Helicobacter pylori infection in pediatrics

Helicobacter pylori Infection in Children. Antimicrobial Resistance and Treatment Response

BACKGROUND

The aim of this study was to determine the appropriateness of the recent recommendations for managing Helicobacter pylori infection in children in a university hospital in Southern Europe. Antimicrobial resistance and response to eradication therapy were also determined.

MATERIALS AND METHODS

The presence of H. pylori was studied in 143 children: by gastric biopsy culture (GBC), (13)C-urea breath test (UBT) and stool antigen immunochromatography test (SAIT) in 56 children; by GBC and UBT in 20, by GBC and SAIT in 18, and by GBC alone in 49. Antimicrobial susceptibility was determined by E-test. Infection was defined as a positive culture or positivity in both UBT and SAIT. Disease progression was studied in 118 patients. First evaluation of symptoms was carried out at 3-6 months after diagnosis and/or after treatment of the infection.

RESULTS

H. pylori was detected in 74 from the 143 children analyzed (100% GBC positive, 98.1% UBT positive, and 58.1% SAIT positive). The main symptom was chronic abdominal pain (n = 121). Macroscopic antral nodularity was observed in 29.7% of infected patients and in 5.8% of uninfected patients, respectively. Resistance to clarithromycin and metronidazole was found in 34.7 and 16.7%, respectively. Eradication when susceptible antimicrobials were used occurred in 78.7% (48/61) versus 37.5% (3/8) when the treatment included a drug with resistance (p = .024). In patients with recurrent abdominal pain, symptoms resolved in 92.9% (39/42) patients with HP eradication versus 42.9% (6/14) without HP eradication (p < .001).

CONCLUSION

Treated patients often failed to meet the criteria established in the guidelines for H. pylori diagnostic screening and treatment because most of them had only recurrent abdominal pain, but remission of their symptoms was associated with H. pylori eradication.

What do we know about benefits of H. pylori treatment in childhood?

Policy analysis shows that H. pylori test and treat strategies targeting adults at moderate to high risk of H. pylori-induced disease is likely to be cost-effective for preventing digestive diseases responsible for a large global disease burden. Little is known, however, about health benefits to children from eliminating this infection. We conducted a systematic review of the evidence regarding health benefits to children from treatment to eliminate H. pylori infection.   We systematically searched Ovid MEDLINE for pertinent review articles published through 2012. We excluded reviews focused on treatment efficacy and scrutinized reference lists of selected reviews to identify additional eligible reviews. Fifteen reviews met specified inclusion criteria. Overall, they show that few reported studies investigating pediatric health effects of treatment for H. pylori infection were well designed with adequate statistical power. Thus, there is insufficient evidence for drawing conclusions about health benefits to children from treatment to eliminate H. pylori infection.

Indications to upper gastrointestinal endoscopy in children with dyspepsia

OBJECTIVES

The objective of the study was to ascertain the appropriateness of indications for upper gastrointestinal (UGI) endoscopy in children with dyspepsia.

METHODS

We used the RAND/University of California at Los Angeles method to investigate the appropriateness of the opinions of a panel of experts. The panel judged 2304 theoretical patient scenarios defined by a combination of demographic and clinical variables. Descriptive and multivariate logistic regression analyses were performed.

RESULTS

The panel rated UGI endoscopy as appropriate in 27.2% of cases, inappropriate in 14.3%, and dubious in 58.5%. Disagreement emerged for 21% of cases. UGI endoscopy was considered increasingly appropriate in cases with a positive family history of peptic ulcer and/or Helicobacter pylori infection (odds ratio [OR] 8.518, P < 0.0001), when dyspepsia interfered with activities of daily living ("sleep" OR 7.540, P < 0.0001; "normal activities" OR 5.725, P < 0.0001), and when patients were older than 10 years ("<or=10 years" OR 0.310, P < 0.0001) the longer the duration ("0-2 months" OR 0.002, P < 0.0001; "3-5 months" OR 0.059, P < 0.0001; "6-11 months" OR 0.516, P = 0.0005) and the greater the severity ("mild" OR 0.002, P < 0.0001; "moderate" OR 0.013, P < 0.0001) of their dyspeptic symptoms.

