Recommendations for the management of acute immune thrombocytopenia in children. A Consensus Conference from the Italian Association of Pediatric Hematology and Oncology

BACKGROUND

Immune thrombocytopenia (ITP) is an acquired immune-mediated bleeding disorder characterized by isolated thrombocytopenia. Its estimated yearly incidence in the pediatric population is 1.9-6.4/100,000. ITP in children is usually a self-limiting and benign disorder. The clinical management of children with ITP often remains controversial, as robust randomized trials on the management of this disorder are lacking. Treatments vary widely in clinical practice and existing guidelines from hematology societies on clinical management offer indications based largely on expert opinion rather than strong evidence.

MATERIALS AND METHODS

The Coagulative Disorder Working Group of the Italian Association of Pediatric Hematology and Oncology (AIEOP) developed this document to collect shared expert opinions on the management of newly diagnosed ITP, updating previous guidelines and providing recommendations to pediatricians. Each statement has been given a score expressing the strength of evidence, appropriateness and agreement among participants.

RESULTS

Clear-cut definitions of the clinical phases of the disease and clinical response are stated. Recommendations are given regarding the classification of bleeding symptoms, evaluation of bleeding risk, diagnosis, and prognostic factors. Specific recommendations for treatment include indications for first-line (intravenous immunoglobulins, steroids) and second-line (combined therapy, thrombopoietin receptor agonists, immunosuppressive drugs, rituximab) therapeutic agents, as well as hemorrhagic emergency and supportive treatment, including emergency splenectomy. The optimal follow-up schedule, the relation between ITP and vaccines and health-related quality-of-life issues are also discussed.

DISCUSSION

The panel achieved broad consensus on issues related to how to treat children with newly diagnosed ITP, providing a comprehensive review of all relevant clinical aspects.

Long term use of eltrombopag in children with chronic immune thrombocytopenia: extended real life retrospective multicenter experience of the Italian Association of Pediatric Hematology and Oncology

Background

The present multicenter retrospective study on eltrombopag administration in Italian children with chronic ITP aims to extend follow-up of our previous study.

Materials and methods

This retrospective multicenter study was conducted in 17 centers affiliated to the Italian Association of Pediatric Hematology and Oncology (AIEOP). Patients were classified into three subgroups: group 1 included patients who discontinued treatment due to a stable platelet count; group 2 included patients who discontinued treatment due to ineffectiveness; group 3 included patients who did not permanently discontinue treatment.

Results

56 patients were eligible for analysis. The median duration of eltrombopag treatment was 40 months (7-71 months). Twenty patients (36%) discontinued permanently eltrombopag. The reasons of permanent discontinuation were adverse effects (n = 1), inefficacy (n = 10), stable platelet count (n = 9). All patients of group 1 maintained a durable response without additional treatments after eltrombopag discontinuation. We found that patients of group 2 were on treatment for less time (median treatment time: 13.5 months, min: 6.0 - max: 56.0) than patients of group 1 (median treatment time: 34 months, min: 16.0 - max: 62.0) (p < 0.05). Patients of group 2 mostly did not achieve a stable platelet count in the first 6 months of treatment and underwent concomitant therapies during follow-up respect of group 1 and group 3 (p < 0.01).

Conclusion

Our study found that the benefits of eltrombopag treatment, in terms of platelet count improvement and use of additional therapies, are identifiable from the first 6 months of treatment.

Development and Initial Validation of the ONCOREUM Score to Differentiate Childhood Cancer with Arthropathy from Juvenile Idiopathic Arthritis

OBJECTIVE

To develop and validate a weighted score, the ONCOREUM score, that aids physicians in differentiation of cancer with arthropathy from juvenile idiopathic arthritis (JIA).

