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

Gastric cancer in children and adolescents in Japan

BACKGROUND

Very limited data are available on childhood gastric cancer. Using a retrospective survey and literature review, we assessed the clinical features of gastric cancer in children and adolescents.

METHODS

We collected information on childhood gastric cancer from pediatricians of 518 hospitals that issue the title of "certified board pediatrician" approved by Japan Pediatric Society, using a questionnaire on background, diagnosis year, onset symptoms, tumor location, histology, nodular gastritis, Helicobacter pylori testing, treatment, and prognosis. Studies were collected using PubMed and the NPO Japan Medical Abstracts Society database. Data for childhood gastric cancer were abstracted from the Japanese Vital Statistics database.

RESULTS

Of the 518 hospitals, 349 returned the questionnaire, which identified four patients. Literature review identified 77 cases of gastric cancer, and we analyzed data for 80 children <16 years old. Most patients were >10 years old, and there were no sex differences. Onset symptoms ranged from abdominal pain to non-localized. Sixteen of 44 children had a family history of cancer; 10 had a family history of gastric cancer. Histologically, approximately 80% had undifferentiated-type carcinoma. Prognosis was extremely poor, and two of three tested children were positive for H. pylori infection. Childhood gastric cancer death has been declining.

CONCLUSIONS

Childhood gastric cancer is rare in Japan, and information on H. pylori in childhood gastric cancer patients is limited. Declining childhood gastric cancer rates may reflect the decreasing prevalence of infection but further study is necessary to clarify the relationship between H. pylori and gastric cancer.

Effect on Helicobacter pylori eradication therapy against gastric cancer in Japan

BACKGROUND

In Japan, there have been approximately 50 000 deaths from gastric cancer annually for over 40 years with little variation. It has been reported that most gastric cancers in Japan are caused by Helicobacter pylori infection. H. pylori eradication therapy was approved for patients with chronic gastritis by the Japanese national health insurance scheme in February 2013 for patients with an endoscopic diagnosis of chronic gastritis is positive for H. pylori. We examined the effect on gastric cancer death rate 4 years after expansion of health insurance coverage.

AIM

We conducted an epidemiological study and analyzed trends in prescription for H. pylori eradication therapy. We used the electronic medical claims database from Hokkaido, Japan to evaluate the impact of expansion of national health insurance coverage for H. pylori eradication therapy on deaths from gastric cancer.

METHODS

Data on deaths from gastric cancer were obtained from the Japanese Ministry of Health, Labour and Welfare and the Cancer Statistics in Japan (2015). Analysis of electronic claims records was performed using the National Database, mainly focusing on Hokkaido. Prescriptions for H. pylori eradication therapy and the number of patients treated for gastric cancer were also extracted from the Hokkaido database.

RESULTS

Approximately 1.5 million prescriptions for H. pylori eradication therapy were written annually. Gastric cancer deaths fell each year: 48 427 in 2013, 47 903 in 2014, 46 659 in 2015, and 45 509 in 2016, showing a significant decrease after expansion of insurance coverage for H. pylori eradication therapy (P<.0001).

CONCLUSIONS

Prescriptions for H. pylori eradication therapy increased markedly after approval of the gastritis indication by the national health insurance scheme and was associated with a significant decrease in gastric cancer deaths.

RESOLUTION OF TREATMENT-RESISTANT SUBRETINAL FLUID IN A PATIENT WITH EXUDATIVE AGE-RELATED MACULAR DEGENERATION FOLLOWING ENDOPHTHALMITIS

PURPOSE

This is the first report to the best of the authors' knowledge to show resolution of subretinal fluid and treatment requirement in a case of exudative age-related macular degeneration (eAMD) with persistent fluid despite treatment that resolved following an episode of culture-positive bacterial endophthalmitis.

METHODS

A 73-year-old man with history of eAMD of the right eye presented with acute postinjection bacterial endophthalmitis 3 days after injection. He had a history of only partially treatment-responsive eAMD that had been treated over a period of 8 years.

RESULTS

After tap-and-inject treatment of endophthalmitis with ceftazidime, vancomycin, and dexamethasone, the patient returned for follow-up with visual improvement and resolution of the subretinal fluid. The previously treatment-resistant eAMD remains quiescent without further treatment after 10 months of follow-up.

CONCLUSION

It is possible that some aspect of the infection, inflammation, or treatment of endophthalmitis had a disease-modifying impact on the eAMD. Further research into the components of endophthalmitis and its treatment may result in the discovery of new treatment approaches or treatment targets.

Diagnostic accuracy of urine Helicobacter pylori antibody test in junior and senior high school students in Japan

BACKGROUND

To prevent gastric cancer, a Helicobacter pylori test-and-treat strategy has been proposed. In Japan, routine urine examinations are performed to screen for kidney diseases; it is therefore convenient to screen for H. pylori infection via urine antibody (u-Ab) testing.

AIM

To evaluate the diagnostic accuracy of u-Ab testing in students using ¹³ C-urea breath testing (UBT) as a standard.

METHODS

The study population included 806 junior or senior high school students in Japan who provided urine samples and/or underwent UBT. Students with a positive u-Ab test or discrepant results between the u-Ab test and UBT were asked to provide additional stool and/or blood samples or to repeat the UBT. Urinary protein was detected using a urine test strip.

RESULTS

The positive rates for the u-Ab test and UBT were 8.9% (71/795) and 5.5% (44/801), respectively. The u-Ab test showed 88.4% sensitivity and 95.7% specificity using UBT as a standard. In the final diagnoses, the u-Ab test showed 97.6% sensitivity, 96.5% specificity, 61.2% positive predictive value (PPV), and 99.9% negative predictive value (NPV). Of the 508 samples tested using a urine test strip, negative results were obtained for 450 subjects with a sensitivity of 90%, specificity of 97.9%, PPV of 66.7%, and NPV of 99.5%. Proteinuria was detected in 58 samples, with a sensitivity of 100%, specificity of 88.9%, PPV of 40%, and NPV of 100%.

CONCLUSIONS

The u-Ab test is highly accurate and suitable for detecting H. pylori infection. However, the occurrence of proteinuria may yield false-positive results.

Nationwide survey of Helicobacter pylori treatment for children and adolescents in Japan

BACKGROUND

To prevent gastric cancer, a test-and-treat strategy for Helicobacter pylori has been proposed. This retrospective study assessed the clinical features, efficacy and safety of treatment for H. pylori infection in children and adolescents.

METHODS

Questionnaires concerning the clinical features and treatment of H. pylori in children and adolescents were sent to doctors in 2013. It included questions on patient background, H. pylori-associated disease, first- and second-line treatment, success or failure of eradication, resistance to antibiotics, and occurrence of adverse events. In 2014, serious adverse events associated with treatment were analyzed.

RESULTS

Invitation letters and questionnaires were sent to 1097 doctors, of whom 409 (37.3%) participated. Finally, 332 patients (mean age, 11.6 ± 3.4 years; male, n = 200) treated from 1997 to 2013 were analyzed. H. pylori-associated gastritis, iron deficiency anemia, and duodenal ulcer occurred most frequently. Success rates for first- and second-line treatments were 73.1% and 79.6%, respectively. Seventy-six H. pylori strains were analyzed for resistance to amoxicillin (AMPC) and clarithromycin (CAM), and 64 were analyzed for resistance to metronidazole (MNZ). CAM resistance was most frequent, occurring in 43.4% of patients; that of MNZ was 21.9%. Adverse events were observed in 13.8% of cases. In total, 587 cases of H. pylori infection were analyzed and no serious adverse events were observed.

CONCLUSIONS

Treatment for H. pylori in children and adolescents is safe, but further studies on treatment regimens should be conducted to improve eradication rates and monitor increasing CAM resistance.

