SMRT sequencing revealed the diversity and characteristics of defective interfering RNAs in influenza A (H7N9) virus infection

Influenza defective interfering (DI) particles are replication-incompetent viruses carrying large internal deletion in the genome. The loss of essential genetic information causes abortive viral replication, which can be rescued by co-infection with a helper virus that possesses an intact genome. Despite reports of DI particles present in seasonal influenza A H1N1 infections, their existence in human infections by the avian influenza A viruses, such as H7N9, has not been studied. Here we report the ubiquitous presence of DI-RNAs in nasopharyngeal aspirates of H7N9-infected patients. Single Molecule Real Time (SMRT) sequencing was first applied and long-read sequencing analysis showed that a variety of H7N9 DI-RNA species were present in the patient samples and human bronchial epithelial cells. In several abundantly expressed DI-RNA species, long overlapping sequences have been identified around at the breakpoint region and the other side of deleted region. Influenza DI-RNA is known as a defective viral RNA with single large internal deletion. Beneficial to the long-read property of SMRT sequencing, double and triple internal deletions were identified in half of the DI-RNA species. In addition, we examined the expression of DI-RNAs in mice infected with sublethal dose of H7N9 virus at different time points. Interestingly, DI-RNAs were abundantly expressed as early as day 2 post-infection. Taken together, we reveal the diversity and characteristics of DI-RNAs found in H7N9-infected patients, cells and animals. Further investigations on this overwhelming generation of DI-RNA may provide important insights into the understanding of H7N9 viral replication and pathogenesis.

Inguinal Hernia Mimicking as a Spigelian Hernia

Inguinal hernia is a common surgical condition requiring surgical intervention. The usual clinical presentation is a supra-inguinal swelling with the neck just above and medial to pubic tubercle. We report a case of inguinal hernia in an old lady that presented as an abdominal wall swelling, clinically suggestive of a Spigelian hernia.

Bochdalek Hernia Presented as a ‘Pop’ Sound in an Adult

Bochdalek hernia is a congenital diaphragmatic hernia in which intra-abdominal organs protrude into the thoracic cavity through an opening in the diaphragm. It rarely occurs in adults. We report one such case in a 24-year-old lady who presented with a pop sound and acute onset of abdominal pain. Imaging investigation confirmed the diagnosis and laparoscopic repair was done. The importance of high clinical suspicion, consideration of Bochdalek hernia as a differential diagnosis of acute abdominal pain and the role of imaging for accurate diagnosis is emphasized.

Leukotriene signaling via ALOX5 and cysteinyl leukotriene receptor 1 is dispensable for in vitro growth of CD34+CD38- stem and progenitor cells in chronic myeloid leukemia

Tyrosine kinase inhibitors targeting the BCR-ABL oncoprotein in chronic myeloid leukemia (CML) are remarkably effective inducing deep molecular remission in most patients. However, they are less effective to eradicate the leukemic stem cells (LSC), resulting in disease persistence. Therefore, there is great need to develop novel therapeutic strategies to specifically target the LSC. In an experimental mouse CML model system, the leukotriene pathway, and specifically, the expression ALOX5, encoding 5-lipoxygenase (5-LO), has been reported as a critical regulator of the LSC. Based on these results, the 5-LO inhibitor zileuton has been introduced in clinical trials as a therapeutic option to target the LSC although its effect on primary human CML LSC has not been studied. We have here by using multiplex single cell PCR analyzed the expression of the mediators of the leukotriene pathway in bone marrow (BM) BCR-ABL⁺CD34⁺CD38^- cells at diagnosis, and found low or undetectable expression of ALOX5. In line with this, zileuton did not exert significant overall growth inhibition in the long-term culture-initiating cell (LTC-IC) and colony (CFU-C) assays of BM CD34⁺CD38^- cells from 7 CML patients. The majority of the single leukemic BCR-ABL⁺CD34⁺CD38^- cells expressed cysteinyl leukotriene receptors CYSLT1 and CYSLT2. However, montelukast, an inhibitor of CYSLT1, also failed to significantly suppress CFU-C and LTC-IC growth. These findings indicate that targeting ALOX5 or CYSLT1 signaling with leukotriene antagonists, introduced into the clinical practice primarily as prophylaxis and treatment for asthma, may not be a promising pharmacological strategy to eradicate persisting LSC in CML patients.

