Link Between Abnormal Bleeding and Coagulation Disorders in Noonan Syndromes
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Reuse of routine clinical and biological data.
- Who it may be relevant to
- Registry conditions: Noonan Syndrome. Basic parameters: No limits · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- France
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Hemorrhagic Risk and Hemostasis Disorders in Noonan Syndrome and Related Conditions
Overview
Noonan syndrome is a relatively rare genetic disorder, affecting around 1 in every 1,000 to 2,500 children born. Patients often have a tendency to bleed more easily, particularly from the skin or mucocutaneous tissue (such as mouth or nose). Around half of all the patients are affected by bleedings. The causes of bleeding are variable : some are linked to platelet disorders, others to more complex coagulation problems. However, it is difficult to predict exactly which patients are at risk of severe bleeding, for example during surgery. This is why there are as yet no clear recommendations for preventing this risk before medical intervention. However, it is recommended that patients with Noonan syndrome consult a specialist to assess this risk. Unfortunately, the tests carried out are often unreliable in predicting this significant risk of bleeding. In this study, data from a large group of patients with Noonan syndrome, followed-up in different centers in France, will be studied. During a medical meeting as part of their regular follow-up, a medical doctor assessed their tendency to bleed using a standardized questionnaire (standardized ISTH-BAT score). These results will be compared with the biological tests also performed during their medical follow-up. The aim is to better understand whether these tests are useful in predicting the risk of bleeding. Ultimately, this could help practicians to better anticipate surgical or medical interventions in these patients, and limit bleeding-related risk.
Detailed description
Noonan syndrome (NS) is an autosomal dominant genetic disorder, with an estimated prevalence of 1 in 1,000 to 2,500 births/year. Patients with NS have a cutaneous-mucosal hemorrhagic diathesis, with a prevalence estimated at 46% in a large meta-analysis. The most frequently reported abnormalities are those of primary hemostasis (thrombocytopenia, thrombopathy and Willebrand's disease), as well as those of coagulation, but the correlation between symptomatology and hemostatic disorders is unclear. As a result, there are no specific recommendations in terms of intraoperative hemorrhagic risk prevention, due to a lack of knowledge of the real hemorrhagic risk in these patients, who are particularly exposed to invasive procedures. The PNDS recommends that patients be referred to a haemostasis specialist for assessment of bleeding risk, which entails the performance of investigations that are often not very predictive of bleeding risk. Interpretation of these results with regard to bleeding risk therefore remains unsolved. It is against this backdrop that the aim of this study is to retrospectively collect the bleeding diathesis of a national cohort of patients with SN, using a standardized ISTH-BAT score, performed in the context of a specialized hemostasis consultation by a physician from one of the centers involved in this study. The hemorrhagic diathesis will be compared with the results of the hemostasis exploration performed as part of their follow-up (routine care). This study will make it possible to assess the value of a hemostasis study in predicting the risk of bleeding in these patients.
Interventions
- Other Reuse of routine clinical and biological data
Reuse of routine clinical and biological data
Primary outcome measures
- ISTH-BAT haemorrhagic score [Time frame: At first clinical visit in the referent center (retrieved retrospectively at inclusion visit)]
- Willebrand factor [Time frame: At first clinical visit in the referent center (retrieved retrospectively at inclusion visit)]
- Platelet function [Time frame: At first clinical visit in the referent center (retrieved retrospectively at inclusion visit)]
Eligibility criteria
Inclusion criteria
- All patients with SN, regardless of age
- Patient/parental guardians informed of the study
- Patient/legal representative not opposed to the use of their/the child's data
- Person affiliated or benefiting from a social security scheme
Exclusion criteria
\- Adults protected by law (guardianship, curatorship or safeguard of justice)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
France · 1 center
- CHU de Bordeaux, Service Hématologie Biologique — Bordeaux
Identifiers
NCT: NCT07259135 · CHUBX 2024/96