Association of Campylobacter pylori on the gastric mucosa with antral gastritis in children

Pediatric disorders of the stomach

Disorders of the stomach represent a significant portion of the practice of pediatric gastroenterology. Controversy still exists in the appropriate management of children with abdominal pain and vomiting and large gaps remain in our understanding of the physiology and pathophysiology of the stomach in children. Nevertheless, we have made significant progress in understanding Helicobacter pylori infection and gastric motility in the pediatric population.

Serum ferritin and Helicobacter pylori infection in children: a sero-epidemiologic study in Korea

BACKGROUND

Helicobacter pylori infection is known to affect iron metabolism and serum ferritin levels, which are reduced in adults with H. pylori infection. The aim of the present study was to investigate the association between H. pylori infection and iron status in healthy Korean children.

METHODS

The H. pylori seropositivity in 753 schoolchildren aged 6-12 years was screened for using an ELISA and confirmed by western blot analyses. Serum ferritin levels were measured using an immunoradiometric assay in 36 H. pylori-seropositive children and in 72 age- and gender-matched seronegative controls.

RESULTS

The median serum ferritin levels were significantly lower in H. pylori-seropositive children than in seronegative controls (24 vs 39 ng/mL; P < 0.001). The prevalence of iron deficiency (ferritin < 15 ng/mL) in H. pylori-seropositive children was significantly higher (13.9%) than in seronegative children (2.8%). This association persisted after adjusting for age and their socioeconomic status (odds ratio, 5.6; 95% confidence interval, 1.0-30.6).

CONCLUSION

Serum ferritin levels are reduced in children with H. pylori infection. The H. pylori infection may lead to iron deficiency in children.

Diagnostic accuracy of the 13C-urea breath test for childhood Helicobacter pylori infection: a multicenter Japanese study

OBJECTIVES

In adults, the 13C-urea breath test (UBT) has been widely used as a noninvasive test of Helicobacter pylori infection because of its high sensitivity and specificity. However, this test is less well established in pediatric practice. The optimum cutoff value and test protocol of the 13C-UBT remains to be established in the pediatric population. The primary purpose of this study was to evaluate diagnostic accuracy of the 13C-UBT for children and to determine its optimum cutoff value.

METHODS

A total of 220 Japanese children aged 2-16 yr (mean = 11.9) who underwent upper GI endoscopy and gastric biopsies were finally studied. Endoscopic diagnoses included gastritis (n = 131), gastric ulcer (n = 15), duodenal ulcer (n = 72), and combined ulcer (n = 2). H. pylori infection status was confirmed by biopsy tests including histology, urease test, and culture. With the 13C-UBT, breath samples were obtained at baseline and at 20 min after ingestion of 13C-urea without a test meal and were analyzed by isotope ratio mass spectrometry. Based on biopsy tests, a cutoff value was determined using a receiver operating characteristic curve. In 26 children (seven children infected and 19 noninfected), paired breath samples were also measured by nondispersive infrared spectometry (NDIRS).

RESULTS

Biopsy tests demonstrated that 89 children (40%) were infected with H. pylori and 131 children were not infected. There were no statistical differences in mean delta 13C values at 20 min between male and female H. pylori-infected and noninfected patients. A receiver operating characteristic analysis defined the best cutoff value as 3.5 per thousand. The overall sensitivity and specificity at a cutoff value of 3.5 per thousand were 97.8% (95% CI = 92.1-99.7%) and 98.5% (95% CI = 96.4-100%), respectively: high sensitivity and specificity were demonstrated in all three age groups (< or =5, 6-10, and > or = 11 yr). There was a close correlation between the values with isotope ratio mass spectrometry and NDIRS methods (r = 0.998, p < 0.001).

CONCLUSIONS

The 13C-UBT with a cutoff value of 3.5 per thousand is an accurate diagnostic method for active H. pylori infection. The test with the NDIRS method is inexpensive and might be widely applied in clinical practice.

Gastroduodenal lesions in polycythaemia vera: frequency and role of Helicobacter pylori

The prevalence of gastroduodenal lesions is higher in polycythaemia vera (PV) than in the general population. However, the role of Helicobacter pylori (H. pylori) in the pathogenesis of such lesions is unknown. The aim of our study was to evaluate the prevalence of gastroduodenal lesions in PV patients and dyspeptic controls, and to assess the role of PV and H. pylori infection in inducing them. Thirty-five PV patients fulfilling selection criteria and 73 age- and sex-matched controls underwent upper gastrointestinal endoscopy. Six gastric mucosal biopsies were taken in all patients and controls, and analysed for presence of H. pylori; serum anti-CagA was assayed by Western blot. Data were analysed with descriptive statistics and multivariate regression analysis. Compared with controls, PV patients showed a significantly higher frequency of erosions (46% versus 12%), ulcers (29% versus 7%), H. pylori positivity (83% versus 57%), and anti-CagA positivity (66% versus 37%). Fourteen out of 20 (70%) asymptomatic PV patients had gastroduodenal lesions. At multivariate analysis, H. pylori, presence of PV alone, and both PV and anti-CagA were significantly and strongly associated with a higher frequency of gastroduodenal lesions (P < 0.05, P < 0.01 and P < 0.05 respectively). Both PV and H. pylori infection were independent risk factors for gastroduodenal lesions; the underlying pathogenetic mechanism responsible for gastroduodenal lesions in PV possibly involves blood mucosal flow and trophism. The higher susceptibility of H. pylori infection and the high frequency of asymptomatic gastroduodenal lesions in PV patients suggest a surveillance of these patients.

Antibiotic resistance of Helicobacter pylori strains in Japanese children

The resistance of Helicobacter pylori to the recently available antibiotic treatment regimens has been a growing problem. We investigated the prevalence of H. pylori resistance to clarithromycin, metronidazole, and amoxicillin among 51 H. pylori isolates from Japanese children. In addition, the mutations of the corresponding gene were studied by PCR and restriction fragment length polymorphism analysis. Primary resistance to clarithromycin, metronidazole, and amoxicillin was detected in 29, 24, and 0% of strains, respectively. The eradication rates in clarithromycin-susceptible and -resistant strains were 89 and 56%, respectively (P < 0.05). The prevalence of strains with acquired resistance to clarithromycin (78%) was higher than that of strains with primary resistance (P < 0.01). Among the clarithromycin-resistant strains studied, 92% showed cross-resistance to azithromycin. No acquired resistance to amoxicillin was demonstrated. The A2144G mutation in the 23S rRNA gene was detected in 11 of 12 (92%) clarithromycin-resistant strains tested, whereas the mutation was not detected in any of the 15 susceptible strains. The deletion of the rdxA gene was not demonstrated in any of the strains. The results indicate that a high prevalence of clarithromycin-resistant strains is associated with eradication failure. Testing of susceptibility to clarithromycin is recommended.

Prevalence and specificity of antigastric autoantibodies in adolescents infected with Helicobacter pylori

OBJECTIVES

Antigastric autoantibodies (AGA) can be detected in as many as 50% of adults infected with Helicobacter pylori. We investigated H pylori -associated antigastric autoimmunity in children and adolescents.

