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Biomedical subjects

K C Lai

Publications and source records attributed to K C Lai.

At least 73 records · Page 4Linked to original sources
PubMed2000

Evaluation of a new referral system for the management of dyspepsia in Hong Kong: role of open-access upper endoscopy.

BACKGROUND: In the management of dyspepsia, upper endoscopy is an important component. In our locality, patients requiring upper endoscopy are conventionally referred to specialist clinics by family physicians. We have introduced the first open-access upper endoscopy service in Hong Kong, which has allowed family physicians to arrange endoscopy without prior specialist consultation. A study on the outcome of open-access upper endoscopy in contrast with the conventional referral system was conducted. METHODS: For patients presenting with dyspepsia, family physicians in our region were given the option to arrange upper endoscopy directly with our Medical Endoscopy Unit in addition to the conventional referral to specialist clinics. The results were compared with those from the specialist clinic. A detailed prospective follow up was performed from June to September 1997 to evaluate the outcome and impact of open-access upper endoscopy. RESULTS: From November 1996 to September 1999, 978 referrals for open-access upper endoscopy were received. The service significantly reduced the waiting time for the procedure by 16 weeks. Open-access upper endoscopy had similar detection rates for peptic ulcers and cancers compared with referrals from specialist clinics. Seventy-five percent of patients did not require further consultation with their family physicians within 2 months after endoscopy. It is a safe and effective procedure in establishing a definitive diagnosis. All family physicians were satisfied with the open-access upper endoscopy service. CONCLUSIONS: This is the first Asian report on this service. Open-access upper endoscopy reduced waiting time from the patient perspective, decreased subsequent consultations with family physicians and reduced referral to specialist clinics as well as increased patient and doctor satisfaction. Both referral systems for endoscopy were similar in terms of the diagnostic yield.

Ambulatory Care Facilities↗
PubMed1999

Differential apoptosis by indomethacin in gastric epithelial cells through the constitutive expression of wild-type p53 and/or up-regulation of c-myc.

Nonsteroidal anti-inflammatory drug (NSAID)-induced apoptosis is considered to be an important mechanism in the antineoplastic effects and damage produced by the drugs in the gastrointestinal tract. In this study, two different gastric cancer cell lines, MKN28 (mutant-type p53) and AGS (wild-type p53), were compared as to growth inhibition, apoptosis, and cell cycle and apoptosis-related gene expression in response to indomethacin treatment. Cell growth was measured by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide) assay. Apoptosis was characterized by acridine orange staining and DNA fragmentation, and cell cycle kinetics by flow cytometry. The mRNA and protein levels of p53, p21waf1/cip1, and c-myc were determined by Northern and Western blotting. The results showed that indomethacin initiated growth inhibition and apoptosis in both cell lines without cell cycle shifting. AGS cells were more sensitive to growth inhibitory activity and apoptosis of indomethacin than MKN28 cells. In MKN28 cells, the levels of p53, p21waf1/cip1, and c-myc mRNA remained unchanged over the 24-hr treatment with indomethacin, but the p53 protein level was elevated after 4 hr. There was no change in the p21waf1/cip1 and c-myc protein levels in the MKN28 cells. In AGS cells, a progressive increase in c-myc mRNA and protein levels was noted, while p53 and p21waf1/cip1 remained unchanged. It can be concluded that wild-type p53 and/or up-regulation of c-myc is associated with indomethacin-mediated differential apoptosis in gastric epithelial cells.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Pharmacological inhibition of protein kinase C activity could induce apoptosis in gastric cancer cells by differential regulation of apoptosis-related genes.

The protein kinase C (PKC) signaling pathway plays a key role in tumor cell proliferation, differentiation, and apoptosis. Gastric cancer usually possesses a higher level of PKC activity than normal tissue. We evaluated inhibition of PKC activity in apoptosis induction of gastric cancer cells and the expression profile of apoptosis-related genes. Gastric cancer cells (AGS) were incubated with two highly specific PKC inhibitors (RO-31-8220 and chelerythrine). Cell viability and cell cycle were determined by methyl-tetrazolium (MTT) assay and flow cytometry, respectively. Apoptosis was characterized by acridine orange staining, DNA gel electrophoresis, and flow cytometry. The expression of p53, p21(waf/cip1), c-myc, bcl-2, and bax was determined by western blot. The results showed that both PKC inhibitors hindered cell growth, arrested cells at G0/G1 phase and induced apoptosis. The protein level of p53, p21(waf/cip1), c-myc, and bax was elevated while bcl-2 kept unchanged following drug exposure. In conclusion, PKC inhibitors suppress growth of gastric cancer cells through apoptosis induction and cell cycle quiescence, which may be regulated by differential expression of apoptosis-related genes.

