[Intragastric formation of ammonia in Campylobacter pylori associated gastritis. Diagnostic and pathogenetic significance]

The diagnostic relevance of measurement of ammonia (NH3) in not stimulated gastric juice in patients with campylobacter pylori associated gastritis (CPAG) is in discussion. The role of CP-urease induced NH3 in pathogenesis of active gastritis is unclear. In answering to this questions we evaluated the sensitivity and specifity of NH3-test and CLO-test in cases of CPAG (n = 50), non CPAG (n = 16) and normal gastric mucosa (n = 20). We found a 88% sensitivity and a 86% specifity for NH3-test, a sensitivity for CLO-test of 80% and a specifity rate of 87%. NH3-test correlated well with CLO-test (n = 51, p less than 0.01) and semiquantitative histological identification of CP (p less than 0.01, n = 22). On the other hand we tried to correlate the amount of NH3 in the gastric juice and the histological degree of gastritis activity (infiltration of leucocytes of the lamia propria) in CPAG (n = 78) and Non-CPAG (n = 32) and before and after therapy in CPAG (n = 9) with bismuthsubnitrate (2 g/d, 14 d). There was no correlation between the amount of NH3 and the degree of active chronic gastritis in patients with CPAG (with or without therapy) and patients with non CPAG. It seems that NH3 has a diagnostic but no pathogenetic role in the process of inflammatory activity of CPAG.

Campylobacter pylori infection in biopsy specimens of gastric antrum: laboratory diagnosis and estimation of sampling error

Campylobacter pylori infection was sought in 382 consecutive patients referred for upper gastrointestinal endoscopy. Five antral biopsy specimens were taken from each patient: one was inserted into a CLO-test to detect the urease activity of C pylori, two were sent for histological analysis where multiple sections were stained by the Warthin-Starry silver method, and two were sent for microbiological evaluation by Gram stain and culture. A patient was deemed to be infected when C pylori was cultured or seen in either the histological sections or the Gram stain of the biopsy smear. One hundred and seventy four (46%) patients were infected. Culture, Gram stain, histological examination and the CLO-test showed sensitivities of 92%, 87%, 93% and 90%, respectively. In 27 (15%) infected patients an uneven distribution of C pylori was seen between samples in the biopsy pair sent for histology. Examination of multiple sections stained with Warthin-Starry silver was more sensitive at detecting infection (93%) than examination of multiple sections from only one biopsy specimen (84%). Fifty seven of 80 patients, biopsied a median seven days (range 5 to 55) after completing colloidal bismuth subcitrate treatment, were still infected with C pylori. There was no decrease in the sensitivities of the above tests to detect infection after treatment. It is concluded that at least two antral biopsy specimens should be examined when attempting to diagnose C pylori infection by histological methods.

The prevalence of Campylobacter pylori gastritis among asymptomatic adults

To determine the prevalence of Campylobacter pylori colonization in the healthy population we studied 54 asymptomatic volunteers and 65 patients referred because of gastrointestinal symptoms. All subjects underwent gastroscopy and gastric biopsy. C. pylori was isolated from 6 volunteers (11%) and 36 patients (55%). Histologic evidence of inflammation was present in 98% of the culture-positive subjects. Linear regression analysis revealed that the prevalence of C. pylori colonization increased with age. There was no difference in the isolation rate between the two groups when adjusted for age. Four of the six culture-positive volunteers underwent repeat endoscopy and gastric biopsy 1 year later; despite remaining asymptomatic, all still had positive culture results and histologic evidence of gastritis. We conclude that the prevalence of C. pylori-associated gastritis among symptomatic patients increases with age and that the organism may be present in the gastrointestinal tract for prolonged periods without symptoms or evidence of disease progression.

Effect of sucralfate and cimetidine on duodenal ulcer-associated antral gastritis and Campylobacter pylori

