Clinical trial NCT03810352: Association of Platelet Parameters With Bleeding Severity in Children With ITP
Official title: Association of Platelet Parameters Identified by the Sysmex XN-1000 and Flow Cytometry With Concurrent and Subsequent Bleeding Severity in Children With Immune Thrombocytopenia (ITP): A Multicenter Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Immune Thrombocytopenia
Keywords: ITP
platelet function
Sysmex
Lead sponsor: Boston Children's Hospital
Sponsor class: OTHER
Collaborators: name: Sysmex America, Inc.
name: Children's Hospital Colorado
name: Children's Hospital of Philadelphia
name: Baylor College of Medicine
name: Columbia University
name: Duke University
First posted: 2019-01-18
Enrollment: 95
Sex: ALL
Minimum age (years): 6
Maximum age (years): 20
Standard ages: CHILD
ADULT
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Pediatric patients diagnosed with primary or secondary immune thrombocytopenia.

Brief summary: Patients with severe immune thrombocytopenia (ITP) present with similarly low platelet counts but varying bleeding symptoms, making it difficult to predict the disease course and to decide on an appropriate treatment plan. In a single-center study, platelet parameters including the immature platelet fraction, the absolute immature platelet count , and functional response markers were found to be significantly associated with patient bleeding severity, independent of platelet count. This study aims to confirm and replicate these findings in a multi-center patient population and to investigate the use of these parameters to better predict disease severity and bleeding events.

Detailed description: Many children with severe immune thrombocytopenia (ITP) present with mild symptoms and their disease spontaneously resolves within 3 to 6 months. However, a subset of pediatric ITP patients experience severe bleeds and their symptoms persist for more than 6 to 12 months. Both patient populations present with similarly low platelet counts, making it difficult to predict the disease course and to decide on a treatment plan. The current American Society of Hematology treatment guidelines advise that most cases of ITP may be managed through close observation, while pharmacological interventions that may result in treatment-related toxicities may be used in patients with more severe bleeding symptoms. In order to improve the care and management of pediatric patients with ITP, it is necessary to develop a better predictor of bleeding events and disease severity than the patient's platelet count.

In a previous single-center study, investigators studied the association of different platelet parameters with patient bleeding severity. Using whole blood from patients diagnosed with severe ITP, investigators measured the immature platelet fraction (IPF) and absolute immature platelet count (IPC) through a hematology analyzer (Sysmex XN-1000). Investigators performed functional tests on the platelets and analyzed them through flow cytometry. In this study, the investigators found that the IPF and IPC is associated with patient bleeding severity, independent of platelet count. It was also determined that functional activation markers such as P-selectin and glycoprotein (GP) IIb-IIIa are significantly associated with subsequent bleeding severity in children, independent of platelet count. The results of these proposed studies in ITP patients may suggest clinically relevant uses of these assays.

To confirm these findings, this trial will repeat the previous study in a multi-center patient population, including a greater number of patients with severe bleeding and low platelet counts.

Eligibility criteria: Inclusion Criteria:

* Diagnosed with primary or secondary immune thrombocytopenia.
* Platelet count of \< 50 x 10\^9/L

Exclusion Criteria:

* May not have received aspirin 10 days prior to study entry.
* May not have received nonsteroidal anti-inflammatory drugs (NSAIDs) 3 days prior to study entry.

Primary outcomes:
measure: Association of IPF with concurrent, subsequent and worst-ever bleeding in children with ITP.
timeFrame: February 2019-August 2022
measure: Association of IPC with concurrent, subsequent, and worst-ever bleeding in children with ITP
timeFrame: February 2019-August 2022
measure: Association of platelet function markers with concurrent, subsequent, and worst-ever bleeding in children with ITP.
timeFrame: February 2019-August 2022
Secondary outcomes:
Other outcomes:
Locations:
city: Aurora
country: United States
facility: Children's Hospital Colorado
state: Colorado
city: Boston
country: United States
facility: Boston Children's Hospital
state: Massachusetts
city: New York
country: United States
facility: Columbia University Medical Center
state: New York
city: Durham
country: United States
facility: Duke University Medical Center
state: North Carolina
city: Philadelphia
country: United States
facility: Children's Hospital of Philadelphia
state: Pennsylvania
city: Houston
country: United States
facility: Baylor College of Medicine
state: Texas
Study officials:
References: