Lubiprostone plus polyethylene glycol electrolyte lavage solution (PEG-ELS) versus PEG-ELS for bowel preparation in chronic constipation: a randomized controlled trial.

Colonoscopy is considered the standard procedure for early detection and prevention of colorectal cancer. Adequate bowel cleansing is an important determinant of the efficacy of colonoscopy screening. Currently, there is no standard method of bowel preparation for patients with chronic constipation. The aim was to access the rate of adequate bowel cleansing achieved using split-dose polyethylene glycol electrolyte lavage solution (PEG-ELS) plus lubiprostone in comparison with split-dose PEG-ELS alone. A single-centre, endoscopist-blinded, randomized controlled trial was conducted. Seventy-eight constipated patients aged 18-75 years who were indicated for colonoscopy in the gastroenterology unit of Srinagarind Hospital, Khon Kaen University, between February 2020 and February 2021 were randomly allocated to receive either split-dose PEG-ELS in combination with lubiprostone (N = 39) or split-dose PEG-ELS alone (N = 39) before colonoscopy. Adequate bowel cleansing was defined as an Ottawa bowel preparation score ≤ 7. The rate of adequate bowel cleansing was comparable between the PEG-ELS plus lubiprostone group and the PEG-ELS alone group (50% vs. 52.9%, p value = 0.81) with a relative risk of 1.13 (95% CI = 0.43-2.91). There were no significant differences in adenoma detection rate (41.2% vs. 35.3%, p value = 0.62), adverse events, acceptance, compliance, or patient satisfaction between the 2 groups. No additional benefit to successful bowel preparation was achieved by the combination of lubiprostone and PEG-ELS in chronic constipation patients undergoing colonoscopy.

GERD questionnaire for diagnosis of gastroesophageal reflux disease in systemic sclerosis.

OBJECTIVES: Gastroesophageal reflux disease (GERD) is clinically-identified in patients with systemic sclerosis (SSc). The GERD-questionnaire (GERD-Q) score is a sensitive, non-invasive, diagnostic screening tool for diagnosis of GERD in general patients, but it has been not investigated for use in SSc. Our aim was to evaluate the proper cut-off GERD-Q score, sensitivity and specificity for a diagnosis of GERD in SSc patients. METHODS: A cross-sectional study using the GERD-Q was performed during May 2012-January 2013 on patients over 18 with the diffuse SSc subset. Both esophago-gastro-duodenoscopy (EGD) and 24-hr pH-monitoring (24hr-pH) were performed as the gold standard tests for both symptomatic and asymptomatic GERD. RESULTS: A total of 75 SSc patients completed the GERD-Q, EGD and 24hr-pH. We identified 22 males (29.3%), 53 females (70.7%) with a mean age of 54.2 years. The respective number of symptomatic and asymptomatic GERD was 69 and 6 cases. For a GERD diagnosis, a cut-off GERD-Q score of 4 provided the best balance between sensitivity and specificity (96.9% and 50%, respectively). Of 48 participants (69.6%) with symptomatic GERD (i.e. positive for both EGD and 24hr-pH), 65 (94.2%) were positive for either EGD or 24hr-pH, and 4 (5.8%) were negative for both EGD and 24hr-pH. A respective majority (83%) vs. one-third of the asymptomatic group had reflux as detected by 24hr-pH vs. EGD CONCLUSIONS: A GERD-Q score of 4 or higher indicates a high sensitivity for a diagnosis of GERD in SSc. It can thus be used as a non-invasive screening tool for diagnosing GERD in cases where EGD and 24hr-pH are unavailable.

Clinico-epidemiology of hepatitis C viral infection in northeastern Thailand.

Hepatitis C virus (HCV) is responsible for a large number of cases of chronic liver disease worldwide. A study of clinico-epidemiology of HCV infection was conducted in 214 patients who were seropositive for antibody to HCV (anti-HCV) in Srinagarind Hospital, Khon Kaen University, northeastern Thailand, during August 1997 to December 1998. There were 199 males, 15 females and their mean age was 34.96 +/- 9.75 years with a range from 16 to 72 years. The clinical features of acute hepatitis, chronic hepatitis, liver cirrhosis, hepatocellular carcinoma (HCC) and asymptomatic HCV infection were 2, 115, 15, 2 and 80 cases. Risk factors for HCV acquisition were intravenous drug use (IVDU), tattooing and blood transfusion in 46.7, 32.2 and 18.8% of cases, respectively. 23.36% had a history of multiple risk factors while 28.9% had no history of risk factor exposure.

Clinico-epidemiology of hepatitis B viral infection in Northeastern Thailand.