Adenocarcinoma↗
PubMed1999

Non-steroidal anti-inflammatory drug-induced apoptosis in gastric cancer cells is blocked by protein kinase C activation through inhibition of c-myc.

Apoptosis plays a major role in gastrointestinal epithelial cell turnover, ulcerogenesis and tumorigenesis. We have examined apoptosis induction by non-steroidal anti-inflammatory drugs (NSAIDs) in human gastric (AGS) cancer cells and the role of protein kinase C (PKC) and apoptosis-related oncogenes. After treatment with aspirin or indomethacin, cell growth was quantified by MTT assay, and apoptosis was determined by acridine orange staining, DNA fragmentation and flow cytometry. The mRNA and protein of p53, p21waf1/cip1 and c-myc was detected by Northern and Western blotting respectively. The influence of PKC on indomethacin-induced apoptosis was determined by co-incubation of 12-O-tetradecanoylphorbol 13-acetate (TPA). The role of c-myc was determined using its antisense oligonucleotides. The results showed that both aspirin and indomethacin inhibited cell growth and induced apoptosis of AGS cells in a dose- and time-dependent manner, without altering the cell cycle. Indomethacin increased c-myc mRNA and protein, whereas p53 and p21wafl/cip1 were unchanged. Down-regulation of c-myc by its antisense oligonucleotides reduced apoptosis induction by indomethacin. TPA could inhibit indomethacin-induced apoptosis and accumulate cells in G2/M. Overexpression of c-myc was inhibited by TPA and p21waf1/cip1 mRNA increased. In conclusion, NSAIDs induce apoptosis in gastric cancer cells which may be mediated by up-regulation of c-myc proto-oncogene. PKC activation can abrogate the effects of NSAIDs by decreasing c-myc expression.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Triple therapy for Helicobacter pylori eradication is more effective than long-term maintenance antisecretory treatment in the prevention of recurrence of duodenal ulcer: a prospective long-term follow-up study.

BACKGROUND: The effectiveness of Helicobacter pylori eradication treatment and long term acid suppression maintenance in the natural course of duodenal ulcer has not been directly compared. AIM: To compare in a prospective randomized study the effectiveness of H. pylori eradication on the prevention of recurrence of duodenal ulcer with long-term maintenance acid suppression therapy. METHODS: One hundred and fourteen duodenal ulcer patients were randomized to the treatment over a 12-month period. Fifty-seven of them received triple therapy consisting of 1 g sucralfate q.d.s. for 28 days, 300 mg metronidazole q.d.s. for 14 days and 250 mg clarithromycin q.d.s. for 14 days. Another 57 received 20 mg omeprazole q.d.s. for 12 months. An upper endoscopy was performed before treatment, at 6 weeks, and 2, 6 and 12 months after the first endoscopy. Side-effects were self-recorded and clinical follow-ups were arranged for up to 4.25 years. RESULTS: The ulcer healing rate was 90.2% (95% confidence interval (95% CI): 79-97%) in the omeprazole group at 6 weeks as compared to 83.3% (95% CI: 70-93%) in the triple therapy group (P = 0.38). There was a higher success rate of pain control in the omeprazole group. Side-effects were more frequently reported and compliance was poorer in the triple therapy group during the first 4 weeks. During follow-up, more relapses were seen in the omeprazole group (9.8%, 95% CI: 3-21%) than the triple therapy group (4.2%, 95% CI: 1-13%) at 1 year (P = 0.44). All relapses were due to the persistence of H. pylori infection. At the 1 year follow-up, none of the patients who were H. pylori negative had an endoscopic relapse compared to 7 out of 56 patients who remained H. pylori positive (12.5%, 95% CI: 5-24%, P = 0.018). After a mean follow-up of 4.07 years, none of those who remained H. pylori negative had an ulcer relapse while the 11 out of 41 who remained H. pylori positive had an ulcer relapse (26.8%, 95% CI 14-43, P = 0. 0005). CONCLUSIONS: Both regimens were highly effective in healing ulcers. The eradication of H. pylori infection was associated with more side-effects and poor compliance but was more effective than the maintenance therapy in reducing the recurrence of duodenal ulcers. For the prevention of ulcer recurrence, testing of H. pylori status after triple therapy is more important than maintenance therapy.