STUDY DESIGN

Patients with dyspepsia (n = 78; mean age 10.9 years, range 2-21 years, SE 0.46 years) underwent gastroscopy. H pylori infection was determined by serologic and histologic features and breath tests. AGA were detected by immunohistochemistry and were characterized by immunoprecipitation with the gastric hydrogen ion, potassium ion, adenosine triphosphatase (H(+),K(+)-ATPase). In absorption assays, antibodies against H pylori were removed to determine the role of molecular mimicry.

RESULTS

AGA were detected in 9 (18%) of the 51 infected patients and in 1 (4 %) of the 27 noninfected patients (P =.08; nonsignificant) and could not be absorbed to H pylori. Children with AGA were significantly older (P =.01). AGA in H pylori gastritis reacted against the gastric H(+),K(+)-ATPase in 3 (33%) of the 9 patients.

CONCLUSIONS

The age of the patient or the duration of gastritis seem to be relevant factors for the formation of antigastric autoimmunity. The gastric H(+),K(+)-ATPase represents an autoantigen as early as childhood. No evidence for a role of molecular mimicry between H pylori and the host at this young age could be found.

Helicobacter pylori infection in children

A number of scientific breakthroughs since H pylori first became recognized as a human pathogen have increased our understanding of the pathogenesis of gastroduodenal disease. In particular, advances in molecular bacteriology and the complete sequencing of the H pylori genome in 1999, and soon thereafter the human genome, provide tools allowing better delineation of the pathogenesis of disease. These molecular tools for both bacteria and host should now be applied to multicenter pediatric studies that evaluate disease outcome. More recent developments indicate that a better understanding of the microbial-host interaction is critical to furthering knowledge with respect to H pylori-induced diseases. Studies are needed to evaluate either DNA-based or more traditional protein-based vaccines, to evaluate more specific antimicrobials that confer minimal resistance, and to evaluate probiotics for the management of H pylori infection. Multicenter multinational studies of H pylori infection in the pediatric population, which include specific, randomized controlled eradication trials, are essential to extend current knowledge and develop better predictors of disease outcome.

Campylobacter gastritis simulating Menetrier's disease by upper gastrointestinal radiography

Within this decade it has been determined that primary gastritis in both children and adults is frequently associated with infection of the gastric mucosa with Campylobacter pylori. It is characterized by a chronic inflammatory process in which the mucosa of the gastric antrum is typically most severely involved. Other regions of the stomach may be involved and associated peptic ulcers of the stomach and duodenal bulb are frequent. A case of C. pylori gastritis is reported in which involvement of the gastric fundus and body produced severe rugal hypertrophy that resembled Menetrier's disease.

The disease spectrum of Helicobacter pylori: the immunopathogenesis of gastroduodenal ulcer and gastric cancer

Helicobacter pylori is a gram-negative bacterium that resides under microaerobic conditions in a neutral microenvironment between the mucus and the superficial epithelium of the stomach. From this site, it stimulates cytokine production by epithelial cells that recruit and activate immune and inflammatory cells in the underlying lamina propria, causing chronic, active gastritis. Although epidemiological evidence shows that infection generally occurs in children, the inflammatory changes progress throughout life. H. pylori has also been recognized as a pathogen that causes gastroduodenal ulcers and gastric cancer. These more severe manifestations of the infection usually occur later in life and in a minority of infected subjects. To intervene and protect those who might be at greatest risk of the more severe disease outcomes, it is of great interest to determine whether bacterial, host, or environmental factors can be used to predict these events. To date, several epidemiological studies have attempted to define the factors affecting the transmission of H. pylori and the expression of gastroduodenal disease caused by this infection. Many other laboratories have focused on identifying bacterial factors that explain the variable expression of clinical disease associated with this infection. An alternative hypothesis is that microorganisms that cause lifelong infections can ill afford to express virulence factors that directly cause disease, because the risk of losing the host is too great. Rather, we propose that gastroduodenal disease associated with H. pylori infection is predominantly a result of inappropriately regulated gastric immune responses to the infection. In this model, the interactions between the immune/inflammatory response, gastric physiology, and host repair mechanisms would dictate the disease outcome in response to infection.

Is Helicobacter pylori infection in childhood a risk factor for gastric cancer?

Helicobacter pylori infection is associated with chronic gastritis and peptic ulcer disease. Furthermore, the World Health Organization has classified this organism as a carcinogen for gastric cancer. H pylori infection is mainly acquired in childhood. Children with H pylori infection are asymptomatic except for a very small number that develop peptic ulcer disease. However, if H pylori gastritis is associated with gastric cancer, do pediatricians need to screen children for this infection and treat those who are infected? In an attempt to determine the significance of the association between H pylori and gastric cancer, we have reviewed all of the English language literature on this topic. H pylori infection seems to be associated with an increased risk of developing gastric cancer. However, only a small number of infected individuals (~1%) will develop gastric cancer. Furthermore, there are potential cofactors other than H pylori that could be equally important. The effect of the eradication of H pylori alone on the development of gastric cancer is unknown. Based on our knowledge to date, we suggest that it is not indicated to treat all children with H pylori infection because of the risk of developing gastric cancer or to institute a screening and treatment program.

Histological and immunohistochemical detection of different Helicobacter species in the gastric mucosa of cats

Detailed histopathological evaluation of the gastric mucosa of Helicobacter-infected cats is complicated by the difficulty of recognizing Helicobacter organisms on hematoxylin and eosin (HE)-stained sections and the ability of multiple Helicobacter species to infect cats. In this study, the presence and localization of different species of Helicobacter in the stomachs of cats was investigated using silver staining and immunohistochemistry. Five groups containing 5 cats each were established (group 1: urease negative and Helicobacter free; groups 2, 3, 4, and 5: urease positive and infected with Helicobacter heilmannii, unclassified Helicobacter spp., Helicobacter felis, and Helicobacter pylori, respectively). Gastric samples were evaluated by HE and silver staining and by immunohistochemistry with 3 different anti-Helicobacter primary antibodies. Helicobacter were detected by Steiner stain in all infected cats at the mucosal surface, in the lumen of gastric glands, and in the cytoplasm of parietal cells. In silver-stained sections, H. pylori was easily differentiated from H. felis, H. heilmannii, and unclassified Helicobacter spp., which were larger and more tightly coiled. No organisms were seen in uninfected cats. Helicobacter antigen paralleled the distribution of organisms observed in Steiner-stained sections for 2 of the 3 primary antibodies tested. The antisera were not able to discriminate between the different Helicobacter species examined. A small amount of Helicobacter antigen was present in the lamina propria of 3 H. pylori-, 3 H. felis-, and 1 H. heilmannii-infected cat. Minimal mononuclear inflammation was present in uninfected cats and in those infected with unclassified Helicobacter spp. and H. heilmannii cats. In H. felis-infected cats, lymphoid follicular hyperplasia with mild pangastric mononuclear inflammation and eosinophilic infiltrates were present. The H. pylori-infected cats had severe lymphoid follicular hyperplasia and mild to moderate mononuclear inflammation accompanied by the presence of neutrophils and eosinophils. These findings indicate that Steiner staining and immunohistochemistry are useful for detecting Helicobacter infections, particularly when different Helicobacter species can be present. Monoclonal antibodies specific for the different Helicobacter species could be important diagnostic aids. There appear to be differences in the severity of gastritis in cats infected with different Helicobacter species.