The course of gastritis and Campylobacter pylori was studied in a single-blind randomized trial comparing cimetidine 200 mg three times a day and 400 mg at night and sucralfate 1 g four times a day orally for four weeks in 140 patients with proved duodenal ulcer. At least two antral biopsies were performed during endoscopy before entry and at the end of four weeks. The activity and the degree of chronic inflammation, as assessed histologically by the degree of infiltration of, respectively, polymorphs and chronic inflammatory cells, were graded blindly by two pathologists as nil, mild, moderate, or severe. The density of C. pylori, as assessed after Warthin-Starry stain, was similarly graded. Ulcer-healing rates were comparable in the cimetidine (73.2 percent) and sucralfate (79.7 percent) groups. Improvement of the activity of gastritis occurred significantly (p less than 0.05) more frequently in the sucralfate (33.3 percent) than in the cimetidine group (18.3 percent), and remained so (p less than 0.05) when only patients with healed ulcer were compared. The density of C. pylori decreased significantly in the sucralfate group after treatment (p less than 0.01) but not in the cimetidine group. The 12-month ulcer relapse rates were significantly (p less than 0.05) lower by life-table analysis in patients healed with sucralfate than in those healed with cimetidine and were unaffected by either the density of Campylobacter in either group or the improvement of the gastritis. It is concluded that sucralfate improves duodenal ulcer-associated antral gastritis and decreases the density of C. pylori, and that factors other than bacterial density and antral gastritis may be responsible for the advantage of sucralfate over cimetidine in ulcer relapse.

[Campylobacter pylori: clinical correlations and prospective comparative studies of various diagnostic techniques]

The diagnostic performance of two different urease tests and of histologic search after modified Giemsa staining to detect Campylobacter pylori (CP) colonization of the upper gastrointestinal tract was prospectively investigated in 215 esophagogastroduodenoscopies, by using a sensitive culture technique as reference. Single antral urease tests had a high specificity of 95-96%, but a limited sensitivity of 78-83%, which increased to 91-94%, when one antral and one additional body biopsy were submitted to the biochemical tests. Giemsa stains were very sensitive, but less specific. The rate of colonization was similar in antrum and body biopsies, and increased with age. There was a close association of Campylobacter pylori colonization with duodenal and to a lower degree with gastric ulcer disease, but especially with gastritic mucosal changes. CP was never detected in patients without gastritis. Therefore, submitting one antral and one body biopsy specimen to validated urease tests represents a sensitive (91-94%) and specific (93%) method to detect Campylobacter pylori colonization, which appears to be a diffuse phenomenon affecting antral and body mucosae with similar frequency.

Natural history of Campylobacter pylori in duodenal ulceration treated with an H2-antagonist

Campylobacter pylori has been associated closely with active antral gastritis and duodenal ulcer but its pathogenetic role remains uncertain. The present longitudinal study examined, prospectively, the endoscopic antral biopsies of 45 patients with duodenal ulceration, taken before and after healing of the duodenal ulcer, during remission and at relapse. The biopsies were examined for the activity and degree of chronic inflammation of the gastritis and for the occurrence and density of C. pylori by Warthin-Starry stain. Before treatment the frequency of chronic active antral gastritis was 100% and the occurrence of C. pylori was 97%. Compared with the pre-treatment state, there was no significant change in either the frequency and severity of antral gastritis, or in the occurrence and density of the bacteria in the antral mucosa at the time the duodenal ulcer healed, during remission, or at relapse. The occurrence of the bacteria was significantly more frequent during remission, than at the time when the ulcer had healed initially (P less than 0.05). These results suggest that the bacterium may not play an important pathogenetic role in ulcer healing and relapse, when patients are managed using an H2-blocker.

[Campylobacter pylori. Determination of gastric colonization and its clinical relevance]

While evidence suggesting a statistical association between Campylobacter pylori and chronic active antral gastritis is convincing, the role which the organism may play in the pathogenesis of this condition and in the case of peptic ulcer remains to be elucidated. The development of safe, non-invasive diagnostic tests suitable for population studies greatly facilitates this investigative process. This article presents a brief review of currently available methods of diagnosing C pylori colonization in the stomach and discusses their possible application in the field of clinical gastroenterology.

The gnotobiotic piglet as a model for the pathogenesis of Campylobacter jejuni infection

The pathogenesis of enteric changes was studied in gnotobiotic piglets which, after hysterectomy had been infected orally with Campylobacter jejuni on the first day of their life. The involvement of the entire large intestine became clinically manifest by scouring on days post infection (DPI) 4 to DPI 5, and pathomorphologically, by simultaneous inflammation and severe edema of the intestinal wall. Histology and SEM revealed inflammatory edema with abundant neutrophils, microulcerations, focal propagation and activation of goblet cells, and a presence of mucin-positive material within the intestinal lumen. TEM examination revealed disconnected interdigitating folds and wide dilated intercellular spaces between enterocytes. The endothelial cells of small blood vessels in the lamina propria showed hypertrophy with increase in the thickness of their basal lamina. Ultrastructural lesions of the large intestinal microcirculation also support the hypothesis that disturbances in the vascular system are responsible for edema in the cecum and colon. Gnotobiotic piglets may be used as a suitable animal model to study colitis induced by C. jejuni.