Adult↗
PubMed1999

Seroprevalence of cytotoxin-associated gene A positive Helicobacter pylori strains in Changle, an area with very high prevalence of gastric cancer in south China.

BACKGROUND: Helicobacter pylori, especially the CagA-positive strains, are closely associated with peptic ulcers and gastric cancers. We performed a large scale gastric cancer screening project and examined the prevalence of H. pylori and CagA-positive strains in Changle, China, an area with one of the World's highest gastric cancer mortality. We also compared the prevalence with that in Hong Kong which has one-tenth of the gastric cancer mortality of that in Changle. METHODS: A total of 2424 subjects in Changle and 523 subjects in Hong Kong had endoscopic examination and venesection. Sera were tested for anti-H. pylori antibody and anti-CagA antibody and correlated with endoscopic findings. RESULTS: In Changle, 80. 9% of the subjects were H. pylori carriers. Out of 551 carriers, 408 (74%) were positive for anti-CagA antibody. A total of 76% and 87% of the asymptomatic and gastric cancer patients were positive for anti-CagA antibody, respectively (P > 0.05). Compared to Hong Kong, there was a significantly (P < 0.0001) higher prevalence of CagA-positive strains in asymptomatic subjects in Changle (76%) than in Hong Kong (28%), but not in peptic ulcers or gastric cancers. CONCLUSIONS: Subjects in Changle had a high prevalence of H. pylori infection and a high prevalence of the CagA-positive strains. The contrast in the prevalence of CagA-positive strains, in asymptomatic subjects in two areas with differing gastric cancer mortality, supports the pathogenic role of CagA-positive strains in gastric carcinogenesis.

Adolescent↗
PubMed1999

Differential Helicobacter pylori infection rates in two contrasting gastric cancer risk regions of South China. China Gastric Cancer Study Group.

BACKGROUND: Carriers of Helicobacter pylori are believed to have a three- to six-fold increased risk of developing gastric cancer. We have recently conducted a simultaneous cross-sectional population study on the prevalence of H. pylori infection in a cohort of asymptomatic adult volunteers in two contrasting gastric cancer risk regions of South China, Hong Kong and Changle of Fujian. Their mean annual gastric cancer mortality has been approximately 7.5 and 75/100 000 population, respectively, since the beginning of the last decade. The aim of this study was to evaluate if H. pylori prevalence bears any relationship to gastric cancer mortality rates in these two southern regions of China. METHODS: Sera were obtained from 397 volunteers in Hong Kong. They were tested for anti-H.pylori immunoglobulin (Ig) G antibody by using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Volunteers of Changle (1456) had upper endoscopy examination and were also tested for anti-H. pylori IgG antibody by the same ELISA method. RESULTS: The overall H. pylori infection prevalence was significantly higher in Changle (80.4%) than in Hong Kong (58.4%; P< 0.01). The high prevalence is associated with more atrophic gastritis. The overall risk of gastric cancer in people of Changle is approximately five-fold that of Hong Kong (adjusted odds ratio 4.9, 95% CI 2.5-9.8). CONCLUSIONS: It is concluded that the prevalence of H. pylori infection rates bear a direct relationship to gastric cancer mortality rates in these two southern regions of China. Thus, H. pylori most likely plays a significant aetiopathogenetic role in gastric carcinogenesis in subjects living in Changle.

Adult↗
PubMed1999

The need for Helicobacter pylori eradication therapy in patients with peptic ulcer bleeding.

Peptic ulcer bleeding is an important complication of peptic ulceration. The condition carries significant morbidity and mortality despite advances in both endoscopic intervention techniques and pharmacological treatment. About one third of patients have a recurrence of bleeding within a few years of discharge. Before Helicobacter pylori was discovered, most of these patients were given maintenance therapy with antisecretory drugs or surgery to prevent a recurrence of the bleeding. Since the eradication of Helicobacter pylori reduces the recurrence of uncomplicated peptic ulcers, its eradication should also reduce peptic ulcer complications. The aim of this review is to discuss the value of eradicating Helicobacter pylori as part of the long-term management of bleeding peptic ulcers.

Journal Article↗
PubMed1998

Nonsteroidal antiinflammatory drugs could reverse Helicobacter pylori-induced apoptosis and proliferation in gastric epithelial cells.