Comparison of immunohistochemistry and silver stain for the diagnosis of pediatric Helicobacter pylori infection in urease-negative gastric biopsies

We compared immunohistochemical and silver stains of pediatric gastric biopsy sections for the identification of Helicobacter pylori infection with chronic inflammation and a negative urease screening test. Thirty-seven patients (age range 10 months to 21 years) whose gastric antral biopsies were negative for the rapid urease test (CLO(R)) but positive for lymphocytic infiltration were selected for a retrospective study. Specimens had been subjected to a rapid urease test (CLO(R)) and hematoxylin and eosin staining, and Dieterle silver staining and immunohistochemical staining specific for H. pylori were also performed. Twelve additional patients with urease-positive biopsies were used as controls. With Dieterle staining, 8/37 (22%) urease-negative biopsies contained organisms morphologically compatible with H. pylori, 21/37 (56%) contained organisms not compatible with H. pylori, and 8/37 (22%) were negative for organisms. Immunostaining confirmed 6/8 (75%) Dieterle-positive cases as being H. pylori, was negative in 2/8 (25%) Dieterle-positive cases, and was positive in 2/8 (25%) Dieterle-negative cases. Biopsies from 8/12 (67%) urease-positive specimens contained organisms seen with both Dieterle and immunohistochemical stains, and 4/12 (33%) were negative with both stains. Although both stains yielded comparable results with H. pylori-positive biopsies, Dieterle staining was potentially confusing because of nonspecific staining of other organisms. A significant proportion of (CLO(R))-negative biopsies was positive for H. pylori with special stains. We therefore recommend the use of immunohistochemical staining rather than silver staining in the evaluation of urease-negative gastric biopsies demonstrating chronic inflammation in children.

Evaluation of urinary rapid test for Helicobacter pylori in general practice

There is increasing interest in noninvasive tests for the diagnosis of Helicobacter pylori (H. pylori) infection. One such test, a urine-based rapid test kit (RAPIRUN H. pylori Antibody, Otsuka Pharmaceutical Co., Ltd.) for detection of antibody to H. pylori, has been developed and is considered ideal. In addition to its noninvasiveness and safe handling-due to use of urine as a sample-the assay procedure used for the urinary rapid test is very simple. Only 10-20 minutes are required to complete an assay, and no instruments are needed. The aim of this study was to examine the clinical usefulness of this urine-based rapid test. A total of 189 patients, including 76 patients with gastroduodenal disease, were recruited. A pair of random single-void urine and serum samples was collected from each of the 189 patients, and antibody to H. pylori in the urine and serum samples was measured using the urine-based rapid test kit and three commercially available serum-based ELISA kits. For the patients with gastroduodenal disease, invasive diagnostic methods using endoscopic biopsy specimens such as culture, histology, and rapid urease test were also performed. The sensitivity, specificity, and accuracy of the urinary rapid test were evaluated on the basis of the three serum ELISA results or the invasive diagnostic results. In addition, various urinalyses were performed, and the effects of substances existing in urine on the urinary rapid test results were examined. Of the 189 patients, the urinary rapid test was positive for 110 (58.2%), negative for 78 (41.3%), and invalid for only one patient (0.5%). Based on the three serum-based ELISA results, the sensitivity, specificity, and accuracy of the urinary rapid test were 93.7, 88.9, and 92.2%, respectively. On the basis of the biopsy-based test results, the sensitivity of the urinary rapid test was 100% and its accuracy (95.2%) was equivalent or superior to that of each serum-based ELISA. In addition, no significant differences were observed between groups positive and negative on urinary rapid testing in any urinalysis parameter examined. The novel urinary rapid test kit evaluated in this study enables simple, rapid, and accurate diagnosis of H. pylori infection, and is an ideal test method for point-of-care testing.

Antral nodularity identifies children infected with Helicobacter pylori with higher grades of gastric inflammation

BACKGROUND

The endoscopic pattern of antral nodularity is a peculiar finding in children with Helicobacter pylori infection. The aim of this study was to determine whether this finding is related to more severe gastritis.

METHODS

One hundred seventy-four consecutive children (median age 8.7 years) referred for gastroscopy were studied. Biopsy specimens from the antrum and body of the stomach were taken to assess H pylori status, gastritis score, and lymphoid follicles. Clinical diagnosis, major symptoms and endoscopic findings were recorded.

RESULTS

Eighty-four (48%) children (median age 10.5 years) had evidence of H pylori infection. The endoscopic pattern of antral nodularity was found only in children infected with H pylori (34/84, 40.5% vs. 0/90, 0%, p < 0.0001% 100% specificity, 40.5% sensitivity). Among all children infected with H pylori, the gastritis score was higher (p < 0.0001) in those with antral nodularity (n = 34) than in those without (n = 50). Completely normal gastric mucosal histology was never found in children infected with H pylori with antral nodularity. The presence and number of lymphoid follicles was strongly related to the finding of antral nodularity (p < 0.01).

CONCLUSIONS

The endoscopic pattern of antral nodularity identifies children with H pylori infection, severe gastritis, and increased lymphoid follicles.

Helicobacter pylori infection in children of Texas

BACKGROUND

Acquisition of the Helicobacter pylori infection usually occurs in childhood. The prevalence of infection differs among ethnic groups and in adults is inversely related to the socioeconomic status of the individual's family during childhood. This study investigates the seroprevalence of H. pylori infection in children of different ethnic groups in relation to socioeconomic class and investigates the prevalence of acute H. pylori infection among children who have had recent onset of abdominal pain.

METHODS

Serum samples were collected from 797 children, aged 6 months to 18 years, of various socioeconomic and ethnic backgrounds, at a large urban children's hospital. H. pylori status was determined by an anti-H. pylori immunoglobulin (Ig)G enzyme-linked immunosorbent assay (ELISA) validated for pediatric use. To determine the prevalence of acute H. pylori infection, children brought to the emergency center with abdominal symptoms without diarrhea and overt signs of acute abdomen were evaluated with both serology and the 13C-urea breath test. Acute H. pylori was defined as a positive 13C-urea breath test result and negative IgG serology for H. pylori.

RESULTS

The overall seroprevalence of H. pylori was 12.2% and increased with age (e.g., 8.3% at 6-11.9 months and 17.9% at 13 years). The prevalence was inversely related to socioeconomic status (6.6%, moderate to high vs. 15%, low socioeconomic status). The difference in seroprevalence among blacks (16.8%), Hispanics (13.3%), and whites (8.3%; P < 0.01) could be accounted for by differences in socioeconomic status. Eighteen percent of children who were evaluated at the emergency center for recent-onset abdominal pain had acute H. pylori infections.

CONCLUSIONS

Socioeconomic status, not ethnic group, is the more important risk factor for acquisition of H. pylori infection during childhood. Acute H. pylori infection was a relatively common cause of recent-onset, nonsurgical abdominal pain.

Helicobacter pylori infection in recurrent abdominal pain

BACKGROUND

Helicobacter pylori is associated with chronic gastritis and peptic ulcer in adults and in children. The purpose of the present study was to analyze the association of recurrent abdominal pain and H. pylori infection in children and to evaluate the efficacy of antimicrobial treatment in patients with evidence of infection.

