Helicobacter pylori among siblings

Correspondence between Helicobacter pylori antibodies and urea breath test results in a US-Mexico birth cohort

The uncertain accuracy of methods for detecting Helicobacter pylori infection in young children complicates research on this infection in early life. The aim of the present report was to describe the correspondence between positive serology and positive urea breath test (UBT) in children followed from age 0 to 24 months in the Pasitos Cohort Study, conducted along the US-Mexico border at El Paso and Juarez. Children were recruited before birth during 1998-2000 and examined at target ages of 6, 12, 18 and 24 months. H. pylori infection was detected using an enzyme immunoassay for serum immunoglobulin G antibodies and the (13)C-urea breath test corrected for age-dependent variation in CO(2) production. Of 472 children, 125 had one or more positive UBT results and 46 had one or more positive serology results. The prevalence of H. pylori infection at target ages of 6, 12, 18 and 24 months was 7%, 14%, 16% and 19%, respectively, by UBT and 8%, 2%, 3% and 3%, respectively, by serology. Few (<1%) of those tested on both tests were positive on both at any age. Among UBT-positive children, 6% were concurrently seropositive and 6% became seropositive later. Because UBT positivity cut points were selected to minimise false positives, these results suggest that H. pylori infection occurred frequently in this cohort, but rarely produced detectable antibodies. For clinical or epidemiological investigations, serology should not be used as the sole method for detecting H. pylori infection in children aged 2 years or less.

Children of Helicobacter pylori-infected dyspeptic mothers are predisposed to H. pylori acquisition with subsequent iron deficiency and growth retardation

BACKGROUND

We tested whether Helicobacter pylori-infected dyspeptic mothers had a higher rate of H. pylori infection in their children, and whether such H. pylori-infected children were predisposed to iron deficiency or growth retardation.

MATERIALS AND METHODS

A total of 163 children from 106 dyspeptic mothers (58 with and 48 without H. pylori infection) were enrolled to evaluate body weight, height, hemoglobin, serum ferritin, and H. pylori infection using the 13C-urea breath test. A questionnaire was used to evaluate demographic factors of each child.

RESULTS

The rate of H. pylori infection in children with H. pylori-infected dyspeptic mothers was higher than that of children with noninfected mothers (20.5% vs. 5.3%; p<.01, OR: 4.6, 95% CI: 1.5-14.2). The rate of H. pylori infection in children elevated as the number of their H. pylori-infected siblings increased (p<.01). For children below 10 years of age, H. pylori infection was closely related to low serum ferritin and body weight growth (p<.05).

CONCLUSION

The children of H. pylori-infected dyspeptic mothers had an increased risk for such infection. The risk further increased once their siblings were infected. H. pylori infection in pre-adolescent children may determine iron deficiency and growth retardation.

Reinfection rate in children after successful Helicobacter pylori eradication

OBJECTIVES

This study was performed to determine the rate of Helicobacter pylori reinfection after its successful eradication in children living in Germany.

DESIGN

A total of 102 children (48 boys; 31 German and 71 other nationalities; age 1.8-18 years) with a negative (13)C-urea breath test 8 weeks after triple therapy were followed up by a (13)C-urea breath test every 6 months. The cohort included 11 children aged <6 years, 58 children aged > or =6 to 12 years, and 33 children > or =12 years.

RESULTS

The mean duration (+/- standard deviation) of follow-up was 15.5 +/- 11.9 months with a maximum of 4.9 years, representing 132 patient years. Only three children (aged 9.7-14.9 years, one German, two Turkish) tested positive at 6, 12, and 18 months, respectively. The calculated reinfection rate was 2.3% per person per year.

CONCLUSION

The risk of reinfection with H. pylori is low in children living in Germany. There is no evidence that the reinfection rate depends on the age, sex, or nationality of the child. The low reinfection rate indicates that it is unnecessary to screen or treat asymptomatic family members in order to prevent reinfection.

