Bile reflux gastritis and intestinal metaplasia at the cardia.

BACKGROUND AND AIMS: Intestinal metaplasia (IM) at the cardia is likely to be a precursor of cardia cancer. Previous work has shown that it is associated with chronic inflammation attributable to either gastro-oesophageal reflux disease (GORD) or Helicobacter pylori infection. An alternative aetiological factor is bile reflux. Duodenogastric reflux brings about histological changes in the gastric mucosa that can be graded and used to calculate a bile reflux index (BRI). We used the BRI to assess whether reflux of bile plays a part in the development of cardia IM. METHODS: Histological changes in simultaneous gastric antrum and cardia biopsies from 267 dyspeptic patients were independently graded by two pathologists. The association between cardia IM and age, sex, clinical group, H pylori status, increased BRI (>14), and inflammation at the cardia were evaluated using logistic regression. RESULTS: A total of 226 patients had adequate cardia and antral biopsies; 149 had GORD and 77 had non-ulcer dyspepsia. Cardia IM was present in 66 (29%) patients, of whom 28 (42%) had complete IM. Increasing age, male sex, chronic inflammation, and a high BRI emerged as significant independent associations with cardia IM. Clinical group and H pylori status were not independent risk factors. CONCLUSIONS: Histological evidence of bile reflux into the stomach is associated with cardia IM. This could have an important bearing on carcinogenesis at this site.

Bile reflux gastritis and Barrett's oesophagus: further evidence of a role for duodenogastro-oesophageal reflux?

BACKGROUND: There is increasing evidence that reflux of bile plays a part in the pathogenesis of Barrett's oesophagus. Bile injury to the gastric mucosa results in a "chemical" gastritis in which oedema and intestinal metaplasia are prominent. AIM: To determine if patients with Barrett's oesophagus have more bile related changes in antral mucosa than patients with uncomplicated gastro-oesophageal reflux disease (GORD) or non-ulcer dyspepsia (NUD). PATIENTS AND METHODS: Patients were identified by a retrospective search of pathology records and those with a clinically confirmed diagnosis of either Barrett's oesophagus or reflux oesophagitis who had oesophageal and gastric biopsies taken at the same endoscopy and had no evidence of Helicobacter pylori infection entered the study. Control biopsies were taken from H pylori negative NUD patients. Antral biopsies were examined "blind" to clinical group and graded for a series of histological features from which the "reflux gastritis score" (RGS) and "bile reflux index" (BRI) could be calculated. The reproducibility of these histological scores was tested by a second pathologist. RESULTS: There were 100 patients with Barrett's, 61 with GORD, and 50 with NUD. The RGSs did not differ between groups. BRI values in the Barrett's group were significantly higher than those in GORD subjects (p=0.014) which in turn were higher than those in NUD patients (p=0.037). Similarly, the frequency of high BRI values (>14) was significantly greater in the Barrett's group (29/100; 29%) than in the GORD (9/61; 14.8%) or NUD (4/50; 8%) group. However, agreement on BRI values was "poor", indicating limited applicability of this approach. CONCLUSION: Patients with Barrett's oesophagus have more evidence of bile related gastritis than subjects with uncomplicated GORD or NUD. The presence of bile in the refluxate could be a factor in both the development of "specialised" intestinal metaplasia and malignancy in the oesophagus.

Whipple's disease revisited.

Whipple's disease has traditionally been considered to be a rare multisystem disorder dominated by malabsorption. The recent identification of the Whipple's disease bacillus has, using polymerase chain reaction based assays, fueled advances in the investigation, diagnosis, and management of this disease. This leader reviews the aetiology, clinical manifestations, investigation, and treatment of Whipple's disease in the light of this new information.

Correlation between epithelial cell proliferation and histological grading in gastric mucosa.

AIM: To determine if there is a correlation between the histological findings in the gastric mucosa and the degree of cell proliferation in gastric antral biopsies. METHODS: Cell proliferation in gastric antral biopsies was determined by in vitro bromodeoxyuridine labelling. Histological sections were assessed using the Sydney System. RESULTS: There was a positive correlation between antral mucosal cell proliferation and the acute inflammatory cell infiltrate (r = 0.29; p = 0.03). There was a stronger correlation with the chronic inflammatory cell infiltrate (r = 0.53; p < 0.0001) and the density of H pylori colonisation (r = 0.54; p < 0.0001). There was no correlation between gastric epithelial proliferation and the degree of atrophy. Stepwise multiple regression indicates that the only independent predictor of epithelial cell proliferation is the density of H pylori colonisation (p < 0.0001). CONCLUSIONS: H pylori increases gastric epithelial cell proliferation through the mucosal inflammatory response and probably by other means. The strong correlation between epithelial proliferation, the chronic inflammatory cell infiltrate, and the density of H pylori colonization may have implications for gastric carcinogenesis.

