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W M Wong

Publications and source records attributed to W M Wong.

At least 19 recordsLinked to original sources
PubMed2004

Double-blind, randomized controlled study to assess the effects of lansoprazole 30 mg and lansoprazole 15 mg on 24-h oesophageal and intragastric pH in Chinese subjects with gastro-oesophageal reflux disease.

BACKGROUND: Previous studies have suggested that the acid secretory capacity of the Chinese population is lower than that of the Western population. AIM: To compare the effect of lansoprazole 30 mg and 15 mg once daily on the 24-h oesophageal and intragastric pH profiles in Chinese patients with gastro-oesophageal reflux disease. METHODS: Forty-four patients (male to female ratio, 27 : 17; mean age, 53 years; 55% with oesophagitis) with gastro-oesophageal reflux disease were randomized to receive lansoprazole 30 mg or 15 mg once daily for 4 weeks. Measurement of the 24-h oesophageal and intragastric pH, gastro-oesophageal reflux disease symptoms and quality of life was performed at baseline and during the last week of each dosing period. RESULTS: Lansoprazole 30 mg maintained an intragastric pH > 4 for 10.5 h vs. 9.6 h for lansoprazole 15 mg (P = 0.44). The percentage total time at oesophageal pH < 4 was similar for lansoprazole 30 mg and 15 mg (2.0% vs. 2.3%, P = 0.30). The proportion of patients with complete cure of heartburn and acid regurgitation and the quality of life assessment were similar for lansoprazole 30 mg and 15 mg. Both dosages of lansoprazole were well tolerated and the compliance was 100% in both groups. CONCLUSION: Lansoprazole dosages of 30 mg and 15 mg once daily provide a satisfactory decrease for oesophageal acid exposure and are equally effective for the treatment of gastro-oesophageal reflux disease in the Chinese population.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2004

The role of cholecystectomy in reducing recurrent gallstone pancreatitis.

BACKGROUND AND STUDY AIM: Endoscopic sphincterotomy (ES) or cholecystectomy can prevent recurrent acute pancreatitis (RAP) in patients with gallstone-related pancreatitis. However, it is unknown whether cholecystectomy after ES offers additional benefit in preventing RAP in these patients. This is a retrospective study to assess whether cholecystectomy can decrease the incidence of RAP in patients with gallstone-related pancreatitis. PATIENTS AND METHODS: Records from 139 patients with gallstone-related pancreatitis were analyzed. Of these, 58 patients had gallbladder stones with concomitant common bile duct (CBD) stones and 81 patients had gallbladder stones without CBD stones. Of the 58 patients who had both gallbladder and CBD stones, 37 (63.8 %) did not undergo cholecystectomy after ES (group 1) and 21 patients (36.2 %) did undergo cholecystectomy after ES (group 2). Of the 81 patients who had gallbladder stones but who did not have CBD stones, 54 (66.7 %) did not undergo cholecystectomy (group 3) and 27 (33.3 %) did undergo cholecystectomy (group 4). RESULTS: At the time of analysis, three patients (8.1 %) in group 1 and three patients (14.3 %) in group 2 developed RAP. There was no significant difference in the estimated probability of occurrence of RAP over time between group 1 and group 2 ( P = 0.41). However, there was a significantly higher probability of patients developing RAP over time in group 3 compared with group 4 (6/54 vs. 0/27 respectively, P = 0.04). CONCLUSION: In patients with gallbladder stones without CBD stones, cholecystectomy can decrease the incidence of RAP. In patients with both gallbladder and CBD stones, however, the risk of RAP was not further reduced by cholecystectomy after ES and complete removal of CBD stones.

Aged↗
PubMed2003

A sensitive guaiac faecal occult blood test is less useful than an immunochemical test for colorectal cancer screening in a Chinese population.

