Prader-Willi syndrome: is there a recognizable fetal phenotype?
Nicole Bigi1, Jean-Michel Faure, Christine Coubes
1Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Service de Génétique Médicale, Hôpital Arnaud de Villeneuve, Centre Hospitalier Régional et Universitaire, Montpellier, France.
Prenatal Diagnosis
|July 29, 2008
Summary
Prenatal ultrasound may identify Prader-Willi syndrome (PWS) through specific fetal features. Diminished movement, polyhydramnios, and limb positioning can suggest PWS, aiding early diagnosis.
Area of Science:
- Medical Genetics
- Prenatal Diagnosis
- Fetal Ultrasound
Background:
- Prader-Willi syndrome (PWS) is a complex genetic disorder.
- Early diagnosis of PWS is crucial for timely intervention and management.
- Identifying PWS prenatally can significantly impact perinatal care.
Observation:
- Two cases of PWS diagnosed during pregnancy were analyzed.
- Ultrasound revealed diminished fetal movement, polyhydramnios, and characteristic limb positioning.
- Specific fetal appearance noted around 28-30 weeks gestation.
Findings:
- Case 1: Deletion in the 15q11-q13 region confirmed PWS via methylation studies.
- Case 2: Uniparental disomy identified through abnormal methylation patterns.
- Consistent ultrasound findings across both cases included flexed wrists, dorsi-extended feet, and flexed toes.
Implications:
- The combination of diminished fetal movement, polyhydramnios, and peculiar extremity positioning is a strong indicator for PWS.
- These ultrasound findings can prompt further genetic investigation for prenatal PWS diagnosis.
- Improved prenatal detection of PWS allows for better-prepared delivery and postnatal care planning.
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