Identification of Helicobacter pylori and the evolution of an efficacious childhood vaccine to protect against gastritis and peptic ulcer disease

Establishment of Helicobacter pylori infection as an etiologic agent of peptic ulcer disease and other gastric pathologies marked a revolution in gastroenterology which spurred an enormous interest in gastric physiology and immunology research. The association was soon also demonstrated in children as well. Application of antimicrobial therapies have proven remarkably efficacious in eradicating H. pylori and curing pediatric patients of duodenal ulcers as well as gastritis, negating a lifetime of ineffective therapy and life-threatening disease. Countries with high H. pylori prevalence and where H. pylori associated gastric cancer remains a primary cause of death due to cancer however would benefit from childhood vaccination. Studies in rodents and humans utilizing oral vaccination with bacterial exotoxin adjuvants demonstrated potential for limiting H. pylori colonization in the stomach. Almost 25 y of vaccine research recently culminated in a phase III clinical trial of over 4,000 children aged 6-15 y old to test an oral vaccine consisting of the H. pylori urease B subunit genetically fused to the E. coli heat labile toxin. Vaccination was demonstrated to have an efficacy of over 70%. Vaccination may now serve as an effective strategy to significantly reduce H. pylori associated disease in children throughout the world.

A Strategy for Helicobacter Immunohistochemistry Utilization in Pediatric Practice: Insights From Morphologic and Cost-Benefit Analyses

OBJECTIVES

Recent studies in adults have examined the utility of immunohistochemistry (IHC) in detecting Helicobacter in gastric biopsy specimens and reached differing conclusions. Dedicated cost-benefit analysis of Helicobacter IHC in pediatric gastric biopsy specimens has not been performed.

METHODS

From 1,955 pediatric gastric biopsies in a 1-year period, we identified 63 Helicobacter -positive and 120 Helicobacter -negative biopsy specimens. All cases were scored according to the Updated Sydney System for the severity of inflammation.

RESULTS

We observed that pediatric Helicobacter infection was significantly associated with germinal center formation, active inflammation, oxyntic mucosa with moderate to severe chronic inflammation, and antral mucosa with any chronic inflammation, exclusive of mild and superficial chronic inflammation. At least one associated pattern was seen in each Helicobacter -positive biopsy specimen. In comparison with adults, pediatric Helicobacter -positive biopsy specimens are more likely to lack acute inflammation and more likely to show moderate to marked chronic inflammation.

CONCLUSIONS

We recommend performing Helicobacter IHC on pediatric gastric biopsy specimens with any of the above inflammatory patterns. This approach can sensitively identify pediatric patients with Helicobacter gastritis, limit IHC staining to approximately 30% of all gastric biopsy specimens, and reduce costs by up to $55,306.90 per 1,000 biopsy specimens.

Helicobacter pylori infection in Omani children

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most common chronic bacterial infection in humans. Its prevalence in Omani adults and children is not known.

OBJECTIVE

To report histology-based H. pylori infection prevalence in Omani children.

METHODS

A retrospective study of biopsy proven H. pylori infection in children over a 3 year period in a single center. Age, gender, indication for endoscopy, history of recurrent abdominal pain, and anemia were compared between H. pylori-positive and negative children.

RESULTS

Of 143 patients who underwent endoscopy, gastric biopsies were available on 112. The overall prevalence of biopsy proven H. pylori infection was 25%. The prevalence in children with recurrent abdominal pain was 30% compared to 22% in children who underwent endoscopy for other indications (p = .382). The prevalence increased from 7% in children aged <5 years, to 33% in those aged between 5 and 10 years (p = .010). There was no significant difference in the prevalence between the 5-10 years age group (33%) and older age group (29%) (p = .814). There was no significant difference in gender or anemia between the two groups.

CONCLUSIONS

This study represents the first reported study on the prevalence of biopsy proven H. pylori infection in Omani children. H. pylori infection prevalence is 25%, is lower than regional and many Arab countries. The prevalence appears to increase till age of 5 years. There was no significant association between H. pylori and recurrent abdominal pain, gender, or anemia.

Role of childhood infection in the sequelae of H. pylori disease

The persistence of Helicobacter pylori infection plays a fundamental role in the development of H. pylori-associated complications. Since the majority of infected persons acquire the bacteria during early childhood, an examination of the immunobiology of H. pylori infection in children compared with that of adults may help identify host factors that contribute to persistent infection. Therefore, we begin our review of the role of persistence in H. pylori disease with an assessment of the clinical features of H. pylori infection in children. We next review the bacterial factors that promote colonization and evasion of host defense mechanisms. We then focus our attention on the early host immunological factors that promote persistence of the infection and its complications in humans and mouse models. We also highlight topics in which further research is needed. An examination of how immunological factors cause divergent manifestations of H. pylori infection in children compared with adults may provide new insight for therapeutic modification or prevention of persistent H. pylori infection and its complications.

Diagnostic accuracy of urine-based kits for detection of Helicobacter pylori antibody in children

BACKGROUND

Rapid urine-HpAb is reported to be a reliable test of Helicobacter pylori infection in adults, but there are no data on the application of the test in children. The aim of this study was to evaluate the accuracy of a urine-based enzyme-linked immunosorbent assay (urine-HpELISA) and immunochromatography (rapid urine-HpAb) kit for anti-H. pylori immunoglobulin G antibody in children. We compared its sensitivity and specificity in reference to the (13) C-urea-breath test (UBT) and H. pylori stool antigen test (HpSA).

METHODS

In total, 101 Japanese children without significant upper-abdominal symptoms were included (mean age, 7.1 years; range 2-15 years). Their sensitivity and specificity were evaluated in reference to the UBT and HpSA.

RESULTS

Thirty-seven children were judged H. pylori-positive and 64 negative by the UBT and HpSA. No discrepancy in the results was observed between UBT and HpSA. Urine-HpELISA showed 91.9% sensitivity and 96.9% specificity with an accuracy of 95.0%. Rapid urine-HpAb showed 78.4% sensitivity and 100% specificity with an accuracy of 92.1%. Seven false negative results for rapid urine-HpAb were from children aged younger than 10 years, and their antibody titers of urine-HpELISA were lower than true positives.

CONCLUSIONS

For the diagnosis of H. pylori infection in Japanese children, both tests are non-invasive, inexpensive, reliable and easy-to-perform methods giving satisfactory accuracy, although the sensitivity of the rapid urine-HpAb kit was inferior to that of the urine-HpELISA kit, especially in children aged younger than 10 years, showing relatively low titer of H. pylori antibody.

Upper gastrointestinal histopathological findings in children and adolescents with nonulcer dyspepsia with Helicobacter pylori infection

OBJECTIVES

The aim of the study was to investigate the histopathological lesions in the upper gastrointestinal mucosa associated with Helicobacter pylori infection in children with nonulcer dyspepsia.

METHODS

A cross-sectional case-control study was performed on 185 Brazilian children and adolescents (4-17 years, mean 9.5 ± 2.7 years), 63.2% girls, submitted to upper gastrointestinal endoscopy. The histopathological lesions of the esophageal and gastric mucosa were analyzed in biopsy samples.

RESULTS

H pylori infection was identified in 96 children (51.8%). Moderate to severe chronic active gastritis was present in antrum (70.5%) and corpus (45.2%), with higher grading in antrum than in corpus (P < 0.05). The topographic distribution of inflammation was pangastritis (61.9%), followed by antral (32.1%) and corpus (5.9%). H pylori density was higher in antrum than in corpus. Intestinal metaplasia was not found in the H pylori-infected group, nor was significant gastric atrophy. The scores for esophagitis were significantly higher (P < 0.05) in the noninfected group (1.4 ± 0.8) than in the H pylori-infected group (1.07 ± 0.9), with significant negative correlation (r = 0.29; P < 0.05) with the scores of gastric inflammation.

CONCLUSIONS

The prevalence of H pylori infection was high among children with dyspepsia and associated with moderate/severe degrees of gastric inflammation. The high scores of esophagitis in the noninfected group point to 2 distinct groups of pathological conditions sharing similar clinical patterns.

The role of Helicobacter pylori infection in gastro-oesophageal reflux in Iranian children

BACKGROUND

The relationship between Helicobacter pylori and gastro-oesophageal reflux disease (GORD) in children is controversial.

AIM

To determine the role of H. pylori infection and GORD in children living in a region which is endemic for H. pylori infection.

METHODS

A cross-sectional study was undertaken in 263 children aged 3-18 years, all of whom had symptoms of GORD and underwent upper gastro-intestinal endoscopy. H. pylori status was determined by conventional rapid urease test and Giemsa staining of antral and cardiac biopsies. Biopsies of the oesophagus and gastric mucosa were obtained from the lower oesophagus, the antrum and cardia according to standard protocol.

