It has been reported that ethnicity CC-5013 can affect therapeutic response to anti-viral therapies and the long-term prognosis of patients with advanced liver diseases.15-17 In particular, it is not known whether ethnic background affects the effectiveness of rifaximin in the treatment of HE. In Korea, hepatitis B is the major cause of decompensated liver cirrhosis presenting hepatic encephalopathy, in contrast, in Western countries, liver cirrhosis secondary to alcohol abuse predominates.18,19 Alcohol overdose often leads to intestinal bacterial overgrowth which is one of the important precipitating factors of HE.20 Thus etiologic differences may affect the therapeutic efficacy of rifaximin in Korean patients with HE.

Therefore, we conducted this prospective, randomized study to determine the efficacy and tolerability of rifaximin versus lactulose for the treatment of HE in Korean patients. MATERIALS AND METHODS Patients Sixty-four in-patients with episodic HE who were admitted at Yonsei University Medical Center (Seoul, Korea) were firstly enrolled in the study. All patients were affected by decompensated liver cirrhosis and HE, which were diagnosed based on clinical and laboratory findings. Patients showed signs of the first to third degree HE, according to Conn’s modification of Parsons-Smith classification,21 and had serum ammonia levels > 75 ��mol/L.

The criteria for exclusion from the study were: an age <18 years, the presence of a major neuropsychiatric illness, presence of intestinal obstruction or inflammatory bowel disease, hypersensitivity to rifamycin or disaccharides, a serum creatinine level>twice normal, those that had received loop diuretics, antacids or cathartics within the 12 hour period preceding study commencement, patients that were on antibiotics during the preceding 7 days, and those that had been treated with encephalopathy-causing agents. Women of child-bearing age were excluded if they were not using a method of contraception. Ten of the 64 initially enrolled patients were excluded, and 54 patients finally entered the trial. The enrolled patients were 37 males and 17 females, aged between 40 and 71 (mean age 55.7 years). At the start of the study, the demographic and clinical parameters of the patients in the two groups showed no significant differences (Table 1).

Identified precipitating factors included dehydration (n=14), protein overload (n=13), constipation (n=12), bacterial infection (n=3), and unknown (n=12). There was no significant difference between the two groups in terms of factors precipitating HE (Table 2). Table 1 Clinical and Laboratory Characteristics of the Patients Table 2 Hepatic Encephalopathy Related Factors of the Patients The research was performed in accordance with the revised Helsinki Declaration, and the study protocol adopted was approved by the Yonsei University Brefeldin_A Medical Center Institutional Ethics Committee.