It remains controversial whether the harmful effects of Helicobacter pylori (Hp) and nonsteroidal antiinflammatory drugs (NSAIDs) are additive. We studied the effects of Hp (virulent and nonvirulent strains) and NSAIDs, alone or in combination, on apoptosis and proliferation of gastric epithelial cells in nonulcer dyspepsia (NUD) patients. Forty-four (25 Hp-positive and 19 Hp-negative) consecutive Chinese NUD patients with rheumatoid arthritis who had taken continuously NSAIDs for more than three months were recruited for this study. Another 41 (20 Hp-positive and 21 Hp-negative) NUD patients not on any NSAIDs were included as controls. All patients underwent a gastroscopy examination and gastric biopsies. Hp infection was confirmed by CLOtest, anti-Hp ELISA, and [13C]urea breath test. The CagA status was determined by the anti-CagA antibody assay. The degree of gastritis, apoptosis, and proliferation indices were determined with H&E staining, terminal uridine deoxynucleotidyl nick end-labeling (TUNEL), and proliferating cell nuclear antigen (PCNA) immunostaining methods, respectively. A significantly higher apoptosis was observed in subjects who had Hp infection or had been consuming NSAIDs when compared with the controls. Unlike NSAID-treated subjects, patients with Hp infection were shown to have significantly enhanced cell proliferation. However, the increased apoptosis and proliferation in Hp-positive subjects were reversed by also taking NSAIDs. No correlation was found between apoptosis and proliferation in all the study groups. There was no association found between CagA expression or degree of gastritis with cell proliferation or apoptosis. It was demonstrated at the cellular level that NSAIDs could abrogate apoptosis or proliferation effects induced by Hp. Furthermore, the latter effects appeared not to be influenced by the virulent nature of the Hp strains.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1998

Effect of simethicone on the accuracy of the rapid urease test.

OBJECTIVE: Simethicone, which is a principal ingredient in the defoaming agent used during gastroscopy, can inhibit the growth of Helicobacter pylori (MIC, 64-128 mg/l). This prospective study was designed to evaluate the in vivo and in vitro effects of simethicone on the accuracy of the rapid urease test (RUT). METHODS: In the in vivo study, three sets of gastric biopsies (two from the antrum, and one from the corpus) were taken from 75 patients. The first set was examined histologically, and the second set was used for the RUT (pre-simethicone RUT). Then, 25 ml simethicone (1200 mg/l) was introduced into the stomach for a contact time of 1 min. A third set of gastric biopsies was taken for the RUT (post-simethicone RUT). In the in vitro clinical study, 41 patients were recruited. The first set of gastric biopsies was used for the RUT (pre-incubation RUT). The second set was incubated in 1 ml of simethicone for 5 min before being used for the RUT (post-incubation RUT). In the spectrophotometric study, urease activity before and after incubation in simethicone for 5 min was quantified in 12 patients by measuring the absorbance at 560 nm. RESULTS: Reading at 15 min, the concordance rate between the pre-simethicone and post-simethicone RUT was 98%. In the in vitro clinical study, the concordance rate between the pre-incubation and post-incubation RUT was 97%. The spectophotometric study showed a significant reduction of 43% in urease activity after incubation in simethicone. CONCLUSION: The application of a defoaming agent containing simethicone does not affect the accuracy of the RUT. However, simethicone modestly suppresses urea hydrolysis.

Diagnostic Techniques, Digestive System↗
PubMed1997

A retrospective and prospective study on the safety of discharging selected patients with duodenal ulcer bleeding on the same day as endoscopy.

BACKGROUND: Low risk of rebleeding has been observed in patients with gastrointestinal bleeding due to peptic ulcer without high-risk stigmata of recent hemorrhage. We aimed to evaluate the safety and acceptability of an aggressive early discharge policy in those patients admitted with upper gastrointestinal bleeding due to duodenal ulcers without high-risk stigmata of recent hemorrhage. METHOD: Retrospective analysis was carried out in bleeding ulcer patients less than 60 years of age with stable vital signs and no stigmata or only flat spots on endoscopy. A prospective study was then performed that included only duodenal ulcer patients less than 60 years of age with stable vital signs, no concomitant serious medical illness, and no stigmata of recent hemorrhage. These patients were discharged on the same day that endoscopy was performed. RESULTS: During a period of 18 months, 72 patients satisfied the criteria in the retrospective study. The mean hospital stay was 1.4 days (range, 1 to 5). There were no episodes of rebleeding nor significant drops in hemoglobin level 2 weeks after discharge (10.8 gm/dL +/- 1.4 vs 11.0 gm/dL +/- 1.5). Seventy-five patients were recruited into the prospective study. None of them had rebleeding nor significant drops in hemoglobin 1 week after discharge (12.1 gm/dL +/- 1.8 vs 11.7 gm/dL +/- 2.5). CONCLUSION: We conclude that patients with gastrointestinal bleeding who have clean-based duodenal ulcers and are stable on admission can be safely discharged on the same day as endoscopy.