Rapid diagnostic test of Campylobacter pylori infection in patients of gastritis, duodenal ulcer and gastric ulcer. A study of 100 cases

Campylobacter pylori has been cultured from 85-90% of antral biopsies of patients of gastritis, duodenal ulcer and gastric ulcer at different centres in the world. It has been now firmly implicated in the aetiology of active gastritis as well as suspected to cause repeated recurrences of peptic ulcers. However, the organism is very fastidious and is difficult to grow by standard culture methods as a result of which low positivity is often obtained even in well equipped centres. The rapid biopsy urease test for the diagnosis of C pylori infection, in which the biopsy is directly cultured in a solid medium containing urea, is a very simple test. A change in colour indicates the growth of the organism. This test is 100% specific and 98% sensitive. We performed this test in 100 patients; 93 of gastritis, 6 of DU and 1 of GU during a three month period. 87 of 93 cases of gastritis (90%) and all 6 cases of DU (100%) were positive. The single case of gastric ulcer was negative. Treatment of C pylori positive cases showed that they responded poorly to 4 weeks therapy with tinidazole; 33% were cured after 2 weeks of 1.5 g amoxycillin daily, but all responded when the therapy was continued for 4 weeks.

Campylobacter pylori in alcoholic hemorrhagic "gastritis"

Previously we have shown that alcohol-associated subepithelial hemorrhages histologically represent localized superficial mucosal hemorrhage, with edema in the surrounding mucosa. We studied the relationship between Campylobacter pylori (CP) and histology in gastric subepithelial hemorrhages from 20 actively drinking alcoholic patients. Biopsies of the hemorrhagic lesions and adjacent mucosa 1 and 3 cm away were taken with a "jumbo" forceps. Biopsy slides were coded and randomized before histologic scoring and examination for CP. CP was present in 15/20 (75%) biopsies of subepithelial hemorrhages and in 32/40 (80%) biopsies from surrounding mucosa. The mean hemorrhage score was not significantly different in biopsies of subepithelial hemorrhages with and without CP (2.7 +/- 0.4 vs 3.2 +/- 0.4) and the edema scores in adjacent, nonhemorrhagic mucosa were similar in specimens with and without CP (2.0 +/- 0.3 vs 1.6 +/- 0.5). The inflammatory cell density was significantly greater in CP-positive biopsies than in CP-negative specimens (2.0 +/- 0.2 vs 0.5 +/- 0.2, P less than 0.05) with the mononuclear cell and neutrophil scores contributing equally to the overall inflammatory cell score. Almost a quarter of CP-positive specimens (11/47) had no inflammation. The mean score for lining epithelial abnormalities was also significantly higher in biopsy specimens positive for CP (1.7 +/- 0.2 vs 0.5 +/- 0.3, P less than 0.05). In conclusion, CP is present in 75% of alcohol-associated subepithelial hemorrhages, but its prevalence is similar in adjacent, nonhemorrhagic mucosa. No relationship exists between the presence of CP and the characteristic histologic abnormalities of these subepithelial hemorrhages.(ABSTRACT TRUNCATED AT 250 WORDS)

Early lesions of proliferative enteritis in pigs and hamsters

Gnotobiotic pigs and conventional hamsters were given suspensions of intestinal mucosa from a pig with proliferative hemorrhagic enteropathy and killed 10 or 21 days later. Affected animals had evidence of marked proliferation of immature enterocytes in the intestinal crypts. Numerous Campylobacter-like organisms were in the cytoplasm of enterocytes, and in some instances, bacteria were closely associated with enterocytes. Some intracellular bacteria lying below the microvillous border were within membrane-bound structures. Immunofluorescence and electron immunogold staining with specific antibodies indicated that these organisms were antigenically different from curved bacteria in the crypt lumen of early lesions. This study indicates that the life cycle of the intracellular organisms may involve entry into crypt enterocytes from the intestinal lumen with subsequent intracellular multiplication.