METHODS

The clinical and histopathologic findings in children who underwent diagnostic upper endoscopy for recurrent abdominal pain were analyzed retrospectively. Patients with evidence of infection with H. pylori were treated with a combination of omeprazole, amoxicillin, and clarithromycin. Efficacy of treatment was assessed using the 13C-urea-breath test.

RESULTS

H. pylori was found in histopathologic sections of 29 (40%) of 73 patients undergoing diagnostic endoscopy for recurrent abdominal pain. Five children (17%) were of Swiss ethnic origin, and 24 (83%) were non-Swiss. All the infected patients had chronic gastritis and 4 (14%) had ulcerations in the duodenum. Treatment with omeprazole, amoxicillin, and clarithromycin resulted in eradication of the infection in all and in resolution of the clinical symptoms in 15 (80%) of 19 patients who had a follow-up examination.

CONCLUSIONS

The presented data suggest that gastritis induced by H. pylori may be associated with recurrent abdominal pain and that in Switzerland infections with H. pylori primarily involve persons who are non-Swiss. A combined therapy results in eradication of the bacterium and in improvement of the clinical symptoms in a significant majority of the patients.

A comprehensive review of the natural history of Helicobacter pylori infection in children

Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.

Is Helicobacter pylori a cause of infantile hypertrophic pyloric stenosis?

My hypothesis is that infantile hypertrophic pyloric stenosis (IHPS) is caused in some cases by Helicobacter pylori (HP) a bacterium commonly found in the human stomach. IHPS is an idiopathic condition of infancy. It occurs at about 5 weeks of age in 3 per 1000 newborns. Children with IHPS have structurally normal pylori at birth and do not resemble children with congenital anomalies. Some nonspecific evidence (temporal distribution, seasonality, familial clustering, leukocytic infiltrates, and increased risk with bottle feeding) are compatible with an infectious etiology. Some other epidemiologic features of IHPS, such as its strong male predominance, its racial and social class variation, and a possible drop in its incidence, are also features of HP infection. Clinical features of IHPS, such as vomiting, hematemesis, and esophagitis, are also consistent with HP. Finally, children with IHPS appear to be more likely to develop chronic conditions, such as peptic ulcers, now known to be caused by HP.

New immunoassay in stool provides an accurate noninvasive diagnostic method for Helicobacter pylori screening in children

OBJECTIVE

The noninvasive (13)C-urea breath test (UBT) is a reliable diagnostic method for detection of Helicobacter pylori infection in children, and it avoids invasive gastrointestinal endoscopy. In this study, we compared a noninvasive, newly developed fecal H pylori antigen test with the UBT.

METHODOLOGY

One hundred sixty-two children (76 girls and 86 boys) were tested for H pylori infection using the UBT and a new antigen test in stool samples. The H pylori stool test is based on a sandwich enzyme immunoassay with antigen detection.

RESULTS

Twenty-four of the children (14.8%) with dyspepsia tested positive for H pylori according to the breath test results. In 22 of the 24 patients, H pylori antigen could be detected in the stool (sensitivity: 91.6%). Of 138 patients with negative UBT results, 136 were H pylori-negative in the stool test (specificity: 98.6%).

CONCLUSIONS

The new, noninvasive, low-cost H pylori antigen test in stool can replace the UBT for detection of H pylori infection in children with comparable reliability and accuracy.

Alterations in exon 4 of the p53 gene in gastric carcinoma

BACKGROUND & AIMS

Our long-term goal was to evaluate the role of p53 in the prognosis of gastric cancer. We previously showed a discrepancy between p53 expression and the presence of mutations when only exons 5-9 were examined. We then evaluated exon 4.

METHODS

DNA was sequenced from 217 gastric cancers to detect exon 4 alterations. Codon 72 was examined by restriction enzyme digestion.

RESULTS

Mutations were present in 3.2% of tumors. In addition, 2 polymorphic sites were found at codons 36 and 72. Polymorphisms at codon 36 were only found in 2 patients. In contrast, the codon 72 polymorphism was very frequent. The genotype frequency was arg/arg (54%), arg/pro (33%), and pro/pro (14%). The genotype of the polymorphic site varied with race (P = 0.001): 64% of whites had the arg/arg genotype, compared with 24% of blacks. The difference in genotype by site, sex, or histological tumor type was not statistically significant (P = 0.067).

CONCLUSIONS

There are several exon 4 alterations in gastric cancers. These include the rare mutations and the very rare codon 36 polymorphism. The most common change is the codon 72 polymorphism, the genotype of which differs significantly with race. The more common arg/arg genotype in whites may explain why whites are more prone to develop cardiac cancer, whereas the more common proline allele in blacks may explain why they are more prone to develop antral cancers. Further studies are required to determine whether the codon 72 polymorphism affects patient predisposition to gastric cancer.

Is gastric nodularity a sign for gastric inflammation associated with Helicobacter pylori infection in children?

The aim of this study was to investigate the accuracy of using gastric nodularity (GN) as a marker for gastric inflammation associated with Helicobacter pylori infection in children. A retrospective analysis of 395 upper endoscopies done in children between 1990-1996 was performed. Demographics, clinical symptoms, endoscopic features, rapid urease test (RUT), and histological results were collected from each report. GN was found in 13 (3.5%) children. GN showed a significant correlation with age but not with gender. Multiple regression analysis showed a significant correlation between GN and gastritis with RUT but not with other histological determinants alone (gastritis, RUT, or H. pylori organisms). Nevertheless, GN had a poor accuracy rate to determine H. pylori-associated gastritis (sensitivity, 61%; positive predictive value, 12%). GN is a poor predictor for gastric inflammation associated with H. pylori infection in children. During endoscopy, gastric biopsies should always be obtained in children to establish the presence of mucosal inflammation.

Expression and activation of NF-kappa B in the antrum of the human stomach

Both in vitro studies and experiments in mice suggest a key role for transcription factor NF-kappa B as a mediator of mucosal inflammation. Experiments in vitro show that NF-kappa B activation may be a critical event in the production of proinflammatory molecules in Helicobacter pylori-associated gastritis. This study examines the expression and activity of NF-kappa B in situ in antral biopsies of 69 consecutive patients with immunohistochemical techniques. In the uninflamed stomach, NF-kappa B was highly expressed and active in a subset of epithelial cells, which were identified as predominantly G cells. In accordance with this activity, G cells were shown to express high levels of the NF-kappa B target cytokine TNF-alpha, a well-documented stimulator of gastrin production. In patients with H. pylori-associated gastritis, NF-kappa B activity was markedly enhanced. Activation occurred preferentially in the epithelial cells. The number of cells showing activated NF-kappa B correlated with the activity of gastritis, a measure of neutrophil influx, whereas no correlation was found with the chronicity of inflammation, a measure of the presence of mononuclear inflammatory cells. This correlation is direct evidence of the importance of NF-kappa B-dependent signal transduction for neutrophil influx in H. pylori-associated gastritis.

