Hunt for the origin of allergy - comparing the Finnish and Russian Karelia.

The Finnish and Russian Karelia are adjacent areas in northern Europe, socio-economically distinct but geoclimatically similar. The Karelia Allergy Study was commenced in 1998 to characterize the allergy profiles in the two areas. Allergy prevalence had increased in Finland since the early 1960s, but the situation in Russia was unknown. The key finding was that allergic symptoms and diseases were systematically more common in Finnish children and adults than in their Russian counterparts. For example, in the early 2000s, hay fever in school children was almost non-existent in Russian Karelia, and only 2% were sensitized to birch pollen compared with 27% in Finnish Karelia. Adult birth cohorts showed that among those born in the 1940s, the sensitization to pollens and pets was at the same low level in both countries, but among younger generation born in the late 1970s, the difference was already manifold. Seropositivity to some pathogens, microbial content in house dust and drinking water seemed to confer allergy protection in Russia. In subsequent studies, it became apparent that on the Finnish side, healthy children had a more biodiverse living environment as well as greater diversity of certain bacterial classes on their skin than atopic children. Abundance of skin commensals, especially Acinetobacter (gammaproteobacteria), associated with anti-inflammatory gene expression in blood leucocytes. In vivo experiments with the mouse model demonstrated that intradermally applied Acinetobacter protected against atopic sensitization and lung inflammation. These observations support the notion that the epidemic of allergy and asthma results from reduced exposure to natural environments with rich microbiota, changed diet and sedentary lifestyle. Genetic studies have confirmed strong influence of lifestyle and environment. With our results from the Karelia study, a 10-year National Allergy Programme was started in 2008 to combat the epidemic in Finland.

Allergy gap between Finnish and Russian Karelia on increase.

BACKGROUND: Multinational time-trend analyses of atopic disease have shown that the East-West gradients in prevalence are shrinking. We set out to clarify whether the disparities in the occurrence of atopy and atopic diseases in Finnish and Russian Karelia during the past 10 years have diminished and how the prevalence of atopy has evolved with successive years of birth. METHODS: Two surveys with identical methodology were performed in 1997/1998 and 2007. The study population comprised randomly selected adults, aged 25-54 years, from Finnish and Russian Karelia. Serum samples were collected for total and specific IgE measurements. Clinical data were obtained by questionnaires. RESULTS: Sensitization rates to birch pollen increased from 7.8% to 14.8% (P < 0.001) and to cat from 6.1% to 10.8% (P < 0.001) in Finland. In Russia, no significant increase was found. Contrary to this, total IgE remained stable in Finland but decreased significantly (P < 0.001) in Russia. Analyses based on years of birth revealed that the prevalence of sensitization to allergens increased with successive birth years in Finland, but remained stable in Russia. Over the 10 years, self-reported physician-diagnosed asthma increased from 5.5% to 8.1% (P = 0.05) and hay fever from 8.1% to 13.2% (P < 0.001) in Finland. CONCLUSIONS: Disparities in the prevalence of atopy and atopic disease between Finnish and Russian Karelia have further grown. The 'allergy epidemic' continues in Finland and is mainly attributable to the years of birth effect shown in atopy prevalence. In Russia, no signs of the epidemic are discernible, although the decrease in total IgE may indicate a change in environmental exposure.

A disparity in the association of asthma, rhinitis, and eczema with allergen-specific IgE between Finnish and Russian Karelia.