Managing malignant pleural effusion with an indwelling pleural catheter: factors associated with spontaneous pleurodesis

INTRODUCTION

Malignant pleural effusion can be recurrent despite active anti-cancer treatment. Significant malignant pleural effusion leads to debilitating dyspnoea and worsening quality of life in patients with advanced cancer. An indwelling pleural catheter offers a novel means to manage recurrent malignant pleural effusion and may remove the need for repeated thoracocentesis. Spontaneous pleurodesis is another unique advantage of indwelling pleural catheter placement but the factors associated with its occurrence are not clearly established. The aims of this study were to explore the safety of an indwelling pleural catheter in the management of symptomatic recurrent malignant pleural effusion, and to identify the factors associated with spontaneous pleurodesis.

METHODS

This case series with internal comparisons was conducted in the Division of Respiratory Medicine, Department of Medicine, Queen Mary Hospital, Hong Kong. All patients who underwent insertion of an indwelling pleural catheter from the initiation of such service from January 2010 to December 2014 were included for data analysis. Patients were monitored until December 2014, with the last catheter inserted in July 2014.

RESULTS

Between 2010 and 2014, a total of 23 indwelling pleural catheters were inserted in 22 consecutive patients with malignant pleural effusion, including 15 (65.2%) cases with malignant pleural effusion as a result of metastatic lung cancer. Ten (43.5%) cases achieved minimal output according to defined criteria, in five of whom the pleural catheter was removed without subsequent re-accumulation of effusion (ie spontaneous pleurodesis). Factors associated with minimal output were the absence of trapped lung (P=0.036), shorter time from first appearance of malignant pleural effusion to catheter insertion (P=0.017), and longer time from catheter insertion till patient's death or end of study (P=0.007).

CONCLUSIONS

An indwelling pleural catheter provides a safe means to manage symptomatic malignant pleural effusion. Potential clinical factors associated with minimal output were identified along with the occurrence of spontaneous pleurodesis, which is a unique advantage offered by indwelling pleural catheter.

Expression of integrin α2 receptor in human cord blood CD34+CD38-CD90+ stem cells engrafting long-term in NOD/SCID-IL2Rγ(c) null mice

Human hematopoietic stem cells reside in the CD34+CD38-CD90+ population in cord blood and bone marrow. However, this cell fraction is heterogeneous, and the phenotype of the rare primitive stem cells remains poorly defined. We here report that primitive cord blood CD34+CD38-CD90+ stem cells, with the ability to reconstitute NOD/SCID-IL2Rγ(c) null (NSG) mice long-term, at 24 weeks after transplantation, can be prospectively isolated at an increased purity by using integrin α2 receptor as an additional stem cell marker. Using a limiting dilution transplantation assay, we found a highly significant enrichment of multilineage reconstituting stem cells in the CD34+CD38-CD90+ cell fraction expressing the integrin α2 receptor, with a frequency of 1/29 cells, as compared to a frequency of 1/157 in the corresponding integrin α2- cells. In line with this, long-term reconstituting stem cells within the cord blood CD34+CD38- cell population were significantly enriched in the integrin α2+ fraction, while stem cells and progenitors reconstituting short-term, at 8-12 weeks, were heterogeneous in integrin α2 expression. Global gene expression profiling revealed that the lineage-marker negative (Lin-) CD34+CD38-CD90+CD45RA- integrin α2+ cell population was molecularly distinct from the integrin α2- cell population and the more mature Lin-CD34+CD38-CD90-CD45RA- cell population. Our findings identify integrin α2 as a novel stem cell marker, which improves prospective isolation of the primitive human hematopoietic stem cells within the CD34+CD38-CD90+ cell population for experimental and therapeutic stem cell applications.

Endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer: the first experience in Hong Kong

OBJECTIVE

To investigate the diagnostic performance and safety of endobronchial ultrasound-guided transbronchial needle aspiration in patients presenting with radiological features of lung cancer.

DESIGN

Prospective case series.

SETTING

University teaching hospital, Hong Kong.

PATIENTS

Consecutive patients with mediastinal or hilar abnormalities suspected of or confirmed as having lung cancer underwent endobronchial ultrasound-guided transbronchial needle aspiration and presented between August 2006 and December 2010.

MAIN OUTCOME MEASURES

Diagnostic performance (including sensitivity, specificity, negative predictive value and accuracy), procedural complications, and tissue adequacy for molecular profiling.

RESULTS

A total of 269 procedures were performed in 259 patients, with malignancy confirmed in 210 (81%) of them. In the whole cohort with confirmed or suspected lung cancer, the overall sensitivity, specificity, negative predictive value, and accuracy of endobronchial ultrasound-guided transbronchial needle aspiration were 87%, 100%, 74%, and 91%, respectively. Among 42 patients with tumour samples sent for mutation tests (epidermal growth factor receptor and/or anaplastic lymphoma kinase), 40 (95%) were found to be adequate. No complication or mortality ensued from these procedures.

