Treatment of childhood chronic idiopathic thrombocytopenic purpura with ascorbate

Novel Biomarkers for Diagnosis and Monitoring of Immune Thrombocytopenia

Lower-than-normal platelet counts are a hallmark of the acquired autoimmune illness known as immune thrombocytopenia, which can affect both adults and children. Immune thrombocytopenia patients' care has evolved significantly in recent years, but the disease's diagnosis has not, and it is still only clinically achievable with the elimination of other causes of thrombocytopenia. The lack of a valid biomarker or gold-standard diagnostic test, despite ongoing efforts to find one, adds to the high rate of disease misdiagnosis. However, in recent years, several studies have helped to elucidate a number of features of the disease's etiology, highlighting how the platelet loss is not only caused by an increase in peripheral platelet destruction but also involves a number of humoral and cellular immune system effectors. This made it possible to identify the role of immune-activating substances such cytokines and chemokines, complement, non-coding genetic material, the microbiome, and gene mutations. Furthermore, platelet and megakaryocyte immaturity indices have been emphasized as new disease markers, and prognostic signs and responses to particular types of therapy have been suggested. Our review's goal was to compile information from the literature on novel immune thrombocytopenia biomarkers, markers that will help us improve the management of these patients.

Investigation of Dynamic Thiol/Disulfide Homeostasis in Children With Acute Immune Thrombocytopenia

Oxidative stress may play a role in the pathogenesis of immune thrombocytopenia (ITP), but the role of dynamic thiol/disulfide homeostasis has not been studied. The objective of this study was to assess whether there is a change in thiol/disulfide homeostasis in children with acute ITP. A total of 40 children with acute ITP and 50 healthy age-matched and sex-matched controls were included in this study. Serum total thiol and native thiol levels have been measured with a novel automatic spectrophotometric method. The amount of dynamic disulfide bonds and related ratios were calculated from these values. The average total thiol and native thiol levels of the patient group were found to be significantly lower than those levels of controls (P<0.01). However, intravenous immunoglobulin (IVIG) treatment with 1 g/kg/d prevented these reductions. disulfide level was slightly, but not significantly, depressed in ITP patients, but it recovered following IVIG treatment. We detected no marked changes in disulfide/total thiol, disulfide/native thiol, and native thiol/total thiol ratios between groups. These results are the first to demonstrate that thiol/disulfide homeostasis plays a role in ITP pathogenesis, and IVIG treatment can prevent the reduced thiol levels in children.

Medication Repurposing in Pediatric Patients: Teaching Old Drugs New Tricks

OBJECTIVES

Gaps in pediatric therapeutics often result in off-label use and specifically, novel uses for existing medications, termed "drug repurposing." Drug Information (DI) queries to a Pediatric Medication Resource Center of a large metropolitan pediatric hospital in New York and inherent difficulties in retrieving evidence-based information prompted a review of current medication repurposing for pediatric patients. The objective included characterization of innovative off-label use of medications Food and Drug Administration (FDA)-approved for 1 or more indications to treat a totally different disorder or indication in pediatric patients.

METHODS

A systematic literature review was conducted to retrieve publications describing repurposed medications in pediatric patients. Excluded was FDA-approved indications used off-label in pediatric patients (e.g., different dose), preclinical data, adult use only, and experimental use. Evidence quality was classified using a modified American Academy of Neurology Level of Evidence. Results were analyzed using χ(2) at p < 0.05.

RESULTS

Over 2000 references were retrieved and reviewed. A total of 101 medications repurposed for novel off-label uses for pediatric patients were identified: 38 for neonates, 74 for children, and 52 for adolescents. Neonates and infants were least likely to receive a medication for a repurposed use. Strong or intermediate evidence existed in 80.2% of cases. The evidence was weak in 19.8%. No significant relationship was observed between the pediatric age group and strength of the literature. Most repurposed uses pertained to generic or widely used medications. Less than 5% of medications were first marketed after 2011.

CONCLUSIONS

While not exhaustive, the present study represents the most comprehensive listing of novel uses exclusive to pediatric patients. Further research is needed to identify the frequency of repurposed uses. The valuable DI role of pharmacists in assessing repurposed uses is of expanding and increasing importance to ensure such uses are evidence-based.

Oxidative stress and immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by increased platelet destruction or decreased platelet production. The mechanism of the disease has been extensively studied so that we now have a much improved understanding of the pathophysiology; however, the trigger of the autoimmunity remains unclear. More recently, oxidative stress was identified to be involved in the pathogenesis of ITP and provides a new hypothesis for the initiation of autoimmunity in patients with ITP. In this review, oxidative stress and its impact on autoimmunity, particularly ITP, will be covered.

Management of immune thrombocytopenic purpura in children

Immune thrombocytopenic purpura (ITP) is the most common acquired bleeding disorder occurring in previously healthy children and can be classified into two major forms. Acute and chronic ITP are benign conditions with a high probability of spontaneous recovery with or without therapy. Rates of 80-90% complete remission can be achieved irrespective of the treatment given. In only 10-20% of children thrombocytopenia persists for more than six months, showing a chronic course, which also has a high probability of remitting over time (up to 80% or more). The variability of the clinical course, and the lack of consistent clinical features, make the decision on whether and how to treat difficult. Most physicians are driven to treat all children with symptoms by concern over life-threatening hemorrhage, although the risk of intracranial hemorrhage (ICH) is only 0.1-0.9%. The commonly used treatment regimens for acute ITP are corticosteroids, intravenous immunoglobulins (IVIgG), or intravenous anti-D immunoglobulin (anti-D). So far, there is no evidence that initial therapy can prevent ICH or a chronic course of the disease. In chronic ITP the same drugs are generally used and it seems that pulses with steroids may be just as effective as IVIgG. Anti-D may also be considered a reliable and cheap alternative for chronic disease. A major problem in the management of chronic ITP is the question of whether repeated infusions of Ig (IVIgG or anti-D) and/or corticosteroids can postpone or ultimately preclude splenectomy, which must be considered only for a small proportion of patients resistant to therapy. In these cases, a laparoscopic approach should be preferred. Children who fail to respond to splenectomy (< 20% of cases) warrant second line treatment with other drugs, like cyclophosphamide or azathioprine and deserve a revisit of diagnosis for exclusion of secondary ITP.

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.