BACKGROUND: A substantial variation in the association of asthma, rhinitis and eczema with elevated serum allergen-specific immunoglobulin E (sIgE) levels between different populations has been reported. Here, we wanted to clarify whether these proportions are different in Finnish and Russian Karelia, and compared the ability of questionnaires, skin prick tests (SPT) and sIgE measurements to detect atopic conditions in these adjacent areas with different living conditions. METHODS: Randomly selected schoolchildren, aged 6-16 years, and their mothers from Finland (n = 344 children, 344 mothers) and Russia (427 and 284 respectively) participated. SPTs and sIgE measurements to common inhalant and food allergens were performed. The occurrence of asthma, rhinitis, eczema and related symptoms was assessed with an International Study of Asthma and Allergies in Childhood-based questionnaire. Correlation between SPT and sIgE was estimated using the Spearman correlation coefficient. RESULTS: The rate of positive sIgE results was significantly higher in Finland among both mothers and children. Seventy-seven per cent of Finnish children and 43% of Russian children with asthma were sIgE positive. The respective figures for hay fever were 94% and 67%, and for eczema 68% and 41%. This discrepancy was similar but of lower magnitude among mothers. The overall occurrence of asthma, rhinitis and eczema was very low in Russian Karelia. The correlation between SPT and sIgE results was generally good. CONCLUSION: Asthma, rhinitis and eczema in Russian Karelia are not only rare but also, to a large extent, have no sIgE component. Therefore, the ability of questionnaires to detect sIgE-mediated atopic conditions in this area of Russia is poor.

Change in the pattern of IgE reactivity to timothy grass and birch pollen allergens over a 20-year period.

BACKGROUND: Several studies have shown that the prevalence of allergy and allergen sensitization has increased in recent years. However, the changes in the pattern of IgE reactivity to individual allergens are mostly unknown. OBJECTIVE: The aim of this preliminary study was to assess the change in IgE reactivity profile to individual timothy grass and/or birch pollen allergens in sera from sensitized individuals randomly collected 20 years apart. METHODS: Serum samples from 51 sensitized individuals were obtained from 2 cross-sectional surveys performed in 1973 and 1994 using random samples from Vammala, Finland. The sera were analyzed for IgE reactivity to timothy grass and/or birch pollen extracts, recombinant (r)Phl p 1, 2, 5, 6, 7, 11, 12, native (n)Phl p 4, and rBet v 1, 2 and 4 by immunoassay (ImmunoCAP). RESULTS: The median (range) concentrations of IgE antibodies to timothy grass and birch pollen were higher in 1994 than in 1973 (6.47 [0.35 to >100] kU A/L vs 1.53 [0.40-25.3] kU A/L; P=.0035). The prevalence of IgE reactivity to some allergens was higher in 1994 than in 1973, particularly rPhl p 5 (52% vs 19%), rPhl p 6 (43% vs 12%), and rBet v 1 (100% vs 29%). There was a correlation between timothy grass pollen-specific serum IgE levels and the numbers of IgE reactivities to individual allergens (p=0.76, P<.001). CONCLUSIONS: The increase in specific IgE levels together with a possible increase in the prevalence of IgE reactivity to the major allergens Phl p 5 and Bet v 1 between 1973 and 1994 may have contributed to the increase in atopic conditions in Finland.

IgA antibodies in persisting Helicobacter pylori infection in Finnish adults.

Most individuals infected with Helicobacter pylori have elevated levels of specific IgG antibodies, but only in about two-thirds of cases does the IgA titre exceed the cut-off level. The aim of this study was to determine whether H. pylori-infected subjects with elevated IgG levels would subsequently produce IgA antibodies, and whether elevated IgA levels increased during infection. Paired sera were available from 336 adults who took part in a large population-based health survey in 1977-1980 and a follow-up study on asthma and atopic diseases in 1997-1998 (series A). Data on paired sera from 224 adults who participated in a population-based health survey in Vammala, Finland in 1973 and who gave a follow-up blood sample in 1994 (series B) were also re-analysed. H. pylori IgG and IgA levels were determined with commercially available (series A) and in-house (series B) enzyme immunoassays. Twenty-one (35%) of the 60 subjects who initially had elevated levels of IgG antibodies only were found to be IgA-positive at follow-up. In those subjects whose baseline and follow-up samples were IgG- and IgA-positive, the median IgA levels increased by 48% and 22% in series A and B (p < 0.0001 and p 0.0241), respectively, whereas the median IgG levels did not change significantly in either series. During H. pylori infection, an increase in specific IgA was reflected by the increase in the number of responders and by the rise in titres.

Normal serum pepsinogen I levels in adults: a population-based study with special reference to Helicobacter pylori infection and parietal cell antibodies.