STUDY DESIGN

Data were extracted from the ONCOREUM Study, a multicenter, cross-sectional investigation aimed at comparing children with cancer and arthropathy to children with JIA. Three statistical approaches were applied to develop the ONCOREUM score and assess the role of each variable in the diagnosis of cancer with arthropathy, including 2 approaches based on multivariable stepwise selection (models 1 and 2) and 1 approach on a Bayesian model averaging method (model 3). The β coefficients estimated in the models were used to assign score points. Considering that not missing a child with cancer is a mandatory clinical objective, discriminating performance was assessed by fixing sensitivity at 100%. Score performance was evaluated in both developmental and validation samples (representing 80% and 20% of the study population, respectively).

RESULTS

Patients with cancer and arthropathy (49 with solid tumors and 46 with hematologic malignancies without peripheral blasts) and 677 patients with JIA were included. The highest area under the receiver operating characteristic (ROC) curve (AUC) in the validation data set was yielded by model 1, which was selected to constitute the ONCOREUM score. The score ranged from -18 to 21.8, and the optimal cutoff obtained through ROC analysis was -6. The sensitivity, specificity, and AUC of the cutoff in the validation sample were 100%, 70%, and 0.85, respectively.

CONCLUSIONS

The ONCOREUM score is a powerful and easily applicable tool that may facilitate early differentiation of malignancies with articular complaints from JIA.

Pathogenesis of Autoimmune Cytopenias in Inborn Errors of Immunity Revealing Novel Therapeutic Targets

Autoimmune diseases are usually associated with environmental triggers and genetic predisposition. However, a few number of autoimmune diseases has a monogenic cause, mostly in children. These diseases may be the expression, isolated or associated with other symptoms, of an underlying inborn error of immunity (IEI). Autoimmune cytopenias (AICs), including immune thrombocytopenic purpura (ITP), autoimmune hemolytic anemia (AIHA), autoimmune neutropenia (AN), and Evans’ syndrome (ES) are common presentations of immunological diseases in the pediatric age, with at least 65% of cases of ES genetically determined. Autoimmune cytopenias in IEI have often a more severe, chronic, and relapsing course. Treatment refractoriness also characterizes autoimmune cytopenia with a monogenic cause, such as IEI. The mechanisms underlying autoimmune cytopenias in IEI include cellular or humoral autoimmunity, immune dysregulation in cases of hemophagocytosis or lymphoproliferation with or without splenic sequestration, bone marrow failure, myelodysplasia, or secondary myelosuppression. Genetic characterization of autoimmune cytopenias is of fundamental importance as an early diagnosis improves the outcome and allows the setting up of a targeted therapy, such as CTLA-4 IgG fusion protein (Abatacept), small molecule inhibitors (JAK-inhibitors), or gene therapy. Currently, gene therapy represents one of the most attractive targeted therapeutic approaches to treat selected inborn errors of immunity. Even in the absence of specific targeted therapies, however, whole exome genetic testing (WES) for children with chronic multilineage cytopenias should be considered as an early diagnostic tool for disease diagnosis and genetic counseling.

"CHildren with Inherited Platelet disorders Surveillance" (CHIPS) retrospective and prospective observational cohort study by Italian Association of Pediatric Hematology and Oncology (AIEOP)

BACKGROUND

Inherited thrombocytopenias (ITs) are rare congenital bleeding disorders characterized by different clinical expression and variable prognosis. ITs are poorly known by clinicians and often misdiagnosed with most common forms of thrombocytopenia.

MATERIAL AND METHODS

"CHildren with Inherited Platelet disorders Surveillance" study (CHIPS) is a retrospective - prospective observational cohort study conducted between January 2003 and January 2022 in 17 centers affiliated to the Italian Association of Pediatric Hematology and Oncology (AIEOP). The primary objective of this study was to collect clinical and laboratory data on Italian pediatric patients with inherited thrombocytopenias. Secondary objectives were to calculate prevalence of ITs in Italian pediatric population and to assess frequency and genotype-phenotype correlation of different types of mutations in our study cohort.