RESULTS

Of the 263 patients, 81 (31·5%) had GORD and 162 (61·5%) had gastritis. There were 59 H. pylori-infected patients (22·4%) and 204 were uninfected. H. pylori infection was detected in 52 (88·1%) of the antral and 10 (1·9%) of the cardiac biopsies. Three (5·1%) of the biopsies revealed infection of both antrum and cardia and in seven (11·8%) only the cardia was infected. The prevalence of H. pylori infection among patients with GORD (13/83, 15%) was significantly lower than in those without GORD (46/180, 26%) (OR 0·54, CI 0·27-0·93, p<0·05). The prevalence of H. pylori infection among those with gastritis (48/162, 30%) was significantly higher than in those without gastritis (11/101, 10·8%) (OR 3·44, CI 1·69-7·015, p<0·001).

CONCLUSION

H. pylori infection might protect against GORD.

Helicobacter pylori infection among a pediatric population with sickle cell disease

OBJECTIVES

Recurrent abdominal pain (RAP) is a common presenting symptom in children with sickle cell disease (SCD). This may be as a result of complications of the disease, surgical problems, or Helicobacter pylori gastritis. The prevalence of H pylori infection in SCD children is not known. This study aimed to determine the prevalence and association of H pylori infection with RAP in SCD children.

METHODS

This was a prospective case-control study conducted at the Lagos State University Teaching Hospital, Nigeria, involving SCD children (subject, n = 118) and non-SCD children (control, n = 118) matched for age, sex, and socioeconomic status. Seroprevalence status of the children was determined by measuring immunoglobulin G antibodies against H pylori using enzyme-linked immunosorbent assay that had been validated for pediatric use.

RESULTS

The overall prevalence of H pylori infection was 155 of 236 (SCD, 67.8%; non-SCD, 63.6%; OR, 1.1; 95% CI, 0.89-1.28; p = .493). The prevalence increased with age in both SCD and non-SCD children and was significantly highest at the age of 6 to 10 years (p < .001 in each case). H pylori infection was significantly associated with socioeconomic status of the parents (OR, 4.25; 95% CI, 1.49-12.1; p = .004) but not significantly associated with RAP in SCD children (OR, 1.21: 95% CI, 0.55-2.66; p = .632).

CONCLUSIONS

Prevalence of H pylori infection is high in SCD and non-SCD children in Lagos, Nigeria. There was no significant association between H pylori infection and recurrent abdominal pain in SCD children.

Impact of H. pylori on growth: is the infection or mucosal disease related to growth impairment?

BACKGROUND

Helicobacter pylori (H. pylori) has been recognized as one of the most common chronic bacterial infections in the world. Most children are colonized in early childhood, and the infection will last a lifetime unless the child is treated with appropriate antibiotics.

AIM

To evaluate whether H. pylori infection has an influence on growth and whether the severity of endoscopic findings relates to the growth impairment.

METHODS

We formed four groups based on the presence or absence of H. pylori infection and gastrointestinal complaints as follows: group I: RAP +/H. pylori+; group II: RAP +/H. pylori-; group III: RAP -/H. pylori+; group IV: RAP -/H. pylori-. The relationship between endoscopic appearances, histological severity of gastritis, and antral H. pylori density with growth parameters was evaluated.

RESULTS

The BMI standard derivation scores of groups I and II were significantly lower than those of asymptomatic controls independent of their H. pylori status. A significant difference in height for age standard derivation scores was observed only between groups I and IV. When we compared the BMI and height for age standard derivation scores of group III and group IV combined with that of the endoscopically normal children in the recurrent abdominal pain group, there was no significant difference between the two groups.

CONCLUSION

Recurrent abdominal pain associated with gastric mucosal injury plays a role in a decrease in BMI independent of H. pylori infection. However, if recurrent abdominal pain originates from H. pylori infection, it appears that linear growth is also affected.

Endoscopic identification of Helicobacter pylori gastritis in children

AIM

The role of endoscopic findings in deciding whether to biopsy the gastric mucosa of children remains unclear. The present study attempted, for the first time, to identify the value of endoscopic features for diagnosis of Helicobacter pylori (Hp) infection in children.

METHODS

Hp status of consecutive children receiving esophagogastroduodenoscopy (EGD) was established by combinations of histology, (13)C-urea breath test, and serum Hp immunoglobulin (Ig)G antibody. After routine EGD using a conventional endoscope, the presence of RAC (regular arrangement of collecting venules) was scored by close observation, which was carried out at two sites of lower corpus lesser curvature and upper corpus greater curvature. RAC-positive was defined as the presence of minute red points in a regular pattern. Antral nodularity was also scored as present/absent.

RESULTS

Eighty-seven consecutive children (38 boys, median age 13 years, range 9-15 years) were evaluated; 25 (29%) were Hp positive. Antral nodularity was seen in 21 (84%) all of whom were Hp positive. The RAC-negative pattern based on examination of the upper and lower corpus yielded a sensitivity, specificity, positive predictive value and negative predictive value for the presence of Hp infection of 100%, 90%, 81%, and 100%. Magnifying endoscopy confirmed that the RAC pattern corresponded to collecting venules in the gastric corpus.

CONCLUSIONS

The absence of RAC pattern suggests that gastric mucosa biopsies should be taken despite otherwise normal-appearing gastric mucosa for the diagnosis of Hp infection in children.

Prevalence of Helicobacter pylori infection in high-school students on Lanyu Island, Taiwan: risk factor analysis and effect on growth

BACKGROUND/PURPOSE

The Yami inhabit Lanyu Island and are the smallest and most primitive aboriginal tribe in Taiwan. Lanyu Island is a closed environment and little information is available on the prevalence of Helicobacter pylori infection there. This study aimed to establish the prevalence of H. pylori infection in high-school students on Lanyu Island and its risk factors and effect on growth.

METHODS

A cross-sectional population-based study was conducted among high-school students to determine the prevalence of H. pylori infection by using the 13C urea breath test. A questionnaire was administered to the recruited population. Relevant personal and socioeconomic data for risk factors of infection were collected. Body height and weight of the recruited adolescents in relation to H. pylori infection were analyzed.

RESULTS

A total of 106 high-school students (55 boys and 51 girls), with a mean age of 14.3 +/- 1.4 years were enrolled. The overall prevalence of H. pylori infection was 54.7%. Those residing in Dongcing village had the highest rate of H. pylori infection (73.3%). There was no difference in the prevalence of H. pylori infection according to sex, ethnicity, socioeconomic level or parental education. Sixty-two students (54.8%) were completely asymptomatic and the others had at least one gastrointestinal symptom. H. pylori infection was asymptomatic in 56.8% and symptomatic in 53.2% of students. There was no significant difference between infected and uninfected children with regard to body weight, height and body mass index.

CONCLUSION

The prevalence of H. pylori infection is high among high-school students on Lanyu Island. There is no evidence that infection is related to growth failure.

In French children, primary gastritis is more frequent than Helicobacter pylori gastritis

The aim of this study was to analyze the histological characteristics according to the updated Sydney classification (intensity of gastritis, degree of activity, gastric atrophy, intestinal metaplasia, and Helicobacter pylori) in symptomatic children referred for upper gastrointestinal endoscopy. A 4-year retrospective descriptive study was carried out in 619 children (282 females and 337 males), median age 3.75 years (15 days to 17.3 years) referred for endoscopy. Six gastric biopsies were done (three antrum and three corpus) for histological analysis (n = 4), direct examination and H. pylori culture (n = 2). H. pylori status was considered positive if at least two out of three tests were positive and negative if all three tests were negative. The results showed that only 66 children (10.66%) were H. pylori positive. Histological antral and corpus gastritis was detected in, respectively, 53.95% and 59.12% of all cases, most of them of mild grade 1. Antral and corpus activity was grade 1 in 18.57% and 20.03% of cases. H. pylori-positive versus H. pylori-negative children did differ in terms of moderate and marked histological gastritis and grade 2 or 3 activities. One girl had moderate gastric atrophy and another one moderate intestinal metaplasia, both being H. pylori negative. The findings indicate that primary antrum and corpus gastritis is 5.3 and 6.9 times, respectively, more frequent than H. pylori gastritis in French children, with usually mild histological gastritis and activity. Gastric atrophy and intestinal metaplasia are rare.

