Pathophysiology and management of primary immune thrombocytopenia

The Differences of Serum Thrombopoietin Levels Between Acquired Aplastic Anemia and Immune Thrombocytopenia in Pediatric Patients

Thrombopoietin (TPO) is the critical regulator of platelet production. However, the role of TPO in pediatric patients with thrombocytopenic disorders has not been fully elucidated. In the present study, we attempted to investigate serum TPO levels in patients with acquired aplastic anemia (aAA) and immune thrombocytopenia (ITP). We analyzed the endogenous plasma concentration of TPO and platelet count at the time of TPO measurement in 166 patients with aAA and 280 patients with ITP retrospectively. We further observed a correlation between platelet counts and TPO. Serum TPO levels were significantly higher in aAA compared with ITP (1142 vs. 77.99 pg/mL, P <0.001). In patients with aAA, an elevation for TPO levels in very severe AA (VSAA) was seen when compared with non-severe AA (NSAA) (1360 vs. 984.4 pg/mL, P <0.05). In contrast, the circulating TPO levels with chronic ITP (CITP) showed a decrease than newly diagnosed ITP (NITP) and persistent ITP (PITP) (62.28 vs. 81.56 pg/mL, P <0.01, 62.28 vs. 87.82 pg/mL, P <0.05, respectively). There was a negative correlation between platelet counts and TPO levels in aAA (r s =-0.3325, P <0.001) as well as ITP (r s =-0.2570, P <0.001). Especially, TPO levels were inversely correlated with platelet counts in NSAA (r s =-0.3672, P <0.001) and NITP (r s =-0.3316, P <0.001). After grouping by age or sex, there were no statistical differences in aAA or ITP. Serum TPO levels were markedly elevated in pediatric patients with aAA compared with ITP. It was higher in VSAA and lower in CITP, suggesting that serum TPO level could play a role in classifying disease severity or clinical course in aAA and ITP.

Treatment outcomes and adherence to treatment in patients with immune thrombocytopenia in two Ethiopian teaching hospitals: a retrospective cohort study

The treatment of immune thrombocytopenia (ITP) is challenging and treatment outcomes depend on numerous unknown and patient-specific factors. Corticosteroids are the cornerstone of ITP treatment, but they are associated with many side effects. In this retrospective cohort study, treatment outcomes and treatment adherence in patients with ITP were investigated in 214 ITP patients from November 15, 2022 to March 15, 2023. Multinomial regression analysis models were used to identify predictive factors for treatment outcomes. A p value of less than 0.05 was considered statistically significant. Most study participants were female 161 (75.5%), and the majority 172 (80.4%) of them were taking prednisolone only. In terms of treatment adherence, 178 (83.2%) of the study participants adhered well to their ITP medications. The complete response rate at 3 months was 139 (65.0%). Predictive factors for partial response were increased negative impact of ITP on health-related quality of life (AOR = 1.221, 95% CI 1.096-1.360), being treated at Tikur Abessa Sepcialazed Hospital (AOR = 0.431, 95% CI 0.197-0.941) and the presence of heavy menstrual bleeding (AOR = 2.255, 95% CI 0.925-5.497) compared to patients with complete response. Hepatitis B virus-infected ITP patients (AOR = 0.052, 95% CI 0.004-0.621) were also a predictive factor for no response compared to complete response.

Risk of fractures and use of bisphosphonates in adult patients with immune thrombocytopenia-A nationwide population-based study

Corticosteroids remain the first-line treatment of immune thrombocytopenia (ITP), but increase the risk of osteoporosis and fractures. Bisphosphonates are used for the treatment of osteoporosis, but their usage among patients with ITP has not been systemically described. We investigated the risk of fractures and the use of bisphosphonates in adult patients with primary (pITP) and secondary ITP (sITP) compared with matched comparators in a nationwide registry-based cohort study. We identified 4030 patients with pITP (median age 60 years [IQR, 40-74]), 550 with sITP (median age 59 years [IQR, 43-74]) and 182 939 age-sex-matched general population comparators. All individuals were followed for incident fractures. Bisphosphonate use was estimated for calendar-years and in temporal relation to the ITP diagnosis. Adjusted cause-specific hazard ratio (csHR) for any fracture was 1.37 (95% confidence interval [CI] 1.23; 1.54) for pITP and 1.54 (1.17; 2.03) for sITP. The first-year csHR was 1.82 (1.39; 2.40) for pITP and 2.78 (1.58; 4.91) for sITP. Bisphosphonate use over calendar-years and in the early years following ITP diagnosis was higher among patients with ITP diagnosis compared with the general population. In conclusion, the risk of fractures and the use of bisphosphonates are higher in patients with ITP compared with the general population.

Autoimmune diseases: targets, biology, and drug discovery

Autoimmune diseases (AIDs) arise from a breakdown in immunological self-tolerance, wherein the adaptive immune system mistakenly attacks healthy cells, tissues and organs. AIDs impose excessive treatment costs and currently rely on non-specific and universal immunosuppression, which only offer symptomatic relief without addressing the underlying causes. AIDs are driven by autoantigens, targeting the autoantigens holds great promise in transforming the treatment of these diseases. To achieve this goal, a comprehensive understanding of the pathogenic mechanisms underlying different AIDs and the identification of specific autoantigens are critical. In this review, we categorize AIDs based on their underlying causes and compile information on autoantigens implicated in each disease, providing a roadmap for the development of novel immunotherapy regimens. We will focus on type 1 diabetes (T1D), which is an autoimmune disease characterized by irreversible destruction of insulin-producing β cells in the Langerhans islets of the pancreas. We will discuss insulin as possible autoantigen of T1D and its role in T1D pathogenesis. Finally, we will review current treatments of TID and propose a potentially effective immunotherapy targeting autoantigens.

Challenges in Treating Extensive Deep Vein Thrombosis with Severe Thrombocytopenia in Patients with Antiphospholipid Syndrome-A Follow-up of 2 Years

Thrombocytopenia is one of the most common manifestations of antiphospholipid syndrome (APS). There is little evidence or definitive guidelines regarding the treatment of APS with thrombocytopenia. We describe a patient with APS and moderate-to-severe thrombocytopenia and the challenges of balancing anticoagulation with thrombocytopenia. A 19-year-old male patient presented with right lower limb swelling to the emergency department with a history of gradually worsening right leg swelling for 1 week and was diagnosed with right leg proximal deep vein thrombosis. Ultrasound Doppler of the right lower limb revealed complete venous thrombosis from the level of the popliteal vein to the distal superficial femoral vein. Subsequently, he was found to have triple-positive APS and moderate-to-severe immune thrombocytopenia, with a platelet count nadir of 31 × 10 to the ninth power/L. He was started on anticoagulation with warfarin. The severe thrombocytopenia was not treated with immunosuppressants and the platelets fluctuated in the range of moderate-to-severe thrombocytopenia but did not develop any rethrombotic or bleeding events. His platelets varied from 31 × 10 to the ninth power/L to 106 × 10 to the ninth power/L. This case report demonstrates that it may be safe to hold off treatment for thrombocytopenia in APS, even in cases of severe thrombocytopenia. Treatment with immunosuppressants may be instituted only when platelet levels fall below 20 × 10 to the ninth power/L or when there is clinically significant bleeding, as in primary immune thrombocytopenia.