The optimal antibiotic combination in a 5-day Helicobacter pylori eradication regimen.

BACKGROUND: Current guidelines for Helicobacter pylori eradication recommend 7 days of a proton-pump inhibitor, clarithromycin (C), and either metronidazole (M) or amoxycillin (A). A shorter course would be cheaper and could be as effective. AIM: This study was designed to investigate the efficacy of three 5-day regimens based on lansoprazole (L). METHODS: 168 dyspepsia patients with H. pylori infection were randomized to receive a 5-day course of either LCM, LAC or CALM, and a 13C-urea breath test was performed after 4 weeks to assess eradication. RESULTS: 160 patients completed the study. Intention-to-treat eradication rates were as follows: LCM 81%, LAC 59%, CALM 88%. LCM and CALM gave significantly better eradication rates than LAC. There was no significant difference in adverse events across the three groups. Logistical regression analysis showed that the specific regimen used and the age of the patient were the only factors influencing eradication outcome. CONCLUSIONS: Five days of CALM yields acceptable eradication rates, and is cheaper than conventional 7-day proton pump inhibitor-triple therapy. It appears to offer good results in metronidazole-resistant strains of H. pylori. A randomized trial comparing 5-day CALM with conventional 7-day therapy is needed before this regimen can be recommended for routine use.

Reactive oxygen species activity and lipid peroxidation in Helicobacter pylori associated gastritis: relation to gastric mucosal ascorbic acid concentrations and effect of H pylori eradication.

BACKGROUND: Helicobacter pylori is an independent risk factor for gastric cancer, and this association may be due to the bacterium causing reactive oxygen species mediated damage to DNA in the gastric epithelium. High dietary ascorbic acid intake may protect against gastric cancer by scavenging reactive oxygen species. AIMS: To assess reactive oxygen species activity and damage in gastric mucosa in relation to gastric pathology and mucosal ascorbic acid level, and to determine the effect of H pylori eradication on these parameters. PATIENTS: Gastric biopsy specimens were obtained for analysis from 161 patients undergoing endoscopy for dyspepsia. METHODS: Reactive oxygen species activity and damage was assessed by luminol enhanced chemiluminescence and malondialdehyde equivalent estimation respectively. Ascorbic acid concentrations were measured using HPLC. RESULTS: Chemiluminescence and malondialdehyde levels in gastric mucosa were higher in patients with H pylori gastritis than in those with normal histology. Successful eradication of the bacterium led to decreases in both parameters four weeks after treatment was completed. Gastric mucosal ascorbic acid and total vitamin C concentrations were not related to mucosal histology, but correlated weakly with reactive oxygen species activity (chemiluminescence and malodialdehyde levels). CONCLUSIONS: Data suggest that reactive oxygen species play a pathological role in H pylori gastritis, but mucosal ascorbic acid is not depleted in this condition.

Clinical and histological associations of cagA and vacA genotypes in Helicobacter pylori gastritis.

AIMS: To determine the relation among the cytotoxin associated gene (cagA) and vacuolating cytotoxin gene (vacA) status of Helicobacter pylori isolates, the associated clinical diseases, and the severity and pattern of chronic gastritis. METHODS: Helicobacter pylori was cultured from gastric biopsies obtained from dyspeptic patients. DNA was extracted from the isolates and the cagA and vacA status determined by the polymerase chain reaction (PCR). The prevalence of the different cagA and vacA genotypes in three clinical groups, duodenal ulcer, gastric ulcer, and non-ulcer dyspepsia was compared. The histological features in sections from two antral and two corpus biopsies were graded by one blinded observer. The grades were compared with age and sex matched groups with different cagA and vacA genotypes, and with duodenal ulcers, or non-ulcer dyspepsia. RESULTS: Isolates from 161 patients were included. One hundred and nine (68%) harboured a cagA+ strain and 143 (89%) harboured a vacA s1 strain. The prevalence of cagA+ strains in duodenal ulcer patients (94%) was highly significantly greater than in those with non-ulcer dyspepsia (56%). However, of the patients infected with a cagA+ strain, almost equal numbers had non-ulcer dyspepsia or peptic ulceration. Chronic inflammation, polymorph activity, surface epithelial degeneration, atrophy, and intestinal metaplasia were all significantly more severe in the cagA+ than in the cagA- group, whereas only corpus epithelial degeneration was significantly more severe in the vacA s1 group compared with the vacA s2 group. Patients infected with cagA+ strains were almost four times more likely to have antral intestinal metaplasia than cagA- patients. An antral predominant gastritis was present in duodenal ulcer patients compared with matched non-ulcer dyspepsia patients, but this was not attributable to cagA or vacA status. CONCLUSIONS: Helicobacter pylori strains showing cagA positively and the vacA s1 genotype are associated with more severe gastritis but these virulence factors do not appear to determine the overall pattern. The pattern is closely linked to clinical disease. Therefore, it is likely that the nature of the disease complicating chronic infection is determined by host and environmental factors, while bacterial factors determine the magnitude of the risk of developing such disease.