CONCLUSION

Endobronchial ultrasound-guided transbronchial needle aspiration is highly effective in determining the diagnosis and lymph node staging in patients with lung cancer. In combination with its excellent safety profile, it should be considered a frontline diagnostic test for patients presenting with mediastinal abnormalities suspicious of lung cancer.

No association of alcohol dependence with HOMER 1 and 2 genetic variants

Several lines of evidence indicate that alterations of the central cortico-accumbens glutamate pathway are involved in the development and maintenance of alcohol- and substance-use disorders. The HOMER protein family is encoded by 3 genes HOMER (1-3) which are components of the excitatory postsynaptic density complex and function to modulate synaptic activity by the regulation of glutamate signaling. HOMER 1 and 2 have been reported to contribute to chronic alcohol-induced long-term neurochemical changes in the endogenous reward system. Data from animal models suggest a potential role of the Homer protein family in the development of alcohol and substance use. The aim of this study is to assess potential associations between HOMER 1 and 2 genetic variants in a larger sample of alcohol-dependent individuals and unrelated controls. Five genetic variants of HOMER 1 and 3 of HOMER 2 were genotyped in a multi-site sample of 1,923 German healthy controls and 2,039 alcohol-dependent subjects. Neither single SNP nor haplotype analysis could detect significant associations with alcohol dependence (AD) and related phenotypes. While most of the HOMER 1 and 2 SNPs are in low-to-moderate linkage disequilibrium, three major haplotypes of HOMER 1 and 4 haplotypes of HOMER 2 are present in the majority of alcohol-dependent and control subjects. In conclusion, our results suggest that single SNPs, respectively, haplotypes of the HOMER 1 and 2 genes are unlikely to play a major role in the pathophysiology of AD.

[Depressive disorders in dementia and mild cognitive impairments: is comorbidity a cause or a risk factor?]

Both depression and dementia occur by themselves or together in elderly subjects aged 65 and above. The aim of this review is to discuss several hypotheses which try to explain the frequent co-occurrence exceeding chance alone, based on a systematic literature search. A series of studies revealed potential biological similarities between both disorders which, however, were not found in all investigations. Lifetime history of depression can be considered as a distant risk factor for dementias. Depression occurs most frequently within one year before and after the onset of dementia, in which the association between both disorders is probably strongest. In a subgroup of subjects with more "cognitive reserve", depression was found to be a consequence of patient's realisation of beginning cognitive deficits. Several studies indicate that depression in Alzheimer and other dementia forms can be considered as a separate disease entity, as the clinical syndrome differs from depression in earlier periods of life. Studies on the therapy of depression in dementia have aroused increasing interest in recent years. Herewith, certain guidelines in the treatment of older patients with antidepressants must be followed.

Positive association between gastro-oesophageal reflux disease and irritable bowel syndrome in a Chinese population

BACKGROUND

Gastro-oesophageal reflux disease and irritable bowel syndrome are common diseases which may be related.

AIM

To examine the association between gastro-oesophageal reflux disease and irritable bowel syndrome in Chinese population in Hong Kong.

METHODS

Randomly selected ethnic Chinese were invited to participate in a telephone survey in 1996. Gastro-oesophageal reflux disease was defined as subjects having heartburn and/or acid regurgitation once weekly or more. Irritable bowel syndrome was diagnosed according to the Rome I criteria. The association between gastro-oesophageal reflux disease and irritable bowel syndrome was calculated using a statistical model which allows the odds ratio to be measured.

RESULTS

One thousand six hundred and forty-nine subjects completed the interview (response rate 62%). The population prevalence of gastro-oesophageal reflux disease and irritable bowel syndrome were 5% and 4%, respectively. Thirteen per cent of subjects with gastro-oesophageal reflux disease and 11% with irritable bowel syndrome suffered from both gastro-oesophageal reflux disease and irritable bowel syndrome. The OR of having gastro-oesophageal reflux disease and irritable bowel syndrome together was estimated to be 3 (95% CI: 1.05, 6.27) indicating a positive association between the two diseases. This association occurred predominantly in male subjects [OR = 9.3, (95% CI: 2.3, 26.2)] but not as strong in females [OR = 1.5, (95% CI: 0.3, 4.3)]. Younger subjects were statistically more prone to the two diseases.

CONCLUSIONS

There is a positive association between gastro-oesophageal reflux disease and irritable bowel syndrome, and their association occurs predominantly in male subjects.