Reference guide for the diagnosis of adult primary immune thrombocytopenia, 2023 edition

Primary immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia due to accelerated platelet destruction and impaired platelet production. Diagnosis of ITP is still challenging because ITP has been diagnosed by exclusion. Exclusion of thrombocytopenia due to bone marrow failure is especially important in Japan because of high prevalence of aplastic anemia compared to Western countries. Hence, we propose a new diagnostic criteria involving the measurement of plasma thrombopoietin (TPO) levels and percentage of immature platelet fraction (RP% or IPF%); 1) isolated thrombocytopenia with no morphological evidence of dysplasia in any blood cell type in a blood smear, 2) normal or slightly increased plasma TPO level (< cutoff), 3) elevated RP% or IPF% (> upper limit of normal), and 4) absence of other conditions that potentially cause thrombocytopenia including secondary ITP. A diagnosis of ITP is made if conditions 1-4 are all met. Cases in which criterion 2 or 3 is not met or unavailable are defined as "possible ITP," and diagnosis of ITP can be made mainly by typical clinical course. These new criteria enable us to clearly differentiate ITP from aplastic anemia and other forms of hypoplastic thrombocytopenia and can be highly useful in clinical practice for avoiding unnecessary bone marrow examination as well as for appropriate selection of treatments.

Rapid, Simple and Low-Cost Analytical Method Development for Quantification of Eltrombopag Olamine in Tablet Dosage by UV Spectroscopy Method

BACKGROUND

Eltrombopag Olamine is a drug used to treat thrombocytopenia, a disorder where blood platelet counts get lower and severe aplastic anemia. It serves as a thrombopoietin receptor agonist, which give rise to platelet production in the bone marrow.

OBJECTIVES

The objective of this study is to develop a simple, specific, accurate, precise and economical Ultraviolet spectroscopy method to estimate the amount of Eltrombopag Olamine in bulk and tablet dosage form.

METHODS

The developed method was performed using methanol for identification and physicochemical characterization of the drug. The validation parameters like linearity, precision, accuracy, robustness limits of detection and quantitation, and specificity were assessed as per ICH Q2 (R2).

RESULTS

The maximum absorbance wavelength (λmax) of the drug was found at 247 nm in methanol. The linearity was found in the concentration range of 2-14 μg/ml with regression equation y = 0.0619x - 0.0123 and r² = 0.999. The standard addition method was used to determine the accuracy of the developed method. The result was found in the % recovery range of 98-99%. The precision was done on λmax with respect to the parameters such as repeatability, intraday, and interday. The method was found to be precise as the % RSD value was found to be <2%. The detection limit value (LOD) and quantitation limit value (LOQ) were 0.0524 μg/ml and 0.1588 μg/ml, respectively.

CONCLUSION

The developed method is simple, economical, accurate and selective. The developed method was adaptable for the estimation of Eltrombopag Olamine analysis in pharmaceutical dosage form and routine quality control laboratory.

Maternal Coagulation Disorders and Postpartum Hemorrhage

Coagulation disorders are rare causes of postpartum hemorrhage. Disturbances in coagulation should be suspected in patients with a family history of coagulopathy, those with a personal history of heavy menstrual bleeding, and those with persistent bleeding despite correction of other causes. The coagulopathic conditions discussed include disseminated intravascular coagulation, platelet disorders, and disturbances of coagulation factors. These should not be overlooked in the evaluation of obstetric hemorrhage, as diagnosis and appropriate treatment may prevent severe maternal morbidity and mortality.

Survival in adult patients with chronic primary and secondary immune thrombocytopenia: A population-based study

BACKGROUND

Few studies have investigated long-term survival in patients with primary immune thrombocytopenia (pITP). Further, changes in prognosis over the past decades and prognosis of secondary immune thrombocytopenia (sITP) are largely unstudied. Our objectives were to study comorbidity-adjusted prognostic changes and causes of death in chronic pITP and sITP patients.

STUDY DESIGN/METHODS

Using nationwide Danish health registries 1980-2016, we identified 1762 patients with chronic pITP (median age 58 (IQR, 37-73) years) and 128 with chronic sITP (median age 59 (IQR, 40-73) years). Patients were age-sex-matched to 74,781 general population comparators. Comorbidity was assessed using Charlson Comorbidity Index (CCI).

RESULTS

Overall median survival was reduced by 5.1 years (95% CI, 0.7-9.4) (p < .001) for pITP and 11.1 years (95% CI, 5.8-16.4) (p < .001) for sITP. 5-year survival increased from 69% (95% CI, 59-78) in 1980-89 to 80% (95% CI, 75-83) in 2010-16 for pITP, and decreased from 100% (95% CI, 89-98) to 64% (95% CI, 87-91) for sITP. However, numbers were small for sITP. 5-year survival for pITP with high CCI was 41% (95% CI, 32-49), and 85% (95% CI, 83-87) for low CCI. Bleeding, infection and hematological cancer were relatively frequent causes of death with adjusted subhazard ratios of 3.25 (95% CI, 2.33-4.52), 1.53 (95% CI, 1.08-2.16) and 2.16 (95% CI, 1.12-4.16) in pITP respectively, and 10.52 (95% CI, 1.43-77.36) for hematological cancer in sITP.

CONCLUSIONS

Long-term survival is reduced in chronic ITP but seems to be improving. Comorbidity and sITP are associated with a poor prognosis.

Resolved Hypereosinophilic Syndrome and Immune Thrombocytopenic Purpura in Ulcerative Colitis Patients Post Colectomy: A Case Series and Literature Review

Introduction

Hypereosinophilic syndrome (HES) and immune thrombocytopenic purpura (ITP) have been reported to co-occur with ulcerative colitis (UC). However, the exact pathogenic mechanisms of their occurrence remain elusive. In this article, we aim to describe two cases of UC patients who developed refractory HES and ITP and elaborate on their potential pathogenesis.

Case Study

We report two middle-aged patients diagnosed with UC. The first patient developed HES that was refractory to conventional medical therapy of idiopathic HES, and the second developed refractory ITP that failed steroid and immunosuppressive therapy. Both conditions improved considerably following colectomy, suggesting they are of a reactive rather than idiopathic nature.

Conclusion

In patients with UC and refractory comorbid HES or ITP, the reactive nature of these comorbidities should be taken into consideration, and colectomy, therefore, should be considered if clinically indicated.

Downregulation of ADAM17 in pediatric immune thrombocytopenia impairs proplatelet formation

BACKGROUND

Immune thrombocytopenia (ITP) is the most common etiology of acquired thrombocytopenia diseases in children. ITP is characterized by the immune-mediated decreased formation and excessive destruction of platelets. The pathogenesis and management of pediatric ITP are distinct from adult ITP. A disintegrin and metalloproteinase 17 (ADAM17) mediates the shedding of platelet receptor glycoprotein Ib α (GPIb α) in extracellular domain, functioning in the platelet activation and clearance. Our study aims to probe the roles and mechanisms of ADAM17 in pediatric ITP.