RESULTS

A total of 139 children, with ITs (82 male - 57 female) were enrolled. ITs prevalence in Italy ranged from 0.7 per 100,000 children during 2010 to 2 per 100,000 children during 2022. The median time between the onset of thrombocytopenia and the diagnosis of ITs was 1 years (range 0 - 18 years). A family history of thrombocytopenia has been reported in 90 patients (65%). Among 139 children with ITs, in 73 (53%) children almost one defective gene has been identified. In 61 patients a pathogenic mutation has been identified. Among them, 2 patients also carry a variant of uncertain significance (VUS), and 4 others harbour 2 VUS variants. VUS variants were identified in further 8 patients (6%), 4 of which carry more than one variant VUS. Three patients (2%) had a likely pathogenic variant while in 1 patient (1%) a variant was identified that was initially given an uncertain significance but was later classified as benign. In addition, in 17 patients the genetic diagnosis is not available, but their family history and clinical/laboratory features strongly suggest the presence of a specific genetic cause. In 49 children (35%) no genetic defect were identified. In ninetyseven patients (70%), thrombocytopenia was not associated with other clinically apparent disorders. However, 42 children (30%) had one or more additional clinical alterations.

CONCLUSION

Our study provides a descriptive collection of ITs in the pediatric Italian population.

Association of Immune Thrombocytopenia and Celiac Disease in Children: A Retrospective Case Control Study

Objective:

The association between celiac disease (CD) and immune thrombocytopenia (ITP) is still uncertain. The aim of this study was to characterize the coexistence of these two diseases in Italian children.

Materials and Methods:

This is a retrospective multicenter study investigating the occurrence of CD in 28 children with ITP diagnosed from January 1, 2000, to December 31, 2019.

Results:

The first diagnosis was ITP in 57.1% and CD in 32.1% of patients. In 3 patients (10.7%), the two diagnoses were simultaneous. All the potential and silent cases of CD in our cohort were diagnosed in the groups of “ITP first” and “simultaneous diagnosis”. In all children ITP was mild, and in 2 out of 8 not recovered from ITP at the time of CD diagnosis a normalization of platelet counts (>100,000/μL) occurred 3 and 5 months after starting a gluten-free diet, respectively.

Conclusion:

We think that screening for CD should be considered in children with ITP regardless of the presence of gastrointestinal symptoms. Furthermore, some patients may recover from ITP after starting a gluten-free diet.

Musculoskeletal manifestations of childhood cancer and differential diagnosis with juvenile idiopathic arthritis (ONCOREUM): a multicentre, cross-sectional study

BACKGROUND

Presenting symptoms of childhood cancers might mimic those of rheumatic diseases. However, the evidence available to guide differential diagnosis remains scarce. Preventing wrong or delayed diagnosis is therefore important to avoid incorrect administration of glucocorticoid or immunosuppressive therapy and worsening of prognosis. As such, we aimed to assess the prevalence and characteristics of presenting musculoskeletal manifestations in patients at cancer onset and to identify the factors that differentiate childhood malignancies with arthropathy from juvenile idiopathic arthritis.

METHODS

We did a multicentre, cross-sectional study at 25 paediatric haemato-oncology centres and 22 paediatric rheumatology centres in Italy. We prospectively recruited patients who were younger than 16 years that were newly diagnosed with cancer or juvenile idiopathic arthritis. We excluded patients with glucocorticoid pre-treatment (>1 mg/kg per day of oral prednisone or equivalent for ≥2 consecutive weeks). We collected data for patients with a new diagnosis of cancer or juvenile idiopathic arthritis using an electronic case report form on a web-based platform powered by the Cineca Interuniversity Consortium. The primary outcome was to describe the frequency and characteristics of musculoskeletal manifestations at cancer onset; and the secondary outcome was to identify factors that could discriminate malignancies presenting with arthropathy, with or without other musculoskeletal symptoms, from juvenile idiopathic arthritis using multivariable logistic regression analysis.

