to describe the impact of viral hepatitis infection on TB treatment completion and death. For 9512 TB patients, HCV infection was reported in 4.2% and HBV infection in 3.7%; <1% of TB patients had both HCV and HBV infection. The proportion of TB patients with HCV infection to die before TB treatment completion was larger than in TB patients without a viral hepatitis report (21% vs. 9%); this association remained when stratified by HIV status. There was no significant difference in death before treatment completion for TB patients with HBV infection compared to TB patients without a viral hepatitis report when stratified by HIV status. These findings reinforce the importance of hepatitis testing and providing additional support to TB patients with viral hepatitis infection.

Anti-tuberculosis drug-induced liver injury in Shanghai: validation of Hy's Law

INTRODUCTION

The most reliable liver safety signal in a clinical trial is considered to be 'Hy's Law cases' defined as subjects experiencing hepatocellular injury and serum bilirubin elevations with no more likely cause than study drug. However, there is little published data to support the current biochemical criteria for Hy's Law cases or their use to estimate postmarketing risk of severe liver injury.

OBJECTIVES

The primary objective of this study was to identify and characterize Hy's Law cases in patients treated for tuberculosis (TB). A secondary objective was to identify patient risk factors for drug-induced liver injuries.

METHODS

We utilized eDISH (evaluation of Drug-Induced Serious Hepatoxicity) to retrospectively analyze data from 517 patients treated for activeTB, a regimen well known to be capable of causing severe hepatotoxicity.

RESULTS

We identified two Hy's Law cases, which is consistent with the treatment's known risk of liver failure. Despite monthly monitoring, neither Hy's Law case experienced a documented elevation in serum alanine aminotransferase exceeding 10 × upper limits of normal. Hepatoprotectant use and infection with chronic hepatitis B were associated with increased risk of liver injury.

CONCLUSIONS

Our observations support the current biochemical criteria for Hy's Law cases and their use to estimate postmarketing risk.

The impact of HAART initiation timing on HIV-TB co-infected patients, a retrospective cohort study

BACKGROUND

Optimal timing for initiating highly active antiretroviral therapy (HAART) in HIV-TB coinfected patients is challenging for clinicians. We aim to evaluate the impact of different timing of HAART initiation on TB outcome of HIV-infected adults in Taiwan.

METHODS

A population-based retrospective cohort study was conducted through linking the HIV and TB registries of Taiwan Centers for Disease Control (CDC) during 1997 to 2006. Clinical data of HIV-TB co-infected patients, including the presence of immune reconstitution inflammatory syndrome (IRIS), was collected through medical records review. The outcome of interest was all-cause mortality within 1 year following TB diagnosis. The Cox proportional hazard model was used to explore the probability of death and IRIS after TB diagnosis by adjusting for confounding factors and factors of interest. The probability of survival and TB IRIS were calculated by the Kaplan-Meier method and compared between different HAART initiation timing groups by the log-rank test.

RESULTS

There were 229 HIV-TB co-infected patients included for analysis and 60 cases (26.2%) died within one year. Besides decreasing age and increasing CD4 lymphocyte count, having started HAART during TB treatment was significantly associated with better survival (adjusted Hazard Ratio was 0.11, 95% CI 0.06-0.21). As to the timing of HAART initiation, there was only non-significant benefit on survival among cases initiating HAART within 15 days, at 16-30 days and at 31-60 days of TB treatment than initiating after 60 days. Cases with HAART initiated after 30 days had lower risk in developing IRIS than cases with HAART initiated earlier. Cases with IRIS had significantly higher rate of re-hospitalization (49% vs. 4%, p < 0.001) and prolonged hospitalization (28 days vs. 18.5 days, p < 0.01).

CONCLUSION

The present study found that starting HAART during TB treatment is associated with better one-year survival, although earlier initiation within 60 days of TB treatment did not show statistical differences in survival than later initiation. Initiation of HAART within 30 days appeared to increase the risk of IRIS. Deferring HAART to 31-60 days of TB treatment might be optimal after considering the risks and benefits.

Hepatitis C virus co-infection increases the risk of anti-tuberculosis drug-induced hepatotoxicity among patients with pulmonary tuberculosis

BACKGROUND

The country of Georgia has a high prevalence of tuberculosis (TB) and hepatitis C virus (HCV) infection.

PURPOSE

To determine whether HCV co-infection increases the risk of incident drug-induced hepatitis among patients on first-line anti-TB drug therapy.

METHODS

Prospective cohort study; HCV serology was obtained on all study subjects at the time of TB diagnosis; hepatic enzyme tests (serum alanine aminotransferase [ALT] activity) were obtained at baseline and monthly during treatment.

RESULTS

Among 326 study patients with culture-confirmed TB, 68 (21%) were HCV co-infected, 14 (4.3%) had chronic hepatitis B virus (HBV) infection (hepatitis B virus surface antigen positive [HBsAg+]), and 6 (1.8%) were HIV co-infected. Overall, 19% of TB patients developed mild to moderate incident hepatotoxicity. In multi-variable analysis, HCV co-infection (adjusted Hazards Ratio [aHR]=3.2, 95% CI=1.6-6.5) was found to be an independent risk factor for incident anti-TB drug-induced hepatotoxicity. Survival analysis showed that HCV co-infected patients developed hepatitis more quickly compared to HCV seronegative patients with TB.

CONCLUSION

A high prevalence of HCV co-infection was found among patients with TB in Georgia. Drug-induced hepatotoxicity was significantly associated with HCV co-infection but severe drug-induced hepatotoxicity (WHO grade III or IV) was rare.

Antituberculosis treatment and hepatotoxicity in patients with chronic viral hepatitis

BACKGROUND

Whether antituberculosis (anti-TB) treatment in patients with chronic viral hepatitis affects the incidence and onset time of drug-induced hepatotoxicity (DIH) is still controversial. The aim of this retrospective study was to find out whether chronic viral hepatitis affects the incidence and onset time of DIH.

METHODS

All patients diagnosed with active TB and being treated at a tertiary referral hospital between 2002 and 2009 were identified from medical records, from which 553 patients were enrolled in the study. The incidence and onset of DIH in patients with and without chronic viral hepatitis (controls) were compared.

RESULTS

The incidence of DIH was similar in patients with and without chronic hepatitis (8 % [32/392] vs. 7 % [11/161], P > 0.05). The incidence of transient liver function impairment (TLI) was significantly lower in controls than in chronic hepatitis patients (2 % [9/392] vs. 12 % [20/161], P < 0.001. The mean onset times of DIH in the control, hepatitis B virus (HBV), and hepatitis C virus (HCV) groups were not significantly different (40, 39, and 67 days, respectively, all P > 0.05). The mean onset times of TLI in the control, HBV, and HCV groups were significantly different (23, 48, and 68 days, respectively, all P < 0.05).

CONCLUSIONS

Liver function impairment during anti-TB therapy in patients with chronic viral hepatitis was due to mostly TLI, with TLI occurring later than in controls. Chronic viral hepatitis had no significant effect on the incidence of DIH.