METHODS

The differently expressed ADAM17 in megakaryocytes was obtained from children with ITP through the next-generation RNA-Sequence. Hematoxylin-eosin and Giemsa staining were performed for cell morphology identification. Flow cytometry was applied to assess autoantibodies against platelets, subtypes of lymphocytes, the surface expression level of ADAM17 and polyploidization of megakaryocytes, as well as the full-length GP Ib α.

RESULTS

ADAM17 was significantly downregulated in megakaryocytes and platelets in children with ITP. Higher values of PDW and positive autoantibodies presence were observed in children with ITP. Loss of ADAM17 in mice led to defects in proplatelet formation and significantly elevated expression of phosphorylated myosin light chain (p-MLC) in megakaryocytes.

CONCLUSIONS

Our study indicated that the downregulation of ADAM17 might be an innate cause of inefficient platelet production in pediatric ITP.

Stromal Derived Factor-1 Gene Polymorphism in Pediatric Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a multifactorial disease in which both environmental and genetic factors have been implicated. The study aimed to investigate a possible association of single nucleotide polymorphisms (SNPs rs266085 and rs2839693) in the stromal derived factor-1 (SDF-1) gene and its association to ITP and effect on ITP severity and response to treatment. Genomic DNA was extracted from peripheral blood and polymorphism in SDF-1 gene rs266085 and rs2839693 was analyzed using PCR-restriction fragment length polymorphism technique in DNA extracted from 60 children with ITP together with 90 healthy controls. On analysis of SDF-1 rs266085 polymorphism, there was a high frequency of CC genotype in cases than controls and that difference was significant at codominant, overdominant, and dominant models (P<0.05). Furthermore, carriers of the CC genotype were more susceptible to severe ITP at onset, steroid dependency, and chronicity than carriers of other genotypes (P<0.05). Otherwise, no significant differences between ITP patients and controls as regard SDF-1 rs2839693 genotypes and alleles, and we did not find a relation between this polymorphism and ITP severity, steroid dependency, or duration. SDF-1 gene rs266085 SNP C allele is associated with susceptibility to develop ITP as well as increases the risk for severe ITP at onset, chronic ITP and steroid dependency.

Development of an Automated Chemiluminescent Enzyme Immunoassay for Measuring Thrombopoietin in Human Plasma

Plasma thrombopoietin (TPO) measurements help distinguish between different types of thrombocytopenia but are not feasible in routine clinical practice. We developed a fully automated quantitative chemiluminescent enzyme immunoassay (CLEIA) for measuring TPO (TPO-CLEIA), which is a one-step sandwich-type assay. This assay utilizes a mouse monoclonal capture antibody, which has the neutralizing epitope of the interaction between TPO and the TPO receptor, and a newly generated rabbit monoclonal detector antibody. In analytical performance studies, this assay showed good linearity over the measuring range and high sensitivity. The limit of quantification (LoQ) of this assay was 3.4 pg/mL; low TPO concentration values of almost all healthy individuals exceeded the LoQ value. In clinical validation studies, TPO levels obtained from patients with aplastic anemia (AA) significantly increased, whereas those of patients with immune thrombocytopenia (ITP) were normal or slightly increased. The cutoff value for TPO-CLEIA corresponding to the previously reported values was useful for distinguishing between ITP and AA. These results suggest that TPO-CLEIA can quantify human plasma TPO levels with high accuracy and sensitivity and has the potential to facilitate routine clinical measurement of TPO in patients with various types of thrombocytopenia.

Autoimmune-mediated thrombocytopenia after allogeneic hematopoietic stem cell transplantation: significance of detecting reticulated platelets and glycoprotein-specific platelet autoantibodies

Autoimmune hematological disorders are rare complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Diagnosis of immune thrombocytopenia (ITP) is challenging, especially after allo-HSCT, because various complications such as graft-versus-host disease, disease relapse, viral infection, thrombotic microangiopathy, and drug side effects can also cause thrombocytopenia. Assessment of reticulated platelets (RP) and plasma thrombopoietin (TPO) levels may be useful to distinguish between ITP and hypoplastic thrombocytopenia. ITP is generally characterized by an increased percentage of RP, and a normal or slightly increased plasma TPO level. We now report three cases of thrombocytopenia after allo-HSCT. RP% was elevated in these patients, as it is in primary ITP. However, in contrast to primary ITP, plasma TPO levels were high in two of three patients. Anti-αIIbβ3 and anti-GPIb/IX-specific direct IgG antibodies were detected as well, suggesting occurrence of immune-mediated platelet destruction in addition to bone marrow suppression in two patients. All three patients were successfully treated with corticosteroids and/or thrombopoietin receptor agonists (TPO-RAs). These results suggest that increased RP% and detection of glycoprotein-specific platelet autoantibodies are useful for the diagnosis of ITP after HSCT.

IgG regulation through FcRn blocking: A novel mechanism for the treatment of myasthenia gravis

The neonatal Fc receptor (FcRn) is an MHC class I-like molecule that is widely distributed in mammalian organs, tissues, and cells. FcRn is critical to maintaining immunoglobulin G (IgG) and albumin levels through rescuing these molecules from lysosomal degradation. IgG autoantibodies are associated with many autoimmune diseases, including myasthenia gravis (MG), a rare neuromuscular autoimmune disease that causes debilitating and, in its generalized form (gMG), potentially life-threatening muscle weakness. IgG autoantibodies are directly pathogenic in MG and target neuromuscular junction proteins, causing neuromuscular transmission failure. Treatment approaches that reduce autoantibody levels, such as therapeutic plasma exchange and intravenous immunoglobulin, have been shown to be effective for gMG patients but are not indicated as ongoing maintenance therapies and can be associated with burdensome side effects. Agents that block FcRn-mediated recycling of IgG represent a rational and promising approach for the treatment of gMG. Blocking FcRn allows targeted reduction of all IgG subtypes without decreasing concentrations of other Ig isotypes; therefore, FcRn blocking could be a safe and effective treatment strategy for a broad population of gMG patients. Several FcRn-blocking antibodies and one antibody Fc fragment have been developed and are currently in various stages of clinical development. This article describes the mechanism of FcRn blockade as a novel approach for IgG-mediated disease therapy and reviews promising clinical data using such FcRn blockers for the treatment of gMG.

Favorable prognosis of vaccine-associated immune thrombocytopenia in children is correlated with young age at vaccination: Retrospective survey of a nationwide disease registry

Childhood vaccine-associated immune thrombocytopenia (ITP) has a mostly favorable prognosis. To identify factors associated with prognosis, a retrospective survey was conducted with children with ITP who were registered in the Japanese Society of Pediatric Hematology/Oncology registry from 2008 to 2011. A total of 477 patients were categorized into four groups by event preceding ITP onset: vaccine-precedence (VP; n = 43), vaccine/infection-precedence (VIP; n = 34), infection-precedence (IP; n = 162), and no vaccine/infection-precedence (NVI; n = 238). Compared to IP and NVI, VP and VIP were significantly younger at diagnosis, with the age distribution peaking at infancy, and more frequently had favorable prognosis. Time to platelet recovery to 100 × 10³/µL was significantly faster for VP and VIP than NVI. Multivariate Cox regression analysis with sex, age at diagnosis, infection-precedence, and vaccine-precedence as variables revealed age < 36 months (HR 0.992, 95% CI 0.989-0.995; p < 0.001) and male sex (HR 0.770, 95% CI 0.623-0.952; p = 0.015) as associated factors, but not infection-precedence (p = 0.149) or vaccine-precedence (p = 0.650). In subgroup analysis in patients < 36 months, age at diagnosis (p < 0.001) was the only associated factor. Favorable prognosis of childhood vaccine-associated ITP is correlated with young age at vaccination, but not with vaccination itself.