BACKGROUND: Colorectal cancer screening by guaiac faecal occult blood test has been shown to reduce the incidence and mortality of colorectal cancer in Western populations. The optimal faecal occult blood test, whether guaiac or immunochemical, for colorectal cancer screening in the Chinese population remains to be defined. AIM: To compare the performance characteristics of a sensitive guaiac-based faecal occult blood test (Hemoccult SENSA) and an immunochemical faecal occult blood test (FlexSure OBT) in a Chinese population referred for colonoscopy. METHODS: One hundred and thirty-five consecutive patients who were referred for colonoscopy and who met the study inclusion criteria took samples for the two faecal occult blood tests simultaneously from three successive stool specimens, with no dietary restrictions. All tests were developed and interpreted by a single experienced technician who was blind to the clinical diagnosis. The sensitivity, specificity and positive predictive value for the detection of colorectal adenomas and cancers were estimated for the two tests. RESULTS: The sensitivity, specificity and positive predictive value for the detection of significant colorectal neoplasia (adenomas > or = 1.0 cm and cancers) were 91%, 70% and 18% for Hemoccult SENSA and 82%, 94% and 47% for FlexSure OBT. The specificity and positive predictive value were significantly higher for FlexSure OBT than for Hemoccult SENSA (P < 0.001 and P = 0.016, respectively). Combining the positive results from both faecal occult blood tests did not improve the accuracy. CONCLUSION: The positive predictive value of the immunochemical faecal occult blood test for the detection of significant colorectal neoplasia was 29% better than that of the sensitive guaiac-based test. This may relate to the Chinese diet and requires further study. The poor specificity of the sensitive guaiac-based test, without dietary restriction, makes it less useful for colorectal cancer screening in a Chinese population.

Adult↗
PubMed2003

Lansoprazole reduces ulcer relapse after eradication of Helicobacter pylori in nonsteroidal anti-inflammatory drug users--a randomized trial.

AIM: To study whether prophylaxis with lansoprazole could prevent relapse of ulcers after eradication of Helicobacter pylori in patients with NSAID-related peptic ulcers. METHODS: Patients who presented with peptic ulcers and were found to be infected with H. pylori while receiving NSAIDs were recruited into the study. They received, twice daily, lansoprazole 30 mg, amoxicillin 1 g and clarithromycin 500 mg for 1 week, followed by lansoprazole 30 mg daily for 4 weeks. Patients with healed ulcers and H. pylori eradicated were given naproxen 750 mg daily, and randomly assigned to receive lansoprazole 30 mg daily or no treatment for 8 weeks. The primary endpoint was the cumulative recurrence of symptomatic and complicated ulcers. RESULTS: At the end of the 8-week treatment period, significantly fewer patients (1/22, 4.5%, 95% confidence interval [CI] 0-23) in the lansoprazole group compared with the group that received H. pylori eradication alone (9/21, 42.9%, 95% CI 22-66) developed recurrence of symptomatic and complicated ulcers (log rank test P=0.0025). CONCLUSIONS: Lansoprazole significantly reduced the cumulative relapse of symptomatic and complicated ulcers in patients requiring NSAIDs after eradication of H. pylori.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

Prevalence, clinical spectrum and health care utilization of gastro-oesophageal reflux disease in a Chinese population: a population-based study.