A prospective trial of lansoprazole triple therapy for pediatric Helicobacter pylori infection

BACKGROUND

Triple therapy with a proton-pump inhibitor and two antibiotics is widely used in the treatment of Helicobacter pylori infection in adults. Experience with such therapy in the pediatric population is limited. This was a prospective, nonrandomized, open-label trial to evaluate safety and efficacy of a combination of lansoprazole, clarithromycin, and amoxicillin in symptomatic children with H. pylori infection.

METHODS

Children with H. pylori gastritis diagnosed by endoscopy performed for persistent nausea, vomiting, recurrent abdominal pain, and diarrhea with consistent histology were treated with the regimen of 0.45 mg/kg per day lansoprazole divided into two doses (maximum dose, 15 mg twice daily), amoxicillin 40 mg/kg per day in two doses (maximum dose, 1.0 g twice daily), and 250 mg clarithromycin twice daily (<10 years old) or 500 mg twice daily (>10 years old) for 2 weeks. Pre- and posttreatment endoscopic biopsy specimens were graded for the severity of gastritis and H. pylori density by a blinded pathologist. A questionnaire for assessing the severity of symptoms at the time of initial and second endoscopy were completed by patient and/or parent.

RESULTS

Thirty-two children (age range, 1-25 years; mean age, 11 years; 19 females, 13 males) were treated with this regimen during an 18-month period. H. pylori organisms with varying grades of gastritis were present in tissue specimens of all patients. Only 28 children had follow-up endoscopy, which showed eradication of H. pylori in 15 (54%) children. Histologic symptoms of gastritis improved after therapy in the whole group. Overall, symptoms of vomiting, abdominal pain, diarrhea, anorexia, and halitosis significantly improved (P < 0.05). Minor adverse effects of therapy occurred in 25% of patients.

CONCLUSIONS

Symptoms, histologic, and endoscopic findings improved after triple therapy in children with H. pylori gastritis; however, eradication of bacteria was achieved in only 56% of children.

Low rates of Helicobacter pylori reinfection in children

BACKGROUND & AIMS

Reinfection after treatment for Helicobacter pylori is uncommon in adults. It is more likely to occur in children because they acquire primary infection. The aim of this study was to determine whether children are likely to become reinfected with H. pylori and if there are any risk factors for reinfection.

METHODS

A prospective study of children who had documented evidence of successful treatment for H. pylori infection was performed. Sixty children were eligible for inclusion; results for 52 are presented. Children, parents, and siblings underwent [(13)C]urea breath tests. Details of family size and socioeconomic status were documented. Cox logistic regression analysis was used to determine the risk factors for reinfection.

RESULTS

The duration of follow-up was 103.8 patient-years (mean +/- SD, 24 +/-14.0 months). Forty-six (88.5%) of the index children remained clear of infection, and 6 (11.5%) children were reinfected. The mean age of those who became reinfected was 5.8 +/- 5.6 years compared with 12.3 +/- 3.0 years for those who remained clear of infection (P = 0.00001). Only 2 of 46 (4.3%) children older than 5 years of age were reinfected, although 80.8% had 1 infected parent and 65% of siblings were infected. Reinfection rate was 2.0% per person per year in children older than 5 years. Living with infected parents and siblings and low socioeconomic status were not risk factors for reinfection. In logistic regression analysis, age was the only risk factor for reinfection.

CONCLUSIONS

Reinfection with H. pylori occurs rarely in children older than 5 years of age regardless of socioeconomic group or number of infected family members. These findings also indicate that it is not necessary to treat all family members to achieve long-term eradication of H. pylori.

Changes in seroepidemiological pattern of Helicobacter pylori and hepatitis A virus over the last 20 years in Japan

OBJECTIVE

The age groups most susceptible to infection and the mode of transmission of Helicobacter pylori (H. pylori) are not yet clear. To contribute to a better understanding of this disease, this study was undertaken to evaluate changes in the seroepidemiological pattern of H. pylori in a group of Japanese people over the last 20 yr sampled in 1974, 1984, and 1994 in comparison with that of the hepatitis A virus (HAV), which was used as a marker of the fecal-oral route of transmission.

METHODS

A total of 1015 serum samples were obtained from the National Institute of Infectious Diseases in Tokyo. All of these samples were from healthy persons aged 0-89 yr (442 male and 573 female; median age 35.6 yr), living in seven prefectures in the central part of Japan in 1974, 1984, and 1994. All serum samples were assayed for H. pylori IgG by means of enzyme-linked immunosorbent assay (ELISA). Further, anti-HAV antibodies were assayed by blocking ELISA in the same samples. We investigated the prevalence of H. pylori and HAV for all ages, and the positive rate of H. pylori for infants and children separately.

RESULTS

The overall prevalence of H. pylori antibodies was 72.7% (CI 95%, 68.0-77.3) in 1974, 54.6% (CI 95%, 49.1-60.0) in 1984 and 39.3% (CI 95%, 34.1-44.4) in 1994. That of HAV was 57.7% (CI 95%, 52.5-62.8) in 1974, 41.7% (CI 95%, 36.3-47.0) in 1984, and 23.4% (CI 95%, 18.9-27.8) in 1994. The prevalence of both H. pylori and HAV was found to increase with age, whereas there have been clear cohort shifts in the seroepidemiological patterns of both infections over the last 20 yr in Japan. This study shows that there is a slight similarity in the concordance of positive and negative populations between H. pylori and HAV. However, it was very difficult to determine the concordance between H. pylori and HAV infection in this study.

CONCLUSIONS

Our data strongly suggest that the highest infection rates for both H. pylori and HAV occur among infants and children in Japan. This study provides evidence that H. pylori and HAV may share a common mode of transmission but that changes in environmental conditions make this very difficult if not impossible to prove with seroepidemiological data.

Peptic ulcer disease in childhood in Zaria, Nigeria

Over a 10-year period in a busy paediatric surgical unit, six children were operated upon for peptic ulcer disease, four of whom presented with complications (pyloric stenosis, two; perforation, one; bleeding, one). Truncal vagotomy with a drainage procedure was the operation of choice in five of the children in whom there were no complications. One child suspected of having Zollinger-Ellison syndrome had recurrence of symptoms. Symptoms of peptic ulcer disease in children are non-specific, and in our environment such symptoms are frequently considered to be due to parasitic infestation. Barium meal is not very sensitive in diagnosis in children, and the relative lack of availability of endoscopic services limits pre-operative diagnosis. It is suggested that peptic ulcer disease be considered in children who have persistent or recurrent abdominal pain of obscure aetiology.

Helicobacter pylori and nonulcer dyspepsia in childhood: clinical pattern, diagnostic techniques, and bacterial strains

BACKGROUND

This is a report of the results of a multicenter study performed in children with dyspepsia from five pediatric centers in Puglia, a region in southern Italy. In the study, clinical features of Helicobacter pylori infection, the reliability of diagnostic techniques, and the involvement of bacterial strains were examined.

METHODS

Fifty-three outpatients with dyspepsia enrolled in our study and compiled a diary recording clinical symptoms in patients before they underwent the following diagnostic techniques: endoscopy, biopsy for histologic analysis, rapid urease test, 13C urea breath test, serology specific for immunoglobulin (Ig)G and anti-CagA and VacA.