Comparative study of IgG binding to megakaryocytes in immune and myelodysplastic thrombocytopenic patients

Immune thrombocytopenia (ITP) is a disorder in which autoantibodies are responsible for destruction and decreased production of platelets. In the meantime, thrombocytopenia is frequent in patients with myelodysplastic syndromes (MDS) and immune clearance of megakaryocytes could be a reason. The aim of the present study is to evaluate and compare IgG binding to megakaryocytes in bone marrow of ITP and MDS patients to determine megakaryocytes targeting by autoantibodies in vivo as a mechanism of platelet underproduction in these disorders. The study was carried out on 20 ITP (group I) patients, 20 thrombocytopenic patients with (MDS) (group II), and 20 non-ITP patients as a control (group III) who were admitted to Minia University Hospital. Serial histological sections from bone marrow biopsies were stained for IgG. All patients in group I and 50% of group II patients showed bleeding tendency and the difference was significant (p < 0.001). No patient experienced fatigue in group I while 35% of patients in group II complained of easy fatigability, and the difference was significant (p < 0.008). High IgG antibody binding was found in ITP and MDS compared to the control group but no significant difference between ITP and MDS patients (14/20 (70%) vs. 13/20 (65%)) (p value = 0.736). Antibody binding to megakaryocytes in a proportion of MDS patients suggests that immune-mediated mechanism underlies platelet underproduction in those patients.

Fostamatinib: A Review in Chronic Immune Thrombocytopenia

Fostamatinib (Tavalisse^®; Tavlesse^®) is the first spleen tyrosine kinase (Syk) inhibitor approved for the treatment of chronic immune thrombocytopenia (ITP) in adult patients who have had an insufficient response to previous treatment. By inhibiting Syk activation in macrophages, fostamatinib blocks autoantibody-mediated platelet phagocytosis. In the placebo-controlled phase III FIT1 and FIT2 trials, 24 weeks of oral fostamatinib therapy increased platelet count in previously treated adults with ITP. A significantly higher proportion of patients achieved stable response with fostamatinib than with placebo in FIT1, but not in FIT2; however, pooled analyses of the two studies showed that fostamatinib produced significantly higher stable and overall response rates than placebo. Interim findings from the ongoing FIT3 open-label extension study suggested that the efficacy of fostamatinib was maintained with long-term treatment (up to 62 months; median duration 6 months), including in patients receiving fostamatinib as second- or later-line treatment. Fostamatinib had a generally manageable tolerability profile in all three FIT studies, with no serious safety risks. Fostamatinib therefore provides an alternative treatment option for chronic ITP in adult patients with an insufficient response to previous treatment.

Management of primary immune thrombocytopenia in a real-world setting in Japan: eltrombopag versus corticosteroids

This real-world study in Japan assessed the long-term safety of persistent use of eltrombopag compared to corticosteroids. Overall, 1887 patients with primary immune thrombocytopenia were included in the study cohort, based on hospital claims data. Eltrombopag was frequently used as a second- or third-line therapy (monotherapy: 13.1% and 25.7%; combination: 24.39% and 16.52%, respectively). The risk of bleeding was approximately 30% lower in the eltrombopag group (as monotherapy and in combination with other drugs including corticosteroids) than the corticosteroid group (hazard ratio, 0.66; 95% confidence interval, 0.45-0.96). Results from univariate and multivariate Cox models indicated that patients aged ≥ 60 years, male patients and patients who received the drugs for peptic ulcer or gastroesophageal reflux disease have a higher risk of cerebral haemorrhage or gastrointestinal bleeding. Surgeries were more common among patients on corticosteroids compared to patients on eltrombopag (39.1% vs 34.6%, P = 0.004), while splenectomies were very rare. There was no significant difference in the costs of scheduled, emergency, or any type of hospitalisations between the exposure groups. The risk of infections, cataracts, and thrombosis did not differ between the exposure groups.

Primary Immune Thrombocytopenia: Novel Insights into Pathophysiology and Disease Management

Immune thrombocytopenia (ITP) is an autoimmune disorder defined by a significantly reduced number of platelets in blood circulation. Due to low levels of platelets, ITP is associated with frequent bruising and bleeding. Current evidence suggests that low platelet counts in ITP are the result of multiple factors, including impaired thrombopoiesis and variations in immune response leading to platelet destruction during pathological conditions. Patient outcomes as well as clinic presentation of the disease have largely been shown to be case-specific, hinting towards ITP rather being a group of clinical conditions sharing common symptoms. The most frequent characteristics include dysfunction in primary haemostasis and loss of immune tolerance towards platelet as well as megakaryocyte antigens. This heterogeneity in patient population and characteristics make it challenging for the clinicians to choose appropriate therapeutic regimen. Therefore, it is vital to understand the pathomechanisms behind the disease and to consider various factors including patient age, platelet count levels, co-morbidities and patient preferences before initiating therapy. This review summarizes recent developments in the pathophysiology of ITP and provides a comprehensive overview of current therapeutic strategies as well as potential future drugs for the management of ITP.

The role and mechanism of miR-557 in inhibiting the differentiation and maturation of megakaryocytes in immune thrombocytopenia

Specific miRNA in immune thrombocytopenia (ITP) was screened to explore its intervention effects and mechanisms in ITP. MTT assay and CFSE staining were used to detect the effects of gradient concentrations of thrombopoietin (TPO) on cell proliferation. Expressions of differentially expressed miRNAs were analysed via qRT-PCR in TPO-induced megakaryocytes and ITP plasma. Effects of miR-557 on cell physiological functions were examined by MTT and flow cytometry. Expressions of miR-557, apoptosis-associated genes and Akt/ERK pathways were detected by qRT-PCR and Western blot as needed. Multinucleation of TPO-induced megakaryocytes was determined by megakaryocyte colonies. The toe skin and intestinal bleeding of the ITP rat model were observed and evaluated. Effects of miR-557 on the numbers of platelets, megakaryocytes, and peripheral blood platelets and the expressions of CD4⁺ T cells, Treg cells, TGF-β, IL-6 and miR-557 in the ITP rats were detected by Giemsa staining, flow cytometry, ELISA and qRT-PCR. MiR-557 was identified as an specific miRNA associated with both ITP and TPO treatment. MiR-557 inhibitor enhanced the physiological functions of TPO-induced megakaryocytes, while miR-557 mimic had the opposite effect. At the molecular level, the expressions of miR-557, cleaved Caspase-3 and Bax were further silenced by inhibitor, on the contrary, the expressions of bcl-2, p-Akt and p-ERK were upregulated. Animal experiments showed that, miR-557 inhibitor increased the numbers of platelets and megakaryocytes, and improved the symptoms of ITP model rats. Our results indicated that miR-557 inhibitor improved ITP by regulating apoptosis-related genes and cellular immunity and activating the Akt/ERK pathway.