BACKGROUND: Population-based data on gastro-oesophageal reflux disease in Chinese are lacking. The prevalence, clinical spectrum and health care-seeking behaviour of subjects with gastro-oesophageal reflux disease were studied. METHODS: Ethnic Chinese (3605) were invited to participate in a telephone survey using a validated gastro-oesophageal reflux disease questionnaire and the Hospital Anxiety and Depression Scale. RESULTS: A total of 2209 subjects (58% female; mean age, 40.3 years) completed the interview. The annual, monthly and weekly prevalence rates of gastro-oesophageal reflux disease were 29.8%, 8.9% and 2.5%, respectively. Gastro-oesophageal reflux disease symptoms were associated with non-cardiac chest pain [odds ratio (OR), 2.3; 95% confidence interval (95% CI), 1.7-3.1], dyspepsia (OR, 1.9; 95% CI, 1.4-2.5), globus (OR, 1.8; 95% CI, 1.2-2.7), acid feeling in the stomach (OR, 5.8; 95% CI, 4.5-7.5) and the use of non-steroidal anti-inflammatory drugs (OR, 2.3; 95% CI, 1.5-3.6), but not with dysphagia, bronchitis, asthma, hoarseness and pneumonia. Patients with gastro-oesophageal reflux disease had a significantly higher anxiety and depression score and required more days off work when compared with subjects without. The frequency of heartburn (P = 0.032), female gender (P < 0.001), degree of depression (P = 0.004) and social morbidity (P < 0.001) were independent factors associated with health care-seeking behaviour. CONCLUSION: The prevalence of gastro-oesophageal reflux disease was lower than that in Western populations, but carried a significant socio-economic burden in the studied Chinese population. The frequency of heartburn, female gender and psychosocial factors were associated with health care utilization in gastro-oesophageal reflux disease.

Adult↗
PubMed2003

A validated symptoms questionnaire (Chinese GERDQ) for the diagnosis of gastro-oesophageal reflux disease in the Chinese population.

BACKGROUND AND AIMS: To develop a validated gastro-oesophageal disease (GERD) symptom questionnaire for the Chinese population. METHODS: One hundred Chinese patients with GERD and 101 healthy Chinese controls were presented with a 20-item GERD questionnaire in the Chinese language (Chinese GERDQ). Quality of life in GERD patients was assessed by SF-36. A standard dose of proton pump inhibitors for 4 weeks was prescribed to 35 patients with newly diagnosed GERD. The Chinese GERDQ was performed before, 4 weeks and 8 weeks after treatment. Concept, content, construct, discriminant validity and reliability of the questionnaire were assessed. RESULTS: Seven items were selected by logistic regression to account for most of the differences between controls and GERD patients with a good reproducibility and internal consistency. A cut-off score of equal or greater than 12 was determined to discriminate between controls and GERD patients with a sensitivity of 82% and a specificity of 84%. The Chinese GERDQ correlated negatively with five domains of the SF-36 and discriminated between GERD patients who reported symptomatic improvement during proton pump inhibitor treatment and symptoms deterioration upon withdrawal of proton pump inhibitor treatment. CONCLUSIONS: The Chinese GERDQ could be used in epidemiological studies to assess the frequency and severity of GERD in patient populations and in interventional studies of GERD.

China↗
PubMed2003

Randomized controlled study of rabeprazole, levofloxacin and rifabutin triple therapy vs. quadruple therapy as second-line treatment for Helicobacter pylori infection.

AIM: To test the efficacy of rabeprazole, levofloxacin and rifabutin triple therapy vs. quadruple therapy for the second-line treatment of Helicobacter pylori infection. METHODS: One hundred and nine patients who had failed previous H. pylori eradication were randomized to receive: (i) rabeprazole, 20 mg b.d., rifabutin, 300 mg once daily, and levofloxacin, 500 mg once daily, for 7 days (triple therapy); or (ii) rabeprazole, 20 mg b.d., metronidazole, 400 mg t.d.s., bismuth subcitrate, 120 mg q.d.s., and tetracycline, 500 mg q.d.s., for 7 days (quadruple therapy). Endoscopy and culture were performed before treatment. RESULTS: The clarithromycin (79% vs. 21%, P < 0.001) and metronidazole (89% vs. 40%, P < 0.001) resistance rates were significantly higher in patients with previous exposure than in those with no previous exposure. The intention-to-treat and per protocol eradication rates were 91%/91% for the triple therapy group and 91%/92% for the quadruple therapy group. For patients with double resistance to metronidazole and clarithromycin, the eradication rates were 85% (17/20) in the triple therapy group and 87% (13/15) in the quadruple therapy group. Compliance was greater than 95% for both regimens. CONCLUSION: Rabeprazole, levofloxacin and rifabutin-based triple therapy and quadruple therapy were equally effective as second-line treatments for H. pylori infection.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

A rapid-release 50-mg tablet-based 13C-urea breath test for the diagnosis of Helicobacter pylori infection.

