The role of Helicobacter pylori in children with chronic idiopathic thrombocytopenic purpura

Impact of Helicobacter pylori Infection upon the Evolution and Outcome of Pediatric Immune Thrombocytopenic Purpura: A Comprehensive Review

In adults with immune thrombocytopenic purpura (ITP), the identification of H. pylori infection and its subsequent eradication proved to aid platelet recovery. Similar findings, at a smaller scale, were allegedly reported by some pediatric studies. This review's objective was to establish the influence of H. pylori infection and its eradication upon platelet count and recovery in pediatric ITP. Three databases, namely Pubmed, Scopus and Web of Science, were searched for pediatric studies which investigated a link between H. pylori infection and thrombocytopenia. The search results retrieved a number of 21 articles which complied to the inclusion and exclusion criteria. Some studies report lower platelet values among children with ITP and documented H. pylori infection, as well as an improve in platelet numbers after H. pylori treatment. However, results are controversial, as multiple authors failed to identify a higher prevalence of H. pylori among children with ITP or a lack of significant change in therapeutic outcome with the addition of an eradication regimen to standard treatment. The main limitations of current pediatric studies remain the small study samples and the short follow-up periods of the included subjects. Hence, the long-term impact of H. pylori in children with ITP is still uncertain.

Impact of eradication therapy of Helicobacter pylori in children with chronic immune thrombocytopenic purpura

Background

Although some investigators have confirmed the association between H. pylori and chronic ITP in adults, studies in pediatric patients are still few and have produced conflicting results. The study was carried out to detect the prevalence of H. pylori among chronic ITP children and to investigate the impact of treatment of H. pylori infection on platelet count response.

Results

The prevalence of H. pylori in chronic ITP children was 63%. The platelet count was statistically significantly higher among H. pylori stool antigen (HpSA)-negative children. A significant difference was reported in which platelet count increased from 70.55 ± 4.788 million/μL before H. pylori eradication therapy to 110.78 ± 15.128 million/μL after therapy.

Conclusion

We concluded that H. pylori eradication therapy was effective in increasing platelet count in H. pylori-positive chronic ITP patients.

Efficacy of Helicobacter pylori Eradication Therapy on Platelet Recovery in Pediatric Immune Thrombocytopenic Purpura-Case Series and a Systematic Review

Evidence relating to the efficacy of Helicobacter pylori eradication therapy for chronic immune thrombocytopenic purpura (cITP) in childhood is inadequate. The aim of this retrospective study was to determine the efficacy of H. pylori eradication therapy for platelet response in pediatric patients with cITP in our hospital, and to perform a systematic review of previous reports about pediatric patients with cITP who were positive for H. pylori infection and were treated with H. pylori eradication therapy. Analysis of the data of pediatric patients with cITP in our hospital and a systematic review of digital literature databases of studies in pediatric patients with cITP were performed. Data of 33 pediatric patients with cITP from our hospital records showed that the prevalence of H. pylori infection and the rate of response to platelet therapy were 15% and 33.3%, respectively. Data of 706 pediatric patients from 18 previous reports showed that the prevalence of H. pylori infection and rate of platelet response were 23% and 43.8%, respectively. Eradication therapy for H. pylori infection in pediatric cITP patients can be expected to result in a response equivalent to that in the adult population, with fewer adverse effects than other treatments for cITP.

