Childhood immune thrombocytopenia: role of rituximab, recombinant thrombopoietin, and other new therapeutics

Investigation of the mechanism of action of Shengxuexiaoban Capsules against primary immune thrombocytopenia using network pharmacology and experimental validation

BACKGROUND

Shengxuexiaoban Capsules (SC) is a classical prescription in traditional Chinese medicine (TCM) and has been clinically adopted in the treatment of primary immune thrombocytopenia (ITP) in China. However, the underlying mechanisms of the actions of SC on ITP remain clear.

METHODS

A network pharmacology approach was adopted to investigate the underlying molecular mechanism of SC in treating ITP, and the effects of SC on the proliferation, differentiation, and apoptosis of megakaryocyte (MK) and on the ITP animal model were investigated.

RESULTS

Network pharmacology analysis found 128 active compounds and 268 targets of these compounds in SC, as well as 221 ITP-related targets. The topological analysis found a central network containing 82 genes, which were significantly associated with the regulation of transcription, cell proliferation, apoptosis processes, the PI3K-AKT signaling pathway, the MAPK signaling pathway, and the ERK1 and ERK2 cascades. It showed that SC increased the proliferation and differentiation of MK, but had no significant impact on MK apoptosis in vivo. The addition of SC increased the gene expression of several potential targets, including STAT3, KDR, CASP3, and TGFB1. In addition, SC administration elevated the protein expression of p-AKT and inhibit the protein expression of p-ERK, but has no impact on the protein expression of p-P38. Moreover, SC could improve haemogram parameters, coagulation indicators, and the proliferation and differentiation of MK in the ITP animal model.

CONCLUSIONS

The present study systematically elucidated the underlying mechanisms of SC against ITP and provided an efficient strategy to discover the pharmacological mechanism of TCM. It may strengthen the understanding of SC and facilitate more application of this formula in the treatment of ITP.

A novel immunomodulatory treatment involving mycophenolate mofetil and corticosteroids for pediatric autoimmune cytopenias

BACKGROUND

Successful treatment of both pediatric autoimmune hemolytic anemia (AIHA) and immune thrombocytopenic purpura (ITP), specifically those that are refractory to first-line therapies, remains unsatisfactory in terms of long-term remission and medication side effects. Here, we propose a novel combination therapy of mycophenolate mofetil (MMF), an adjunct immunosuppressive, and short-term corticosteroids for the treatment of persistent or chronic autoimmune cytopenias in children. This combination may allow for rapid decrease of steroid usage as well as prolonged count stabilization with minimal toxicity to the patient.

PROCEDURE

Prospective case series of nine patients, six with persistent or chronic ITP and three with persistent or chronic AIHA, between the ages of 5 and 19 years who are being treated with combination therapy consisting of corticosteroids and MMF.

RESULTS

All patients with ITP (Patients 4-9) and AIHA (Patients 1-3) met complete response (CR) criteria, as they all initially achieved platelet counts 100 × 10⁹ l^-1 or more or hemoglobin level greater than or equal to 10 g/dl, respectively, while on combination therapy and then maintained this level or higher while on MMF alone after steroids were discontinued.

CONCLUSIONS

Our results are very promising, as MMF appears to be an effective and well-tolerated adjunct immunosuppressant that allows for rapid weaning of steroid usage, minimal adverse side effects to the patients, and long-term stabilization of counts, a goal that has not been achieved successfully with other secondary treatment modalities. Therefore, this novel combination therapy may be an excellent alternative for the treatment of persistent or chronic autoimmune cytopenias in the pediatric population.

Clinical course and prognostic factors of childhood immune thrombocytopenia: single center experience of 10 years

Purpose

This study aimed to evaluate the clinical course of childhood immune thrombocytopenia (ITP) and to assess the risk factors for developing chronic ITP.

Methods

The records of 64 children diagnosed with ITP from November 2005 and December 2014 at single center were retrospectively analyzed.

Results

The median age at diagnosis and the median platelet count were 1 year (range, 1 month to 15 years) and 9×10⁹/L (range, 0–84×10⁹/L), respectively. No patient experienced severe bleeding. Nineteen children (29.7%) spontaneously recovered their platelet count to ≥100×10⁹/L at a median of 10 days. In total 45 patients (70.3%) received intravenous immunoglobulin (IVIG) as first-line therapy, and showed platelet recovery at 1 week. The final diagnosis of 55 (85.9%) and 9 patients (14.1%) was acute and chronic ITP, respectively. Older age, absence of prior infection and insidious onset of symptoms were significantly associated with the development of chronic ITP. Among the patients who received IVIG, those with platelet count <45×10⁹/L at 1 month after IVIG showed a significantly higher incidence of chronic ITP compared to those with platelet count ≥45×10⁹/L (88.8% vs. 44.4%, P<0.01).

Conclusion

In most patients, ITP runs a benign course and approximately 86% of them recover within 1 year of their initial diagnosis. The potential impact of the risk factors of chronic ITP on clinical practice needs to be explored and further studies are warranted to determine whether IVIG influences the course of ITP.

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.

Rituximab

Rituximab (Rituxan^®, MabThera^®, and Genentech/Roche) is a chimeric murine/human monoclonal IgG1k antibody directed against the CD20 antigen located at the surface of normal and malignant B lymphocytes.