Coagulation Abnormalities in Patients with Noonan Syndrome - a Single Centre Case Series.
Notice bibliographique
Résumé
Abstract Noonan syndrome (NS) is an autosomal dominant disorder that includes short stature, characteristic facies, congenital heart defect, webbed neck, and developmental delay. A mutation in the PTPN11 gene can be identified in 50% of patients. A bleeding tendency is included in the phenotypic spectrum, with factor XI deficiency and platelet abnormalities described most frequently. At Winnipeg’s Health Sciences Centre, 24 patients with features typical of NS have been studied by the Special Haemostasis Laboratory. Four patients in whom the diagnosis was suspected but not considered definite are also included in this analysis. Clinical complaints included easy bruising (9), epistaxis (2), menorrhagia (1), and a family history of bleeding problems (3). Sixteen patients were referred for investigation following the diagnosis of NS. All 28 patients had coagulation screening tests: 16 patients had an abnormal PT and 12 had an abnormal aPTT. Thrombin time was slightly prolonged in 6 of 23 patients. Reptilase time was normal in 8 patients, and fibrinogen concentration was normal in 20 patients. Factor XI levels were measured in 14 patients, with a mean value of 62% (range 32–99%). Only 2 patients had levels below the normal range. One of 13 patients evaluated for FXII levels was deficient (FXII 25%), and 2 of 19 patients evaluated for FIX levels had mild FIX deficiency (FIX 40 and 49%) without symptomatic bleeding. No other factor deficiencies were identified. Twenty-four patients had determinations of von Willebrand Factor antigen and activity; 2 had results consistent with mild Type 1 von Willebrand Disease. Platelet aggregation studies were done in 22 patients. A variety of abnormalities were noted, with the most frequent being abnormal aggregation with epinephrine (7/22). Dense granule number was decreased in 2 of 7 samples studied by electron microscopy. Lupus anticoagulants were detected in 3 of 13 patients screened. Thrombophilia investigations in 4 patients detected decreased protein S in one patient who had been diagnosed previously with protein S deficiency. This unselected case series, the largest reported to date in the literature, illustrates the heterogeneity of coagulation abnormalities that may occur in NS. Symptoms, when present, were mild, and often did not correlate with laboratory abnormalities. Non-specific platelet aggregation defects were the most commonly identified abnormalities. In contrast to the literature, factor XI deficiency was not prevalent. A specific etiology for the variable bleeding tendency has not yet been identified in NS.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,003 |
| Méta-épidémiologie (sens strict) | 0,002 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,002 | 0,002 |
| Études des sciences et des technologies | 0,002 | 0,001 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,002 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,004 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».