Current views of the relationship between Helicobacter pylori and Henoch-Schonlein purpura in children

Helicobacter pylori (H. pylori) is one of the factors involved in the pathogenesis of various gastrointestinal diseases and may play a potential role in certain extra-intestinal diseases. H. pylori infection are mainly acquired during childhood, and it has been reported that in endemic areas of China the infection rates are extraordinarily higher in HSP children, particular those with abdominal manifestations. Furthermore, eradication therapy may ameliorate Henoch-Schonlein purpura (HSP) manifestations and decrease the recurrence of HSP. Therefore, results suggested that detection of H. pylori infection by appropriate method ought to be applied in HSP children. Current evidences indicate that local injury of gastric mucosa and immunological events induced by H. pylori infection are involved in the development of HSP. Increased serum IgA, cryoglobulins, C3 levels, autoimmunity, proinflammatory substances and molecular mimicry inducing immune complex and cross-reactive antibodies caused by H. pylori infection might play their roles in the course of HSP. However, there are no investigations confirming the causality between H. pylori infection and HSP, and the pathogenesis mechanism is still unclear. More bench and clinical studies need to be executed to elaborate the complex association between H. pylori and HSP.

Helicobacter pylori Eradication in Patients with Immune Thrombocytopenic Purpura: A Review and the Role of Biogeography

Idiopathic thrombocytopenic purpura (ITP) is typically a diagnosis of exclusion, assigned by clinicians after ruling out other identifiable etiologies. Since a report by Gasbarrini et al. in 1998, an accumulating body of evidence has proposed a pathophysiological link between ITP and chronic Helicobacter pylori (H. pylori) infection. Clinical reports have described a spontaneous resolution of ITP symptoms in about 50% of chronic ITP patients following empirical treatment of H. pylori infection, but response appears to be geography dependent. Studies have also documented that ITP patients in East Asian countries are more likely to express positive antibody titers against H. pylori-specific cytotoxic-associated gene A (CagA), a virulence factor that is associated with an increased risk for gastric diseases including carcinoma. While a definitive mechanism by which H. pylori may induce thrombocytopenia remains elusive, proposed pathways include molecular mimicry of CagA by host autoantibodies against platelet surface glycoproteins, as well as perturbations in the phagocytic activity of monocytes. Traditional treatments of ITP have been largely empirical, involving the use of immunosuppressive agents and immunoglobulin therapy. However, based on the findings of clinical reports emerging over the past 20 years, health organizations around the world increasingly suggest the detection and eradication of H. pylori as a treatment for ITP. Elucidating the exact molecular mechanisms of platelet activation in H. pylori-positive ITP patients, while considering biogeographical differences in response rates, could offer insight into how best to use clinical H. pylori eradication to treat ITP, but will require well-designed studies to confirm the suggested causative relationship between bacterial infection and an autoimmune disease state.

Immune thrombocytopaenic purpura: an autoimmune cross-link between infections and vaccines

Immune thrombocytopaenic purpura (ITP) is an autoimmune systemic disease detectable by the presence of low blood platelets count (<10(5)/µl) and the production of autoantibodies against glycoproteins expressed on the platelet surface. The clinical course is often acute, and life-threatening events may occur especially in children, with 52% of paediatric patients recovering either spontaneously or after treatment. A chronic ITP evolution is observed in 64% of adults, of whom 12% will develop an overlapping autoimmune disease. Several microbial agents such as CagA-positive Helicobacter pylori or Candida albicans and a number of viruses including CMV, EBV or HIV can potentially trigger ITP through molecular mimicry. Moreover, ITP improves after treatment of the underlying infection. Similarly, vaccines such as MMR may prompt ITP (IRR 5.48, 1.61-18.64, p < 0.006). Early recognition of the underlying microbial trigger and the removal of modifiable aetiopathogenetic factors should be integrated as a complementary treatment strategy in all patients who do not readily improve with standard ITP care.