Helicobacter pylori infection in children

Helicobacter pylori infection is a common problem in pediatric practice, and its acquisition is related with poor socioeconomic conditions. Although the organism is thought to be responsible for many diseases, only a handful of them have a direct causal relationship. At present, only a small number of children with well-defined clinical syndromes are benefited from testing and treatment. The treatment should include at least two antibiotics with a proton pump inhibitor.

Helicobacter pylori-positive versus Helicobacter pylori-negative idiopathic peptic ulcers in children with their long-term outcomes

OBJECTIVES

The aim of this study is to investigate the differences in the characteristics between Helicobacter pylori-positive and H pylori-negative primary ulcers in Chinese children.

PATIENTS AND METHODS

We conducted a retrospective review of children with primary peptic ulcers. Demographic data, clinical presentations, endoscopic features, histological findings, H pylori prevalence, and ulcer recurrences were studied.

RESULTS

Forty-three Chinese children with primary peptic ulcers were diagnosed over 8 years and were reviewed. There were 31 boys and 12 girls (median age 12 years, range 3-16 years). Thirty children (70%) presented with acute gastrointestinal bleeding, whereas only 19 had a history of epigastric pain. Twenty-three patients (53.5%) were H pylori positive. H pylori-positive ulcers developed in older children (median age 12 vs 10 years, P<0.05) and affected more males (91.3% vs 50%, P<0.01) than the H pylori-negative group. The annual ulcer recurrence rates were estimated to be 5.2% (95% CI 4.2-6.3) and 11.4% (95% CI 9.1-13.6) for positive and negative groups, respectively (P<0.05). Multivariate logistic regression suggested H pylori-negative status and ulcer size >1cm were indepen-dent risk factors for recurrence.

CONCLUSIONS

Our report suggests that H pylori-negative primary ulcers exist in children with their own distinct features. In contrast to H pylori-positive ulcers, H pylori-negative ulcers develop in younger children, affect both sexes equally, and carry a higher recurrence risk.

Association between Helicobacter pylori infection in mothers and birth weight

Helicobacter pylori infection may cause intrauterine growth restriction (IUGR). However, it is unknown whether the growth of children from H. pylori-infected mothers is also affected or whether transmission of infection from mother to child occurs. This study aimed to determine if maternal H. pylori infection was associated with IUGR and low birth weight in a mouse model, and whether transmission of infection from mother to infant occurs. Female C57BL/6 mice were inoculated with H. pylori (n = 18) or water (control; n = 18) via gavage. Mice were mated at 6 weeks postinfection, with half of the mice sacrificed after 2 weeks of gestation. The remaining mice gave birth and a third of the litter was weighed and sacrificed at birth, during milk feeding (1.5 weeks), and during solid feeding (4 weeks). Stomachs of all mice and whole foetuses were cultured for the presence of H. pylori. There were no differences in litter size or foetus weight between control and H. pylori-infected mice. Pups from infected mothers had a lower weight during milk feeding (control, 5.91 +/- 0.23 g; H. pylori, 4.59 +/- 0.16 g; p < 0.05) and solid feeding (control, 12.73 +/- 0.58 g; H. pylori, 10.01 +/- 1.02 g; p < 0.05). H. pylori was not detected by culture in the pups at any age. H. pylori infection in mothers was associated with a decrease in infant weight during milk feeding and after weaning. Transmission of infection from mother to infant was not detected by culture, suggesting that decreased baby weight may be due to decreased milk supply or altered nutrition from the mother.

The association between Helicobacter pylori infection and height in children from an urban community in north-east Brazil

BACKGROUND

An association between Helicobacter pylori infection and short stature in children has been described recently.

AIM

To describe differences in stature between H. pylori-infected and non-infected children in a low-income community in north-east Brazil.

METHODS

H. pylori status was evaluated by 13C-urea-breath test; centile values for weight and height were calculated for each child.

RESULTS

The prevalence of H. pyloni was 55.8% (197/353) and increased with age. Of 197 H. pylori-positive children, 62% were below the 25th centile for height compared with 48% of H. pylori-negative children (75/156) [AOR (adjusted odds ratio) 1.61, 95% CI 1.04-2.49, p=0.03] after adjustment for variables with p < 0.25 in univariate analysis (gender, number of residents, of children per household and of persons per bed). These results were significant only when older children were included. Thus, in children aged 8-14 years, 80% (89/111) of H. pylori-positive were <25th centile for height compared with 63% (35/56) of H. pylori-negative children (p=0.01). Compared with children with a height >25th centile, the AOR for H. pylori infection increased from 2.42 in the crude analysis to 6.62 after adjustment (p=0.006).

CONCLUSIONS

H. pylori is associated with short stature in older children living in a poor urban community in Brazil.

Helicobacter pylori infection among children with gastrointestinal symptoms: a high prevalence of infection among patients with reflux oesophagitis

AIM

To investigate the link between H.pylori infection and dyspepsia in children, and association with reflux oesophagitis.

PATIENTS AND METHODS

H.pylori status was detected by rapid urease test and/or culture in 130 consecutive symptomatic children coming for upper gastrointestinal endoscopy: 40 - aged 8-12 years (55% boys); 90 - aged 13-18 years (21% boys). Endoscopic findings were analyzed. H.pylori prevalence in the age group 8-12 years was compared to the prevalence among 55 asymptomatic children, aged 7-12 years (13C-urea breath test).

STATISTICAL ANALYSIS

chi(2) test, Fisher's test, and logistic regression analysis.

RESULTS

The prevalence of H.pylori infection among patients with gastrointestinal symptoms was 54%. It was significantly higher among patients with reflux oesophagitis compared to patients with hyperaemic gastropathy: OR = 5.5; p = 0.03, 95% CI: 1.15-26.3. In logistic regression analysis, no significant difference between the prevalence of H.pylori infection between asymptomatic and symptomatic children could be demonstrated (OR = 1.8; 95% CI: 0.62-5.14).

CONCLUSIONS

The prevalence of H.pylori was significantly higher among patients with reflux oesophagitis compared to patients with hyperaemic gastropathy alone. Adjusting for age the prevalence of H.pylori infection was not higher among symptomatic children compared to asymptomatic children of the same age.

Helicobacter pylori: review of research findings

Helicobacter pylori attracted widespread interest from gastroenterologists because of its potential aetiologic role in disorders of the upper gastrointestinal tract. Based on extensive microbiological studies, Campylobacter pylori was renamed Helicobacter pylori, and the organism represents a new genus of bacteria. It is generally accepted that H. pylori causes chronic, non-specific gastritis (type B gastritis). The inflammatory response occurs even though the bacterium does not penetrate the gastric epithelium; it is found on the surface of and adjacent to the epithelium. The clinical significance of histological gastritis is unknown. The bacterium is often found in asymptomatic subjects. In Caucasian adults, the prevalence of infection increases with increasing age. Higher rates of infection are found in blacks and Hispanics than would be expected for their age. Whether these different rates are the result of racial or socioeconomic factors is not known. It is theorized, but not proven, that high rates of infection with H. pylori at an early age may explain the high incidence of gastric carcinoma found in Hispanic populations. H. pylori is found in almost every patient with duodenal ulcer disease, although no direct evidence for a causal relationship exists. Indirect evidence is based on the findings that if H. pylori infection is eradicated, ulcer recurrence is less likely (up to one year of follow-up). A small percentage of patients have a relapse despite eradication of the organism, suggesting a role for other factors in duodenal ulcer disease. The role of H. pylori in gastric ulcer disease is unknown. Seventy to eighty per cent of patients with gastric ulcer have evidence of H. pylori infection, and preliminary data seem to support the existence of two distinct aetiologic groups: those with gastric ulcers related to H. pylori infection and those with gastric ulcers related to use of non-steroidal anti-inflammatory drugs. The role of H. pylori in non-ulcer dyspepsia is unknown. Some clinicians believe that H. pylori causes non-ulcer dyspepsia and treat these patients for H. pylori infection. However, the data supporting this practice are poor. Treatment is only recommended for patients with resistant duodenal ulcers and patients who have frequent relapses of duodenal ulcers and who are willing to take triple-drug therapy (bismuth compounds, metronidazole, tetracycline) for the infection. As 95% of patients with duodenal ulcer have evidence of H. pylori infection, there is probably little need to confirm the diagnosis of H. pylori infection.