CONCLUSIONS

UGI endoscopy is not appropriate for all children with dyspeptic symptoms, but only for cases with a family history of peptic ulcer and/or Helicobacter pylori infection, older than 10 years of age, with symptoms persisting for more than 6 months and severe enough to affect activities of daily living.

Comparative genomics of Helicobacter pylori

Genomic sequences have been determined for a number of strains of Helicobacter pylori (H pylori) and related bacteria. With the development of microarray analysis and the wide use of subtractive hybridization techniques, comparative studies have been carried out with respect to the interstrain differences between H pylori and inter-species differences in the genome of related bacteria. It was found that the core genome of H pylori constitutes 1111 genes that are determinants of the species properties. A great pool of auxillary genes are mainly from the categories of cag pathogenicity islands, outer membrane proteins, restriction-modification system and hypothetical proteins of unknown function. Persistence of H pylori in the human stomach leads to the diversification of the genome. Comparative genomics suggest that a host jump has occurs from humans to felines. Candidate genes specific for the development of the gastric diseases were identified. With the aid of proteomics, population genetics and other molecular methods, future comparative genomic studies would dramatically promote our understanding of the evolution, pathogenesis and microbiology of H pylori.

[The role of Helicobacter pylori infection in children with chronic immune thrombocytopenic purpura]

Helicobacter pylori infection has been associated with immune thrombocytopenic purpura in adults, however, the few studies concerning this issue showed conflicting results in the paediatric field. Therefore, authors prospectively investigated the incidence of Helicobacter pylori infection and the effect of Helicobacter pylori eradication on platelet count recovery in children with immune thrombocytopenic purpura.

PATIENTS AND METHODS

The study included 27 children with immune thrombocytopenic purpura (13 boys and 14 girls) with a median age of 8.2 years (range, 18 months-18 years). 38 healthy children (controls) were also enrolled (20 boys, 18 girls, median age, 9.6 years, range, 4-18 years). Helicobacter pylori infection was diagnosed using 13 C urea breath test. Eradication was assessed at 6 weeks following the end of the treatment by 13 C urea breath.

RESULTS

2 children out of 27 patients with immune thrombocytopenic purpura proved to be positive for Helicobacter pylori infection (7.7%) and were treated with combination therapy. Controls showed similar rate of Helicobacter pylori infection (3/38, 7.9%) in comparison to those with immune thrombocytopenic purpura. In the follow-up period (mean, 10 months, range, 6-14 months) platelets did not show any improvement in infected children following the eradication treatment and were identical to those of the uninfected patients. Eradication was successful in the 2 Helicobacter pylori infected patients with immune thrombocytopenic purpura.

CONCLUSION

The results do not suggest a pathogenetic role of Helicobacter pylori infection in the etiology of immune thrombocytopenic purpura. Screening of Helicobacter pylori infection among paediatric patients with immune thrombocytopenic purpura is not recommended.

Lack of diagnostic accuracy of the monoclonal stool antigen test for detection of Helicobacter pylori infection in young Australian aboriginal children

BACKGROUND

: The prevalence of Helicobacter pylori infection among Aboriginal Australians children is unclear. The aims of the present study are to determine the prevalence of H. pylori infection among young Aboriginal children recovering from acute diarrheal disease in hospital and to evaluate the H. pylori stool antigen test as a noninvasive diagnostic test in this setting.

METHODS

: This was a prospective comparative study using the C-Urea Breath Test as reference standard. Fifty-two children between 4 months and 2 years of age were consecutively enrolled. These children comprised a representative sample of Australian Aboriginal children admitted to hospital with acute diarrheal disease from remote and rural communities across Northern Territory of Australia.