FINDINGS

Between May 1, 2015, and May 31, 2018, 1957 patients were eligible, of which 1277 (65%) had cancer and 680 (35%) had juvenile idiopathic arthritis. Musculoskeletal symptoms occurred in 324 (25% [95% CI 23·0-27·8]) of 1277 patients with cancer, of whom 207 had arthropathy. Patients with malignant bone tumours had the highest frequency of musculoskeletal symptoms (53 [80%] of 66), followed by patients with Langerhans histiocytosis (16 [47%] of 34), leukaemia (189 [32%] of 582), soft-tissue sarcomas (16 [24%] of 68), and neuroblastoma (21 [19%] of 109). In the 324 patients with cancer and musculoskeletal symptoms, the most common complaints were joint pain (199 [61%]), followed by limb bone pain (112 [35%]). Joint involvement had a prevalent monoarticular pattern (100 [48%] of 207) and oligoarticular pattern (86 [42%] had 2-4 joints involved and 20 [10%] had >4 joints involved), with the most frequently involved joints being the hip (88 [43%] of 207) and knee (81 [39%]). On multivariable analysis, limb bone pain was the independent variable most strongly associated with cancer (odds ratio [OR] 87·80 [95% CI 18·89-408·12]), followed by weight loss (59·88 [6·34-565·53]), thrombocytopenia (12·67 [2·40-66·92]), monoarticular involvement (11·30 [4·09-31·19]), hip involvement (3·30 [1·13-9·61]), and male sex (2·40 [1·03-5·58]). Factors independently associated with juvenile idiopathic arthritis were morning stiffness (OR 0·04 [95% CI 0·01-0·20]), joint swelling (0·03 [0·01-0·09]), and involvement of the small hand joints (0·02 [0-1·05]).

INTERPRETATION

Our study provides detailed information about presenting musculoskeletal manifestations of childhood cancers and highlights the clinical and laboratory features that are most helpful in the differential diagnosis with juvenile idiopathic arthritis.

FUNDING

Associazione Lorenzo Risolo.

HbS/β+ thalassemia: Really a mild disease? A National survey from the AIEOP Sickle Cell Disease Study Group with genotype-phenotype correlation

OBJECTIVES

HbS/β+ patients' presence in Italy increased due to immigration; these patients are clinically heterogeneous, and specific guidelines are lacking. Our aim is to describe a cohort of HbS/β+ patients, with genotype-phenotype correlation, in order to offer guidance for clinical management of such patients.

METHODS

Retrospective cohort study of HbS/β+ patients among 15 AIEOP Centres.

RESULTS

A total of 41 molecularly confirmed S/β+ patients were enrolled (1-55 years, median 10.9) and classified on β+ mutation: IVS-I-110, IVS-I-6, promoter, and "others." Prediagnostic events included VOC 16/41 (39%), ACS 6/41 (14.6%), sepsis 3/41 (3.7%), and avascular necrosis 3/41 (7,3%). Postdiagnostic events were VOC 22/41 (53.6% %), sepsis 4/41 (9.7%), ACS 4/41 (9.7%), avascular necrosis 3/41 (7.3%), aplastic crisis 2/41 (4.8%), stroke 1/41 (2.4%), ACS 1/41 (2.4%), and skin ulcerations 1/41 (2.4%). The IVS-I-110 group presented the lowest median age at first SCD-related event (P = .02 vs promoter group) and the higher median number of severe events/year (0.26 events/patient/year) (P = .01 vs IVS-I-6 and promoter groups). Promoter group presented a specific skeletal phenotype. Treatment regimen applied was variable among the centers.

CONCLUSIONS

HbS/β+ is not always a mild disease. Patients with IVS-I-110 mutation could benefit from a standard of care like SS and S/β° patients. Standardization of treatment is needed.