Limitations to carbon 13-labeled urea breath testing for Helicobacter pylori in infants

We determined the validity of the carbon 13-labeled urea breath test in young children. We found that although the 13C-labeled urea breath test had a specificity greater than 90%, borderline or false positive results occurred more frequently in children younger than 2 years compared with older children. False positive results may be caused by oral-urease-producing organisms because direct intragastric administration of 13C urea reduced the excess delta 13CO2. Care is urged in interpreting one positive 13C-labeled urea breath test in children younger than 2 years.

Infants differ from teenagers: use of non-invasive tests for detection of Helicobacter pylori infection in children

Reliable non-invasive tests that are feasible in early childhood are essential to the study of transmission of Helicobacter pylori, since most individuals get infected during the first years of life. New tests are validated by comparison with a "gold standard", but no single test for detection of H. pylori infection can be used as a fully reliable reference method. Therefore, concordant results of at least two biopsy-based tests (histology, culture, rapid urease test) are considered as the "gold standard". Most of the validation studies in children included only a few infants and toddlers, with low numbers particularly for H. pylori-infected individuals. Only when increasing numbers of patients were tested and separated into subgroups by age it became apparent that the accuracy of most tests is lower in young children if the same cut-off values are used as established for older children or adults. Therefore, statements such as "a test has been validated with good results in children" must be interpreted with caution, unless different age groups are considered with sufficient numbers of infected and non-infected children in each age group.

Evaluation of the Helicobacter pylori stool antigen test (HpSA) for detection of Helicobacter pylori infection in children

OBJECTIVE

Helicobacter pylori (H. pylori) infection is usually acquired in early childhood. Noninvasive methods for detection of H. pylori infection are required to study its incidence, transmission, and clearance. They should be easy to perform, inexpensive, and have a high diagnostic accuracy, especially in infants and toddlers. Both serology and the 13C-urea breath test (13C-UBT) do not fulfill all these requirements. The aim of this study was to evaluate a new enzyme immunoassay for detection of H. pylori antigen in stool (Premier Platinum HpSA, Meridian Diagnostics, Cincinnati, OH) in a large cohort of children and to compare it to invasive techniques and the 13C-UBT.

METHODS

HpSA was performed in 310 stool samples of 274 children divided into three groups. Group A consisted of 145 children and adolescents (0.5-19.8 yr, 66/145 <6 yr) who underwent upper endoscopy for various gastrointestinal symptoms. H. pylori status was defined by histology, culture, and rapid urease test from biopsies of the antrum and corpus. A 13C-UBT was performed in 133 of 145 children. Group B consisted of 22 patients (5.7-16.1 yr) who were retested with both noninvasive tests 8 wk after anti-H. pylori triple therapy. Group C consisted of 129 healthy infants and toddlers (0.9-3.1 yr) who were tested with the 13C-UBT. Children with discrepant or positive test results were retested after 2 and 12 months. Results of the HpSA were read at 450/620 nm by spectrophotometry. An optical density <0.100 was defined as negative, >0.120 as positive, and values between 0.100 and 0.120 were considered as equivocal.

RESULTS

In Group A, the HpSA gave false-negative results in five of 45 infected children and false-positive results in four of 100 noninfected children, whereas four patients (2.8%) showed equivocal results. In both infected and noninfected children, no relation between the optical density values and age was found. The 13C-UBT was correct in 132 of 133 children tested. In Group B, there was complete concordance between the HpSA and 13C-UBT: 19 children tested negative and three positive. In Group C, concordant results between the two noninvasive methods were found in 124 of 129 (96%) toddlers (122 negative and two positive). Retesting of five children with discrepant results revealed that, on initial testing, the HpSA was incorrect in two (one false-positive, one false-negative), and the 13C-UBT was incorrect in three (always false-positive).

CONCLUSIONS

In symptomatic children, the HpSA revealed a sensitivity of 88.9% (95% CI 77.3-96.3) and a specificity of 94.0% (88.1-97.7) compared to the 13C-UBT, 100% (94.0-100) and 98.9% (94.7-100), respectively. However, in healthy toddlers, the HpSA performed as well as the 13C-UBT with excellent concordance between the two noninvasive tests. There was no age dependency of the stool test results, and changing the cutoff would not have improved accuracy. Thus, the HpSA test seems suitable to monitor the success of anti-H. pylori therapy.