Hepatitis B viral (HBV) infection is a common disease world wide. A study of clinico-epidemiology of HBV infection was conducted in 381 patients who seropositive for hepatitis B surface antigen (HBsAg) in Srinagarind Hospital, Khon Kaen University, Northeastern Thailand, during August 1997 to December 1998. 293 males, 88 females and their mean age was 30.96 +/- 12.78 years with a range from 15 to 77 years. The clinical features of acute hepatitis, chronic hepatitis, liver cirrhosis, hepatocellular carcinoma (HCC) and asymptomatic carrier were 2.36, 34.12, 4.99, 1.05 and 57.48% of cases. Possible routes for HBV transmission were family history of hepatitis, tattooing, intravenous drug addict and blood transfusion in 20.3, 11.3, 8.2 and 6.9% of cases, respectively. Signs of chronic liver disease were common in liver cirrhosis and HCC. Acute fulminating hepatitis was not found in this study.

Relationships between the synthesis of N-nitrosodimethylamine and immune responses to chronic infection with the carcinogenic parasite, Opisthorchis viverrini, in men.

This study investigated the relationship between immune responses to infection with the liver fluke, Opisthorchis viverrini, and the synthesis of the carcinogen, N-nitrosodimethylamine (NDMA) in humans. It also examined associations between synthesis of nitric oxide (NO) and nitrosation of amines, in vivo. Antibody and T cell responses to fluke antigens and post-alcohol urinary NDMA excretion were assessed among three groups of 40-50 men with no, moderate and heavy liver fluke infection. Markers of NO synthesis (nitrate, nitrite) and nitrosation (nitrosamino acids) were also measured in biological fluids. Assessments were carried out under controlled conditions which minimised intake of exogenous nitrate and nitrite and were carried out at two time points, namely before and 4 months after elimination of the infection with praziquantel treatment. No statistically significant variation was observed in the amount of NDMA excreted between the 3 groups. However, during active infection, a strong negative association was observed between in vitro lymphoproliferative responses to some liver fluke antigens and NDMA excretion. After treatment this association was reduced. Multivariate statistical models revealed a highly significant relationship between NDMA levels and urinary nitrate, stimulation indices for two T cell responses to two parasite antigens (MW 37 kDa and 110 kDa) and gall bladder dimensions. NDMA levels after treatment were best described by the ratio between parasite-specific IgG2 and IgE, background levels of T cell proliferation, a urinary marker of nitrosation (N-nitrosothioproline) and usual level of alcohol consumption. These results suggest that individual background immunologic activity, parasite-specific responses and/or parasite products and NO synthesis are important determinants of endogenous generation of nitrosamines in O. viverrini-infected humans.

Induction of cytochrome P450 2A6 expression in humans by the carcinogenic parasite infection, opisthorchiasis viverrini.

The purpose of this study was to examine in vivo the activity of cytochrome P450 (CYP) 2A6, an enzyme capable of activating carcinogens, including N-nitrosodimethylamine, in humans with the carcinogenic liver fluke infection, opisthorchiasis viverrini, before and after treatment with the antiparasitic agent, praziquantel. Coumarin hydroxylase activity of CYP 2A6 was assessed by administering a probe drug, coumarin, and measuring its metabolite, 7-hydroxycoumarin, in urines collected between 0-2 h and 2-4 h of 106 people with varying intensities of Opisthorchis viverrini infection. Five individuals who did not excrete any detectable 7-hydroxy coumarin (and have a genetic defect probably leading to an absence of catalytic activity of the CYP 2A6 protein) were excluded from analysis. Infected people excreted an average of 22.7 mumol of 7-hydroxycoumarin in the first 2 h after taking the drug, whereas the mean of the uninfected group was 19.4 mumol; this difference did not reach statistical significance (P = 0.10). However, a highly significant increase in CYP 2A6-related activity was observed in infected individuals who also had radiological evidence of biliary fibrosis (28.1 mumol) compared to those without (19.4 mumol; P = 0.01). Reassessments of coumarin hydroxylase activity of CYP 2A6 made 2 months after praziquantel treatment showed highly significant reductions in the amount of 7-hydroxycoumarin excreted among the infected groups but no difference in the uninfected group. These results suggest that expression of CYP 2A6 is induced among chronically infected people who also have fibrosis of the intrahepatic bile duct. As already demonstrated in an animal model and now observed in humans for the first time, this increase in CYP 2A6-related enzyme activity may represent an important mechanistic link between inflammatory products of chronic liver fluke infection (e.g., DNA alkylation damage from endogenously formed N-nitrosamines) and the high risk of cholangiocarcinoma faced by infected individuals.