OBJECTIVE: Low serum pepsinogen I (PG I) values are common in subjects with advanced corpus atrophy with or without parietal cell antibodies (PCA). Elevated values are usual during Helicobacter pylori infection. MATERIAL AND METHODS: PG I levels were determined in two randomly selected cross-sectional adult population samples using the Gastroset PGI test kits. The sera (408 in 1973 and 504 in 1994), tested earlier for H. pylori infection and now for PCA, represented subjects living in Vammala, Finland. RESULTS: In the PCA-negative population, the mean (+/-SD) PG I level was significantly higher in men than in women among both H. pylori-negative (88.13+/-34.16 microg/l versus 72.43+/-29.31 microg/l; p<0.0001) and H. pylori-positive (110.50+/-50.59 microg/l, versus 97.74+/-44.82 microg/l, p<0.0001) subjects; the difference between all H. pylori-positive and -negative subjects was also significant (p<0.001). In the 10-year age groups, age had no impact on the mean PG I levels in H. pylori-negative subjects (p=0.860). In the PCA-positive population, the 10 H. pylori-positive subjects had higher mean PG I levels (112.96+/-53.62 microg/l) than the 13 H. pylori-negative subjects (32.57+/-27.59 microg/l; p=0.002); the latter mean was also significantly lower than that of the PCA- and H. pylori-negative subjects (80.08+/-32.69 microg/l; p<0.0001). CONCLUSIONS: Men had higher normal PG I values than women, but there was no significant variation by age. H. pylori infection was associated with elevated PG I levels and a small decrease with increasing age. Non-infected PCA-positive subjects showed the lowest mean PG I level.

Genetic and environmental factors in the immunopathogenesis of atopy: interaction of Helicobacter pylori infection and IL4 genetics.

BACKGROUND: Both genetic and environmental factors, e.g. early childhood infections, have a role in the pathogenesis of atopic diseases. OBJECTIVE: To examine simultaneously the strength and possible interactions of two known such factors, IL4 genetics and Helicobacter pylori infection, on the risk of atopy and asthma. METHODS: Gene polymorphism analyses and skin prick tests (SPT) were determined in 245 adult asthmatics and 405 nonasthmatic controls of population-based case-control study. SPTs were used as an indicator of atopy. H. pylori infection was verified by detecting anti-H. pylori IgG antibodies in sera. RESULTS: A significant negative association was seen between the presence H. pylori antibodies and SPT positivity (> or =1 positive reactions) in both asthmatics and controls (p = 0.002 and p = 0.025, respectively) but the effect of IL-4 polymorphism (SNP -590C/T) was nonsignificant in both groups (p = 0.071 and p = 0.072, respectively). However, IL4 genetics had an effect on susceptibility to H. pylori: asthmatics carrying the IL4 -590 allele T had a diminished risk to be H. pylori infected (OR 0.485 95%CI 0.287-0.819). This effect was not seen in controls. Logistic regression analysis indicated that H. pylori and IL4 effects on atopy risk are not interdependent. CONCLUSIONS: This study showed that the effect of H. pylori infection on atopy risk is stronger than that of IL4 genetics. There is no interaction between these factors on the pathogenesis of atopy suggesting that these factors have distinct immunopathogenetic mechanisms. However, the genetic effect may modify the role of infective agents by effecting on susceptibility to disease.

Age-dependent accuracy of Helicobacter pylori antibody assays for adults, with special emphasis on atrophic gastritis.

The accuracy of Helicobacter pylori antibody assays for 561 consecutive adult outpatients who had undergone gastroscopy was studied. The sensitivity of an immunoglobulin G test was 99 to 100% for all age groups, but the specificity declined by age group, from 99% for those aged 15 to 49 years to 75% for those aged > or =65 years. The exclusion of false-positive results for patients with atrophic gastritis improved the specificity to 93 to 97% for the older age groups.

Cost-benefit analysis of Helicobacter pylori screening.