Cyclin I and p53 are differentially expressed during the terminal differentiation of the postnatal mouse heart

In this study, we have used Ki-67 and MF20 mAb to determine how extensively cardiomyocytes proliferate in the postnatal mouse heart. It was established that the cardiomyocytes divided rapidly in 2-day-old hearts. However, at 13 days, the majority of cardiomyocytes had entered into terminal growth arrest and differentiation. We exploited this finding in order to identify proteins that were associated with cardiomyocyte growth and differentiation. The protein profiles of 2- and 13-day-old hearts were established by two-dimensional electrophoresis and compared. Seventeen protein spots were found to be differentially expressed at day 13. Eight of them were up-regulated while the remaining nine protein spots were down-regulated. We focused our attention on 2 of the proteins identified by MALDI-TOF MS, cyclin I and p53, because they are both believed to be involved in cell cycle regulation. Western blot analysis confirmed that both proteins were positively up-regulated in the 13-day-old postnatal heart. To determine directly whether these proteins were associated with cell proliferation, we examined their expression patterns in H9c2 cardiomyocytes maintained in vitro. We established that cyclin I expression was low during the growing phase of H9c2 culture and high during the growth arrest/differentiation phases. In contrast, p53 expression was unchanged during both phases. The various growth phases were confirmed by the presence of cyclin A and growth arrest-specific 1 proteins. We investigated whether silencing cyclin I expression using cyclin I-siRNA could promote an increase in H9c2 cell proliferation. It was determined that silencing cyclin I could enhance a small, but significant, increase in H9c2 cell division. Similar results were obtained for cardiomyocytes extracted from 13-day-old hearts. These results imply that the reason why cardiomyocytes in 13-day-old hearts increased cyclin I expression was probably associated with terminal growth arrest. However, the increase in p53 expression was probably associated with cardiomyocyte differentiation, rather than growth arrest.

Comparison between empirical prokinetics, Helicobacter test-and-treat and empirical endoscopy in primary-care patients presenting with dyspepsia: A one-year study

AIM: To investigate the optimal strategy to treat dyspeptic patients in primary care.

METHODS: Dyspeptic patients presenting to primary care outpatient clinics were randomly assigned to: (1) empirical endoscopy, (2) H pylori test-and-treat, and (3) empirical prokinetic treatment with cisapride. Early endoscopy was arranged if patients remained symptomatic after 2 wk. Symptom severity, quality-of-life (SF-36) as well as patient preference and satisfaction were assessed. All patients underwent endoscopy by wk 6. Patients were followed up for one year.

RESULTS: Two hundred and thirty four patients were recruited (163 female, mean age 49). 46% were H pylori positive. 26% of H pylori tested and 25% of empirical prokinetic patients showed no improvement at wk 2 follow-up and needed early endoscopy. 15% of patients receiving empirical cisapride responded well to treatment but peptic ulcer was the final diagnosis. Symptom resolution and quality-of-life were similar among the groups. Costs for the three strategies were HK$4343, $1771 and $1750 per patient. 66% of the patients preferred to have early endoscopy.

CONCLUSION: The three strategies are equally effective. Empirical prokinetic treatment was the least expensive but peptic ulcers may be missed with this treatment. The H pylori test-and-treat was the most cost-effective option.

Lansoprazole, levofloxacin and amoxicillin triple therapy vs. quadruple therapy as second-line treatment of resistant Helicobacter pylori infection

AIM

To test the efficacy of levofloxacin-based second-line therapy for resistant Helicobacter pylori infection.

METHODS

One hundred and six patients who failed H. pylori eradication were randomized to receive (i) lansoprazole 30 mg, amoxicillin 1 g, levofloxacin 500 mg, all given twice daily for 7 days (LAL); or (ii) lansoprazole 30 mg twice daily, metronidazole 400 mg thrice daily, bismuth subcitrate 120 mg and tetracycline 500 mg four times daily for 7 days (quadruple). Post-treatment H. pylori status was determined by (13)C-urea breath test.

RESULTS

Intention-to-treat and per-protocol H. pylori eradication rates were 57/60% for the LAL group and 71/76% for the quadruple group respectively. Metronidazole, clarithromycin, amoxicillin and levofloxacin resistance were found in 76%, 71%, 0% and 18% of patients, respectively. Levofloxacin resistance led to treatment failure in the LAL group. For patients with dual resistance to metronidazole and clarithromycin, the eradication rates were 79% in the LAL group (levofloxacin-sensitive) and 65% in the quadruple group (P=0.34).

CONCLUSION

Lansoprazole, amoxicillin plus levofloxacin second-line therapy is comparable with quadruple therapy in efficacy. Subjects, especially those with dual resistance to metronidazole and clarithromycin, may consider levofloxacin-based therapy for levofloxacin-sensitive strains.

