Evaluation of an enzyme immunoassay-based stool antigen test to detect Campylobacter jejuni and Campylobacter coli

An enzyme immunoassay-based antigen test (Ridascreen Campylobacter; R-Biopharm, Darmstadt, Germany) was evaluated for the detection of Campylobacter jejuni and Campylobacter coli in 1050 clinical stool samples as compared with culture on selective medium. After routine inoculation for Salmonella, Shigella, Yersinia, Aeromonas, Plesiomonas, and Campylobacter, the same swab specimens were used for the antigen test. The positivity rate for Campylobacter was 9.3% in culture, and the antigen test gave a sensitivity of 69%. Forty-six stool samples culture-negative for Campylobacter grew other enteropathogens; one (positive for Salmonella sp.) was positive in the antigen test. Of all the 952 Campylobacter culture-negative samples, 830 were negative in the antigen test, giving a specificity of 87%. Almost 5% of the samples showed equivocal antigen test results. If the moderate sensitivity of the antigen test was due to a low sensitivity of culture or receiving the stool samples in transportation tubes remains to be studied.     

Helicobacter pylori infection in Finland

Helicobacter pylori causes chronic gastritis worldwide and it is the most important single factor in peptic ulcer disease. Up to half of H. pylori infected individuals develop atrophic gastritis over years and decades. H. pylori infection has also been classified as a class I carcinogen in human gastric cancer. Most infections are obtained in childhood, in Finland mainly before the age of 7 years but the exact transmission routes are not known. The infection shows an age‐dependent pattern, the infection being rare among children but gradually becoming more prevalent among older age groups. As new infections are few in adults and the infection only rarely disappears without effective antimicrobial therapy, the occurrence of the infection in the old actually reflects the prevalence of the infection in their childhood. In developed countries, such as Finland, a rapid decline of H. pylori prevalence rate has been demonstrated. In order to speed up this natural decline of the infection, a unique population based ‘screen and treat’ project was started in Vammala, a semiurban south‐western community in Finland. In this survey, young inhabitants were offered diagnosis and treatment for H. pylori.     

Detection of Campylobacter in human and animal field samples in Cambodia

Campylobacter are zoonotic bacteria and a leading cause of human gastroenteritis worldwide with Campylobacter jejuni and C. coli being the most commonly detected species. The aim of this study was to detect Campylobacter in humans and livestock (chickens, ducks, pigs, cattle, water buffalo, quail, pigeons and geese) in rural households by routine culturing and multiplex PCR in faecal samples frozen before analysis. Of 681 human samples, 82 (12%) tested positive by PCR (C. jejuni in 66 samples and C. coli in 16), but none by routine culture. Children were more commonly Campylobacter positive (19%) than adult males (8%) and females (7%). Of 853 livestock samples, 106 (12%) tested positive by routine culture and 352 (41%) by PCR. Campylobacter jejuni was more frequent in chickens and ducks and C. coli in pigs. In conclusion, Campylobacter proved to be highly prevalent by PCR in children (19%), ducks (24%), chickens (56%) and pigs (72%). Routine culturing was insufficiently sensitive in detecting Campylobacter in field samples frozen before analysis. These findings suggest that PCR should be the preferred diagnostic method for detection of Campylobacter in humans and livestock where timely culture is not feasible.     

Ultrastructural study of two patterns in the interaction of Helicobacter pylori with neutrophils.

As evidenced by electron microscopy, unopsonised bacteria of some Helicobacter pylori strains were readily taken into cytoplasmic vacuoles of human neutrophils; those of other strains were only rarely absorbed. The strains engulfed like this also induced strong oxidative burst reactions in neutrophils, as measured by chemiluminescence. This has been associated with peptic ulcer disease, in the past. The ultrastructural interaction patterns agreed with the reaction patterns shown by chemiluminescence.     

Inverse correlation between Helicobacter pylori infection and inflammatory bowel disease.