BACKGROUND: Helicobacter pylori screening may markedly reduce mortality and morbidity in the decades ahead. AIMS: This study explores the costs and benefits of population-based H. pylori screening in terms of health care cost taking into account all relevant H. pylori-related diseases. MATERIAL AND METHODS: The computer-based decision analysis compared two strategies: (1) screen for H. pylori and treat those individuals who test positive, and (2) do not screen for H. pylori, and test and treat H. pylori only if related clinical symptoms appear. The model estimated the discounted H. pylori-related accumulative health care costs from screening age to death in both strategies. The baseline case estimates cost-benefit for screenees aged 15-45 years. The main outcome measure is the incremental health care cost per case in the screening compared with the no-screening alternative. The probability estimates were obtained from the Finnish Vammala H. pylori screen and treat project, including 5288 subjects in the years 1996-1998, published studies, national statistics and hospitals' internal accounts. RESULTS: The incremental cost per case was 26 US dollars in the screening compared with the no-screening alternative. It was lowest in the group aged 45 years, where H. pylori screening showed cost savings per case. CONCLUSIONS: H. pylori screening is more favourable in the older age cohorts. The estimated cost per screenee can be considered to be very acceptable if the current pathophysiological evidence on the potential effects of H. pylori eradication are confirmed in the future. However, there is uncertainty about the possible negative effect of eradicating H. pylori infection on gastro-esophageal reflux disease and esophageal adenocarcinoma. This could change the balance of benefits against risks of eradicating H. pylori infection.

Increase of allergen-specific immunoglobulin E antibodies from 1973 to 1994 in a Finnish population and a possible relationship to Helicobacter pylori infections.

BACKGROUND: The prevalence of atopic diseases--hayfever, asthma and eczema--has increased over the past decades. The increase may be associated with decreased rates of infections such as measles, hepatitis A, tuberculosis, toxoplasmosis, and, as recently suggested, Helicobacter pylori gastritis. OBJECTIVE: Since the increase of atopy has been mainly based on clinical studies, we wanted to study the prevalence of allergen-specific Immunoglobulin (Ig)E antibodies in two cross-sectional, adult population-based serum samples two decades apart. Since the sera had been tested for H. pylori antibodies, we also had a chance to look for a possible relationship between these two findings. METHODS: We determined the prevalence rate of allergen-specific serum IgE antibodies against birch and timothy pollen, and cat and dog epithelium allergens by the radioallergosorbent test in a 15-54-years-old Finnish population using 326 sera collected in 1973 and 319 sera collected in 1994 from randomly selected subjects. RESULTS: From 1973 to 1994 allergen-specific IgE prevalence rates and IgE antibody levels rose. In 1994, the prevalence rate of positive findings in 15-24-year-old population had increased from 11 to 38% (3.5-fold increase, P = 0.0001, OR 5.12, CI 95% 2.32-11.3). In older 10-year age groups similar trends did not reach significance, but the overall change was significant with all three cut-off levels of allergen-specific IgE analysed. The percentage of IgE-positive persons rose mainly in the subgroup with no H. pylori antibodies. In 1994 21% of the H. pylori-negative subjects had IgE antibodies compared with 5% of the H. pylori-positive subjects (in 1973 11% in both subgroups). CONCLUSIONS: IgE-based evidence for an increase in IgE-mediated allergy was uncovered. The increase occurred mainly in the subgroup with no antibodies to H. pylori, which support the hypothesis that H. pylori could be one of the microbes counteracting atopy.

The effect of Helicobacter pylori eradication on the natural course of atrophic gastritis with dysplasia.

BACKGROUND: There are few data on the natural course of Helicobacter pylori-related atrophic gastritis. AIM: To investigate the effect of H. pylori eradication on advanced atrophic gastritis in the corpus. METHODS: Twenty-two elderly men with H. pylori infection and moderate or severe atrophic corpus gastritis formed the study population. These men were under endoscopic surveillance because of the presence of indefinite or definite dysplastic gastric lesions in addition to atrophic corpus gastritis. The men were gastroscopically and bioptically examined four times before they received H. pylori eradication therapy (mean follow-up time, 7.5 years), and once again 2.5 years after eradication therapy. Serum levels of pepsinogen I and H. pylori antibodies were analysed at baseline, immediately before and 2.5 years after eradication therapy. RESULTS: During the 7.5-year period prior to eradication therapy, no significant changes were observed in the mean atrophy and intestinal metaplasia scores or in the mean serum level of pepsinogen I. However, a significant improvement occurred in the mean histological scores of inflammation (from 2.2 to 0.5), atrophy (from 2.2 to 1.2) and intestinal metaplasia (from 1.6 to 1.1) in the corpus mucosa after H. pylori eradication. In addition, the mean serum level of pepsinogen I increased from 16.3 to 25.7 microg/L (P=0.0071, Wilcoxon signed rank test) after eradication therapy. CONCLUSIONS: The results suggest that advanced atrophic corpus gastritis (and intestinal metaplasia) improves and may even heal after the eradication of H. pylori.