Update on clarithromycin resistance in Helicobacter pylori in Hong Kong and its effect on clarithromycin-based triple therapy

AIM

To determine the antibiotic susceptibility of Helicobacter pylori and evaluate the efficacy of a clarithromycin-based triple therapy in relation to antibiotic resistance.

METHODS

Consecutive patients referred for upper endoscopy due to dyspeptic symptoms were recruited. Gastric biopsies were obtained for the CLO test, histology and culture. Antibiotic susceptibility was assessed by the E-test. Patients with H. pylori infection received rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily for 7 days.

RESULTS

Of 234 patients recruited, 124 were H. pylori-positive and culture was successful in 102 patients. The updated prevalences of resistance to clarithromycin, amoxicillin and metronidazole were 7.8, 0 and 39.2%, respectively. A total of 86 patients received 1-week triple therapy with rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily, and 81 patients attended the follow-up test. Eradication rates by per-protocol and intention-to-treat analysis were 92.6 and 87.2%, respectively. The eradication rate by per protocol was significantly higher in patients with clarithromycin-susceptible strains than in those with clarithromycin-resistant strains (98.6 vs. 28.6%, p < 0.001).

CONCLUSION

Clarithromycin resistance reduces the clinical efficacy of clarithromycin-based triple therapy. However, due to the low prevalence of clarithromycin resistance, clarithromycin-based therapy is still the first choice for clinical use.

A pilot study of participation in faecal occult blood testing and screening colonoscopy after health education in Hong Kong

Colorectal cancer is the second commonest cancer in Hong Kong. The screening behaviour of the Chinese population has not been assessed. The aim of this study is to report a pilot study of educating and subsequent evaluation of colorectal cancer screening behaviour in the Hong Kong Chinese population. Subjects were invited to attend a free health talk on colorectal cancer. Both self-paid faecal occult blood testing (FOBT) and free screening colonoscopy were offered after the education programme. Of the participants taking part in the education programme 113/119 (95%) completed the FOBT. Of the FOBT 8/113 (7%) showed positive result and three patients had neoplasia at colonoscopy. Twenty-five patients with negative FOBT also completed colonoscopy; two had adenomas. Screening colonoscopy after FOBT was accepted by 28% of subjects. Those younger than 65 years and those with a positive FOBT (7/8 versus 25/105 for those with negative FOBT, P=0.0003) were more likely to agree to screening colonoscopy. In conclusion, health education is important for ensuring high acceptance and implementation of colorectal cancer screening in Hong Kong Chinese. FOBT is an acceptable and feasible screening method in Hong Kong.

Standard treatment for Helicobacter pylori infection is suboptimal in non-ulcer dyspepsia compared with duodenal ulcer in Chinese

BACKGROUND

Recent studies suggest that the Helicobacter pylori eradication rate in patients with non-ulcer dyspepsia is lower when compared to patients with peptic ulcer diseases.

AIM

The aim of this study was to study the efficacy of triple therapy for H. pylori infection in patients with duodenal ulcer vs. patients with non-ulcer dyspepsia.

METHODS

A total of 582 Chinese patients with proven H. pylori infection were recruited to receive: omeprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg all given twice daily for 7 days (OCA regime). Endoscopy with rapid urease test, histology and culture were performed before treatment. Post-treatment H. pylori status was determined by (13)C-urea breath test. Metronidazole, clarithromycin and amoxicillin resistance was defined as minimum inhibitory concentration (MIC) of >8 microg/mL, >1 microg/mL and >1 microg/mL, respectively.

RESULTS

A significantly higher (intention-to-treat/per-protocol) eradication rate was found in patients with duodenal ulcer than those with non-ulcer dyspepsia (91/94% vs. 84/88% respectively, P = 0.011 and P = 0.016). Clarithromycin resistance rate was higher in patients with non-ulcer dyspepsia than those with duodenal ulcer (14% vs. 6%, P = 0.015). Clarithromycin resistance (40% vs. 5%, P < 0.001, OR 12, 95% CI: 5.7-24.3) and the diagnosis of non-ulcer dyspepsia (91% vs. 84%, P = 0.011, OR 2.0, 95% CI: 1.2-3.3) significantly affected the success of H. pylori eradication.

CONCLUSION

Clarithromycin resistance accounts for the significantly lower and suboptimal H. pylori eradication rate of OCA regimen in Chinese patients with non-ulcer dyspepsia compared to those with duodenal ulcer.