Association between Platelet-Associated Immunoglobulin G Levels and Response to Corticosteroid Therapy in Patients with Newly Diagnosed Immune Thrombocytopenia

OBJECTIVE

Platelet-associated immunoglobulin G (PA-IgG) refers to IgG attached to the surface of platelets, while the immature platelet fraction (IPF) reflects the state of platelet production in bone marrow. Since PA-IgG and IPF are increased in patients with immune thrombocytopenia (ITP), reflecting amounts of platelet antibodies and compensatory platelet production, respectively, we hypothesized that these laboratory findings may provide useful markers for predicting treatment response in patients with ITP. We therefore retrospectively investigated associations between levels of these markers at diagnosis and response to first-line therapy in patients with ITP.

METHODS

Forty-three patients diagnosed with ITP at Oita Kouseiren Tsurumi Hospital between May 2010 and November 2018 were included. Patients were divided into 2 groups based on response to corticosteroid as first-line therapy. Laboratory findings were compared between responders and nonresponders.

RESULTS

Median PA-IgG was 285 ng/107 cells (range, 45.5-18,200 ng/107 cells), and median IPF was 15.5% (range, 5.4-62.1%). Median levels were higher than the respective upper limits of normal range (PA-IgG, 0-46 ng/107 cells; IPF, 1.1-9.5%). First-line therapy was performed using standard-dose prednisolone (0.5-1.0 mg/kg/day) in 32 patients and high-dose dexamethasone (40 mg/day, 4 days) or methylprednisolone (125-1,000 mg/day, 3-4 days) in 11 patients. Twenty-four patients (55.8%) responded to first-line therapy. In univariate analysis, type of corticosteroid (p = 0.17) tended to differ between groups but did not differ significantly, and no difference in IPF level was apparent between responders (15.35%; range, 5.4-41.5%) and nonresponders (16.7%; range, 6.3-62.1%; p = 0.15). PA-IgG was significantly higher among nonresponders (430 ng/107 cells; range, 101-18,200 ng/107 cells) than among responders (254.5 ng/107 cells; range, 45.5-470 ng/107 cells; p = 0.004). Multivariate analysis revealed PA-IgG was independently associated with response to first-line therapy (odds ratio, 1.000; 95% confidence interval, 1.000-1.010; p = 0.029).

CONCLUSION

Our data suggested that PA-IgG at diagnosis could offer a useful predictor of response to first-line corticosteroid therapy for ITP.

Lenalidomide-Associated Immune Thrombocytopenia: A Case Report and Review of the Literature

Lenalidomide is indicated in the front-line management of multiple myeloma. More recently, it has been introduced for use in treating other hematologic malignancies. Although the drug is known to cause myelosuppression, there have been rare reports of lenalidomide-associated immune thrombocytopenia (ITP). Here, we review the literature on lenalidomide-associated ITP and report upon a 59-year-old man who was administered lenalidomide due to concern of progressive multiple myeloma more than a year following his having undergone an autologous hematopoietic stem cell transplant. His platelet count precipitously declined and lead to his hospitalization. Despite our withholding of the drug, he did not respond to platelet transfusions or administration of corticosteroids. He was successfully managed with intermittent immune globulin for several months before definitive treatment with splenectomy, which resulted in the complete resolution of his thrombocytopenia. A literature search identified a total of six additional cases of lenalidomide-associated ITP. Similarly, many of the reported cases were associated with persistent thrombocytopenia after discontinuation of the drug. Furthermore, these patients were generally managed successfully with standard ITP therapies, such as corticosteroids or intravenous immune globulin.

Autologous platelet scintigraphy and clinical outcome of splenectomy in immune thrombocytopenia: A systematic review and meta-analysis

Autologous platelet sequestration pattern is associated with post-splenectomy platelet response in patients with immune thrombocytopenia (ITP). However, published results are contradictory, and have not been systematically reviewed. Our aim is to systematically review and meta-analyse the association between sequestration pattern and post-splenectomy platelet response. Articles were selected from MEDLINE when they a) included ITP patients, b) performed scintigraphy, and c) included post-splenectomy platelet response. The 23 included studies (published between 1969-2018) represented 2966 ITP-patients. Response to splenectomy occurred most frequently in patients with a splenic pattern (87.1 % in splenic versus 47.1 % in mixed and 25.5 % in hepatic patterns). A pooled analysis of 8 studies showed an odds ratio of 14.21 (95 % CI: 3.65-55.37) for platelet response in the splenic versus the hepatic group. Our findings indicate that a splenic sequestration pattern is associated with better response after splenectomy. Platelet sequestration patterns may be useful in the clinical decision-making regarding splenectomy.

Visualization of autoantibodies and neutrophils in vivo identifies novel checkpoints in autoantibody-induced tissue injury

In several autoimmune diseases, e.g., pemphigoid disease (PD), autoantibodies are the direct cause of pathology. Albeit key requirements for antibody-mediated diseases were identified, their interactions and exact temporal and spatial interactions remained elusive. The skin is easily accessible for imaging. Thus, we selected epidermolysis bullosa acquisita (EBA), a PD with autoantibodies to type VII collagen (COL7), to visualize interactions of autoantibodies, target tissue and effector cells (neutrophils). Following injection into mice, anti-COL7 IgG bound to the dermal-epidermal junction (DEJ) within minutes. We unexpectedly observed an inhomogeneous distribution of autoantibodies along the DEJ. Thus, we hypothesized that specific external triggers may affect autoantibody distribution. Indeed, mechanical irritation led to an increased autoantibody binding along the DEJ. Subsequently, anti-COL7 IgG was injected into mice expressing green fluorescent protein under the LysM promoter (LysM-eGFP) mice. This allows to visualize myeloid cells in vivo in these animals. Using multiphoton imaging, we observed a limited extravasation of LysM-eGFP⁺ cells into skin was observed within 24 hours. Intriguingly, LysM-eGFP⁺ cells did not immediately co-localize with autoantibodies, which was only noted at later time points. Of note, interactions of LysM-eGFP⁺ with the autoantibodies at the DEJ were short-lived. Collectively, our results define the following checkpoints for autoantibody-induced tissue injury: (i) autoantibody egress to target tissue influenced by mechanical trigger factors, (ii) neutrophil recruitment into the vicinity of autoantibody deposits and (iii) short-term neutrophil localization to these deposits, as well as (iv) delayed recruitment of neutrophils with subsequent autoantibody-induced inflammation.

Clinical effect and safety evaluation of different dosage of Rituximab combined with Cyclophosphamide in treatment of refractory immune Thrombocytopenia

Objective:

To discuss clinical effect of different dosage of rituximab combined with cyclophosphamide in treatment of refractory immune thrombocytopenia (rITP).