BACKGROUND: Recently, a rapid-release 100-mg 13C-urea tablet with citrate supplement (Diabact UBT) showed excellent performance in a European population. AIM: To investigate the accuracy of a 50-mg tablet-based 13C-urea breath test protocol. METHODS: : Consecutive dyspeptic patients referred for upper endoscopy were recruited. 13C-Urea breath test was performed using a 50-mg 13C-urea tablet (Diabact UBT) and compared with the gold standard (rapid urease test and histology). Baseline, 10-min, 20-min and 30-min breath samples were collected in all cases. The cut-off values at each measurement interval were determined by three standard deviations above the mean excess delta 13CO2 excretion of Helicobacter pylori-negative patients. RESULTS: Two hundred patients (150 before therapy and 50 after therapy) were available for analysis, with a mean age of 48.4 years, and 99 patients (50%) were H. pylori positive. The sensitivity and specificity of the 50-mg tablet-based 13C-urea breath test at 10 min, 20 min and 30 min were 100% and 98%, 100% and 100%, and 100% and 98%, respectively. CONCLUSION: A 20-min, 50-mg tablet-based 13C-urea breath test (Diabact UBT) protocol is highly accurate for the diagnosis of H. pylori infection.

Adolescent↗
PubMed2003

Symptomatic response to lansoprazole predicts abnormal acid reflux in endoscopy-negative patients with non-cardiac chest pain.

AIM: To determine whether symptomatic response to lansoprazole predicts abnormal acid reflux in endoscopy-negative patients with non-cardiac chest pain. METHODS: Patients who complained of chest pain, but had normal coronary angiography, were asked to undergo upper endoscopy. Those without gastric and oesophageal lesions were recruited for 24-h ambulatory oesophageal pH monitoring, and were randomly given lansoprazole 30 mg or placebo, both daily for 4 weeks. Chest pain symptoms were recorded before and 1 month after treatment on a locally validated questionnaire. The symptom score was calculated by multiplying the severity and frequency of the symptom, and symptom improvement was defined as > 50% reduction in symptom score. RESULTS: Overall, 68 patients, 36 on lansoprazole and 32 on placebo, completed the trial. The symptom score was reduced significantly in both groups (P < 0.001). In the lansoprazole group, more patients with than without abnormal reflux showed symptom improvement (92% vs. 33%; odds ratio = 22; 95% confidence interval, 2.3-201.8; chi2 = 10.9; P = 0.001), giving a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 92%, 67%, 58%, 94% and 75%, respectively. In the placebo group, the rates of symptom improvement were similar between those with and without abnormal reflux (33% vs. 35%, P = N.S.). CONCLUSIONS: Treatment with lansoprazole is a useful test in diagnosing endoscopy-negative gastro-oesophageal reflux disease in Chinese patients with non-cardiac chest pain.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

A prospective comparison of performance of biopsy forceps used in single passage with multiple bites during upper endoscopy.