Do patients need to fast for a 13C-urea breath test?

OBJECTIVE: The 13C-urea breath test (13C-UBT) is a useful non-invasive method of diagnosing Helicobacter pylori infection. One of its limitations, however, is that patients have to fast for 4 h before testing. We have compared the accuracy of a non-fasting 13C-UBT (NF13C-UBT) with a fasting 13C-UBT (F13C-UBT) test and against a gold standard. DESIGN: An unblinded prospective crossover study. METHODS: H. pylori status was assessed by histology, culture and rapid urease test. Patients were defined as H. pylori positive if two or more tests gave a positive result and negative if all tests were negative. H. pylori status was indeterminate if only one test gave a positive result. Following endoscopy patients had a F13C-UBT and then a further NF13C-UBT up to 14 days later after eating two slices of toast with jam or honey and tea or coffee. RESULTS: Of the 222 patients recruited to the study, 123 were gold standard H. pylori positive and 94 were negative with five patients having indeterminate status. Compared to this gold standard the NF13C-UBT had a 98% sensitivity and 96% specificity and the F13C-UBT had a 96% sensitivity and 97% specificity. The NF13C-UBT and F13C-UBT agreed in 217/222 (98%) cases. CONCLUSION: Relaxation of the fasting state does not reduce the accuracy of the 13C-UBT, making this test more convenient for patients.

The Detection of H. pylori by the Polymerase Chain Reaction.

A number of methods are currently available for the detection of Helicobacter pylori, including serology, culture, histology, and isotope breath tests. All have relative advantages and disadvantages of sensitivity, specificity, convenience, expense, and immediacy. The polymerase chain reaction (PCR) was an obvious choice of test once the technique became available to many laboratories. PCR tests for various bacteria, including H. pylori, are available on a wide range of specimens, including cultures and direct clinical samples. The ideal PCR test for H. pylori would be highly sensitive and specific, cheap if performed in bulk, and could produce results much faster than would be possible with culture.

Serum and gastric luminal epidermal growth factor in Helicobacter pylori-associated gastritis and peptic ulcer disease.

BACKGROUND: Helicobacter pylori is the cause of chronic (type B) gastritis, duodenal ulceration (DU), and gastric ulceration (GU). Smoking is associated with delayed ulcer healing. Epidermal growth factor (EGF) is produced in the salivary and Brunner's glands of the upper gastrointestinal tract, inhibits gastric acid secretion, and is a powerful mitogen. MATERIALS AND METHODS: We sought to determine gastric luminal EGF (GL-EGF) in smokers and patients with Hp-associated DU and the effects of Hp eradication. Our aim was to determine GL-EGF in patients with GU and the effect of ulcer healing and to measure serum EGF in patients with Hp gastritis with or without DU disease. RESULTS: GL-EGF was reduced in smokers compared to controls (p = .008). Subjects with HP gastritis had reduced GL-EGF compared to controls (p = .0002). There was no difference in GL-EGF between Hp-positive subjects who had DU and those with chronic gastritis alone. Eradication of Hp from those patients with DU had no effect on the low levels of GL-EGF. There was no difference between GL-EGF in Hp gastritis alone and in Hp-associated active GU. GL-EGF fell after ulcer healing (p = .04), a difference confirmed by analysis of paired samples from patients before and after ulcer healing (p = .03). There was no difference in serum EGF between controls and subjects with Hp infection. There was no difference in serum EGF in subjects with DU associated and non-ulcer-associated gastritis. CONCLUSIONS: Subjects with Hp gastritis, or those who smoke, had low concentrations of GL-EGF regardless of whether DU was present. Eradication of Hp did not return the concentrations of GL-EGF to normal in DU subjects. Individuals and Hp gastritis and inactive GU had low levels of GL-EGF compared to non-ulcer Hp infection. The relative increase in GL-EGF that occurred with ulceration of the gastric mucosa may have resulted from the development of an ulcer-associated cell lineage. Serum EGF did not play a role in the pathogenesis of Hp gastritis or of associated DU ulcer disease.