Method:

This study was conducted at Department of Hematopathology in XX Hospital from January 2016 to January 2018. In this study. Seventy-eight patients with rITP were selected as the objects, divided into observation group (39 cases) and control group (39 cases) according to random number table. Patients in the control group were treated with conventional rituximab and cyclophosphamide, while the observation group received low-dose rituximab. The same amount of cyclophosphamide was used in the two groups. The statistics of clinical effect, recurrence rate, untoward effect and Laboratory inspection of both groups were made before and after the treatment.

Results:

Compared with the control group, the total occurrence rate of side effects in the observation group decreased significantly; the level of IgM and CD20⁺ in the observation group also decreased significantly, while. The level of IgA, IgG, CD3+ and CD4+ rose significantly (P<0.05). The differences in the level of Th1, TNF-a, IL-18 and Sc5b-9 had statistical significance before and after the treatment (P<0.05).

Conclusion:

Rituximab combined with cyclophosphamide has the definite curative effect on rITP. The small dosage of rituximab combined with cyclophosphamide has higher clinical safety in the treatment.

Proposal of treatment algorithm for immune thromocytopenia in adult patients of a hematology service at a referral center in Northeastern Brazil

Introduction

The management of adult (≥18 years) immune thrombocytopenia patients relies on platelet count, the risk of bleeding and presence of bleeding.

Objective

Confirming the diagnosis of immune thrombocytopenia and the start of therapy, our hematology service, a referral center, favors the establishment of this algorithm to treat those patients.

Results

Presentation, recently diagnosed or recurrence – group 1: life-threatening bleeding: high-dose intravenous immunoglobulins with methylprednisolone or dexamethasone. Hospitalization and platelet transfusion are considered. Group 2: Platelets <30 × 10⁹/L with bleeding or risk factor for bleeding, or platelets <20 × 10⁹/L: prednisone or dexamethasone. No response, platelets <20 × 10⁹/L: replace corticoid or increase doses. If platelets continue <20 × 10⁹/L: immunization and splenectomy. Investigation of Helicobacter pylori, if positive: treatment for H. pylori. Chronic immune thrombocytopenia with platelets <20 × 10⁹/L we propose two new groups (A and B): Group A: <65 years, no or low surgical risk, patient declines maintenance therapy or patient intends to get pregnant: immunization and splenectomy. Group B: failure of splenectomy (refractory) or no splenectomy indication or history of exposure to malaria or babesiosis and no response to corticoids or corticoid dependence: choose thrombopoietin receptor agonists: eltrombopag or romiplostim. Patient at high risk for arterial or venous thrombosis: recommend rituximab. After rituximab or thrombopoietin receptor agonists, if platelets continue <20 × 10⁹/L: indicate immunosuppressants (azathioprine or cyclophosphamide), dapsone or mycophenolate mofetil or vinca alkaloids. The goals of treatment for chronic or refractory immune thrombocytopenia are to keep platelets >20 × 10⁹/L and stop bleeding.

Oral manifestations of thrombocytopaenia

The appearance in the mouth of haemorrhagic petechiae, ecchymoses or blood blisters with spontaneous bleeding is suggestive of a haemorrhagic disorder that may be caused either by functional impairment of platelets or of blood vessel walls, by an abnormal decrease in the number of circulating platelets (thrombocytopaenia), or by defects in the blood clotting mechanism. Thrombocytopaenia from decreased production or increased destruction of platelets may be caused by multiple factors including immune mediated mechanisms, drugs or infections.

A diagnosis of thrombocytopaenic purpura can be made when any other disease entity that might be causing the purpura is excluded on the basis of the medical history, the physical examination, a complete blood count and a peripheral blood smear.

In this paper, we outline the clinical features of oral thrombocytopaenic purpura and briefly discuss some aspects of its aetiopathogenesis and treatment.

Immune thrombocytopenia induces autophagy and suppresses apoptosis in megakaryocytes

Immune thrombocytopenia (ITP) is the main pathogenesis of excessive platelet destruction and abnormal megakaryocyte apoptosis, however, the mechanism underlying this abnormality in megakaryocytes remains to be elucidated. Since autophagy and apoptosis are closely interrelated, it can be speculated that the abnormal apoptosis of ITP megakaryocytes is associated with autophagy. To test this hypothesis, a total of 14 patients with ITP and 23 healthy controls were recruited. MEG‑01 cell line was cultured in vitro, and morphological changes were observed by light microscopy, apoptosis was evaluated by flow cytometric analysis of Annexin V‑FITC/propidium iodide staining and western blot analysis of B‑cell lymphoma (Bcl)‑2, Bcl‑associated X protein (Bax), Beclin‑1 and cleaved caspase 3. Apoptotic abnormalities and autophagy were observed in the ITP plasma group. Furthermore, Bax expression was downregulated, while Beclin‑1 was upregulated. Chloroquine can block autophagy induced by ITP and remove the ITP plasma inhibition of apoptosis. Therefore, it may be concluded that ITP may induce autophagy, the inhibition of which may be a novel treatment for ITP.

Circulating myeloid-derived suppressor cells predict disease activity and treatment response in patients with immune thrombocytopenia

Immune thrombocytopenia (ITP) is a disease characterized by isolated thrombocytopenia. Abnormal effector T cell activation is an important mechanism in the pathogenesis of ITP. Regulatory T cells (Treg) have a strong immunosuppressive function for T cell activation and their importance in the pathophysiology and clinical treatment of ITP has been confirmed. Myeloid-derived suppressor cells (MDSCs) are other immunosuppressive cells, which can also suppress T cell activation by secreting arginase, iNOS and ROS, and are essential for Treg cells’ differentiation and maturation. Therefore, we speculate that MDSCs might also be involved in the immune-dysregulation mechanism of ITP. In this study, we tested MDSCs and Treg cells in peripheral blood samples of twenty-five ITP patients and ten healthy donors. We found that MDSCs and Treg cells decreased simultaneously in active ITP patients. Relapsed ITP patients showed lower MDSCs levels compared with new patients. All patients received immunosuppressive treatment including dexamethasone alone or in combination with intravenous immune globulin. We found that MDSCs’ level after treatment correlated with platelet recovery. Our study is the first that focused on MDSCs’ role in ITP. Based on our results, we concluded that circulating MDSCs could predict disease activity and treatment response in ITP patients. This preliminary conclusion indicates a substantial significance of MDSCs in the pathophysiology and clinical treatment of ITP, which deserves further investigation.

Risk factor analysis of autoimmune hemolytic anemia after allogeneic hematopoietic stem cell transplantation in children

Autoimmune hemolytic anemia (AIHA) is a clinically relevant complication after allogeneic hematopoietic stem cell transplantation (HSCT). Currently, there is no established consensus regarding the optimal therapeutic approach. Whether AIHA contributes to increased mortality is still somewhat controversial.We investigated the incidence, risk factors, and outcome of post-transplant AIHA in 265 consecutive pediatric patients undergoing allo-HSCT over a 17-year period. Onset of AIHA was calculated from the first documented detection of AIHA by either clinical symptoms or positive direct agglutinin test. Resolution of AIHA was defined as normalization of hemoglobin and biochemical markers of hemolysis with sustained transfusion independence.We identified 15 cases of AIHA after allo-HSCT (incidence rate, 6%). Ten (67%) of these patients had a positive direct antiglobulin test. Data were obtained for 9 boys and 6 girls after a median follow-up of 53 months (range 4-102). The median age was 5.1 years (range 0.5-15.4) at the time of HSCT and the median time to emergence was 149 days (range 42-273). No significant risk factor for post-transplant AIHA has emerged from our data to date. In the majority (14 of 15; 93%) of AIHA patients, multiple agents for treatment were required, with 12 of 15 (80%) patients achieving complete resolution of AIHA. No splenectomy was performed in any of our patients.For various reasons, post-transplantation AIHA poses an extraordinary challenge to transplant physicians. Despite the advancements in diagnostic tools, therapeutic challenges remain due to the myriad interacting pathways in AIHA.