BACKGROUND AND STUDY AIMS: A single biopsy is usually obtained for each passage of a biopsy forceps. It was hypothesized that multiple bites per passage might improve the quantity and quality of tissue obtained, without significant artifacts. This hypothesis was tested in a prospective, pathologist-blinded study using different forceps. PATIENTS AND METHODS: Forty consecutive patients who underwent elective upper endoscopy were included. Five different forceps were used in six different ways, varying in the number of bites taken per passage. Two pathologists, who were blinded to the type of biopsy forceps used, evaluated the specimens according to the parameters of maximum weight (mg), size of largest fragment (mm), depth, squash artifact, adequacy, and overall rating. RESULTS: A total of 240 biopsy specimens were obtained. The Microvasive Multibite and Megabite forceps obtained specimens with the maximum weight (P<0.05) and the largest size (P<0.05), respectively. Alligator forceps were able to obtain specimens significantly larger in size than the oval-shaped forceps (P<0.05). The Olympus FB-24K forceps performed best in both the adequacy score and the overall rating score (P<0.05). CONCLUSIONS: Forceps with a needle, or the Multibite forceps, allow more biopsies to be taken per passage and improve the quality of tissues obtained. "Needleless" forceps can be used to obtain two samples per passage through the endoscope that are as good as when only one sample is collected. This approach can save time, and causes no significant damage to the biopsy specimens.

Adolescent↗
PubMed2003

Aspirin inhibits the growth of Helicobacter pylori and enhances its susceptibility to antimicrobial agents.

BACKGROUND AND AIM: The role of Helicobacter pylori and aspirin in peptic ulcer formation and recurrence remains an important clinical topic. The interaction between aspirin and H pylori in vitro is also not clear. We investigated the effect of aspirin on the growth of H pylori and on the susceptibility of H pylori to antimicrobials. METHODS: Time killing studies of H pylori were performed with different concentrations of aspirin and salicylate. Growth of bacteria was assessed spectrophotometrically and by viable colony count. The effects of aspirin on the efficiency of colony formation and on metronidazole induced mutation to rifampicin resistance in H pylori were determined. Minimal inhibitory concentrations (MICs) of aspirin and metronidazole were tested by the standard agar dilution method. MICs of amoxycillin and clarithromycin were determined by the E test method. RESULTS: Aspirin and salicylate inhibited the growth of H pylori in a dose dependent manner and bactericidal activity was due to cell lysis. Aspirin 400 micro g/ml caused a 2 logs decrease in colony forming units/ml at 48 hours, and suppressed the normal ability of metronidazole to induce new mutations to rifampicin. The IC(90) of aspirin was 512 micro g/ml. Increased susceptibility of amoxycillin, clarithromycin, and metronidazole to H pylori was observed at 1 mM (180 micro g/ml) aspirin. CONCLUSIONS: Aspirin inhibited the growth of H pylori, suppressed the mutagenic effect of metronidazole, and enhanced the susceptibility of H pylori to antimicrobial agents. This mechanism is important in future drug development for effective clearing and overcoming resistance.

Amoxicillin↗
PubMed2002

Optimal serological tests for the detection of Helicobacter pylori infection in the Chinese population.

BACKGROUND: Numerous serological tests for the detection of Helicobacter pylori infection have been developed. However, many perform poorly when evaluated in the Chinese population. AIM: To search for optimal serological tests for the detection of H. pylori infection in Chinese patients. METHODS: Consecutive dyspeptic patients referred for upper endoscopy were recruited. During endoscopy, gastric biopsies were taken for the CLOtest and histological examination. Patients were then given a 13C-urea breath test. Sera were used to test for H. pylori infection, employing three commercial enzyme-linked immunosorbent assay kits (pylori DTect, HP IgG and GAP IgG). Results were compared with the gold standard defined by the CLOtest, histology and 13C-urea breath test. RESULTS: Among the 142 patients (47 male, 95 female; mean age, 49 years) recruited, 81 (57%) were H. pylori-positive, 57 (40%) were H. pylori-negative and four (3%) were defined to be indeterminate. Using a self-defined cut-off value after calculation, the best accuracies for the pylori DTect, HP IgG and GAP IgG tests were 97%, 91% and 80%, respectively. CONCLUSIONS: The pylori DTect test is an optimal serological test for the detection of H. pylori infection in Hong Kong Chinese patients. The HP IgG test may be used as an alternative.