Association between hepatitis A virus and Helicobacter pylori in a developing country: the saga continues

BACKGROUND

The epidemiologic association between Helicobacter pylori and hepatitis A virus (HAV) has been evaluated by various different groups with conflicting conclusions. The aim of the present study was to determine the prevalence of HAV and H. pylori infection among adolescents attending high schools in Lebanon, and to identify the sociodemographic factors associated with their prevalence, individually and concurrently.

METHODS

Nine hundred and two school students 14-18 years of age were selected randomly from 30 schools scattered all over Lebanon and tested for IgG antibodies against hepatitis A and H. pylori. Each student received a copy of a self-administered questionnaire to be completed by his/her parents inquiring about demographics, history of immunization, and prior viral hepatitis illness in the student. Bivariate analysis examined the association between different sociodemographic variables and prior HAV or H. pylori infection, and multivariate regression analysis was done to determine the factors independently associated with prior infection.

RESULTS

Using ELISA the seroprevalence of antibodies against HAV was 71.3% as compared to 61.6% for anti-H. pylori. A total of 9.1% of those tested were negative for both agents. A multinomial regression analysis revealed that place of residence in relation to district or urban versus rural areas, in addition to mothers' education, were important determinants for the incidence of both agents.

CONCLUSION

The low number of subjects negative for both H. pylori and HAV antibodies in Lebanon is indicative of their high prevalence in the country. It is possible that this high prevalence reflects an age-specific prevalence rather than a true association.

Gastric histology, serological markers and age as predictors of gastric acid secretion in patients infected with Helicobacter pylori

BACKGROUND

Acid secretion is intimately associated with most upper gastrointestinal diseases. Helicobacter pylori infection is a major environmental factor modifying acid secretion.

AIM

To study the association between the pattern of H pylori gastritis and gastric secretory function in a large number of subjects without specific upper gastrointestinal disease.

METHODS AND MATERIALS

Maximal acid output (MAO) was measured in 255 patients with dyspepsia showing normal endoscopy. Activity and severity of gastritis, atrophy and H pylori infection were assessed in body and antral biopsies. The correlations of histological parameters as well as age, sex, height, weight, smoking, serum gastrin, pepsinogen I and II, and their ratio with MAO were determined. Multiple linear regression was used to show the best possible predictors of MAO.

RESULTS

Negative relationships: Body atrophy and body-combined (active and chronic) inflammatory scores showed a potent inverse correlation with MAO (correlation coefficients (CC) 0.59 and 0.50, respectively). Body:antral chronic gastritis ratio and body:antral combined inflammation ratio (both with CC = 0.49) and age (CC = 0.44) were also inversely correlated with MAO. Intestinal metaplasia at both antral and body sites had negative relationships with acid output with CC = 0.23 and 0.20, respectively. Positive relationships: Serum pepsinogen I, body H pylori density:combined inflammation ratio and pepsinogen I:II ratio with CC of 0.38, 0.38 and 0.30, respectively, correlated with MAO. The H pylori density: combined inflammation of both antrum and body positively correlated with MAO (CC = 0.29 and 0.38, respectively). Male sex and patient height also positively correlated with acid output. Modelling showed that body combined inflammatory score, body atrophy, age and serum pepsinogen I are independent predictors of acid output (R(2) = 0.62).

CONCLUSION

Combination of body gastritis, body atrophy, age and serum pepsinogen I can be used as predictors of acid-secretory state in populations infected with H pylori.

P53 genetic polymorphism of gastric cancer in Korea

BACKGROUND

Deletion or functional loss of the p53 tumor suppression gene plays a role in oncogenic transformation. The codon 72 polymorphism on exon 4 in the p53 gene produces variant proteins with either arginine (Arg) or proline (Pro), and is associated with an increased susceptibility of cancers of the lung, esophagus, breast, cervix and nasopharynx on a genetic basis. We designed this study to evaluate the influence of the p53 codon 72 polymorphism on gastric cancer in Korea.

METHODS

We extracted the peripheral blood samples in 84 patients with gastric cancer, 66 patients with H. pylori-associated chronic gastritis and 43 controls without H. pylori infection. PCR-RFLP analysis was performed to detect p53 codon 72 polymorphism in these patients.

RESULTS

There was no specific genotype of p53 polymorphism in the gastric cancer group compared to the other groups and no difference in genotypes by histologic subtypes. Classified by tumor location, Pro/Pro genotype was associated with an increase in proximal cancer and Arg/Arg genotype with distal cancer. As the frequency of p53 Arg allele increased, the cancer was of a more poorly differentiated type.

CONCLUSIONS

The specific genotype of p53 polymorphism seems to correlate with tumor location. Increased frequency of p53 Arg allele is associated with more poorly differentiated cancers.

Age-specific incidence of Helicobacter pylori

BACKGROUND & AIMS

Helicobacter pylori is most likely acquired in childhood, but the incidence of infection has not been determined prospectively by using an appropriate noninvasive test. The aim of this study was to determine the age-specific incidence of Helicobacter pylori infection in children and the risk factors for infection.

METHODS

Three hundred twenty-seven healthy index children between 24 and 48 months of age were enrolled over 15 months. At baseline, the Helicobacter pylori infection status of each index child and his or her older siblings and parents was assessed by using the carbon 13-urea breath test. All noninfected index children were then followed up with an annual carbon 13-urea breath test for 4 years to determine whether they became infected with Helicobacter pylori and, if so, the age at first infection. Information on potential risk factors was collected at baseline and each subsequent visit.

RESULTS

At baseline assessment, 28 of 327 (8.6%) index children were infected with Helicobacter pylori. The mean age of the 28 infected children was 32.78 months (SD, 5.14 months). Over the next 4 years, 279 index children not infected at baseline contributed 970 person-years of follow-up to the study. During this time, 20 children became infected with Helicobacter pylori. The rate of infection per 100 person-years of follow-up was highest in the 2-3-year age group (5.05 per 100 person-years of follow-up (95% confidence interval, 1.64-11.78) and declined progressively as children aged. Only 1 child became infected after 5 years of age. Having an infected mother, an infected older sibling, and delayed weaning from a feeding bottle (ie, after 24 months of age) were all risk factors for infection.

CONCLUSIONS

Children who become infected with Helicobacter pylori are infected at a very young age, and the risk of infection declines rapidly after 5 years of age. These findings have important implications for studies on the mode of transmission of infection.

Association between gastric atrophy and Helicobacter pylori infection in Japanese children: a retrospective multicenter study

The purpose of this study was to determine whether Helicobacter pylori infection and mucosal inflammation result in gastric atrophy in Japanese children. A total of 196 patients ages 1-16 years were retrospectively studied: 131 patients were infected with H. pylori and 65 patients were uninfected. Antral (n = 196) and corpus biopsy specimens (n = 70) were investigated based on the Updated Sydney system. In both the antrum and corpus, H. pylori-infected patients showed significantly higher degrees of inflammation and activity of gastritis, compared with noninfected patients. The prevalence of grade 2 or 3 atrophy in the antrum was 10.7% in H. pylori-infected patients and 0% in the noninfected patients (P < .01) and in corpus 4.3% and 0%, respectively (P = .20). The frequency of intestinal metaplasia in the 2 study groups was 4.6% and 4.6% in the antrum and 0% and 4.2% in the corpus, respectively. Among H. pylori-infected patients, the antrum showed significantly higher degrees of H. pylori density, inflammation and activity of gastritis, and atrophy than the corpus. In the antrum, atrophy was significantly correlated with activity, whereas in the corpus, atrophy correlated with H. pylori density, inflammation, and activity. H. pylori-induced gastric inflammation can cause atrophy in Japanese children, predominantly in the antrum. It remains to be determined whether H. pylori-infected children with gastric atrophy are at increased risk for gastric cancer.

The Nobel Prize in 2005 for the discovery of Helicobacter pylori: implications for child health

The Nobel Prize in Physiology or Medicine in 2005 has been awarded to B. Marshall and R. Warren for their discovery that peptic ulcer disease is caused by an infection with Helicobacter pylori. This infection, which affects about half of the world's population and is already extremely prevalent in adolescents in developing countries, starts as an asymptomatic gastritis which, under certain conditions, is followed by gastric or duodenal ulcer disease.

CONCLUSION

No proven benefit has yet been found by treating H. pylori-infected children with gastritis unless they have a peptic ulcer. Vaccination against H. pylori infection during early childhood is considered a means of preventing peptic ulcer disease and also possibly adenocarcinoma.