AIMS: To determine the seroprevalence of Helicobacter pylori in patients with Crohn's disease or ulcerative colitis and in controls without inflammatory bowel disease (IBD). METHODS: One hundred consecutive patients with Crohn's disease, 100 consecutive patients with ulcerative colitis, and 100 age and sex matched controls were studied. Serum H pylori IgG and IgA antibody titres were measured by enzyme immunoassay. RESULTS: The seroprevalence of H pylori was 15% in patients with IBD (13% in patients with Crohn's disease and 18% in patients with ulcerative colitis), whereas the corresponding figure for the controls was 43%. When compared with controls, the seroprevalence of H pylori in patients with IBD was considerably lower in all age groups tested. There was no important difference in treatment with sulphasalazine or in any other medical therapy administered to H pylori positive and negative patients. At the time of blood sampling there was no difference in the level of education or in the employment status between the patients and the controls. CONCLUSIONS: Patients with IBD were less likely to be infected with H pylori than their age and sex matched controls. Neither medical treatment nor socioeconomic factors could explain the difference.     

Spontaneous disappearance of Helicobacter pylori antibodies in patients with advanced atrophic corpus gastritis

Background. Only a few reported studies focus on the natural history and course of advanced and severe chronic atrophic gastritis. Methods. In this study we followed 47 men (mean age 62 years) with advanced (moderate or severe) Helicobacter pylori-positive atrophic corpus gastritis. Duration of endoscopic follow-up was 6 years and follow-up based on serum levels of pepsinogen I and antibodies to H. pylori covered a period of 10 years. None of the patients was treated for H. pylori infection prior to end of follow-up. Results. The median H. pylori antibody titre declined (IgG from 4000 to 1300; IgA from 200 to 50) in the study population, and 11 men (23%) converted to seronegative (p=0.0005, Fisher's exact test). There was a small but significant (p=0.0004, Page's test) declining trend in mean atrophy score of the corpus during follow-up (from 2.5 to 2.2). However, no significant changes were observed in grade of atrophy or intestinal metaplasia of the antral mucosa or in grade of intestinal metaplasia in the corpus. The mean SPGI level remained at the initial low level during the entire follow-up. Conclusions. H. pylori antibodies disappear spontaneously within 10 years in almost one fourth of patients with advanced atrophic corpus gastritis. The disappearance of H. pylori antibodies is accompanied by no or more than a mild improvement of the gastric mucosa.     

Milk protein IgG and IgA： The association with milk-induced gastrointestinal symptoms in adults

AIM: To study the association between serum levels of milk protein IgG and IgA antibodies and milk-related gastrointestinal symptoms in adults.METHODS: Milk protein IgG and IgA antibodies were determined in serum samples of 400 subjects from five outpatient clinics in Southern Finland. Subjects were randomly selected from a total of 1900 adultsundergoing laboratory investigations in primary care. All 400 participants had completed a questionnaire onabdominal symptoms and dairy consumption while waiting for the laboratory visit. The questionnairecovered the nature and frequency of gastrointestinal problems, the provoking food items, family history and allergies. Twelve serum samples were disqualified due to insufficient amount of sera. The levels of specific milkprotein IgG and IgA were measured by using the ELISA technique. The association of the milk protein-specific antibody level was studied in relation to the milk-related gastrointestinal symptoms and dairy consumption.RESULTS: Subjects drinking milk ( n = 265) had higher levels of milk protein IgG in their sera than non-milk drinkers ( n = 123, P < 0.001). Subjects with gastrointestinal problems related to milk drinking ( n = 119) consumed less milk but had higher milk protein IgG levels than those with no milk-related gastrointestinal symptoms ( n = 198, P = 0.02). Among the symptomatic subjects, those reporting dyspeptic symptoms had lower milk protein IgG levels than non-dyspeptics ( P < 0.05). However, dyspepsia was not associated with milk drinking ( P = 0.5). The association of high milk protein IgG levels with constipation was close to the level of statistical significance. Diarrhea had no association with milk protein IgG level ( P = 0.5). With regard to minor symptoms, flatulence and bloating ( P = 0.8), were not associated with milk protein IgG level. Milk protein IgA levels did not show any association with milk drinking or abdominal symptoms. The levels of milk protein IgA and IgG declined as the age of the subjects increased ( P < 0.004).CONCLUSION: Milk protein IgG but not milk IgA seems to be associated with self-reported milk-induced gastrointestinal symptoms.     

Clonal Distribution and Virulence of Campylobacter jejuni Isolates in Blood

Campylobacter jejuni bacteria are highly diverse enteropathogens. Seventy-three C. jejuni isolates from blood collected in Finland were analyzed by multilocus sequence typing and serum resistance. Approximately half of the isolates belonged to the otherwise uncommon sequence type 677 clonal complex. Isolates of this clonal complex were more resistant than other isolates to human serum.