Cross-sectional patterns of hepatobiliary abnormalities and possible precursor conditions of cholangiocarcinoma associated with Opisthorchis viverrini infection in humans.

The liver fluke, Opisthorchis viverrini, is both highly prevalent and closely associated with cholangio-carcinoma in northeast Thailand. This study measured associations between intensity of liver fluke infection and nonmalignant hepatobiliary disease diagnosed by ultrasonography among 1, 807 largely asymptomatic adult residents drawn from endemic communities. Abnormalities significantly associated with intensity of infection included gallbladder enlargerment in all dimensions, presence of sludge, irregular gallbladder wall, liver enlargement, and enhanced portal vein radicle echoes. While gallbladder enlargement was not sex-specific, the prevalence odds of the other abnormalities were 2-3 times higher among males compared with females. Those recently treated with the anthelmintic praziquantel had higher odds of these abnormalities compared with others with the same infection status who were untreated. The low prevalence of gallstones suggests that this impairment of gallbladder structure and function does not frequently stimulate gallstone formation. However, gallbladder disturbances, together with chronic inflammation and fibrosis of the bile ducts, which are visualized as enhanced portal vein radicle echoes, may contribute to the strikingly enhanced susceptibility to cholangiocarcinoma among people, especially males, with heavy liver fluke infection.

Thiocyanate-independent nitrosation in humans with carcinogenic parasite infection.

Infection with the liver fluke, Opisthorchis viverrini, is a causative agent of cholangiocarcinoma. One possible contributing factor in this carcinogenesis is the chronic, local generation of nitric oxide by inflammatory cells expressing inducible nitric oxide synthase and the production of N-nitroso compounds via the reaction between amines and nitrosating agents derived from nitric oxide. Our previous studies provided evidence that nitric oxide synthesis is elevated during human liver fluke infection. Here we present data on the same sample of men which definitively demonstrates increased nitrosation of proline and thioproline (thiazolidine-4-carboxylic acid) among infected men compared to uninfected control subjects on a low nitrate diet. This difference was specifically abolished by co-administration of ascorbic acid with proline and by elimination of parasites by praziquantel treatment. Multivariate statistical models demonstrate the importance of salivary thiocyanate levels to variation in the nitrosation of proline among uninfected individuals, but not among those with current fluke infection. This suggests that considerable generation of nitrosating agents (N203/N204) in infected people may be occurring via oxidation of arginine by nitric oxide synthase in inflamed tissue which is thiocyanate insensitive. Analyses revealed positive associations between N-nitrosoproline excretion and nitrate/nitrite levels in urine, plasma and saliva and with usual alcohol intake; with variation in these trends between groups. In conclusion, we have confirmed the relationship between O.viverrini infection and enhanced endogenous nitrosation, showing evidence of its extragastric site. New information is also provided on the determinants of N-nitrosamino acid excretion in men on a controlled low nitrate diet without smoking, conditions which reduce exogenous sources of nitrosating agents.

Epidemiological study on contamination of water and diarrheal diseases in a rural community in northeast Thailand.

An epidemiological and bacteriological study of diarrheal diseases as well as the relation between domestic-use water and passage of enteric pathogens with stools of the villagers was performed in the northeastern rural area of Thailand on 4 different occasions during the 3 years from 1992-1994. The questionnaire study indicated that 93% of the residents used rain water stored in containers for drinking and other domestic uses, and that 28% of them filtrated and/or boiled the water before drinking it. About 90% of drinking water samples collected from the same residents showed positive responses for the preliminary test ofEscherichia coli contamination. Furthermore, a precise bacteriological survey indicated that more than half of the drinking water samples collected from containers storing rain water were contaminated with various enteropathogenic bacteria, includingE. coli, Vibrio spp. andShigella spp. The new serotype ofV. cholerae O139, synonym 'Bengal cholerae,' which could be isolated from different specimens, is replacing the traditional species ofVibrio. Forty-one per cent of the villagers carried enteropathogenic bacteria in their stools. Most of them were asymptomatic carriers and only a few of them showed clinical features of diarrhea. A few concrete propositions were discussed to supply safe water in these areas where drinkable underground water is not available.

Cross-sectional study of Opisthorchis viverrini infection and cholangiocarcinoma in communities within a high-risk area in northeast Thailand.