Onset and disappearance of reflux symptoms in a Chinese population: a 1-year follow-up study

BACKGROUND

The natural history of gastro-oesophageal reflux disease in Asian population has not been studied before.

AIM

To study the onset and disappearances of reflux symptoms over a 1-year period in the Chinese population.

METHODS

A population-based telephone survey was performed in 2002 and repeated 1 year later. The change in prevalence rate, onset and disappearance of gastro-oesophageal reflux disease, and the change in diagnoses were assessed. Factors associated with the onset and disappearance of gastro-oesophageal reflux disease were studied.

RESULTS

A total of 712 subjects completed the first and second survey. The annual, monthly and weekly prevalence of gastro-oesophageal reflux disease were 34.1%, 10.1% and 2.7% respectively. The onset rate (per 1000 person-year) and disappearance rate of any gastro-oesophageal reflux disease and frequent gastro-oesophageal reflux disease (> or = monthly symptoms) were 209, 40; and 395, 243 respectively. Forty-four percentage of gastro-oesophageal reflux disease subjects changed their diagnoses in 2003. By multiple logistic regression analysis, high anxiety score (OR: 1.2, 95% CI: 1.1-1.2) and higher educational level (OR: 2.7, 95% CI: 1.3-6.3) were associated with the onset of gastro-oesophageal reflux disease; while the frequency of acid regurgitation (OR: 0.35, 95% CI: 0.17-0.70) and use of antisecretory therapy (OR: 0.50, 95% CI: 0.28-0.89) were associated with the disappearance of gastro-oesophageal reflux disease.

CONCLUSION

The prevalence of gastro-oesophageal reflux disease is stable over 1 year. Higher anxiety score and higher educational level were associated with the onset of gastro-oesophageal reflux disease, while lower frequency of reflux symptoms and infrequent use of antisecretory therapy were associated with the disappearance of gastro-oesophageal reflux disease in a Chinese population.

Effect of cyclo-oxygenase inhibitors on Helicobacter pylori susceptibility to metronidazole and clarithromycin

BACKGROUND

We previously reported that aspirin inhibited Helicobacter pylori growth and suppressed the mutagenic effect of metronidazole.

AIM

To determine the effects of a cyclo-oxygenase (COX)-2-specific inhibitor, SC-236, and a non-selective COX inhibitor, indometacin, on the growth, urease activity and antimicrobial susceptibility of H. pylori.

METHODS

Three H. pylori reference strains, and 18 clinical isolates were treated with SC-236 or indometacin for 24 and 48 h. Growth, urease activity and susceptibility to clarithromycin and metronidazole of the bacteria were assessed by viable colony counting, spectrophotometry and E-test respectively.

RESULTS

SC-236 and indometacin inhibited H. pylori growth in a dose-dependent manner with the lowest inhibitory concentrations of 0.03 and 0.1 mm, and the lethal concentrations of 0.09 and 0.3 mm, respectively. The numbers of CFU/mL in Brucella broth containing 0.09 mm SC-236 were 2 log lower at 24 h, and even 3 log lower at 48 h than that at 0 h (P = 0.035, compared with the vehicle control). Treatment of 0.3 mm indometacin reduced the number of CFU/mL by 1 log at 24 h compared with that at 0 h (P = 0.037 compared with the vehicle control). Helicobacter pylori urease activity began to decrease with 0.06 mm SC-236 at 24 h (P = 0.016), and 0.3 mm indometacin at 48 h (P = 0.025). MICs of metronidazole and clarithromycin against H. pylori were decreased significantly in the presence of 0.03 mm SC-236 or 0.1 mm indometacin (all P < 0.001).

CONCLUSION

Both SC-236 and indometacin suppressed the growth and urease activity of H. pylori in a dose-dependent manner, and increased its susceptibility to the antibiotics.

Aberrant epithelial expression of trefoil family factor 2 and mucin 6 in Helicobacter pylori infected gastric antrum, incisura, and body and its association with antralisation

AIMS

To determine gastric expression of trefoil family factor 2 (TFF2) and MUC6 in Helicobacter pylori positive and negative subjects, and its association with antralisation at the gastric incisura.

METHODS

Gastric biopsies from the antrum, incisura, and body of 76 dyspeptic patients without ulcers were used for the determination of H. pylori infection, histological changes, and epithelial TFF2 and MUC6 expression.