Experimental Campylobacter jejuni infection in Macaca nemestrina

Experimental infection of four specific-pathogen-free Macaca nemestrina monkeys (aged 3.5 and 4.5 months) with Campylobacter jejuni 81-176 caused acute diarrheal illness, characterized by fluid diarrhea, bloody stools, and fecal leukocytes, which lasted for approximately 7 to 11 days. Histologic examination of intestinal biopsies showed acute colitis characterized by infiltration of the mucosa with neutrophils and lymphocytes, and cryptitis. There were no histologic changes in the small intestine. Excretion of C. jejuni was demonstrated for 2 to 4 weeks postchallenge. Plasma antibodies to C. jejuni group antigen were elevated after challenge. Only mild diarrhea occurred after rechallenge with the same strain or with a heterologous C. jejuni strain (79-168) followed by further elevation in specific immunoglobulins A, M, and G. Four 1-year-old juvenile M. nemestrina monkeys which had experienced multiple infections with Campylobacter spp. did not exhibit illness when challenged with C. jejuni 81-176. All had elevated immunoglobulin A, M, and G plasma antibodies prior to challenge, and these humoral antibody levels were indicative of the immunity to challenge. The results demonstrate that C. jejuni infection in M. nemestrina caused colitis with clinical and pathologic results similar to those found in humans and indicate that prior infection protects against subsequent challenge.

Gastric metaplasia and Campylobacter pylori infection of duodenum in patients with chronic renal failure

Duodenal biopsy specimens from 80 patients with chronic renal failure, who were undergoing haemodialysis, were examined by light microscopy for evidence of inflammation, gastric metaplasia, and Campylobacter pylori infection. Chronic duodenitis was present in 47 (59%) of patients, of whom only seven (9%) showed evidence of active inflammation. Gastric metaplasia was present in 50 (62.5%) of patients, yet Campylobacter pylori was identified in only two patients (2.5%). It is suggested that the duodenal environment of patients with chronic renal failure remains hostile to the growth of these organisms in spite of the presence of gastric metaplasia.

Isolation of Campylobacter pyloridis from Nigerian patients with gastroduodenal pathology

Recent reports have indicated that Campylobacter pyloridis may be a causative factor in upper digestive pathology. Gastric and duodenal biopies were taken from 144 patients undergoing upper digestive endoscopy as part of investigation for dyspeptic symptoms at the Endoscopy Unit of Lagos University Teaching Hospital between October, 1985 and November, 1986 employing ACMI gastroduodenoscope model TX-7. The first 50 specimens were placed in 3 ml of Brain Heart infusion and taken to the Microbiology Laboratory of the Teaching Hospital within 1 hour. The liquid culture medium with specimens were incubated for 5 days in a candle jar at 37 degrees C, after which a loopful of the liquid culture medium was streaked onto blood agar plates and incubated under the same conditions for another 5 days. The Gram staining of two biopsy smears from the last 85 specimens showed Gram negative spiral shaped organisms. These last 85 specimens were plated on chocolate agar. All plates were incubated at 37 degrees C in a candle jar. Two (2.35%) out of the 85 specimens were positive Campylobacter pyloridis. The positive strains were Gram negative and were spiral' shaped. They were oxidase and catalase positive. The strains produced DNase and hydrolysed urea in Christensen's medium. They did not hydrolyse hippurate and were resistant to nalidixic acid but sensitive to cephalothin discs. Our findings of two positive out of 85 plated would suggest that this microorganism may not be a major contributor to the development of gastritis in Nigerians.

Campylobacter pylori: associations with antral and fundic mucosal histology and diagnosis by serology in patients with upper gastrointestinal symptoms

We obtained a sample of serum and mucosal biopsies from the antrum and usually from the corpus of the stomach from 35 symptomatic patients during routine endoscopy to analyze for the relationship between Campylobacter pylori infection, inflammation, and the diagnostic utility of a C. pylori IgG antibody assay. C. pylori was identified prospectively by culture and/or silver stain in gastric biopsies from 24 patients, and the antibody was detected in 19 (79%) of these patients. The antibody assay was positive in three other patients, two of whom had C. pylori, on reexamination of their biopsies. The accuracy of the antibody assay was 83%. Inflammation was detected in all C. pylori-positive antral biopsies (N = 19). However, five (71%) of seven antral biopsies from patients in whom all tests were C. pylori negative, also had inflammation, constituting 17% of all patients with antral gastritis (N = 30). Both antral and fundic mucosa were obtained from 26 patients and, in this group, C. pylori was detected in fundic mucosa from all patients in whom the organism also was present in the antrum (N = 15). In significant (p less than 0.001) contrast to C. pylori-positive antral histology, fundic mucosal histology was normal in 6 (40%) of 15 C. pylori-positive biopsies, all from patients with peptic ulcer disease. We conclude that C. pylori antibody assays will be useful for epidemiological studies and initial screening of the C. pylori status of individual patients. In addition, there is a high concordance rate between antral and fundic mucosa for the prevalence of C. pylori, but in contrast to the probable etiological role of C. pylori in antral gastritis, the organism appears to be only a commensal of fundic mucosa. Moreover, C. pylori infection is not evident in all patients with type B gastritis.