We describe an innovative strategy to quantify risk of cancer associated with varying levels of exposure to chronic parasitic infection through the identification of asymptomatic cases of cholangiocarcinoma within a population-based survey of Opisthorchis viverrini infection. Stool samples from 12,311 adults over age 24 years from 85 villages in northeast Thailand were examined for intensity of liver fluke infection. People from varying egg count categories were selected for ultrasound examination to identify hepatobiliary disease. Fifteen preclinical cases of cholangiocarcinoma were diagnosed from a total of 1,807 people based on ultrasonographic evidence with confirmation by endoscopy where possible. The prevalence odds of the diagnosis of cholangiocarcinoma increased gradually within the light and moderate intensity groups. In contrast, sharply elevated prevalence odds [age-, sex- and locality-adjusted prevalence odds ratio (POR) 14.1, p < 0.05] were observed within the most heavily liver fluke-infected group compared with the uninfected group. Males were more frequently affected than females (crude POR 4.5), but after controlling for intensity of infection, age and locality, the magnitude and significance of this measurement was reduced. Our data clearly demonstrate a significant relationship between intensity of liver fluke infection and cholangiocarcinoma and a strikingly high prevalence of the disease among heavily infected males.

Parasite-associated morbidity: liver fluke infection and bile duct cancer in northeast Thailand.

Infection with the liver fluke, Opisthorchis viverrini, remains a major public health problem in Northeast Thailand, where approximately one-third of the population is infected. The northeast region is largely populated by Laos-descendent Thais who enjoy eating raw fish, which harbour the infective stage of the fluke. The parasite has maintained its presence in the population despite the widespread use of praziquantel and dissemination of health education material throughout the region by vigorous government-sponsored programs in recent years. The most severe consequence of liver fluke infection is cholangiocarcinoma, i.e. cancer of the bile duct epithelium. Although mortality due to the parasites alone appears to be uncommon, cholangiocarcinoma arising as a result of infection is one of the leading causes of death in the region. This paper reviews the pathogenesis of infection and the geographic, hospital-based and community studies which demonstrate the close relationship between infection and cancer. In addition, data from the Cancer Registry of Khon Kaen, Northeast Thailand and population-based studies using ultrasonography to visualize early tumours which illuminate the very high frequency of the cancer among heavily infected individuals and communities are discussed. Finally, the paper will close with a brief commentary on the prospects for control of the parasite and its likely impact on the frequency of cancer given the current epidemiological situation of liver fluke infection.

Liver fluke infection and cholangiocarcinoma: model of endogenous nitric oxide and extragastric nitrosation in human carcinogenesis.

Cancers arising during bacterial, viral and parasitic infection provide useful models to investigate the link between inflammation and carcinogenesis. Because the inflammatory agent is known, relationships between immune responses, the production of DNA-damaging agents, such as nitric oxide, oxygen radicles and N-nitroso compounds, and cancer risk can be explored. This paper first describes the close relationship between infection with the liver fluke, Opisthorchis viverrini, and cholangiocarcinoma in humans. Data are then presented which demonstrate an elevation in levels of salivary nitrite and urinary and plasma nitrate among men with moderate and heavy liver fluke infections compared to uninfected controls which was absent 4 months after the parasites were cleared with praziquantel. Because of the strict control over subject selection and dietary intake plus the absence of the increase following treatment, we conclude that the higher levels of nitrate and nitrite reflect endogenous generation of nitric oxide resulting from liver fluke infection. Excess nitric oxide generation in the inflamed tissue is likely to lead directly to the formation of N-nitroso compounds mediated by activated macrophages. Further work will attempt to demonstrate a link between this increase and both parasite-specific immune responses and the risk of cancer.

Reversal of biliary tract abnormalities associated with Opisthorchis viverrini infection following praziquantel treatment.

We recently demonstrated a number of biliary tract abnormalities associated with moderate to heavy Opisthorchis viverrini infection among 95 selected village residents in north-east Thailand, who were treated with praziquantel immediately after initial examination and re-examined by abdominal ultrasonography 10 months later. Dramatic improvement in the gall-bladder status of previously infected individuals was observed, including reduction of gall-bladder length and width and regained contractibility of the organ following fatty meal consumption. The frequency of severe enhanced portal vein radicle echoes and gall-bladder sludge and wall irregularities also decreased following treatment, but persisted in many individuals. Two masses were observed in the right hepatic lobe of one individual who was previously considered normal. The findings suggest that gall-bladder abnormalities are reversible following elimination of liver fluke infection, but malignancies, once initiated, are not likely to be affected by treatment.

Intestinal capillariasis: a cause of chronic diarrhea and hypoalbuminemia.