RESULTS

In the foveola, the rates of TFF2 and MUC6 immunostaining were greater in H. pylori infected (n = 27) than in uninfected patients (n = 49) at the antrum (59.3% v 4.1% for TFF2 and 63.0% v 4.1% for MUC6; both p < 0.001) and incisura (44.4% v 2.0% for TFF2 and 48.1% v 0% for MUC6; both p < 0.001). In the deeper glands, the rates were also greater in H. pylori infected than in uninfected patients at the incisura (85.2% v 22.4% for both TFF2 and MUC6; p < 0.001). Antral-type mucosa was present at the incisura in 28 of the 76 patients. TFF2 and MUC6 expression in the foveola and deeper glands was significantly associated with antral-type mucosa, independent of H. pylori status.

CONCLUSIONS

Helicobacter pylori infection increases the expression of TFF2 and MUC6 in the gastric epithelium. Aberrant TFF2 and MUC6 expression is associated with antralisation of gastric incisura.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

One-week ranitidine bismuth citrate, amoxicillin and metronidazole triple therapy for the treatment of Helicobacter pylori infection in Chinese

BACKGROUND

We have previously shown that ranitidine bismuth citrate-based, clarithromycin-containing triple therapy achieves a higher eradication rate than proton pump inhibitor-based regimens in areas with a high prevalence of metronidazole resistance.

AIM

To evaluate whether this higher efficacy of ranitidine bismuth citrate over proton pump inhibitor can be extended to non-clarithromycin-containing regimens.

METHODS

Helicobacter pylori-positive dyspeptic patients were randomized to receive either ranitidine bismuth citrate, 400 mg, amoxicillin, 1000 mg, and metronidazole, 400 mg, or omeprazole, 20 mg, amoxicillin, 1000 mg, and metronidazole, 400 mg, each given twice daily for 1 week. H. pylori eradication was confirmed by 13C-urea breath test 5 weeks later. The side-effects of the treatments were documented.

RESULTS

Two hundred and twenty-nine patients were eligible for analysis. By intention-to-treat and per protocol analysis, the eradication rates were 77% and 79%, respectively, in the ranitidine bismuth citrate-amoxicillin-metronidazole group and 77% and 82%, respectively, in the omeprazole-amoxicillin-metronidazole group (P = 0.58 and P = 0.65). However, patients in the omeprazole-amoxicillin-metronidazole group reported a significantly higher incidence of minor side-effects when compared to those in the ranitidine bismuth citrate-amoxicillin-metronidazole group (P = 0.001).

CONCLUSIONS

Ranitidine bismuth citrate-amoxicillin-metronidazole was equally as effective as omeprazole-amoxicillin-metronidazole triple therapy, and may be considered as an alternative non-clarithromycin-based regimen in the Chinese population.

Double blind, randomised, placebo controlled study of four weeks of lansoprazole for the treatment of functional dyspepsia in Chinese patients

BACKGROUND

The use of proton pump inhibitors for the treatment of functional dyspepsia is controversial and the role of Helicobacter pylori infection in functional dyspepsia is uncertain.

AIM

To evaluate the efficacy of different doses of lansoprazole for the treatment of functional dyspepsia in Chinese patients.

METHOD

Patients with a clinical diagnosis of functional dyspepsia according to the Rome II criteria and normal upper gastrointestinal endoscopy were recruited and randomised to receive: (1) lansoprazole 30 mg, (2) lansoprazole 15 mg, or (3) placebo, all given daily for four weeks. Dyspepsia symptom scores and quality of life (SF-36 score) were evaluated before and four weeks after treatment.

RESULTS

A total of 453 patients were randomised. There was no difference in the proportion of patients with complete symptom relief in the lansoprazole 30 mg (23%) and lansoprazole 15 mg (23%) groups compared with the placebo group (30%). The proportion of H pylori positive patients with a complete response was similar with lansoprazole 30 mg (34%) and lansoprazole 15 mg (20%) versus placebo (22%). All symptom subgroups (ulcer-like, dysmotility-like, reflux-like, and unspecified dyspepsia) had similar proportions of patients with complete symptom relief after treatment.

CONCLUSION

Proton pump inhibitor treatment is not superior to placebo for the management of functional dyspepsia in Chinese patients.