Evidence that cagA(+) Helicobacter pylori strains are disappearing more rapidly than cagA(-) strains.

BACKGROUND AND AIMS: The prevalence of Helicobacter pylori colonisation in populations in developed country has been declining, as shown by community based serological surveys of adults in Vammala, Finland in 1973 and 1994. In this study, we determined whether the proportion of subjects colonised by cagA(+) or cagA(-) H pylori strains has changed as the overall prevalence of H pylori(+) has declined. METHODS: We examined 911 sera from Vammala's study for antibodies to the CagA antigen of H pylori using a truncated CagA protein as the antigen in an ELISA and we examined the trend in acquisition and carriage of cagA(+) strains. RESULTS: As expected, the prevalence of carriage of both cagA(+) and cagA(-) strains fell between 1973 and 1994 (p<0.001). However, the prevalence of cagA(+) strains among those <45 years declined (34% to 8%) significantly (p<0.001) more than for cagA(-) strains (12% to 6%). Of 221 subjects with paired serum samples, 12 (5.4%) changed H pylori status; the estimated seroconversion and reversion rates were 0.4% and 0.13% per year, respectively. Except for the few individuals who changed serostatus, absolute antibody levels to H pylori antigens, including CagA, changed little over the 21 year period. CONCLUSIONS: The decline in CagA seroprevalence predominantly reflects declining acquisition of cag(+) strains in younger subjects. In addition, these data confirm that H pylori acquisition chiefly occurs during childhood but continues to occur during adulthood, albeit at low rates, in developed countries.

Decreasing prevalence of helicobacter antibodies in Finland, with reference to the decreasing incidence of gastric cancer.

Time trends and geographical variation of Helicobacter pylori antibodies in Finland were investigated by enzyme immunoassay in 20- to 34-year-old randomly selected females from six localities during 1969-73 (n = 375), and 15- to 45-year-old females representing nine communities and four geographical areas in 1983 (n = 882) and 1995 (n = 842). In the six communities investigated at three different time points, the overall prevalence declined from 38 to 12%, with an emphasis on the latter 12 years. The regionally varying rate of decrease in helicobacter prevalence changed the pre-existing geographical variation, leaving northern Finland with the highest rate. A 10%-units higher local helicobacter prevalence seemed to predict a 23% (95% CI 3-44%) higher gastric cancer incidence 20 years later. The overall decline in helicobacter seropositivity is consistent with earlier reports from Finland and other developed countries, and supports the cohort theory as an explanation for the age-related increase in H. pylori seroprevalence.

Development of an immunoassay for rapid detection of ganglioside GM(1) mimicry in Campylobacter jejuni strains.

Mimicry of peripheral nerve gangliosides by Campylobacter jejuni lipopolysaccharides (LPSs) has been proposed to induce cross-reacting antiganglioside antibodies in Guillain-Barré syndrome (GBS). Because current methods for LPS characterization are labor-intensive and inhibit the screening of large numbers of strains, a rapid GM(1) epitope screening assay was developed. Biomass from two agar plates of confluent growth yielded sufficient LPS using a novel phenol-water and ether extraction procedure. Extracts of LPS were reacted with cholera toxin (GM(1) ligand), peanut agglutinin (Gal beta1-->3GalNAc ligand), and anti-GM(1) antibodies. After the assay was validated, 12 of 59 (20%) C. jejuni serostrains, including four serotypes that have not previously been associated with GBS, reacted with two or more anti-GM(1) ganglioside reagents. Subsequently, LPS extracts from 5 of 7 (71%) C. jejuni isolates and 2 of 3 (67%) C. jejuni culture collection strains bore GM(1) structures. Overall, the assay system was reliable, efficient, and reproducible and may be adapted for large-scale epidemiological studies.