Ascorbic acid may protect against human gastric cancer by scavenging mucosal oxygen radicals.

High dietary ascorbic acid intake appears to protect against gastric cancer. This may be due to its action as a scavenger of reactive radical species formed in the gastric mucosa, resulting in a reduced level of radical-mediated DNA damage. We have studied 82 patients, of whom 37 had Helicobacter pylori-associated gastritis, a condition which predisposes to gastric cancer. Using electron paramagnetic resonance (EPR) spectroscopy we have demonstrated, for the first time, that ascorbyl radicals are generated in human gastric mucosa, presumably as a result of scavenging of free radicals by ascorbic acid. Quantification of ascorbyl radicals demonstrates that there is a higher concentration in those patients with H.pylori gastritis compared with subjects with normal histology (P < 0.01). We also found gastric mucosal luminol-enhanced chemiluminescence and malondialdehyde concentrations (which are believed to be markers of radical generation and tissue damage) to be higher in patients with H.pylori gastritis compared with those with normal histology (P < 0.001 and P < 0.01 respectively). The observed concentrations of the ascorbyl radical correlate with the level of luminol-enhanced chemiluminescence (r = 0.41, P < 0.001), but not with malondialdehyde concentrations (r = 0.08, P = 0.47). Mucosal ascorbic acid and total vitamin C concentrations did not vary between histological groups, nor did they correlate with mucosal levels of the ascorbyl radical, chemiluminescence or malondialdehyde. These data suggest that ascorbic acid is acting as a scavenger of free radicals generated in human gastric mucosa. The experiments therefore provide direct supportive evidence for the hypothesis that ascorbic acid protects against gastric cancer by scavenging reactive radical species which would otherwise react with DNA, with resultant genetic damage.

Mycobacterium paratuberculosis DNA not detected in Crohn's disease tissue by fluorescent polymerase chain reaction.

The role of mycobacteria in the aetiology of Crohn's disease has been a contentious subject for many years. Mycobacterium paratuberculosis is known to cause a chronic granulomatous enteritis in animals (Johne's disease) and has been implicated as a possible infectious cause of Crohn's disease. However this fastidious organism is only rarely detected by conventional microbiological techniques. This study used oligonucleotide primers to the species-specific M paratuberculosis IS900 DNA insertion element and the polymerase chain reaction to amplify any M paratuberculosis DNA from intestinal tissue DNA extracts. One oligonucleotide primer was fluorochrome-labelled and the presence of fluorescent amplified product was determined using an automated DNA sequencer with a computerised gel-scanning laser. This method was shown capable of detecting 1-2 mycobacterial genomes. Intestinal tissue samples were obtained from 68 patients with histologically confirmed Crohn's disease, 49 patients with histologically confirmed ulcerative colitis, and 26 non-inflammatory bowel disease controls. In no case was M paratuberculosis detected in any of the inflammatory bowel disease tissue samples and only one non-inflammatory bowel disease case was positive. These results do not support the hypothesis that M paratuberculosis has an aetiological role in Crohn's disease.

Helicobacter pylori infection and dental care.

Sixty two patients (mean age 45.6 years) were assessed for oral hygiene and periodontal disease by dental examination before endoscopy. Information about oral care, smoking, and dentures was obtained and samples of dental plaque collected. The presence of Helicobacter pylori in plaque as sought by culture and polymerase chain reaction (PCR), and gastric antral biopsy specimens were taken for histological examination. Although H pylori was detected in the antral specimens of 34 patients (54%) all of the cultures of dental plaque were negative, and PCR was only positive from the dentures of one patient. Smokers had poor oral hygiene, visited their dentist less often, and brushed their teeth less frequently. There was no correlation of H pylori gastritis with either dental hygiene or periodontal disease. These results suggest that dental plaque or dentures are not an important reservoir for H pylori and are probably not a significant factor in transmission of the organism. The conflicting results in published works may be caused by differences in sample collection, culture techniques, or oral contamination from gastric juice as a result of gastro-oesophageal reflux at the time of endoscopy.

Cell proliferation in the gastric corpus in Helicobacter pylori associated gastritis and after gastric resection.

