Chronic Idiopathic Thrombocytopenic Purpura In Childhood Research Articles

Interferon‐γ +874A/T and interleukin‐4 intron3 VNTR gene polymorphisms in Chinese patients with idiopathic thrombocytopenic purpura

The polarization of Th1/Th2 towards Th1 contributes to the pathogenesis of idiopathic thrombocytopenic purpura (ITP). Cytokines may play crucial roles in the pathogenesis of ITP. The purpose of this study was to investigate whether the interferon (IFN)-gamma +874(A/T) and interleukin-4 (IL-4) variable number of tandem repeats (VNTR) in intron3 polymorphisms may be responsible in part for genetic susceptibility to ITP. Genotyping of IFN-gamma +874A/T and IL-4 intron3 VNTR was performed in 196 patients with ITP and 128 healthy individuals by polymerase chain reaction sequence-specific primers and direct PCR respectively. There was no association between IFN-gamma +874A/T and IL-4 intron3 VNTR polymorphism and ITP risk when all patients, as a group, were analyzed. When the patients were subdivided into two groups: childhood ITP and adult ITP, no statistical differences were found in the genotype and allele frequencies of IFN-gamma +874A/T and IL-4 intron3 VNTR between the two groups and the controls. Similar results were observed between acute childhood ITP, chronic childhood ITP, acute adult ITP or chronic adult ITP and the controls. These polymorphisms were distributed similarly between the patients with ITP and the controls, demonstrating that these two candidate gene polymorphisms are not attributed to ITP susceptibility.

Efficacy of Helicobacter pylori eradication on platelet recovery in children with chronic idiopathic thrombocytopenic purpura

Aim: Little is known about the influence of environmental factors on the epidemiology of idiopathic thrombocytopenic purpura (ITP). The role of Helicobacter pylori infection in relation to the development and/or persistence of ITP in infected patients remains controversial. Therapy used for eradicating H. pylori has led to a rise in platelet counts in a significant number of adult patients, but few paediatric studies have been undertaken to evaluate such treatment. The aim of this prospective study was to determine the prevalence of H. pylori and to evaluate whether H. pylori eradication can induce chronic ITP regression in children. Methods: To investigate new, non‐invasive techniques for diagnosis of H. pylori infection, an enzyme immunoassay for H. pylori antigens in faeces (HpSA) was evaluated. Patient eligibility criteria included isolated thrombocytopenia (±50 ± 109 L−1) for more than 6 months without any identifiable cause and either normal or increased marrow megakaryocytes. H. pylori status was monitored before eradication and 4, 12, and 24 mo, after the end of treatment using Premier Platinum HpSA. Results: In this study we evaluated 22 chronic ITP patients, 9 of whom were infected with H. pylori. Using repeated HpSA testing, we demonstrated for eradication of H. pylori after treatment in all infected patients. Five of the nine patients had increased platelet counts that persisted throughout the follow‐up period. Conclusion: These results should stimulate additional research into the involvement of H. pylori infection in chronic ITP in childhood. This approach may offer an accepted algorithm at least for some of these patients.

Chronic childhood idiopathic thrombocytopenic purpura

Childhood idiopathic thrombocytopenic purpura (ITP) is a largely trivial disorder from which over 95% of children sooner or later recover spontaneously, and for most of whom the risks of unnecessary or ineffective therapy are arguably greater than those of the untreated disease. There are, however, a few patients who continue to have very low platelet counts and remain symptomatic for many months or years. They are rare, and they present difficult management problems. Splenectomy is probably the most effective treatment but is also the most dangerous and is not always successful. It is also irreversible. Most other regimens are either ineffective, unacceptably toxic, or both. Planning management for an individual patient requires a realistic risk:benefit appraisal, a process that is impeded by inadequate epidemiological data and a scarcity of large-scale randomized clinical trials. International collaborative studies may help in the future.

High-dose oral dexamethasone therapy for chronic childhood idiopathic thrombocytopenic purpura

Because high-dose oral dexamethasone therapy has been reported to be effective for adults with idiopathic thrombocytopenic purpura, we assessed the short-term efficacy and toxicity of dexamethasone in seven children with chronic or refractory idiopathic thrombocytopenic purpura. Dexamethasone therapy was effective and well tolerated; further long-term studies are warranted. (J P EDIATR 1996;128:281-3)

Seventeen years of experience with chronic idiopathic thrombocytopenic purpura in childhood. Is therapy always better?

Between 1975 and 1992 450 children with idiopathic thrombocytopenic purpura (ITP) were diagnosed, and of those 100 (22%) developed the chronic form of the disease. Approximately half the patients with chronic ITP presented with mild to moderate hemorrhagic manifestations at the onset of purpura (30 cases) and/or later during the course of the disease (25 cases). The incidence of intracranial hemorrhage was 1%, and the mortality rate due to overwhelming septicemia after splenectomy was also 1%. Overall one-third of the patients received no therapy; two-thirds of them went into spontaneous remission within 8 months to 8 years from the onset of ITP. Steroids given in conventional or high doses (51 cases) achieved a transient (if any) rise in platelet count, but in no case were steroids curative. Remission related to intravenous immune globulin (IVIG) therapy was noticed in 38.5% of the children (10 of 26) after variable courses. The response rate to splenectomy was 95.0%. Ultimately the long-term outcome in children with chronic ITP was as follows: remission, 58 cases (spontaneous, 30; after IVIG therapy, 10; after splenectomy, 18); hemostatic platelet values, 22 cases (spontaneous, 16; after IVIG, 5; after splenectomy, 1). Thirteen children were lost in follow-up, and 7 remain thrombocytopenic but asymptomatic. These data indicate that chronic ITP in childhood runs a benign course in most cases and may remit with or without therapy even several years from onset. Therefore, therapeutic intervention has to be individualized, and splenectomy, which is not always safe, should be reserved for problematic cases that fail to respond to conventional therapeutic modalities.

Childhood Idiopathic Thrombocytopenic Purpura: Experience at King Khalid University Hospital, Riyadh

Forty-nine children (30 boys and 19 girls) with idiopathic thrombocytopenic purpura (ITP) seen at King Khalid University Hospital (KKUH) Riyadh, during a 7-1/2 year period were retrospectively reviewed with regard to their clinical characteristics, management, and outcome. The age of onset of the disease ranged from 8 months to 11 years with a mean of 4.26 years. Twenty-seven cases presented as acute ITP while 22 cases presented as chronic ITP. The clinicopathological features and response to treatment of the cases were essentially similar to findings in other parts of the world. In a search for a predictor of chronic disease, the platelet counts at four weeks and three months after diagnosis were found to be a significant factor for prediction of chronicity of ITP. If the platelet counts are less than 100x10(9)/L during these periods, the risk of chronic ITP is increased and vice versa. There was, however, no correlation in our patients between duration of symptoms prior to presentation and outcome of the disease as has been reported by investigators in Europe and Australia.