Antituberculosis drug-induced hepatitis is one of the most prevalent drug-induced liver injuries. Isoniazid is the major drug incriminated in this hepatotoxicity. Isoniazid is mainly metabolized to hepatotoxic intermediates by N-acetyltransferase (NAT). However, the association of polymorphic NAT acetylator status and antituberculosis drug-induced hepatitis is debatable. To determine whether acetylator status is a risk factor for antituberculosis druginduced hepatitis, we genotyped NAT2 in 224 incident tuberculosis patients who received antituberculosis treatment. Antituberculosis drug-induced hepatitis was diagnosed based on a positive isoniazid rechallenge test and exclusion of viral hepatitis. Acetylator status was determined by genotyping NAT2 in patients using a polymerase chain reaction with restriction fragment length polymorphism. Univariate analysis and logistic regression analysis were used to evaluate the risk factors of isoniazid-induced hepatitis. Thirty-three patients (14.7%) were diagnosed with antituberculosis drug-induced hepatitis. Slow acetylators had a higher risk of hepatotoxicity than rapid acetylators (26.4% vs. 11.1%, P ‫؍‬ .013). Among patients with hepatotoxicity, slow acetylators had significantly higher serum aminotransferase levels than rapid acetylators. Logistic regression showed that slow-acetylator status (odds ratio [OR], 3.66; 95% CI, 1.58-8.49; P ‫؍‬ .003) and age (OR, 1.09; 95% CI, 1.04-1.14; P < .001) were the only 2 independent risk factors for antituberculosis drug-induced hepatitis. In conclusion, slow-acetylator status of NAT2 is a significant susceptibility risk factor for antituberculosis drug-induced hepatitis. Additionally, slow acetylators are prone to develop more severe hepatotoxicity than rapid acetylators. Regular monitoring of serum aminotransferase levels is mandatory in patients receiving antituberculosis treatment, especially in slow acetylators. (HEPATOLOGY 2002;35:883-889.)

Pathways involving androgen signaling may affect the risk of HBV-related HCC among men.

In this study of moderate-to-severe plaque psoriasis, joint and nail symptoms were prevalent and patients with these symptoms had significantly greater HR-QoL impairment at baseline than unaffected patients. Etanercept provided significant improvement in symptom severity and HR-QoL.

HCC risk is associated with sequence variation in the EnhII/BCP regions of HBV, and persistence of at-risk sequence variants is critical for HCC development.

ObjectivesTo numerically and experimentally investigate the robustness of intravoxel incoherent motion (IVIM) magnetic resonance imaging in measuring perfusion indexes in the human brain.MethodsEighteen healthy volunteers were imaged on a 3 T clinical system. Data of IVIM imaging (12 b-values ranging from 0 to 1000 s/mm2, 12 repetitions) were fitted with a bi-exponential model to extract blood volume fraction (f) and pseudo-diffusion coefficient (D*). The robustness of measurement was assessed by bootstrapping. Dynamic susceptibility contrast (DSC) imaging and arterial spin-labelling (ASL) imaging were performed for cross-modal comparison. Numerical simulations were performed to assess the accuracy and precision of f and D* estimates at varied signal-to-noise ratio (SNRb1000).ResultsBased on our experimental setting (SNRb1000 ~ 30), the average error/variability is ~5 %/25 % for f and ~100 %/30 % for D* in gray matter, and ~10 %/50 % for f and ~300 %/60 % for D* in white matter. Correlation was found between f and DSC-derived cerebral blood volume in gray matter (r = 0.29 – 0.48 across subjects, p < 10-5), but not in white matter. No correlation was found between f-D* product and ASL-derived cerebral blood flow.Conclusionsf may provide noninvasive measurement of cerebral blood volume, particularly in gray matter. D* has limited robustness and should be interpreted with caution.Key Points• A minimum SNRb1000of 30 is recommended for reliable IVIM imaging.• f may provide noninvasive measurement of cerebral blood volume.• f correlates with CBVDSCin gray matter.• There is no correlation between fD* and CBFASL.• D* has limited robustness and should be interpreted with caution.