RESULTS

H. pylori showed a prevalence of 30.2% (n = 16). Histologic positivity was seen in all patients at the antral level (H. pylori-associated chronic gastritis). In the gastric body, bacterial chronic active gastritis was present only in six patients (H. pylori-associated chronic pangastritis). Clinical evaluation showed a significant difference in favor of subjects positive for H. pylori only for epigastric burning and/or pain (p < 0.001). The comparison of results of diagnostic tests, using histology as the gold standard, showed sensitivity and specificity of more than 93% for 13C urea breath test and more than 85% for rapid urease test and serology. Anti-CagA antibodies were found in 64.3% and anti-VacA antibodies in 42.8% of H. pylori-positive patients.

CONCLUSIONS

H. pylori prevalence in children with dyspepsia from the geographic area studied is comparable with that found in other developed countries. Approximately 50% of the studied patients were infected by cytotoxic strains. The urea breath test was the most reliable noninvasive diagnostic tool and is suitable for routine use, although endoscopy with histologic assessment remains the definitive investigation and is particularly important in patients with positive serology for CagA and VacA. Finally, the frequency of aggressive strains in our region seems to affect the clinical pattern; this emphasizes the importance of definitive diagnosis in children and offers a new role for serology.

The prevalence of antibody to CagA in children is not a marker for specific disease

BACKGROUND

In adults, a high prevalence of antibody to the cytotoxin-associated antigen (CagA) of Helicobacter pylori has been linked to the development of more serious gastroduodenal disease. Few investigators have examined this association in children. The purpose of this study was to investigate the seroprevalence of antibody to the CagA antigen as well as other specific H. pylori antigens in children.

METHODS

By use of an immunoblot analysis kit, the immune response to specific H. pylori antigens in serum collected from 21 H. pylori-positive symptomatic Australian children, 5 with peptic ulcer disease and 16 with nonulcer dyspepsia, and 33 H. pylori-positive asymptomatic Chinese children. Sera from 20 H. pylori-negative symptomatic Australian children were used as control subjects.

RESULTS

Antibody responses to the 26.5-kDa, 30-kDa, and 116-kDa (CagA) antigens were found to be the most prevalent, with 81.5%, 79.6%, and 76% of children, respectively, mounting a response. In contrast, antibody responses to the 19.5-kDa, 35-kDa, 45-kDa, 60-kDa, 89 kDa (VacA), and 180-kDa antigens occurred in 55.5%, 24%, 16.7%, 63%, 37%, and 7.4% of children, respectively. A higher prevalence of antibody response to CagA was found in the symptomatic Australian children with peptic ulcer disease (100%) compared with prevalence in those with nonulcer dyspepsia (56.3%), but the difference did not reach statistical significance. No significant difference was found between the prevalence of antibody to CagA in the Australian peptic ulcer disease group (100%) and that in the asymptomatic Chinese children (81.8%).

CONCLUSION

These results suggest that in children CagA is not a marker of specific disease development.

Peptic ulcer disease and exposure to domestic pets

OBJECTIVES

This study assessed whether an association exists between household pets and peptic ulcer disease.

METHODS

Canadian adults (n = 15,779) were asked about cats or dogs in their household and about history of peptic ulcer disease. Logistic regression was used to assess the association between pet ownership and a history of peptic ulcer disease, after adjustment for sociodemographic differences.

RESULTS

No relationship was observed between report of household pets and a history of peptic ulcer disease (adjusted odds ratio = 1.14, 95% confidence interval = 0.95, 1.36).

CONCLUSIONS

In a large sample of Canadian adults, no association was observed between pet ownership and a history of peptic ulcer disease.

Effect of Helicobacter pylori eradication on the natural history of duodenal ulcer disease

BACKGROUND

Duodenal ulcer disease is strongly associated with Helicobacter pylori infection of the gastric mucosa. Eradication of H pylori from the gastric mucosa in adults is associated with long term healing of ulcers.

AIMS

To follow a cohort of children with duodenal ulcer disease for a minimum of two years after the eradication of H pylori.

PATIENTS AND METHODS

Over a three year period, all children diagnosed with duodenal ulcer disease had their symptoms documented and their H pylori status evaluated. The histories of these children were carefully screened to determine previous symptoms and to document previous treatment regimens.

RESULTS

Sixteen children were diagnosed with ulcers and 15 were available for treatment and long term follow up. The median age at which symptoms first occurred was 10.5 years (range, 6-14) and the median duration of symptoms was 24 months (range, 2-60). Ten of the children had been treated with H2 receptor antagonists for a median of 3.5 months (range, 1-60). Duodenal ulcers healed in all children after eradication of H pylori and all children have remained asymptomatic for a median of 37 months (range, 26-62). No child has required subsequent admission to hospital.

CONCLUSION

Eradication of H pylori is very effective in the long term healing of duodenal ulcer disease. H pylori eradication should be the standard treatment for all infected children who present with duodenal ulcer disease.

Dyspepsia in infants and children

Pathological processes and diseases of the upper gastrointestinal tract have become increasingly recognized over recent years as childhood entities responsible for a variety of upper gastrointestinal symptoms previously labelled as functional or non-organic. The term 'dyspepsia' is an adult one whose definition requires clarification before use in the paediatric context, but it encompasses age-dependent symptoms such as feed-associated irritability in the infant, peri-umbilical pain in the younger child, and heart-burn, nausea, and indigestion in the older child as in adults. The possible organic conditions giving rise to such symptoms are multiple and multiorgan and include: gastro-oesophageal reflux; peptic ulcer disease; upper gastrointestinal Crohn's disease; antroduodenal motility disorders; pancreatitis; cholecystitis; cholelithiasis; biliary dyskinesia; and abdominal migraine. However, Munchausen syndrome by proxy must not be forgotten. Non-ulcer dyspepsia, it is now clear, has a basis in altered gastroduodenal motility and may be amenable to propulsion agents. In many individuals the dyspeptic symptoms of recurrent abdominal pain may be altered by psychotherapeutic intervention. Indeed there remains a proportion of children who undoubtedly have a behavioural or psychological base to their complaint. Nevertheless, with the recent increase in diagnostic yield from improved technical investigative aids available to paediatrics in the last 5-10 years, it is clear that the responsibility of the paediatrician to the child to find a cause of their symptoms is paramount. The variety of presenting features, possible causes of these symptoms, and appropriate investigation and treatment will be discussed, and management algorithms based on published literature and personal practice will be offered.