Efficacy and safety of rituximab in Japanese patients with relapsed chronic immune thrombocytopenia refractory to conventional therapy

Primary immune thrombocytopenia (ITP) is an autoimmune disease mediated by the production of autoantibody against platelets. Rituximab, an anti-CD20 antibody, is reported to be useful for treatment of ITP. In Japan, however, robust evidence on this treatment has not been accumulated. Hence, we conducted this open-label phase III clinical trial to confirm the efficacy and safety of rituximab, administered at 375 mg/m² once per week at weekly intervals for 4 consecutive weeks in Japanese patients with chronic ITP, who had relapsed and were refractory to conventional therapy. The primary endpoint was defined as the percentage of patients with a platelet count above 50 × 10⁹/L at week 24 after the first dose of rituximab, which was 30.8% of 26 patients (95% confidence interval 14.3-51.8%). Although the lower confidence limit of primary endpoint failed to meet the pre-specified threshold of 20%, the clinical efficacy of rituximab is substantial in consideration of the 2% response rate in the placebo arm in other clinical studies in patients with chronic ITP. We conclude that rituximab is clinically useful and safe in the treatment of Japanese patients with chronic ITP, achieving the goal of maintaining platelet count and reducing risk of bleeding while minimizing treatment-related toxicity.

Platelet Abnormalities in the Oral Maxillofacial Surgery Patient

Platelet abnormalities result from a wide range of congenital and acquired conditions, which may be known or unknown to patients presenting for oral maxillofacial surgery. It is critical to obtain a thorough history, including discussion of any episodes of bleeding or easy bruising, to potentially discern patients with an underlying platelet disorder. If patients indicate a positive history, preoperative laboratory studies are indicated, with potential referral or consultation with a hematologist. Appropriate preoperative planning may reduce the risk of bleeding associated with platelet dysfunction, potentially avoiding serious perioperative and postoperative complications.

Role of platelet function and platelet membrane glycoproteins in children with primary immune thrombocytopenia

The aim of the present study was to examine and understand changes in platelet functions prior to and after the treatment of primary immune thrombocytopenia (ITP) in children. An automatic hematology analyzer and whole blood flow cytometry were used to detect immature platelet fraction (IPF), IPC and membrane glycoproteins (CD62p, PAC-1 and CD42b) in ITP children (ITP group), children with complete response after ITP treatment (ITP-CR group) and children with elective surgery (normal control group). The results showed that, levels of platelet count (PLT) and plateletcrit in the ITP group were lower alhtough the levels of mean platelet volume, platelet distribution width and platelet-large cell ratio (P-LCR) were higher than those in the normal control and ITP-CR groups. PLT in the ITP-CR group was lower than that in the normal controls. Additionally, IPF% was higher in the normal control and ITP-CR groups, IPC was lower in the ITP group compared to the normal control and ITP-CR groups. Furthermore, prior to ADP activation, the expression levels of CD62p, PAC-1 and CD42b in the ITP group were lower in ITP group than those in the normal control and ITP-CR groups. The expression level of PAC-1 was lower in the ITP-CR and normal control groups. No differences were identified in CD62p and CD42b expression levels. Following ATP activation, CD62p, PAC-1 and CD42b expression in the ITP group was lower than that in the normal control and ITP-CR groups. PAC-1 expression was lower while CD62p expression was higher in the ITP-CR group compared to the normal control group. In conclusion, the activation of platelets in ITP children was low. Decreased platelet function, platelet parameters and platelet glycoproteins may be used as markers for monitoring the treatment efficacy in ITP children.

Have splenectomy rate and main outcomes of ITP changed after the introduction of new treatments? A monocentric study in the outpatient setting during 35 years

In the last years, rituximab (RTX) and agonists of the thrombopoietin receptor (TPO-R) eltrombopag and romiplostim have provided new treatment options in persistent and chronic immune thrombocytopenia (ITP). Here, we analyzed the changes in therapeutic choices over time and their impact on clinical outcomes in a cohort of 557 ITP outpatients followed at the "L. and A. Seràgnoli" Institute of Hematology, Bologna, Italy, from 1980 to 2015. Overall 397 patients (71%) required front-line corticosteroids, mainly prednisone. Over the decades, splenectomy was delayed from second to third-line, but was steadily used in around 15-25% of patients refractory or relapsing after first-line treatment. Consensually, RTX and TPO-R agonists emerged as second and third-line therapy of choice, respectively. Splenectomy was associated with the best response rates and the lower incidences of relapse, while the relapse rate after RTX was comparable to that observed with corticosteroids and other immunosuppressive agents. The introduction of TPO-R agonists gave an alternative to the administration of immunosuppressive drugs and probably contributed to moderate the incidence of infectious complications that remained stable over the decades, despite an increasing use of RTX from the 2000s onwards. Overall responses were similar over time, with over 97% achieving a response in all time-periods. However, the cumulative risk of bleeding significantly decreased [14.3% (1980-89) vs. 7% (1990-99) vs. 5.6% (2000-09) vs. 0.2% (2010-15)] (P < 0.001), mainly thanks to the optimization of front-line corticosteroids therapy and to the wider availability of second and third-line therapies.

Danazol induces apoptosis and cytotoxicity of leukemic cells alone and in combination with purine nucleoside analogs in chronic lymphocytic leukemia

Recently, great progress has been achieved in the treatment of chronic lymphocytic leukemia (CLL). However, some patients, particularly older patients with comorbidities or with relapsed/refractory leukemia, still have limited therapeutic options. There is an urgent need to discover less toxic and more effective drugs for CLL patients. Applying new modalities or substances that are widely used for the treatment of other diseases has been reported to improve results in CLL treatment. This study aimed to assess the non-chemotherapeutic drug danazol for its potential to destroy leukemic cells. Leukemic cells, obtained from the peripheral blood and bone marrow of 23 CLL patients, were cultured in the presence of danazol and its combination with the purine nucleoside analogs fludarabine and cladribine and bendamustine. After 24 h of incubation, the rate of apoptosis indicated by active caspase-3 expression, and cytotoxicity indicated by forward light scatter and light scatter analysis, was assessed by flow cytometry. We also measured expression of apoptosis-regulating proteins of BCL family and active caspase 9 and active caspase 8 expressions in leukemic cells. Danazol had a caspase-dependent pro-apoptotic and cytotoxic effect on leukemic cells in a tumor-specific manner. The mechanisms of its action appear to be complex and should be precisely established; however, induction of apoptosis involving both mitochondrial and receptor cascades appears to be most probable. Danazol showed a synergic effect with cladribine, an additive effect with fludarabine, and an infra-additive effect with bendamustine. The rate of danazol-induced apoptosis and cytotoxicity did not differ between patients with better and worse prognostic markers. Our results indicate that danazol may be a potential therapeutic agent for CLL patients alone and in combination with purine analogs.