Seventeen cases of intestinal capillariasis in Srinagarind Hospital, Khon Kaen University, Thailand were reviewed. The mean age was 40.41 years with a range from 21 to 69 years. Most cases had intermittent or continuous voluminous watery diarrhea for one month to three years with hypoalbuminemia. Borborygmi, vague abdominal pain, weight loss and pedal edema were significant associated symptoms. Fecal examination was the most useful for diagnosis by finding the Capillaria philippinensis ova in all cases. Mebendazole 400 mg per day for 20 to 28 days is the treatment of choice. Usually, relapse and death are unusual, inadequate treatment is a major factor.

Human pythiosis in Srinagarind Hospital: one year's experience.

We have reported four cases of human pythiosis arteritis from Srinagarind Hospital, Khon Kaen, Thailand. This unusual human infection occurring perhaps exclusively in thalassemia and hemoglobinopathy patients, should be noted by physicians, who work in areas with a high incidence of hemoglobinopathy, and for patients who present with unexplained arterial insufficiency. As our reported cases occurred within only one year, this condition may be more common than originally suspected and found more frequently if actively searched for.

Relationship between intensity of Opisthorchis viverrini infection and hepatobiliary disease detected by ultrasonography.

Twenty-four locality-, age- and sex-matched groups of village residents with no light, moderate and heavy Opisthorchis viverrini infection were examined by ultrasonography. Highly significant differences were observed between the groups in the relative size of the left lobe of the liver and the fasting and post-meal size of the gall-bladder. In addition, indistinct gall-bladder wall, the presence of gall-bladder sludge and strongly enhanced portal vein radicle echoes were most frequently observed in the heavily infected group. Two suspected cases of cholangiocarcinoma were identified from the heavy group. The results highlight the importance of intensity of infection on the frequency and severity of fluke-associated hepatobiliary disease.

Immune responsiveness and parasite-specific antibody levels in human hepatobiliary disease associated with Opisthorchis viverrini infection.

Opisthorchis viverrini infection is associated with human hepatobiliary disease and cholangiocarcinoma, but the role of the immune response in the pathogenesis of infection is unclear. Here ultrasonography was used to examine the biliary tracts of residents from an endemic community. Delayed-type hypersensitivity responses to unrelated antigens, and fluke-specific IgG and IgA levels in serum of this group were also examined. Relationships between immunological parameters, intensity of infection and radiologically measured variables are reported. Immune responsiveness to unrelated antigens did not vary with intensity of parasite infection or disease status. Of all the variables, IgG levels were most markedly elevated in disease cases compared with normal subjects and were closely associated with gall bladder size and dysfunction. This is consistent with the hypothesis that an immunopathologic mechanism is involved in opisthorchiasis and suggests that antibody levels may be useful in screening populations for fluke-associated hepatobiliary disease.

Acute renal failure in obstructive jaundice in cholangiocarcinoma.

This study was aimed at defining the natural history of renal failure in obstructive jaundice due to cholangiocarcinoma, which is an important health problem in northeastern Thailand. Sixty-four patients among a total of 130 patients with obstructive jaundice secondary to cholangiocarcinoma who developed acute renal failure were studied retrospectively. Analysis was made with respect to clinical features, laboratory findings, and outcome. The development of renal failure before surgery was observed in all patients. It was nonoliguric in 80% and was associated with severe jaundice, gram-negative infection (42%), hypotension (31%), hypoproteinemia (30%), hyponatremia (56%), and hypokalemia (63%). The mean duration of renal failure was 2 weeks. All patients underwent surgery for the relief of jaundice. Seventy-seven percent of the patients survived and had recovery of renal function after the relief of jaundice. Twenty-three percent of the patients died of infection. Clinical data highlight the higher serum bilirubin levels and the frequent occurrence of hyponatremia, hypokalemia, and hypotension in renal failure. Their possible roles in contributing to the development of renal failure are discussed.

A high frequency of hepatobiliary disease and suspected cholangiocarcinoma associated with heavy Opisthorchis viverrini infection in a small community in north-east Thailand.

A group of 87 adults from a small village in north-east Thailand was chosen to undergo ultrasound investigation based on their intensity of infection with the liver fluke, Opisthorchis viverrini, or clinical status (history of jaundice, current hepatomegaly). From this group, 8 cases of suspected early cholangiocarcinoma were found, and the diagnostic features of 6 of the 8 were confirmed by computerized tomography scan and endoscopic retrograde cholangiopancreatography. In addition, several cases of mild gall-bladder disease, chronic cholecystitis, cholelithiasis and parenchymal liver disease were detected. A highly significant positive relationship between the intensity of liver fluke worm burden and the severity of biliary tract disease within individuals is reported. These results indicate that Opisthorchis is associated with moderate to severe hepatobiliary disease in a considerable proportion of infected individuals.