Helicobacter pylori infection & immune thrombocytopenic purpura in children and adolescents: A randomized controlled trial

Helicobacter pylori and immune thrombocytopenic purpura (ITP) association is not well established in chronic ITP (cITP) in children, although the cure of thrombocytopenia in approximately half of H. pylori eradicated adult patients has been described. The aim of this study was to investigate the effect of H. pylori eradication on platelet (PLT) recovery in cITP children and adolescents through a randomized, controlled trial. A total of 85 children (mean age 11.4 years) with cITP were prospectively enrolled. Diagnosis of H. pylori was established by two locally validated tests, (13)C-urea breath test and monoclonal stool antigen test. Twenty-two infected patients were identified, and randomly allocated into two groups: H. pylori treatment group (n = 11) and the non-intervention control group (n = 11). The control group was offered treatment if the thrombocytopenia persisted after the follow-up. At baseline, there were no differences regarding age, sex, duration of disease, and PLT count between groups. Sixty three of 85 patients were uninfected. PLT response was classified as complete response: PLT > 150 × 10(9 )l(-1); partial response: PLT 50-150 × 10(9 )l(-1), or an increase of 20-30 × 10(9 )l(-1); no response: PLT < 50 × 10(9 )l(-1) or an increase of <20 × 10(9 )l(-1) after at least 6 months of follow-up. Complete response was observed in 60.0% (6/10, one excluded) H. pylori eradicated patients vs. 18.2% (2/11) in non-eradicated patients (p = 0.08; OR = 6.75) after 6-9 months of follow-up. Among uninfected patients, only 13.8% (8/58) presented complete response. Two non-treated controls were treated after 6-12 months of follow-up, and PLT response was observed in 61.5% (8/13) of H. pylori eradicated patients, and in 19.0% (11/58) of uninfected patients (p = 0.004). Cytotoxin associated gene A and vacuolating cytotoxin gene A IgG antibodies were present in almost all infected patients. Therefore, the study suggests that H. pylori eradication plays a role in the management of H. pylori infected cITP children and adolescents.

Helicobacter pylori infection and extragastric disorders in children: a critical update

Helicobacter pylori (H. pylori) is a highly prevalent, serious and chronic infection that has been associated causally with a diverse spectrum of extragastric disorders including iron deficiency anemia, chronic idiopathic thrombocytopenic purpura, growth retardation, and diabetes mellitus. The inverse relation of H. pylori prevalence and the increase in allergies, as reported from epidemiological studies, has stimulated research for elucidating potential underlying pathophysiological mechanisms. Although H. pylori is most frequently acquired during childhood in both developed and developing countries, clinicians are less familiar with the pediatric literature in the field. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae. A further clinical challenge is whether the progressive decrease of H. pylori in the last decades, abetted by modern clinical practices, may have other health consequences.

Helicobacter pylori-associated immune thrombocytopenia: Clinical features and pathogenic mechanisms

Immune thrombocytopenia (ITP) is an autoimmune disease mediated by anti-platelet autoantibodies. There is growing evidence that the eradication of Helicobacter pylori (H. pylori) effectively increases platelet count in a considerable proportion of ITP patients infected with this bacterium. In the majority of ITP patients responding to H. pylori eradication therapy, the anti-platelet autoantibody response is completely resolved with no relapse for more than 7 years, indicating that the disease is cured. Therefore, adult patients with suspected ITP should be examined for H. pylori infection, and eradication therapy is recommended if the infection is present. Notably, however, the efficacy of H. pylori eradication therapy in ITP patients varies widely among countries, with a higher response rate in Japan compared with the United States and European countries other than Italy. The pathogenesis of H. pylori-associated ITP is still uncertain, although the mechanisms are known to involve multiple factors. H. pylori may modulate the Fcγ-receptor balance of monocytes/macrophages in favor of activating Fcγ receptors, and H. pylori components may mimic the molecular makeup of platelet antigens. Further studies of the pathogenic process of H. pylori-associated ITP may be useful for the development of new therapeutic strategies for ITP.

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.

Evidence-based guidelines from ESPGHAN and NASPGHAN for Helicobacter pylori infection in children

OBJECTIVE

As the clinical implications of Helicobacter pylori infection in children and adolescents continue to evolve, ESPGHAN and NASPGHAN jointly renewed clinical guidelines using a standardized evidence-based approach to develop updated recommendations for children and adolescents in North America and Europe.