RESULTS

: The overall prevalence of H. pylori was 44.2%. The stool antigen test had a sensitivity of 0.55 (95% confidence interval [CI]: 0.35-0.73) with a positive predictive value of 0.65 (95% CI: 0.42-0.82). The specificity was 0.68 (95% CI: 0.46-0.84) with a negative predictive value of 0.58 (95% CI: 0.39-0.75). Analysis of receiver operator characteristic curve yielded an overall accuracy of the stool antigen test of 61% (48%-75%).

CONCLUSIONS

: The prevalence of H. pylori infection among very young Aboriginal children from remote and rural communities was high and consistent with early acquisition. The diagnostic accuracy of the stool antigen test to diagnose H. pylori in this setting was poor.

Evaluation of two triple-therapy regimens with metronidazole or clarithromycin for the eradication of H. pylori infection in Vietnamese children: a randomized, double-blind clinical trial

BACKGROUND

Eradication of Helicobacter pylori infection in children in developing countries needs further investigations upon which to base treatment recommendations. The aim of the study was to compare two 2-week triple therapies in a randomized double-blind trial.

MATERIALS AND METHODS

In order not to exceed recommended dosages, the 238 H. pylori-infected children, aged 3 to 15 years (mean 8.6), were divided in two weight categories receiving at weights 13-22 kg: lansoprazole 15 mg once-daily and amoxicillin 500 mg twice-daily with metronidazole 250 mg twice-daily or clarithromycin 250 mg once-daily; at weights 23-45 kg: lansoprazole 15 mg and amoxicillin 750 mg with metronidazole 500 mg or clarithromycin 250 mg, all administered twice daily. H. pylori status was assessed by culture and a monoclonal-based antigen-in-stool test (Premier Platinum HpSA PLUS) and side effects by structured questionnaires.

RESULTS

The overall per-protocol eradication (n = 233) was similar in the two treatment regimens, 62.1% for the metronidazole and 54.7% for the clarithromycin-containing therapy. Eradication rate was higher in children >or= 23 kg (70.9%) than in children < 23 kg (45.7%). In children >or= 23 kg (n = 117) that received twice-daily administration of all drugs, efficacy of the metronidazole and clarithromycin-containing treatments were 69.5% and 72.4%, respectively.

CONCLUSIONS

The two treatments gave similar eradication rates. Significant differences for both treatments were found by weight, which could be the result of the once-daily proton pump inhibitor and clarithromycin and/or more antibiotic resistant strains in younger children.

Helicobacter pylori infection in children with celiac disease

OBJECTIVE

To analyze the prevalence of Helicobacter pylori (H. pylori) infection in children with celiac disease (CD) and to examine the role of H. pylori infection in clinical, laboratory and histopathological presentations of CD.

MATERIAL AND METHODS

Data on 96 children with CD and 235 children who underwent endoscopy were compared for the prevalence and gastric histology pattern of H. pylori. Clinical presentation, laboratory and histological findings of CD children with and without H. pylori infection were compared.

RESULTS

Twenty-one subjects (21.8%) in the CD group and 56 subjects (23.8%) in the control group had H. pylori gastritis. Gastric metaplasia is higher in CD patients with H. pylori gastritis (19%) than in patients without H. pylori gastritis (1.3%) and in the control group (3.5%) (p<0.05 for all groups). Abdominal distension is more common at initial admission in CD patients with H. pylori gastritis (57.1% versus 14.6%, p<0.05). No significant difference was found between H. pylori (+) and (-) CD patients in terms of prevalence of anemia, iron deficiency and iron-deficiency anemia. Only mild duodenal histological findings were more common in H. pylori patients (57.1% versus 26.7%, p<0.05).

CONCLUSIONS

CD may be associated with H. pylori gastritis, but it does not affect the clinical presentation of the disease, except for abdominal distension; CD is associated with mild duodenal lesions. A gluten-free diet improves the symptoms in all patients independently of the presence of H. pylori gastritis. Gastric metaplasia increases in the presence of H. pylori gastritis. Further prospective studies are needed to examine the clinical and histopathological outcomes of gastric metaplasia associated with H. pylori gastritis in CD patients.