Antimicrobial therapies for Helicobacter pylori infection in gnotobiotic piglets

Gnotobiotic piglets infected with Helicobacter pylori were treated with various antimicrobials as monotherapy and dual therapy, and the results were compared to those for piglets treated with a triple-therapy regimen (bismuth subsalicyclate at 5.7 mg/kg of body weight, metronidazole at 4.4 mg/kg, and amoxicillin at 6.8 mg/kg four times a day [QID]). Clearance of infection was assessed after 7 days of treatment, and eradication was assessed following 7 days of treatment and a 14-day posttreatment observation interval. Monotherapy with amoxicillin, clarithromycin, and ciprofloxacin cleared and eradicated the organism from porcine stomachs; monotherapy with metronidazole cleared the infection and eradicated it from some piglets. Metronidazole-resistant microbes were recovered from treated piglets which cleared but did not eradicate the infection. Monotherapy with bismuth subsalicylate, erythromycin, nitrofurantoin, and tetracycline in the dosage range of 5.0 to 7.1 mg/kg QID was less than 100% effective in clearance and eradication, in that these drugs cleared and/or eradicated the infection from some of the piglets but did not eradicate the infection from all of the piglets. Monotherapy with an H-2 receptor antagonist (ranitidine) or a proton pump inhibitor (omeprazole) was ineffective at either clearance or eradication. In vivo dose titrations with several effective monotherapies were performed to determine the lowest effective in vivo dose of drug. In piglets, eradication was associated with a statistically significant decline in serum H. pylori-specific immunoglobulin M (IgM) antibodies; the titers of both IgA and IgG also declined, but the values were not statistically significant. For many antimicrobials, piglets are more sensitive indicators of clearance and eradication than humans. These data establish the H. pylori-infected gnotobiotic piglet as a useful model for the identification of novel antimicrobials for the treatment of this disease and for drug assessment during preclinical evaluations.

One-week triple therapy with omeprazole, clarithromycin, and nitroimidazole for Helicobacter pylori infection in children and adolescents

BACKGROUND

Resolution of Helicobacter pylori infection is important in the management of peptic ulcer disease and reduces peptic ulcer recurrence in both adults and children. Various anti-H pylori treatment regimens have been proposed, reflecting the incomplete clinical success of each. A combination of omeprazole, clarithromycin, and tinidazole, given for 1 week, has been shown to be highly tolerable and effective, achieving a success rate of >90% in the adult population.

OBJECTIVE

The aim of this study was to evaluate this short-term regimen in pediatric and adolescent populations.

METHODS

The study group consisted of 35 children referred for evaluation of dyspeptic symptoms. They all underwent upper gastrointestinal endoscopy, in which H pylori infection was confirmed by rapid urease test and/or histologic staining. They were given omeprazole (20 mg twice daily), clarithromycin (250 mg twice daily), and tinidazole or metronidazole (500 mg twice daily) for 1 week. The patients were divided into two groups: those who received the first course of anti-H pylori therapy during this study (group 1) and those who had previously received standard metronidazole and bismuth combination therapies that failed to eradicate H pylori (group 2). Therapeutic efficacy was assessed by a 13C-urea breath test performed 4 weeks after completion of treatment. Results. The 35 study patients had a mean age of 15.9 years (range, 10 to 19) and included 19 males and 16 females, of whom 22 were born in Israel and 13 were immigrants from the former USSR. There were 27 patients (77. 1%) in group 1 and 8 patients (22.9%) in group 2. Endoscopic findings were nodular gastritis (14), gastritis (11), gastric ulcer (1), duodenal ulcer (5), and duodenitis (4). H pylori resolution was significantly higher in group 1 patients (24/27, 88.9%) than in group 2 patients (1/8, 12.5%). There was no difference between patients with nodular gastritis and those with nonnodular gastritis, and between Israeli-born patients and patients born in the former USSR. Compliance in both groups was equally good, and no major side effects were recorded.

CONCLUSIONS

One-week omeprazole/clarithromycin/tinidazole triple therapy is highly tolerable and effective for treating H pylori in the pediatric age group, but previous treatment failure diminishes the likelihood of success with this regimen.

Carbon 13-labeled urea breath test for the diagnosis of Helicobacter pylori infection in children

Helicobacter pylori infection is mainly acquired in childhood, and studies on the epidemiology of this infection depend on the availability of a noninvasive diagnostic test for use in children. The aim of this study was to determine whether the carbon 13-labeled urea breath test (UBT) can be used in children by evaluating: (1) its sensitivity and specificity compared with either culture or both rapid urease test and histologic examination, (2) whether a test meal or a prolonged fast is required, (3) the usefulness after treatment for H. pylori. Eighty-eight children (mean age, 10.6 +/- 4.19 years) who were undergoing upper endoscopy were studied while fasting, not fasting, and after treatment. Children were given 50 mg of 13C-urea if they weighed less than 50 kg or 75 mg of 13C-urea if they weighed more than 50 kg with 50 mg of a glucose polymer solution in 7.5 ml of water. Breath samples were collected at baseline and at 15, 30, 45, and 60 minutes. In 63 fasting children the UBT was 100% sensitive and 97.6% specific at 30 minutes with a cutoff value of 3.5 delta 13CO2 per mil. Nonfasting tests in 23 children, performed between 1 and 2 hours after their usual meal, were 100% sensitive and 91.6% specific. In 13 children fed directly before the UBT, the sensitivity of the test was reduced to 50%. Thirty minutes was the optimal sampling time. There was a significant decrease in specificity when samples were obtained at 15 minutes, possibly caused by the interference of oral urease-producing organisms. The test was 100% sensitive and specific in 20 children after treatment for H. pylori infection. The UBT is a highly sensitive and specific test for the diagnosis of H. pylori infection in children. Neither a prolonged fast nor a test meal is required.

Seroprevalence of Helicobacter pylori in German infants and children

BACKGROUND

The purpose of the study was to evaluate the serological prevalence of Helicobacter pylori (H. pylori) infection during infancy and childhood in Germany.

PATIENTS AND METHODS

We quantified specific IgG antibody titers against H. pylori by enzyme-linked immunosorbent assay (ELISA) technique (BIO-RAD G.A.P. IgG-test) from healthy children under 18 years (n = 216) admitted to hospital for minor surgical procedures. All patients were age 0-18 years and lived in the southern part of Germany (Bavaria and Baden-Wuerttemberg). For each age group, 12 different sera were obtained and were determined in duplicate. We analyzed the 216 sera within 6 age groups of equal size. Mean titers > 19 U/ml were considered positive for H. pylori infection.

RESULTS

None of the sera of 48 children less than 4 years old were positive for anti-H. pylori specific IgG antibodies. Titers above 19 U/ml were found in 8.3% (3/36 sera each, CI 95% 1-21.7%) in the children age three to five and nine to 11 years. Six- to eight-year-old children showed a 19.4% seroprevalence (7/36 sera, CI 95% 8.2-48%) and children 12-14 years old showed a seropositivity of 16.7% (6/36 sera, CI 95% 6.6-46.1%). In contrast, 47.2% (17/36 sera, CI 26.5-70.3%) of the adolescents older than 14 years had positive H. pylori antibody titers (p < .01, compared to the age-group 12-14 years). The test for linear trend (seropositivity and age) was significant with p < .001. The overall incidence increase with age in prevalence of H. pylori infection was found to be 0.9% per year within this population.

CONCLUSIONS

In contrast to published data from other European and non-European countries, we could not detect H. pylori infection in German infants less than four years old by measurement of IgG antibodies. In the older subjects, seropositivity increased significantly and linearly with age.

Normal gastric histology in Helicobacter pylori-infected children

BACKGROUND

In adults, Helicobacter pylori infection is always associated with gastritis or ulcer. However, very active gastritis and ulcers are rarely seen in children. The aim of the present work was to study the relationships between H. pylori and gastric mucosa in children.