Cure of Helicobacter pylori infection after failed primary treatment: one-center results from 120 patients.

BACKGROUND: Treatment with a proton pump inhibitor (PPI) and antimicrobials cures Helicobacter pylori infection in about 90% of patients. This is a retrospective overview of our studies aiming to cure the infection in all compliant patients with failed initial therapy. METHODS: We retreated 120 (19% of 644) H. pylori-infected patients whose initial therapy had failed. The retreatments included (i) triple therapy (TT): colloidal bismuth subcitrate, metronidazole, amoxicillin (or tetracycline); (ii) quadruple therapy (QT): TT and a PPI; or (iii) high doses of both a PPI and clarithromycin combined with a further 1-3 individually selected antimicrobials. The eradication results were determined after 6-12 months. RESULTS: The 1st retreatment was successful in 70 of 120 patients. The 2nd retreatment cured 25 of the remaining 42 patients, the 3rd 13 of 17, and the 4th the last 4 patients. The cumulative eradication rate (ITT) was 93% (95% CI: 88.9%-97.9%; 8 patients withdrew after a failed 1st retreatment) and the rate was 100% in the remaining 112 patients who accepted several retreatments. The 1st retreatment with TT cured 23% (95% CI: 12%-34%) of 57 patients and QT 85% (95% CI: 74%-96%) of 41 patients who had initially undergone a failed metronidazole-based treatment. All retreatments were well tolerated. CONCLUSIONS: In this study, high doses of a PPI and clarithromycin combined with 1-3 antimicrobials according to susceptibility data proved to be the best drug combination in the cure of H. pylori infection after failed primary treatment. Giving imidazole- and bismuth-based QT (without clarithromycin) as the first-line treatment of H. pylori infection ensures that the number of failures remains low.

Diagnosis of Helicobacter pylori infection in patients with atrophic gastritis: comparison of histology, 13C-urea breath test, and serology.

BACKGROUND: Atrophic gastritis, a risk factor for gastric cancer, is a late consequence of Helicobacter pylori infection in approximately one-third of the infected patients. It has been suggested that gastric cancer would develop less frequently if H. pylori were eradicated. However, the prevalence of H. pylori infection may be underestimated in patients with atrophic gastritis and intestinal metaplasia if only biopsy-based diagnostic methods are used. METHODS: We compared histology, 13C-urea breath test (13C-UBT), and serology in H. pylori diagnostics in 50 male patients with atrophic corpus gastritis. RESULTS: H. pylori was detected in 15 (30%) patients by histology and in 14 (28%) by 13C-UBT, whereas increased serum antibody levels indicating H. pylori infection were found in 41 (82%) patients (P < 0.0001 between serology and both histology and 13C-UBT). H. pylori infection was associated with atrophic corpus gastritis in 84% of the present patients (in one patient with normal antibody titres H. pylori was defined histologically). CONCLUSIONS: H. pylori infection would have been missed in most patients with atrophic gastritis without the analysis of H. pylori antibodies. Therefore, in patients with atrophic gastritis, the use of serology is encouraged in diagnosing H. pylori infection.

Association of CagA-positive infection with Helicobacter pylori antibodies of IgA class.

cagA gene, the best known virulence factor of Helicobacter pylori, codes for an immunodominant CagA protein. In this study, CagA antibodies of the IgG class were measured by immunoblot or enzyme immunoassay in subjects with positive H. pylori serology, and the presence of CagA antibodies was compared with that of H. pylori antibodies of IgA and IgG classes. Serum samples were available for a total of 1,481 subjects, including gastroscopied patients with biopsy-verified H. pylori infection, smoking men with a normal or low serum pepsinogen I level indicating atrophic corpus gastritis, and subjects who later developed gastric cancer and their matched controls. CagA antibodies were significantly more prevalent among individuals with elevated H. pylori antibody titres of the IgA class than in those with IgG antibodies only, with the exception of a small subgroup of individuals who later developed gastric cancer. CagA-positive H. pylori strains seem to induce an immune response with a markedly higher frequency of IgA than what is found in inflammation caused by CagA-negative strains. The presence of serum IgA antibodies to H. pylori seems to indicate a higher risk for CagA-positive H. pylori infection and possibly more severe late sequelae of the disease.