Trends in the prevalence of Helicobacter pylori in symptomatic children in the era of eradication

PURPOSE

Helicobacter pylori infection is common in Asia and is associated with dyspepsia, peptic ulcer, and gastric cancer. Eradication of the organism remains an important goal. Here, we looked at the trends in the prevalence of H pylori in symptomatic children over an 8-year period to assess the impact of an aggressive eradication program.

METHOD

A retrospective review was carried out between 1997 and 2004. All children with a history of dyspepsia or acute gastrointestinal bleeding were included and underwent gastroscopy. Three antral biopsies were taken during endoscopy and sent for histological analysis. Positivity of H pylori was treated aggressively with quadruple therapy under protocol. The demographic data, the histological findings, and the H pylori status were recorded.

RESULTS

There were a total of 159 patients (71 males, 88 females) who underwent gastroscopy in this period. One hundred nineteen patients showed histological evidence of gastritis, and the positive rate of H pylori was 25.6%. The overall prevalence has not decreased (33.3% in 1997, 27.7% in 2004). Increasing age, however, was associated significantly with the higher risk of H pylori infection.

CONCLUSION

H pylori has a high prevalence in Chinese children with increasing age. Eradication efforts seem to be unsuccessful in the reduction of prevalence. We hypothesize that this may be owing to cross-infection at meal times from sharing chopsticks.

Investigation of Helicobacter pylori infection in beta-thalassaemia major patients with recurrent abdominal pain

BACKGROUND

Recurrent abdominal pain (RAP) affects many children, especially those affected by beta-thalassaemia major. The role of Helicobacter pylori is still unclear in children with RAP.

OBJECTIVES

The aim of the present study was the comparison of beta-thalassaemia major patients and normal controls with RAP in H. pylori infection. The factors influencing H. pylori prevalence were also investigated.

METHODS

A series of 50 beta-thalassaemia major cases (30 female, 20 male; aged 6-25 years) and 50 age-matched and sex-matched controls, both presenting with RAP, were recruited during a period of 18 months. The study participants were obtained through a multistage random sampling method among those that met Apley's criteria. All the patients and controls had undergone diagnostic oesophagogastroduodenoscopy with biopsy. H. pylori infection was confirmed by two histopathological examinations on an endoscopy sample and a rapid urease test.

RESULTS

H. pylori infection in thalassaemic patients was more common than in controls [34/50 (68%) versus 30/50 (60%)], but this higher frequency was not statistically significant. A clear relationship was found between the prevalence of H. pylori and age, duration of transfusion/chelation programmes, pain duration and splenectomy. In contrast, H. pylori did not correlate with abdominal pain characteristics, blood group, serum ferritin level and pathology of the upper gastrointestinal tract. The most frequent endoscopy abnormality was gastritis (72%). Nausea and heartburn were the leading associated symptoms.

CONCLUSION

The high prevalence of H. pylori infection suggests that H. pylori should be remembered as a probable cause of RAP in beta-thalassaemia major patients.

Relevance of adjusted cut-off values in commercial serological immunoassays for Helicobacter pylori infection in children

We assessed the sensitivity and specificity of H. pylori IgG and IgA with a commercial immunoassay performed in Chile and a second non-commercial immunoassay performed in a reference laboratory in the United States, in serum of 80 children and adults referred for gastrointestinal endoscopies in a developing country. Overall, 56% of the patients were infected with H. pylori based on rapid urease test and staining techniques on gastric biopsies. When Receiver Operator Curves (ROC) were developed, the sensitivity and specificity were similar for IgG and IgA. Both immunoassays exhibited better specificity, positive and negative predictive value (NPV) in children than in adults when cut-off values were corrected according to the local population than when they were assessed using the cut-off values pre-defined in other populations. These results underline the need to establish more precise cut-off values corrected in the local populations where assessments of antibodies as diagnostic markers of H. pylori infection are planning.

Growth in children with Helicobacter pylori infection and dyspepsia

AIMS

To compare the height, weight, and body mass index (BMI) of children presenting with dyspeptic symptoms and Helicobacter pylori infection, to those with dyspepsia but without the infection.

METHODS

A retrospective chart review of 257 children was performed. 13C urea breath test was performed to detect H pylori infection; weight and height were recorded and BMI was calculated. Weight, height, and BMI SD scores were determined using the 1990 UK normative data. The Index of Multiple Deprivation 2004 (IMD 2004) scores, which measure deprivation at small area level, were calculated from the patients' postcodes.

RESULTS

Ninety seven of the 257 children were H pylori positive. The mean age at diagnosis and presenting symptoms of H pylori positive and negative patients were similar. The mean IMD 2004 scores for children with H pylori infection were significantly higher compared to H pylori negative patients, suggesting that children with the infection came from relatively more deprived areas. The mean weight and height SD score were significantly lower for children with H pylori infection compared to those without. However, this difference was no longer significant after adjusting for socioeconomic deprivation and ethnic differences between the groups.

CONCLUSION

Children with dyspepsia and H pylori infection were shorter and lighter than patients with similar symptoms but no infection. The differences in anthropometry may be due to socioeconomic and ethnic factors rather than H pylori infection.

Evaluation of stool antigen test for Helicobacter pylori infection in asymptomatic children from a developing country using 13C-urea breath test as a standard

OBJECTIVE

Prevalence of asymptomatic Helicobacter pylori infection is very high in infants and children in developing countries. C urea breath test (UBT) is a reliable non-invasive diagnostic test for H. pylori infection in children that avoids invasive endoscopy. We compared a newly introduced H. pylori stool antigen test (with a high sensitivity and specificity in symptomatic children) with UBT in asymptomatic children mostly 1-5 years old, from a population with a high prevalence of infection.

METHOD

Eighty six asymptomatic children (42 boys and 44 girls) were tested for H. pylori infection using the UBT and a stool antigen test (HpSA) based on a sandwich enzyme immunoassay for antigen detection.

RESULTS

Forty five of the eighty-six (52.3%) children tested positive for H. pylori using the breath test. In 34 of these forty-five children, H. pylori antigen was detected in stool (sensitivity = 75.6%, 95% CI = 63 to 88%). Of the 50 of 86 (58%) children positive by HpSA test, 34 were positive for breath test. Of the 41 children with negative UBT test 25 were negative for stool antigen test (specificity = 61%, 95% CI = 46 to 76%).

CONCLUSION

The sensitivity and specificity of the new stool antigen test are lower in asymptomatic children with high H. pylori prevalence rate compared to those reported for children with gastrointestinal symptoms. Its usefulness is limited for diagnosis in an asymptomatic child with H. pylori infection.

Helicobacter pylori status and symptom assessment two years after eradication in pediatric patients from a high prevalence area

OBJECTIVES

To establish the rate of Helicobacter pylori reinfection in children from an H. pylori high prevalence area, possible clinical features predictive of reinfection and the usefulness of re-treatment.

METHODS

65 consecutive children attending the authors' department between 1998 and 2000 who had proven successful H. pylori eradication were enrolled; 52 took part. Patients and family members were invited to undergo C-urea breath testing and to complete a simple questionnaire regarding symptoms and socioeconomic status. Patients with H. pylori reinfection were offered treatment; eradication was assessed by C-urea breath test 8 weeks after completion of treatment.

RESULTS

Of 52 children, 15 (28.8%) were H. pylori positive. Variables predictive of reinfection were age at primary infection and presence of an infected sibling. Although reinfected children were more frequently symptomatic than non-reinfected patients, no specific symptom was associated with reinfection. Of the nine re-treated patients who returned 8 weeks after completing therapy, the bacterium was eradicated in five (56%).

CONCLUSIONS

The 12.8% per year reinfection rate in childhood at 2 years that we observed should prompt a re-evaluation of H. pylori status even after a successful eradication. Living in an H. pylori high prevalence area increases the annual risk of reinfection by approximately fourfold over the annual risk in H. pylori low prevalence areas.

Comparison of invasive and non-invasive tests diagnosis and monitoring of Helicobacter pylori infection in children

BACKGROUND

There are few reports which the tests used for diagnosing Helicobacter pylori infection and monitoring its eradication in children.

STUDY AIMS

Prospective evaluation of invasive (gastric histology, rapid urease test [RUT]) and non-invasive (stool antigen [FemtoLab H. pylori], urea breath test [UBT]) tests in the diagnosis of H. pylori infection and post-treatment eradication in children and adolescents.