Adolescent↗
PubMed1997

Does treatment of Helicobacter pylori with antibiotics alone heal duodenal ulcer? A randomised double blind placebo controlled study.

BACKGROUND: Treatment of Helicobacter pylori infection prevents duodenal ulcer relapse. It has not been established if treatment of the infection heals duodenal ulcer. AIM: To test the hypothesis that treatment of the infection was associated with healing of duodenal ulcer. METHODS: A randomised, double blind placebo controlled trial was performed to study the efficacy of an antibiotic only regimen consisting of 300 mg metronidazole, 500 mg amoxycillin, and 250 mg clarithromycin, each given four times daily for two weeks, in the healing of duodenal ulcer as assessed by endoscopy. Symptoms were controlled with acetaminophen and antacids. RESULTS: Of 100 consecutive patients with endoscopically established duodenal ulcer, 97 with positive rapid urease test on antral biopsy specimens were admitted into the study and 81 completed the trial. Of these, 40 were randomised to receive antibiotics and 41 to receive placebo. Treatment with antibiotics resulted in 92.5% (95% confidence interval (95% CI) 84.3-100) healing at four weeks and 100% at eight and 12 weeks; the corresponding healing rates for placebo treatment were respectively, 36.6%, 61%, and 63.4% (95% CIs 21.8-51.3, 46.0-75.9, and 48.7-78.2 respectively). The differences between the two treatment groups were significant at p < 0.001 at each time point and by life table analysis. Clearance of H pylori as assessed by urease test on antral biopsy specimens at four weeks and eradication of the organism as determined by 13C-urea breath test at eight weeks were achieved in 85% and 62.5% of patients respectively. Duodenal ulcer healed at four weeks in 87.2% and 86.2% (95% CIs 76.7-97.7 and 73.7-98.8) of patients in whom H pylori clearance or eradication, was achieved, versus 42.9% and 51.9% (95% CIs 27.9-57.8 and 38.3-65.5; p < 0.001 and < 0.003 respectively) in whom these processes failed. Stepwise discriminant analysis on 32 clinical, personal, and endoscopic characteristics as well as H pylori clearance and eradication identified H pylori clearance as the most discriminative variable for the healing of duodenal ulcer at four weeks, followed by ulcer depth and eradication of the organism. CONCLUSIONS: Treatment with an antibiotic only regimen was effective for the healing of duodenal ulcer, and clearance as well as eradication of H pylori contributed significantly to the healing. The results constituted the strongest evidence to date that H pylori infection was aetiologically related to duodenal ulceration, and support the concept of treating duodenal ulcer associated with H pylori as an infection and relieving its symptoms with acid reducing agents such as antacids.

Adult↗
PubMed1996

Changes in cytosolic calcium concentrations and cell morphology in single platelets adhered to fibrinogen-coated surface under flow.

Changes in intracellular calcium concentration [Ca2+]i of fura-2-loaded human platelet during its adhesion to a fibrinogen-coated surface were studied, using a flow chamber mounted on an epifluorescence microscope equipped with digital-ratio imaging. Adherent platelets were individually mapped under a scanning electron microscope to establish the possible correlation between adhesion-associated shape alterations and [Ca2+]i changes. We found that 1) there was no immediate [Ca2+]i elevation on platelet adhesion; 2) [Ca2+]i changes varied drastically platelets with a lag time ranging 10 to 200 s, averaging about 1 minute; 3) the pattern of [Ca2+]i changes varied drastically among individual adherent platelets; 4) the degree of [Ca2+]i elevation appeared to correlate with the extent of morphology change, with the vast majority ( > 90%) of spread platelets showed detectable [Ca2+]i changes; 5) neither morphological nor [Ca2+]i changes correlated with the lag time; 6) platelets treated with dimethyl-BAPTA (15 mumol/L) underwent normal shape change without [Ca2+]i elevation; 7) cytochalasin D (10 mumol/L) inhibited both shape change and [Ca2+]i elevation; 8) colchicine (1 mmol/L) was ineffective in both regards. We conclude that although platelet adhesion-associated shape changes may be accompanied with heterogeneous [Ca2+]i changes that are microfilament-dependent, [Ca2+]i changes do not happen immediately after platelet-surface contact and they are not required for adherent platelets to undergo postcontact morphological changes.