[Clinico-endoscopic and morphologic characteristics of patients with Campylobacter infection]

Bacteriological examination of feces of 120 patients with signs of acute gastroenterocolitis revealed C. jejuni infection in 19 (7 per cent) of them. There was a certain difference between the clinical course of C. jejuni infection and acute dysentery. The endoscopic examination of the large intestine in jejuni infection demonstrated acute hemorrhagic or catarrhal colitis and phenomena of acute exudative inflammation were found during histomorphological study. C. jejuni infection can be diagnosed on the basis of the clinico-epidemiological findings and the results of bacteriological examination of the patients' feces.

Systemic spread of Campylobacter jejuni after intravenous infections

Mice were infected intravenously with Campylobacter jejuni in order to study systemic translocation of this vibrio, as well as the interactions between bacteria and the host's defense mechanisms. It was found that granulocytes phagocyte C. jejuni in the bloodstream and that phagocytosis could be stimulated with LPS-pretreatment or, less effectively, opsonizing antibodies. It could also be demonstrated that these circulating 'infected' granulocytes are eliminated from the bloodstream mostly by the hepatic Kupffer's cells and that virulent strains of C. jejuni persist in the liver up to thirty days. It has to be concluded that phagocytosis by granulocytes and clearance of C. jejuni from the bloodstream by the liver represent important defense mechanisms in systemic Campylobacter infections.

Campylobacter pylori virulence factors in gnotobiotic piglets

Thirty-three gnotobiotic piglets from four litters were challenged with motile and nonmotile strains of Campylobacter pylori. The most motile strain, 26695, was the most virulent, with a 100% infection rate. The least motile strain, Tx30a, was the least virulent, with an infection rate of only 17%. Strain 60190 was weakly motile and had intermediate virulence, with an infection rate of 40%. Strains recovered from piglets were more motile than the challenge strains. The challenge strains also differed in cytotoxin production. The least virulent strain, Tx30a, was nontoxigenic, while the other two strains produced high levels of cytotoxin. Thus, virulence of C. pylori for gnotobiotic piglets correlated very well with motility and not as well with cytotoxin production.

[Campylobacter pylori and gastritis--the density of colonization and degree of inflammation. A semiquantitative and morphometric study]

Gastric biopsies of 1000 patients were grouped according to their diagnoses, special interest was devoted to type B-gastritis. Density of Campylobacter pylori colonization was determined semiquantitatively after Warthin-Starry silver impregnation. Bacteria could never be seen in normal mucosa. In B-gastritis statistics proved a significant correlation between bacterial colonization density and degree of inflammation. In 60 selected cases this close interrelation could be objectified by morphometry. The larger the quantity of bacteria per biopsy area the greater must be its deleterious effect on the mucus layer and the superficial epithelium. Active, chronic gastritis is characteristic of Campylobacter pylori colonisation. There can be no doubt that Campylobacter pylori plays a decisive role concerning the aetiology of type B-gastritis.

Scanning electron microscopy in the study of Campylobacter pylori associated gastritis

The close association between Campylobacter pylori (CP), gastritis and peptic ulcer is now well established. Moreover increasing evidence has been collected of a major etiological role of CP in type B chronic gastritis. For this reason, searching for CP is essential in all patients with upper gastrointestinal symptoms. Scanning electron microscopy (SEM) is a most reliable technique for studying the distribution of microorganisms and their relationship to the gastric mucosal surface. The aim of this paper is to compare SEM to other routine methods of detection for CP, such as Giemsa staining on histological sections and Urease Microtiter Test (MT) on fresh tissue and to investigate the surface morphology of gastric mucosa colonized by CP and to correlate it with the histopathological picture. Thirty-seven biopsies taken from the gastric body and the antrum of 22 patients were used for each type of determination. The different parameters were graded semiquantitatively. Histology showed a normal mucosa in 4 cases, chronic superficial gastritis in 12 and chronic atrophic gastritis in 21 cases. SEM was more sensitive than histology and Urease MT in detecting Campylobacter pylori. This is due to the patchy distribution of this bacterium on gastric mucosa. For this reason SEM should always be performed when routine tests are negative. The presence of CP correlated significantly (p less than 0.001, Spearman Rank Correlation Test) with the neutrophilic infiltrate, thus with the "activity" of the gastritis. The CP associated gastritis has no distinctive surface features other than the presence of the bacterium. SEM morphology of surface gastric mucous cells suggests that CP does not damage the lining epithelium directly. Neutrophils and inflammatory mediators could be involved in the production of the mucosal lesions.