METHODS

Ninety-two patients (50 male, 42 female) referred for upper gastrointestinal endoscopy were prospectively enrolled. UBT was performed and stool specimens collected for monoclonal enzyme immunoassay for H. pylori antigen (FemtoLab) 1 to 4 days before endoscopy. H. pylori in gastric biopsies was evaluated by RUT and staining with hematoxylin-eosin and giemsa. Eradication therapy was given to children with abdominal pain and H. pylori gastritis. FemtoLab H. pylori and UBT were repeated 6 weeks after the end of triple therapy.

RESULTS

Histology identified H. pylori in 49 of 92 (53%) subjects. Concordance between histology and RUT was found in 78 of 92 children. FemtoLab H. pylori was positive in 41 of 78 (52.6%) children with sensitivity, specificity, positive and negative predictive values of 97.5%, 94.7%, 95.1% and 97.3%, respectively. For UBT, these values were 100%, 96.9%, 97.5% and 100%, respectively. Twenty-six of 36 patients who received triple therapy returned for eradication evaluation. Tests for H. pylori antigen in stool were positive in 10 of 26 and for UBT in 11 of 26.

CONCLUSION

Stool antigen (FemtoLab) and UBT were equally effective in diagnosing and confirming eradication of H. pylori infection in children.

Helicobacter pylori infection of human and murine primary gastric cells

The effect of Helicobacter pylori infection on human and murine primary gastric cells was determined. CagA was phosphorylated following adherence of H. pylori to primary human gastric cells. However, it did not adhere to human primary duodenal cells or murine gastric cells, and CagA could not be detected in cell lysates. Identification of an easily available animal model of infection in which the organism adheres to gastric mucosal cells would enhance studies of the virulence of H. pylori.

Age at acquisition of Helicobacter pylori infection: comparison of two areas with contrasting risk of gastric cancer

BACKGROUND

Helicobacter pylori infection is usually acquired during childhood and is a known risk factor for the development of gastric malignancies in adulthood. It has been reported that early age at first infection may determine a neoplastic outcome in adults. The purpose of this study was to determine the prevalence of Helicobacter pylori infection in children residing in areas with high (Pasto) and low risk (Tumaco) of gastric cancer in Colombia to evaluate whether differences in the age of acquisition of H. pylori infection were present in the two populations.

MATERIALS AND METHODS

The study sample was based on a census taken in 1999. Using the (13)C-urea breath test, we compared the prevalence of H. pylori infection among children aged 1-6 years.

RESULTS

Among 345 children in Pasto, 206 (59.7%) were H. pylori-positive, compared with 188 (58.6%) among 321 children in Tumaco. The two populations share a common pattern of very early age at infection and marked increase in prevalence during the first 4 years of life. No differences in any one year were observed when comparing the two groups.

CONCLUSIONS

The prevalence of infection was similarly high and increased with age in both populations. In these populations the age of acquisition of H. pylori after 1 year of age does not appear to be a primary factor responsible for the differences in the rates of gastric cancer incidence in adults. Previous findings in adults showed lower prevalence of the most virulent genotypes in Tumaco compared to Pasto, and bacterial virulence may play a key role in determining cancer outcome.

Discrimination of normal gastric mucosa from Helicobacter pylori gastritis using standard endoscopes and a single observation site: studies in children and young adults

BACKGROUND

In the Helicobacter pylori-negative normal stomach, collecting venules are visible in the gastric corpus as numerous minute points. This finding has been termed 'regular arrangement of collecting venules' (RAC). The aim of the present study was to investigate the reliability of the presence of the RAC pattern for discrimination of normal gastric mucosa from H. pylori gastritis in pediatric patients.

METHODS

Fifty-two consecutive children, adolescents and young adults (male:female 24 : 28; median age 15 years, range 8-29 years) referred for endoscopy and assessed for H. pylori infection were prospectively studied. The lower lesser curvature of the corpus near the incisura was evaluated for the RAC pattern using a standard endoscope with the tip close to, but not in contact with, the gastric surface. Gastric biopsies were taken after the endoscopic observation.

RESULTS

In all the 29 RAC-positive patients, active H. pylori gastritis was absent, whereas H. pylori gastritis was found in 20 of 23 RAC-negative patients (86.9%).

CONCLUSIONS

Identification of the RAC pattern at the lower lesser curvature of the corpus using close observation with a standard endoscope proved to be an effective and practical marker to discriminate normal histology from H. pylori gastritis among both children and young adults. Absence of the RAC pattern should prompt gastric mucosal biopsies despite otherwise normal-appearing gastric mucosa.

CagA antibodies as a marker of virulence in chilean patients with Helicobacter pylori infection

BACKGROUND

The bacterial and host factors that influence the clinical outcomes of the Helicobacter pylori infection have not been fully identified. Cytotoxin-associated gene product (CagA), one of the virulence factors, has been associated with a more aggressive form of infection. The authors studied the relationship between CagA status and clinical outcome in Chilean children and adults with H. pylori infection.

METHODS

One hundred eighty consecutive patients undergoing upper gastrointestinal endoscopic analysis were enrolled after informed consent was obtained. Rapid urease test and histologic analysis were used to detect H. pylori infection. IgA and IgG antibodies to H. pylori whole cell antigen preparation and IgG antibodies to CagA were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

H. pylori infection was detected in 42% of the patients by biopsy or urease test and in 38% and 20% of patients by IgG and IgA antibodies, respectively. The prevalence of H. pylori either by the invasive or the serologic tests was directly related to patient age. Among patients with H. pylori, there was no significant association between age and prevalence of CagA. Nearly 70% of the patients with H. pylori and peptic ulcer disease had CagA-positive strains. In contrast, only 49% of the patients with chronic gastritis alone had CagA-positive strains (P < 0.05).

CONCLUSIONS

In Chile, patients infected with H. pylori have a proportion of CagA-positive strains similar to that reported in developed countries. CagA prevalence was not significantly different in adults and children infected with H. pylori, suggesting that variations in clinical outcome may be related to host immune or environmental factors.

Impact of Helicobacter pylori infection on growth of children: a prospective cohort study

OBJECTIVE

The aim of this study was to prospectively follow a cohort of children without Helicobacter pylori infection and to compare growth velocity in the children who become infected during follow-up with that of children who remained infection-free.

METHODS

Three hundred forty-seven children in general good health, aged 12 to 60 months, who tested negative for H. pylori by the 13C-urea breath test, from three daycare centers in a lower-middle class borough of Cali, Colombia, were monitored for 2.5 years. Anthropometric measurements were performed every 2 months and breath tests every 4 months. Linear mixed models were used to analyze growth velocity in relation to onset of H. pylori infection.

RESULTS

One hundred five (30.3%) children who were uninfected at the start of the study became infected during follow-up. Growth velocity in infected children was reduced by 0.042 +/- 0.014 cm/mo (P = 0.003) (approximately 0.5 cm/yr) after adjusting for age. The rate of deceleration in growth velocity was relatively constant over time.

CONCLUSIONS

Among these lower-middle class children aged 12 to 60 months from a population with high prevalence of H. pylori infection, a new and sustained infection was followed by significant growth retardation.

New approaches to Helicobacter pylori infection in children

Helicobacter pylori infection is usually acquired during childhood, and evidence-based guidelines regarding diagnosis and treatment of infected children have been recently published. Diseases associated with H. pylori infection are gastritis, duodenal ulcers, mucosal-associated lymphoid-type (MALT) lymphoma, and gastric adenocarcinoma. The association of specific symptoms with H. pylori infection in children and adults (ie, recurrent abdominal pain and nonulcer dyspepsia) remains controversial. Additionally, the role of H. pylori in gastroesophageal reflux disease or in extra-gastrointestinal diseases (ie, coronary artery disease) lacks sufficient evidence to demonstrate causality. The diagnosis of H. pylori-associated diseases in children can reliably be made through gastroduodenal endoscopy with biopsies. Clinical trials are underway for the validation of noninvasive diagnostic tests for the H. pylori-infected child, and current guidelines recommend eradication therapy for infected children with duodenal and gastric ulcer, gastric lymphoma, and atrophic gastritis with intestinal metaplasia. The natural history of childhood H. pylori infection is poorly described. Moreover, rational approaches to the prevention and control of childhood H. pylori infection are critically needed, requiring characterization of the determinants for acquisition and persistence and the disease outcomes following eradication.