Blood Platelets↗
PubMed1996

Clinical and histological features of gastric antral vascular ectasia: successful treatment with endoscopic laser therapy.

Gastric antral vascular ectasia is a rare but important cause of chronic gastrointestinal bleeding. We report five patients in whom endoscopic laser therapy successfully controlled repeated blood loss. The patients were elderly (age range: 61-84 years; mean age: 75 years) and three of them were female. Endoscopically, all patients presented with a characteristic antral appearance of either ecstatic vascular 'stripes' radiating out from the pylorus, or multiple cherry-red spots. In all patients, the gastric mucosal biopsy specimens showed dilatation of the capillaries with focal fibrin thrombi and fibromuscular hyperplasia. Marked improvement of both endoscopic and histological features was achieved with endoscopic laser treatment using Nd-YAG laser photocoagulation. Its importance lies in its recognition and successful treatment with endoscopic laser therapy, which offers an effective and relatively safe alternative to surgery, particularly in elderly patients.

Aged↗
PubMed1996

Abnormal gastro-oesophageal reflux in Chinese with atypical chest pain.

Although atypical chest pain has been well described in the Western population, its frequency in Chinese is unknown. Over a period of 42 months, we studied 521 Chinese patients with chest pain and identified 108 patients (20.7%) whose pain was not related to cardiac causes, as determined by exercise ECG or cardiac catheterization. Using 24 h ambulatory pH monitoring and baseline oesophageal manometry, 28.7, 19.4 and 5.6% of these patients were found to have abnormal reflux parameters, abnormal manometric findings or both, respectively. There were significantly more patients complaining of chest pain during the study in the gastro-oesophageal reflux disease (GERD) group than in the non-GERD group (16/31 vs 20/77; P < 0.001). The lower oesophageal sphincter pressure was lower in those with abnormal reflex parameters than in those with normal reflux parameters (12.7 +/- 5.4 vs 17.8 +/- 5.8 mmHg; P < 0.05). There was no significant difference in symptoms, such as heartburn (54.8 vs 42.9%), regurgitation (38.7 vs 35.1%) and dysphagia (19.4 vs 24.7%), among the two groups. Non-specific changes were the most frequent baseline motility pattern. In conclusion, atypical chest pain and gastro-oesophageal reflux disease are not uncommon in Chinese and this deserves special emphasis as the continuation of anti-anginal drugs may aggravate their condition.

Adolescent↗
PubMed1996

Prevalence of metronidazole resistant Helicobacter pylori strains among Chinese peptic ulcer disease patients and normal controls in Hong Kong.

BACKGROUND: A study was conducted to evaluate the prevalence of metronidazole resistant Helicobacter pylori strains among the Chinese in Hong Kong. The efficacy of the triple therapy that contains metronidazole as one of the anti-microbial agents in eradication of the metronidazole susceptible and the metronidazole resistant strains was also assessed. METHODS: Culture for H pylori was attempted from antral biopsy specimens of 70 peptic ulcer and 51 control subjects. Successfully cultured H pylori strains were tested for metronidazole susceptibility. Twenty six peptic ulcer disease subjects who had received a course of triple therapy were also reassessed four to six weeks later for successful eradication of H pylori infection. RESULTS AND CONCLUSIONS: H pylori was successfully cultured from antral biopsy specimens in 69 of 80 (86%) of the infected subjects. The overall metronidazole resistance rate was 53.5% (37 of 69). There was a significantly higher metronidazole resistance rate among H pylori isolates from the asymptomatic controls (20 of 25) than the peptic ulcer disease subjects (17 of 44) (p = 0.0007). Twenty three of 32 (73%) women and 14 of 37 (38%) men harboured the metronidazole resistant strains. There was no sex or age difference as far as the prevalence of metronidazole resistant strains were concerned within each study group. Pre-treatment metronidazole susceptible H pylori were significantly more likely to respond to the triple therapy used than those with the metronidazole resistant ones (14 of 15 v five of 10) (p = 0.021).

Anti-Ulcer Agents↗