METHODS

Eighty infected children and adolescents including 48 (60%) neurologically impaired institutionalized patients, aged 2 months-22 years (mean 11.7 +/- 5.2 years) were studied retrospectively. All the patients underwent gastroscopy, and three antral and two fundic biopsy specimens were taken for histology and bacteriology.

RESULTS

A normal gastric mucosa was found in 22 of 80 patients (27.5%), whereas the others had gastritis (n = 58, 72.5%). There were no statistical differences between patients with normal histology and those presenting with gastritis for age, sex, ethnic background, symptoms, and the degree of bacterial colonization. The macroscopic aspect of gastritis was less frequently found in children with a normal histology compared with those with histological gastritis (p < 0.001).

CONCLUSIONS

These data show that H. pylori infection can be associated with a normal gastric histology in children.

Seroprevalence and epidemiology of Helicobacter pylori infection in patients with cirrhosis

BACKGROUND

Helicobacter pylori infection is the major pathogenic factor for peptic ulcer disease. Its epidemiology is not fully known; few data are available in patients with chronic liver disease.

AIMS

To investigate the seroprevalence and factors associated with Helicobacter pylori infection in a series of liver cirrhosis patients.

METHODS

Two hundred and twenty consecutive patients were prospectively included in a study aimed to evaluate the effect of dietary intervention on cirrhosis complications and survival. At inclusion, an epidemiological and clinical questionnaire was completed. Sera were obtained and stored at -70 degrees C until analyzed. They were tested for Helicobacter pylori antibodies using a commercial ELISA kit.

RESULTS

Eleven out of 220 patients had borderline anti-Helicobacter pylori IgG titers. Of the remaining 209 patients, 105 (50.2%) showed positive titers of Helicobacter pylori IgG. Univariate analysis showed that Helicobacter pylori infection was more frequent in older patients, those born outside Catalonia, and in patients with a low educational level. Past ethanol consumption and current smoking correlated negatively with Helicobacter pylori infection. Multivariate analysis selected age (OR 3.1. 95% CI 1.46-6.45), educational level (OR 2.2. 95% CI 1.18-4.2) and alcohol consumption (OR 0.7. 95% CI 0.45-0.99) as the variables independently related to Helicobacter pylori infection.

CONCLUSIONS

Helicobacter pylori infection in cirrhosis has the same epidemiological pattern as in the general population. Suggestions that the etiology or the severity of the liver disease could be related to Helicobacter pylori infection were not confirmed by our study.

Helicobacter pylori acquisition in infancy after decline of maternal passive immunity

We evaluated the natural history of Helicobacter pylori infection and the host immune response in 80 infants, and determined seroprevalence of H. pylori infection in their Taiwanese mothers. Decline in passively transferred maternal anti-H. pylori IgG antibodies and subsequent H. pylori infection was assessed in infants over 14 mo. A sensitive and specific, 96-well microtiter ELISA for the detection of H. pylori IgG antibodies was used to evaluate maternal serum (single specimen) and their infants (birth, 1, 2, 3, 6, 12, and 14 mo). Sera were also evaluated by ELISA for the presence of anti-H. pylori IgM antibodies in the infants. Maternal H. pylori IgG seroprevalence was 62.5% [50/80; 95% confidence intervals (CI), 51-73%]. All infants born to the 50 seropositive mothers passively acquired maternal H. pylori IgG. Transplacentally transferred maternal anti-H. pylori IgG lasted until about the 3rd mo of life, and disappeared in nearly all the infants by 6 mo of age. Seven and one-half percent of infants (6/80; 95% CI, 3-16%) acquired H. pylori infection; two were born to H. pylori-negative mothers. Among the six IgG seropositive infants, an IgM response specific for H. pylori antigens was detected and appeared to precede the rise in IgG in five. We conclude that maternal passive transfer of IgG antibodies occurs in the infant and disappears by 6 mo of age. H. pylori infection is acquired in infancy in this population; IgM antibodies against H. pylori are detectable, seem short-lived, and appear to precede IgG antibody development.

Helicobacter pylori duodenal colonization in children

To investigate the prevalence and the significance of Helicobacter pylori duodenal colonization, endoscopic duodenal biopsies were performed in 168 children with chronic abdominal pain, gastroesophageal reflux, gastrointestinal bleeding, and malabsorption syndrome. Helicobacter pylori infection was detected in 68 children (40.4%): in 31 of them H. pylori was present in the gastric antrum, and in 37 in the duodenum also. Duodenitis was observed in 25 children with duodenal H. pylori; gastric metaplasia in 3. Scanning electron microscopy revealed the presence of the micro-organism in 3/13 cases; the bacteria were located in the intercellular spaces and alterations of the epithelial surface were found. In conclusion, H. pylori gastritis in children is often associated with duodenal colonization which can cause duodenitis, and also without gastric metaplasia, which indicates a possible role of the micro-organism in the pathogenesis of the lesions.

One week treatment for Helicobacter pylori infection

Helicobacter pylori is associated with primary antral gastritis, duodenal ulceration, and gastric cancer. Current regimens for treating infection in children using bismuth and antibiotics for two to six weeks are cumbersome. The aim of this study was to evaluate a one week course of treatment. All children undergoing endoscopy were assessed for the presence of H pylori by culture, histology, rapid urease test, and 13C urea breath test. Infected children received a one week course of colloidal bismuth subcitrate 480 mg/1.73 m2/day (maximum 120 mg four times a day), combined with metronidazole 20 mg/kg/day (maximum 200 mg three times a day), and clarithromycin 15 mg/kg/day (maximum 250 mg twice a day). To optimise compliance, drugs were dispensed in a 'Redidose' box containing a compartment for each day, and subcompartments marked 'breakfast', 'lunch', 'dinner', and 'bedtime'. Compliance and side effects were assessed immediately after treatment. A urea breath test was performed at least one month after treatment. Twenty two children infected with H pylori were entered into the study; 20 of these took all doses; two children suffered significant side effects (diarrhoea and vomiting). H pylori was eradicated in 21 of the 22 children (95.45%; 95% confidence interval 77% to 100%). This study shows that H pylori infection in children can be cleared by a one week course of treatment.

Cell envelope characteristics of Helicobacter pylori: their role in adherence to mucosal surfaces and virulence

Helicobacter pylori colonises the gastric mucosa of humans and causes both antral gastritis and duodenal ulcer disease. Exactly how H. pylori causes disease is not known but several pathogenic determinants have been proposed for the organism. These include adhesins, cytotoxins and a range of different enzymes including urease, catalase and superoxide dismutase. Surface molecules of H. pylori such as flagella, lipopolysaccharide, the urease enzyme and outer membrane proteins are putative adhesin molecules. While phosphatidylethanolamine and the Lewis(b) blood group antigen have been proposed as receptor molecules for the organism the exact mechanism by which H. pylori adheres to the gastric mucosa has still to be identified. Characterisation of the adhesins of H. pylori could lead to the development of adhesin analogues for use in the inhibition of colonisation and improved therapy for ulcer disease. In vivo studies with isogenic mutants which are incapable of adhering to the gastric mucosa would greatly clarify the significance of adherence. Such mutants could possibly be useful as a vaccine against infection with wild-type organisms.