Accuracy of a New Platelet Count System (PLT-F) Depends on the Staining Property of Its Reagents

Background

Platelet count is essential for the diagnosis and management of hemostasis abnormalities. Although existing platelet count methods installed in common hematology analyzers can correctly count platelets in normal blood samples, they tend to miscount platelets in some abnormal samples. The newly developed PLT-F channel in the XN-Series hematology analyzer (Sysmex) has been reported to be a reliable platelet count system, even in abnormal samples. However, how the PLT-F platelet counting system achieves such accuracy has not been described in scientific articles.

Methods

Isolated platelets, erythrocytes, and fragmented erythrocytes were examined using an automated hematology analyzer. The samples were labeled by combining PLT-F reagents and anti-CD62p, CD63, Grp75, Calreticulin, CD41, or CD61 antibody, and analyzed using confocal laser scanning microscopy or flow cytometry.

Results

The PLT-F system correctly discriminated platelets in erythrocytes. Its reagents strongly stained some intraplatelet organelles labeled with anti-Grp75, but only faintly stained the plasma membrane of both platelets and erythrocytes. Microscopic observation and flow cytometric examination revealed that all of these strongly stained cells were also labeled with platelet-specific anti-CD41 and anti-CD61 antibodies.

Conclusions

This study revealed that the staining property of the PLT-F reagents, by which platelets and fragmented erythrocytes are clearly distinguished, contributes to the platelet-counting accuracy of the PLT-F system.

Seasonal Association of Immune Thrombocytopenia in Adults

BACKGROUND

Immune thrombocytopenia (ITP) is an autoimmune disorder. It is characterized by thrombocytopenia due to thrombocyte destruction mediated by autoantibodies; however, cytotoxic and defective regulatory T-lymphocytes play an important role in its pathogenesis. While childhood ITP is usually acute, self-limiting and generally seasonal in nature, ITP in adults is usually chronic; its relation with seasons has not been studied.

AIMS

We investigated whether months and/or seasons have triggering roles in adults with ITP.

STUDY DESIGN

Descriptive study.

METHODS

A retrospective case review of adult patients with primary ITP diagnosed at various University Hospitals in cities where Mediterranean climate is seen was performed. Demographic data, date of referral and treatments were recorded. Corticosteroid-resistant, chronic and refractory cases were determined. Relation between sex, corticosteroid-resistant, chronic and refractory ITP with the seasons was also investigated.

RESULTS

The study included 165 patients (124 female, mean age=42.8±16.6). Most cases of primary ITP were diagnosed in the spring (p=0.015). Rates of patients diagnosed according to the seasons were as follows: 35.8% in spring, 23% in summer, 20.6% in fall, and 20.6% in winter. With respect to months, the majority of cases occurred in May (18.2%). Time of diagnosis according to the seasons did not differ between genders (p=0.699). First-line treatment was corticosteroids in 97.3%, but 35% of the cases were corticosteroid-resistant. Steroid-resistant patients were mostly diagnosed in the spring (52.1%) (p=0.001). ITP was chronic in 52.7% of the patients and they were also diagnosed mostly in the spring (62.7%) (p=0.149).

CONCLUSION

This is the first study showing seasonal association of ITP in adults and we have observed that ITP in adults is mostly diagnosed in the spring. The reason why more patients are diagnosed in the spring may be due to the existence of atmospheric pollens reaching maximum levels in the spring in places where a Mediterranean climate is seen.

Immune Thrombocytopenic Purpura During Maintenance Phase of Acute Lymphoblastic Leukemia: A Rare Coexistence Requiring a High Degree of Suspicion, a Case Report and Review of the Literature

Thrombocytopenia may develop in patients with acute lymphoblastic leukemia (ALL) due to myelosuppression of chemotherapy or relapse. Here we report a pediatric patient with ALL whose platelet counts decreased at the 102nd week of maintenance treatment. Thrombocytopenia was refractory to platelet infusions and bone marrow aspiration revealed remission status for ALL along with increased megakaryocytes. The cessation of chemotherapy for 2 weeks caused no increase in thrombocyte counts. The viral serology was unrevealing. A diagnosis of immune thrombocytopenic purpura (ITP) was established. After administration of intravenous immunoglobulin, the thrombocytopenia resolved. When thrombocytopenia occurs in patients with ALL in remission, ITP should be kept in mind after exclusion of the more common etiologies.

[Clinical analysis of recombinant human thrombopoietin for 92 adults with severe primary immune thrombocytopenia]

OBJECTIVE

To evaluate the efficacy of recombinant human thrombopoietin (rhTPO) and related factors which influencing the therapeutic effect in adults with severe immune thrombocytopenia (ITP).

METHODS

The efficacy of rhTPO in 92 hospitalized adult patients [35 males and 57 females, median age as 34 (18-65) years] with severe ITP, including 7 cases of newly diagnosed ITP, 29 cases of persistent ITP and 56 cases of chronic ITP from May 2012 to May 2014 was retrospectively investigated. All patients received subcutaneous rhTPO, the injected dosage was 300 U·kg⁻¹·d⁻¹ for 14 days, platelet counts were recorded and followed-up for a week.

RESULTS

The overall response rate of rhTPO treatment was 60.9%. The overall response rates in newly diagnosed, persistent and chronic ITP were 71.4%, 62.1% and 58.9% respectively. The median platelet counts on fourth，seventh, fourteenth days of treatment, and the seventh day of withdrawal were 27(5-49), 65(16-138), 133(28-208) and 67(15-134)×10⁹/L, respectively. The median time was 6(5-7) days when platelet counts reached 100×10⁹/L, the median peak time was 11(5-17) days, the median maximum peak of platelet counts was 194(132-274)×10⁹/L in patients who reached CR after treatment. Related factors which affected therapeutic effect were analyzed in patients who reached CR after treatment, and indicated that sex, age, disease stage, express of platelet membrane glycoprotein (GP) and relative number of CD19+ B, CD3+CD4+ T, CD3+CD8+ T lymphocyte in blood samples did not influence the probability of complete response (P>0.05). A few patients with fever, muscle aches, fatigue or dizziness could be self-recovery without special intervention.

CONCLUSION

Severe ITP in adults treated by rhTPO had satisfactory therapeutic effect and safety.

Successful management of refractory immune thrombocytopenia associated with massive alveolar hemorrhage

Immune thrombocytopenia (ITP) is an acquired immune-mediated disease characterized by persistant thrombocytopenia. Onset of the disease and the clinical course is highly variable, but the disease typically has a benign course. Patients rarely develop serious life-threatening bleeding. Herein, a case with refractory ITP and massive alveolar hemorrhage who was successfully treated with a fast and sequential approach is presented for the first time.