Simultaneous analysis of T cell clonality and cytokine production in rheumatoid arthritis using three-colour flow cytometry

In this study we examined the cytokine production by T cells and TCRVbeta subsets in peripheral blood (PB) and synovial fluid (SF) from six RA patients and PB from 10 normal subjects, using three-colour flow cytometry. In two RA subjects we assessed T cell clonality by RT PCR using TCRBV family-specific primers and analysed the CDR3 (complementarity determining region 3) length by GeneScan analysis. A high percentage of IFN-gamma- and IL-2- producing cells was observed among the PB T cells in both the RA patients and normal controls and among the SF T cells in RA patients. In contrast, the percentage of T cells producing IL-4 and IL-5 was small among PB T cells in both RA patients and normal controls and among SF T cells in RA patients. There was no significant difference in the production of IFN-gamma, IL-2 and IL-5 between the two compartments (PB and SF); however, there were significantly more IL-4-producing cells in SF. Molecular analysis revealed clonal expansions of four TCRBV families in SF of two of the RA patients studied: TCRBV6.7, TCRBV13.1 and TCRBV22 in one and TCRBV6.7, TCRBV21.3 and TCRBV22 in the second. These expansions demonstrated cytokine expression profiles that differed from total CD3+ cells, implying that T cell subsets bearing various TCR-Vbeta families may have the potential to modulate the immune response in RA patients.

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.

Normal 24-hour ambulatory proximal and distal gastroesophageal reflux parameters in Chinese

OBJECTIVE

To quantify normal proximal and distal oesophageal acid parameters in healthy Chinese.

DESIGN

Observational study.

SETTING

University teaching hospital, Hong Kong.

SUBJECTS AND METHODS

Twenty healthy adults who were not on medication and were free from gastrointestinal symptoms were recruited by advertisement. Ambulatory oesophageal acid (pH<4) exposure parameters were recorded at distal and proximal sites, 5 and 20 cm, respectively above the lower oesophageal sphincter.

RESULTS

The 95th percentile for reflux parameters assessed in the distal/proximal oesophagus were: percent total time pH<4, 4.6/0.7%; percent upright time pH<4, 7.0/1.1%; percent supine time pH<4, 4.5/0.5%; number of reflux episodes, 73/12; number of reflux episodes with pH<4 for >5 minutes, 4/0; and the longest single acid exposure episode, 11.2/3.0 minutes.

CONCLUSION

Physiological gastroesophageal reflux occurs in healthy Chinese. These initial data provide a preliminary reference range that could be utilised by laboratories studying Chinese subjects.

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.

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.

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.

Implications of a high placental ratio in pregnancies with appropriate-for-gestational age neonates

OBJECTIVE

To determine the relationship between the placental weight to birth weight ratio (placental ratio) with maternal pre-pregnancy weight, gestational weight gain, and neonatal outcome in non-diabetic pregnancies resulting in appropriate-for-gestational age (AGA) infants.

METHODS

A retrospective study was performed on 593 patients with singleton pregnancies, normal results in the 75-gram oral glucose tolerance test and who delivered AGA newborns within a 1-year period. The patients were categorized into high placental ratio (> mean +1 SD based on previous data, n = 113 or 19.1%) and normal ratio groups for the comparison of maternal and neonatal anthropometric parameters.

RESULTS

The high placental ratio group had a higher pre-pregnancy weight, body mass index, placental weight, and incidence of low Apgar score, but decreased absolute and percentage gestational weight gain, gestational age, and birth weight. After controlling for pre-pregnancy weight and gestational age, only the correlation between placental weight and percent weight gain remained significant.

CONCLUSION

Our finding suggests that a high placental ratio can identify AGA newborns who are disproportionately small relative to maternal size, and may reflect some form of fetal growth impairment.

Distribution of distinct vacA, cagA and iceA alleles in Helicobacter pylori in Hong Kong

BACKGROUND

There is a substantial genetic heterogeneity among Helicobacter pylori strains, and certain genotypes have been suggested to be associated with the virulence of this pathogen. The aim of this study was to investigate the distribution of H. pylori vacA, cagA and iceA genotypes and their association with duodenal ulcer disease in Hong Kong.

MATERIALS AND METHODS

Gastric biopsies of 72 H. pylori infected patients were analyzed by specific polymerase chain reactions.

RESULTS

Of the 72 cases, 69 (95.8%) had vacA signal sequence s1c strains, and three (4.2%) had s1a strains. vacA middle region sequences, m1b and m2, were detected in 23 (31.9%) and 46 (63.9%), respectively. Six (8.3%) cases contained multiple vacA subtypes. vacA s2 allele was only observed in three (4.3%) cases, which were also infected with s1c subtype. cagA was present in 64 (88.9%) of 72 patients, and iceA1 subtype was detected in 46 (63.9%) cases. Neither cagA nor vacA and iceA were associated with duodenal ulcer disease.

CONCLUSION

The distribution of vacA, cagA and iceA alleles in H. pylori strains in Hong Kong is similar to that in east Asia. There is a difference in the distribution of genotypes between strains in Hong Kong and those in mainland China, although strains in the two regions exhibit a very close relation. The association of these virulence genes and duodenal ulcer disease needs reappraisal, particularly under geographic considerations.