Is Helicobacter pylori infection associated with chronic urticaria?

There have been controversial reports of an elevated prevalence rate of Helicobacter pylori infection in chronic urticaria patients. Furthermore, in some studies remission of chronic urticaria has been reported after eradication of H. pylori. The aim of this investigation was to evaluate the prevalence of H. pylori infection among chronic urticaria patients and to study the effect of eradication therapy on urticaria symptoms. Chronic urticaria patients (n=235) were enrolled and H. pylori status was determined serologically. Thirty-five patients received antimicrobial triple therapy. 25% of the patients were positive for H. pylori. The prevalence of H. pylori infection was not significantly higher among urticaria patients compared with the normal Finnish population in any of the age groups studied. Of the successfully treated patients, 27% showed remission of urticaria. Our data suggest that the prevalence of H. pylori infection is not elevated among chronic urticaria patients and that H. pylori eradication does not appear to influence the course of chronic urticaria.

Helicobacter antibodies in Finnish centenarians.

BACKGROUND: The prevalence of helicobacter antibodies increases with age and, in many developed countries, is highest in people born before 1940. Data on very old subjects are, however, limited. In this study we wanted to determine whether the age-related increase in the seroprevalence of H. pylori infection continues even in the oldest age group alive in Finland, the centenarians. METHODS: Sera from 173 subjects (93% of all centenarians alive in Finland in 1991) were available for the present study. IgG and IgA antibodies against H. pylori were determined by an in-house enzyme immunoassay. To estimate the influence of atrophic gastritis on the prevalence of helicobacter antibodies, serum pepsinogen I (PG I) concentrations and parietal cell antibodies (PCAs) were measured by an enzyme immunoassay and indirect immunofluorescence, respectively. RESULTS: The prevalence of helicobacter antibodies in Finnish centenarians was 66%. Low PG I values (<28 microg/l) were found in 36% and positive PCAs in 16% of the subjects studied. The prevalence of PCAs was especially high (50%) in H. pylori-negative subjects with low PG I values, suggesting severe gastric atrophy. CONCLUSIONS: The age-related increase in H. pylori seroprevalence did not continue in the oldest age group alive in Finland. This may be explained partly by a relatively high frequency of atrophic gastritis (as suggested by low PG I values) in H. pylori-negative centenarians, but other factors--such as selective H. pylori-related mortality--may also have contributed to the fairly low seroprevalence (66%) observed.

Persisting Helicobacter antibodies in Finnish children and adolescents between two and twenty years of age.

BACKGROUND: Helicobacter pylori is an important gastric pathogen usually acquired in childhood. The presumed lifelong progression of H. pylori infection has recently been called into question in some longitudinal studies on children. In this follow-up study the prevalence and persistence of H. pylori antibodies in Finnish children and adolescents from three communities was determined. METHODS: We measured H. pylori antibodies in follow-up serum samples of 337 Finnish children who participated in a measles-mumps-rubella vaccine study started in 1982. All available samples collected in 1983, 1987 and 1995 were studied first; additional serum samples collected yearly were studied from children who became seropositive during the follow-up period. RESULTS: The overall prevalence of H. pylori antibodies was 5.6%. About two-thirds of the Helicobacter infections were acquired before the age of 7 years; of the remaining one-third the time of seroconversion varied between 7 and 19 years. No seroreverters were found. There were no statistically significant differences in the seroprevalence of H. pylori antibodies in the three communities studied. CONCLUSIONS: The prevalence of H. pylori antibodies in Finnish children studied was low. Although the majority of new infections were found in children younger than 7 years of age, new Helicobacter infections were acquired throughout childhood and adolescence. Once acquired H. pylori infection, as verified by Helicobacter antibodies, persisted.