Patients who have undergone gastric resection are at higher risk of developing gastric carcinoma than normal subjects, and bile reflux is believed to play a role in carcinogenesis. An increase in mucosal cell proliferation increases the likelihood of a neoplastic clone of epithelial cells emerging, particularly where there is chronic epithelial injury associated with bile reflux. Helicobacter pylori is considered a major risk factor for gastric cancer in the intact stomach. It has been shown previously that antral cell proliferation is increased in H pylori gastritis and falls to normal levels after eradication of the organism. Little is known of corpus cell proliferation in H pylori gastritis or after gastric resection. Using in vitro bromodeoxyuridine labelling of endoscopic biopsy specimens we have found that corpus cell proliferation is increased in H pylori gastritis. Cell proliferation was greater in corpus biopsy specimens of resected stomachs than in H pylori gastritis. Subgroup analysis of patients who had undergone gastric resection indicated that those positive for H pylori had higher levels of cell proliferation than those negative for the organism. These findings provide further evidence that H pylori and bile have a role in gastric carcinogenesis and suggest that their presence has a synergistic effect on gastric epithelial cell proliferation.

Cell proliferation in Helicobacter pylori associated gastritis and the effect of eradication therapy.

Helicobacter pylori causes chronic (type B) gastritis. The 'intestinal' form of gastric cancer arises against a background of chronic gastritis, and prospective epidemiological studies have shown that H pylori is a major risk factor for this. An increase in mucosal cell proliferation increases the likelihood of a neoplastic clone of epithelial cells emerging where there is chronic epithelial cell injury associated with H pylori gastritis. In vitro bromodeoxyuridine labelling of endoscopic antral biopsy specimens was used to measure mucosal cell proliferation in H pylori associated gastritis before and after therapy for H pylori triple infection. Cell proliferation was increased in H pylori associated gastritis patients compared with normal controls and patients with H pylori negative chronic gastritis (p = 0.0001; Tukey's Studentised range). There was no difference in antral epithelial cell proliferation between duodenal ulcer and non-ulcer subjects infected with H pylori (p = 0.62; Student's t test). Antral mucosal cell proliferation fell four weeks after completing triple therapy, irrespective of whether or not H pylori had been eradicated (p = 0.0001). At retesting six to 18 months later (mean = 12 months), however, those in whom H pylori had not been successfully eradicated showed increased mucosal proliferation compared with both H pylori negative subjects at a similar follow up interval and all cases (whether H pylori positive or negative) four weeks after completion of triple therapy (p = 0.024). These findings suggest that H pylori infection causes increased gastric cell proliferation and in this way may play a part in gastric carcinogenesis.

Adaptation of Helicobacter pylori to aerobic growth.

Two of 23 strains of Helicobacter pylori adapted from microaerobic to aerobic growth on blood agar plates incubated in humidified air. The air-adapted strains remained urease and phenylalanine deaminase positive and did not require the buffering effect of an enriched CO2 atmosphere for growth. The significance of this phenomenon remains to be determined as the two strains capable of aerobic metabolism were laboratory-adapted.

Identification of Helicobacter pylori DNA in the mouths and stomachs of patients with gastritis using PCR.

AIMS: To determine the prevalence of Helicobacter pylori colonisation in the mouths of patients with H pylori gastritis. METHODS: A nested polymerase chain reaction test for the 16S ribosomal RNA gene of H pylori was used on saliva, dental plaque, gastric juice and gastric biopsy specimens from patients attending a dyspepsia clinic. RESULTS: Thirteen patients had histologically confirmed Helicobacter associated gastritis. Twelve of these had positive gastric aspirates by PCR. Five had at least one positive oral specimen. Eight patients with normal gastric biopsy specimens had no PCR positive oral specimens or gastric aspirates. All, however, had PCR positive gastric biopsy specimens. In an attempt to determine the origin of these positive results in normal patients, it was shown that biopsy forceps could contaminate specimens with DNA from previous patients. CONCLUSION: The demonstration of the organism in the mouths of a substantial proportion of dyspeptic patients has major implications for the spread of H pylori and identifies a potential source for reinfection following eradication of the organism from the stomach.

Testicular seminoma metastasizing to palatine tonsil.

Patients presenting with Stage I seminoma of the testis have an excellent prognosis after treatment by orchidectomy and prophylactic radiotherapy to the paraaortic and pelvic lymph nodes. Only 2% subsequently recur but relapse in these cases has been reported in unusual sites such as the prostate and mesentery. We report a case of Stage I seminoma relapsing in another rare site for secondary malignant deposits, the palatine tonsil. This case further illustrates the favourable prognosis for this tumour even in cases of distant recurrence.