Breath Tests↗
PubMed2002

One-week omeprazole, furazolidone and amoxicillin rescue therapy after failure of Helicobacter pylori eradication with standard triple therapies.

AIM: To test the efficacy of omeprazole, furazolidone and amoxicillin triple therapy for the treatment of Helicobacter pylori infection after failure of standard first-line therapy recommended by the Asia-Pacific Consensus on the management of H. pylori infection. METHODS: Patients with failed H. pylori eradication received omeprazole, 20 mg, furazolidone, 100 mg, and amoxicillin, 1 g, all twice daily for 1 week. Endoscopy (CLO test, histology and culture) was performed before treatment. Post-treatment H. pylori status was determined by 13C-urea breath test 6 weeks later. RESULTS: Fifty patients were recruited. Resistance to metronidazole, clarithromycin and both drugs was in the range of 50-64%, 60-75% and 40-50%, respectively, after failure of first-line therapy. Amoxicillin resistance was not found. The intention-to-treat and per protocol H. pylori eradication rates were 52% and 53%, respectively. Patients with double resistance to metronidazole and clarithromycin showed the lowest eradication rate (38%), which was significantly lower than that of patients with sensitive strains (88%). Side-effects were minimal and compliance was excellent (98%). CONCLUSIONS: One-week omeprazole, furazolidone and amoxicillin rescue therapy achieved a high eradication rate in strains sensitive to metronidazole and clarithromycin. This is a cheap and safe rescue regimen when guided by pre-treatment sensitivity testing.

Adult↗
PubMed2002

An evaluation of a rapid urine test for the diagnosis of Helicobacter pylori infection in the Chinese population.

BACKGROUND: A new rapid urine test was developed to detect anti-Helicobacter pylori antibody in urine using the principle of immunochromatography. The accuracy of this test in the Chinese population remains to be defined. AIM: To evaluate a new rapid urine test for the diagnosis of H. pylori infection in the Chinese population. METHODS: Eligible patients without previous treatment of H. pylori were recruited. In-house rapid urease test and histology were used as the gold standard. The rapid urine test (RAPIRUN H. pylori antibody) was performed and the results were compared with the gold standard. RESULTS: One hundred and twenty-three patients were eligible for analysis and 61 (50%) were H. pylori positive by the gold standard. The rapid urine test showed a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 96.7%, 95.2%, 95.2%, 96.7% and 95.9%, respectively. Results were obtained within 20 min and no special laboratory support was required. CONCLUSIONS: The rapid urine test by immunochromatography is highly accurate for the diagnosis of H. pylori infection in untreated Chinese patients.

Adolescent↗
PubMed2002

Sequential intravenous/oral antibiotic vs. continuous intravenous antibiotic in the treatment of pyogenic liver abscess.

AIM: Pyogenic liver abscesses result in substantial morbidity and mortality. Antimicrobial regimens using sequential intravenous/oral therapy may reduce the length of hospital stay. In this retrospective analysis, the efficacy of continuous intravenous antibiotic therapy (group I) vs. sequential intravenous/oral antibiotic therapy (group II) was studied in patients with pyogenic liver abscess. METHODS: One hundred and twelve consecutive patients (55 in group I and 57 in group II) with pyogenic liver abscess were analysed. Clinical response, length of hospital stay and relapse rates were examined. RESULTS: Group II had a significantly shorter duration of intravenous antibiotic treatment (3.2 weeks vs. 5.9 weeks, P < 0.01) and a shorter length of hospital stay (28 days vs. 42 days, P < 0.01) when compared to group I. Oral antibiotics were prescribed for a median duration of 2.9 weeks in group II after discharge. No relapse occurred within 6 weeks after the completion of treatment in both groups. The cost of therapy was significantly lower in group II than in group I by 33%. CONCLUSIONS: A sequential intravenous/oral antibiotic regime is a safe and effective treatment for pyogenic liver abscess. This reduces the cost of therapy and the length of hospital stay.

Administration, Oral↗