Quantitative evaluation of inflammatory and immune responses in the early stages of chronic Helicobacter pylori infection

The early consequences of Helicobacter pylori infection and the role of bacterial virulence determinants in disease outcome remain to be established. The present study sought to measure the development of host inflammatory and immune responses and their relationship to the putative bacterial virulence factors cag pathogenicity island (cagPAI), vacA allele, and oipA in combination with bacterial colonization density in a feline model of the early stages of H. pylori infection. Gastric tissues obtained from infected and uninfected cats were evaluated for H. pylori ureB, cagPAI, vacA allele, and oipA and colonization density (urease, histology, and real-time PCR). Inflammation was assessed by measuring mRNA upregulation of gamma interferon (IFN-gamma), interleukin (IL)-1 alpha, IL-1 beta, IL-4, IL-6, IL-8, IL-10, and IL-12 p40 and histopathology. The mucosal immune response was characterized by morphometric analysis of lymphoid follicles and by differentiating lymphocyte populations with antibodies against surface markers. Infecting H. pylori strains were positive for vacAs1 but lacked cagPAI and an active oipA gene. Colonization density was uniform throughout the stomach. Upregulation of IFN-gamma, IL-1 alpha, IL-1 beta, and IL-8 and increased severity of inflammatory infiltrates and fibrosis were observed in infected cats. The median number and total area of lymphoid aggregates were 5 and 10 times greater, respectively, in the stomachs of infected than uninfected cats. Secondary lymphoid follicles in uninfected cats were rare and positive for BLA.36 and B220 but negative for CD3 and CD79 alpha, whereas in infected cats they were frequent and positive for BLA.36, CD79 alpha, and CD3 but negative for B220. Upregulation of IFN-gamma, IL-1 alpha, IL-1 beta, and IL-8 and marked hyperplasia of secondary lymphoid follicles are early consequences of H. pylori infection in cats. The response appears to be similar to that of infected people, particularly children, can develop independently of the pathogenicity factors cagPAI and oipA, and is not correlated with the degree of colonization density or urease activity.

Expression of Helicobacter pylori vacuolating toxin in Escherichia coli

VacA is a secreted toxin that plays a role in Helicobacter pylori colonization of the stomach and that contributes to the pathogenesis of peptic ulcer disease. Studies of VacA structure and function have been hindered by the lack of an efficient system for expression and genetic manipulation of this toxin. In this study, we developed methodology for expression of a functionally active VacA toxin in Escherichia coli. We then used a high-throughput screen to analyze a library of mutant toxins with pentapeptide insertions and identified six mutants that lacked the capacity to induce vacuolation of HeLa cells. The capacity to analyze VacA in this heterologous-expression system should greatly facilitate efforts to elucidate the structure and function of this toxin.

Helicobacter pylori in children and adolescents: increase of primary clarithromycin resistance, 1997-2000

BACKGROUND

The authors evaluate the prevalence of Helicobacter pylori resistance in 117 children and demonstrate the changes over a 4-year period.

METHODS

In 117 children and adolescents, H. pylori-positive gastritis was revealed by diagnostic upper endoscopy. Biopsies from the antrum and body of the stomach were tested by histology, urease test, and culture. H. pylori was isolated using standard culture techniques, and susceptibility to amoxicillin, clarithromycin, and metronidazole was tested using the E-test (AB-Biodisk, Sweden).

RESULTS

Endoscopy revealed gastric ulcers in 2 of 117 subjects, duodenal ulcers in 6 of 117, and erosive gastritis or duodenitis in 23 of 117. Almost all patients showed antral nodularity. Histology always showed chronic gastritis with different degrees of activity. During the 4-year study period, the authors noticed an increase of primary clarithromycin-resistant H. pylori strains, from 14.3% to 27.6% (mean, 20.3%). Metronidazole resistance varied between 5% and 25%. No resistance to amoxicillin was found.

CONCLUSION

Eradication of H. pylori should take place only after testing of susceptibility. The general use of clarithromycin in children should be restricted to better-defined indications. Resistance to clarithromycin of H. pylori may also become a future problem for the treatment of adults.

Histopathology of gastritis in Helicobacter pylori-infected children from populations at high and low gastric cancer risk

Infection with Helicobacter pylori has been recognized as a cause of gastric carcinoma. Although the neoplasia is always detected in adults, the infection starts in childhood. It has been reported that early age at first infection is a determinant of gastric cancer risk. In this study, we examined the histopathology of the gastric mucosa in infected children from a population at high risk for gastric cancer (Pasto, Colombia) and compared it with that of a lower-risk population (New Orleans, LA). Gastric biopsies obtained from antrum and corpus were stained with hematoxylin and eosin and Steiner's silver method. Immunohistochemical stains were used to identify B lymphocytes (CD20), T lymphocytes (CD3 and CD8), macrophages (CD68), and polymorphonuclear neutrophil myeloperoxidase. Morphometric techniques were used to evaluate the immunohistochemical stains. In both populations, the inflammatory lesions were seen predominantly in the antrum. Compared with children from the lower-risk populations, children from the higher-risk population exhibited more severe polymorphonuclear neutrophil infiltration, stromal and intraepithelial lymphocyte infiltration, mucus depletion, and H. pylori colonization density. Regenerative activity was significantly more marked in the lower-risk population. Morphometric analysis of immunohistochemical stains showed increased representation of T lymphocytes and macrophages in the higher-risk population. Most T lymphocytes stained positive for CD8, a marker of suppressor/cytotoxic cells. B lymphocytes were relatively more abundant in the lower-risk population. The possibility that the aforementioned characteristics of H. pylori infection in children are related to cancer risk in adults is discussed.

Helicobacter pylori serology at diagnosis and follow-up of biopsy-verified infection in children

Data on the use of Helicobacter pylori serology in children are limited. We studied the serum antibodies of 105 H. pylori-infected children (median age 9.1 y, range 1.5-17.5 y) using an in-house enzyme immunoassay. At diagnosis of the biopsy-verified infection, IgG antibodies to H. pylori were elevated in 98/105 children (93%) but were at a normal level in 7 children, 5 of whom were < 5 y of age. Serum IgA antibodies to H. pylori were elevated in 40/105 children (38%). The levels of IgG and IgA antibody titers to H. pylori correlated with age (p < 0.001 and p < 0.02, respectively). IgG titers were reduced by > or = 50% in 85% (83/98; median follow-up 0.6 y) of children after therapy. In 56 such children eradication was verified by negative histology or urea breath test but I such child showed Helicobacters on histologic examination. Of the 15 children whose IgG titers dropped by < 50%, 7 were considered positive and 4 negative on the basis of histology or urea breath test. In 3 children, IgG titers returned to pretreatment levels 1 y after a 50% drop was seen. Serology is 1 alternative for monitoring H. pylori infection in children, although its sensitivity is lower in very young children. The length of follow-up needed after eradication, however, is unclear.

A population-based survey on gastrointestinal tract symptoms and Helicobacter pylori infection in children and adolescents

BACKGROUND

Helicobacter pylori infection is a frequent infection mainly acquired in childhood. Even if the infection is almost invariably associated with mild to severe gastro-duodenal lesions, no specific clinical picture has been identified. The aim of this study was to evaluate the presence of dyspeptic symptoms and their relationship with the presence of H. pylori infection in the first two decades of life.

MATERIALS AND METHODS

A school-population sample size of 808 subjects from 6- to 19-year-olds was investigated for the presence of gastrointestinal tract symptoms and evaluated by a 13C-urea breath test for H. pylori infection. The relationship between clinical findings and H. pylori infection was evaluated by chi2 statistic or Fisher's exact test, as appropriate.

RESULTS

Symptoms of dyspepsia were identified in 45% of subjects, while the picture of ulcer-like and dysmotility-like forms were present in 3-4%. H. pylori infection was demonstrated in 95 (11.8%) subjects, 49.5% of them without symptoms. Severe epigastric pain and ulcer-like dyspepsia were significantly associated with H. pylori infection, while recurrent abdominal pain or dysmotility-like dyspepsia were not.

CONCLUSIONS

Dyspeptic symptoms are frequent in children, and its association with H. pylori infection is more evident than with recurrent abdominal pain. The age at which the infection is acquired seems to be under 6 years of age.