METHODS

An international panel of 11 pediatric gastroenterologists, 2 epidemiologists, 1 microbiologist, and 1 pathologist was selected by societies that developed evidence-based guidelines based on the Delphi process with anonymous voting in a final face-to-face meeting. A systematic literature search was performed on 8 databases of relevance including publications from January 2000 to December 2009. After excluding nonrelevant publications, tables of evidence were constructed for different focus areas according to the Oxford classification. Statements and recommendations were formulated in the following areas: whom to test, how to test, whom to treat, and how to treat. Grades of evidence were assigned to each recommendation based on the GRADE system.

RESULTS

A total of 2290 publications were identified, from which 738 were finally reviewed. A total of 21 recommendations were generated, and an algorithm was proposed by the joint committee providing evidence-based guidelines on the diagnostic workup and treatment of children with H pylori infection.

CONCLUSIONS

These clinical practice guidelines represent updated, best-available evidence and are meant for children and adolescents living in Europe and North America, but they may not apply to those living on other continents, particularly in developing countries with a high H pylori infection rate and limited health care resources.

Effect of eradication of Helicobacter pylori in children with chronic immune thrombocytopenia: a prospective, controlled, multicenter study

BACKGROUND

The eradication of Helicobacter pylori has been associated with remission of immune thrombocytopenia (ITP) in approximately half of eradicated patients. Data on children are limited to small case series.

PROCEDURE

Children from 16 centers in Italy, who were less than 18 years of age and diagnosed with chronic ITP (cITP), were screened for H. pylori infection. Positive patients underwent standard triple therapy with amoxicillin, clarithromycin, and omeprazole. The eradication response was defined as follows: complete response, platelet (PLT) count ≥ 150 × 10(9) /L; partial response, PLT count of at least 50 × 10(9) /L; no response, PLT count <50 × 10(9) /L.

RESULTS

Of 244 screened patients, 50 (20%) had H. pylori infection, 37 of which received eradication therapy and completed follow-up. Eradication was successful in 33/37 patients (89%). PLT recovery was demonstrated in 13/33 patients after eradication (39%), whereas spontaneous remission was observed in 17/166 (10%) H. pylori-negative patients (P < 0.005). Responders more often required second line eradication (9/13), whereas a second cycle was required in 3/20 non-responders (P < 0.005).

CONCLUSIONS

Among the large cohort of patients, those who underwent successful H. pylori eradication showed a significantly higher PLT response. Therefore, it may be appropriate to look for H. pylori and eventually eradicate it in children with cITP.

Consequences of Helicobacter pylori infection in children

Although evidence is emerging that the prevalence of Helicobacter pylori (H. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. If untreated, H. pylori infection is lifelong. Although H. pylori typically colonizes the human stomach for many decades without adverse consequences, children infected with H. pylori can manifest gastrointestinal diseases. Controversy persists regarding testing (and treating) for H. pylori infection in children with recurrent abdominal pain, chronic idiopathic thrombocytopenia, and poor growth. There is evidence of the role of H. pylori in childhood iron deficiency anemia, but the results are not conclusive. The possibility of an inverse relationship between H. pylori and gastroesophageal reflux disease, as well as childhood asthma, remains a controversial question. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae.

Effect of Helicobacter pylori eradication on platelet count in children with chronic idiopathic thrombocytopenic purpura

Recent reports have suggested, particularly in adults, an association between Helicobacter pylori infection (HPI) and chronic idiopatic thrombocytopenic purpura (cITP) with improvement of platelet count after eradication therapy. We investigated the association of HPI and cITP and the effect of HP eradication therapy on thrombocytopenia in a population of 24 children of both sexes mean age 8.0+/-0.28 years (range 5.4-10.7 years), affected by cITP (PLT <or=50 x 10(9)/l) lasting more than 6 months. HPI was investigated by Helicobacter pylori stool antigens (HpSA). In eight out 24 patients (33.3%) HP infection was identified positive and bacterial eradication was successful following 7 days of triple therapy (amoxicillin, clarithromicin and proton pump inibitors). A follow-up of platelet count was performed for 1 year after HpSA detection. Six out eight patients (75%) had total recovery of platelet count during the first year after bacterial eradication (PLT before therapy 32.5+/-3.5 x 10(9)/l; after 1 year 275+/-106.06 x 10(9)/l) (P<0.05), two patients (25%) had partial recovery (PLT before therapy 30 x 10(9)/l, after 1 year 103.5 x 10(9)/l) although not reaching statistical significance (P>0.05). Non-significant differences were found in platelet count between infected and uninfected patients before eradication treatment (PLT 33.0+/-2.8 x 10(9)/l versus 34.0+/-5.75 x 10(9)/l) (P>0.05), while significant differences were observed after eradication therapy (PLT 315.0+/-7.07 x 10(9)/l versus 43.5+/-2.12 x 10(9)/l) (P<0.05). HP assessment should be performed in all cITP patients and eradication therapy should be attempted in positive cases.

Advances in understanding the association of Helicobacter pylori infection with extragastric diseases

Helicobacter pylori (H. pylori) infection is one of the most common human infections worldwide. It is associated with the development of a number of important upper gastrointestinal (GI) diseases such as chronic gastritis, peptic ulcer and gastric malignancy. At present, there is evidence that H. pylori infection probably plays a critical role in the development of some extragastric diseases. However, there is still controversy over such association. In this article, we will give an overview of the recent advances in understanding the association of H. pylori infection with extragastric diseases.

Absence of platelet recovery following Helicobacter pylori eradication in childhood chronic idiopathic thrombocytopenic purpura: a multi-center randomized controlled trial

OBJECTIVE

To investigate the effect of Helicobacter pylori eradication on platelet recovery in childhood chronic idiopathic thrombocytopenic purpura (ITP).

PATIENTS AND METHODS

A multi-center randomized controlled trial was conducted. Patients aged 4-18 years, diagnosed with chronic ITP, defined by platelet count below 100 x 10(9)/L lasting more than 6 months without identified causes, were enrolled and underwent (13)C-urea breath test for diagnosis of H. pylori infection. Patients who received prednisolone more than 0.5 mg/kg per day or received other platelet-enhancing therapy were excluded. Patients with H. pylori infection were randomized into two groups: treatment and control groups. Treatment group received a standard protocol for H. pylori eradication and repeated (13)C-UBT at 4-6 weeks to confirm successful therapy while the control group received no specific treatment. Monthly platelet count was monitored for 6 months in both groups. Primary outcome was platelet recovery, defined by platelet count over 100 x 10(9)/L for at least 3 months.

RESULTS

Of the 55 ITP children, 16 (29.1%) had H. pylori infection. There were no differences in age, sex, duration of disease, platelet count, and the dose of prednisolone between the treatment group (n = 7) and control group (n = 9). One patient in control group was withdrawn due to massive gastrointestinal bleeding requiring a high dose prednisolone. At 6 months, platelet recovery was demonstrated in one patient in the treatment group as well as one in the control group.

CONCLUSION

No beneficial effect of H. pylori eradication on platelet recovery in childhood chronic ITP was identified.

Extragastric manifestations of Helicobacter pylori infection: other Helicobacters

The finding that Helicobacter pylori is the main cause of gastritis and peptic ulcer disease has opened a new era in the gastrointestinal world. Today there is evidence that H. pylori may also play a role in different nongastric diseases, opening the new "extragastric manifestations of H. pylori infection" field. Concerning this, several studies have been published in the last year. The most convincing data arise from those investigating idiopathic thrombocytopenic purpura and sideropenic anemia, while there is also an increasing evidence for a possible association with atherosclerotic disease. Furthermore, the discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. In particular, several species have been studied for a potential role in different liver and intestinal diseases with interesting findings.