Makindo Medical Notes

Patau Syndrome (Trisomy 13) 👶🧬: A rare, severe chromosomal disorder caused by an extra copy of chromosome 13. Most infants survive only days to weeks due to multiple congenital malformations.

About ℹ️

• Incidence: ~1 in 10,000 live births.
• Mean survival time: 2–3 days (most die within the first weeks of life).
• Usually sporadic, not inherited.
• Risk ↑ with advanced maternal age.

Clinical Features 👩‍⚕️

• Brain: Holoprosencephaly (failure of forebrain to divide).
• Limbs: Polydactyly (extra fingers/toes), flexed fingers, rocker-bottom feet 👣.
• Face: Cleft lip ± cleft palate.
• Heart: Severe congenital cardiac defects (e.g., VSDs, PDA).
• Neural tube defects: Spina bifida, anencephaly may occur.
• Severe developmental delay & growth restriction.

Key Differentials 🧩

• Edwards Syndrome (Trisomy 18) – overlapping features (clenched hands, rocker-bottom feet).
• Down Syndrome (Trisomy 21) – less severe, distinctive facies, intellectual disability.
• Other multiple congenital anomaly syndromes.

Investigations 🔬

• Karyotyping: Definitive test confirming Trisomy 13.
• Prenatal: Ultrasound → facial/brain/heart anomalies; NIPT detects extra chromosome 13.
• CVS / Amniocentesis: for prenatal confirmation.

Management ❤️

• Supportive & palliative care: No curative treatment.
• Multidisciplinary input: Neonatology, cardiology, neurology, surgery, and genetics.
• Palliative approach: Prioritises comfort, dignity, and family support.
• Genetic counselling for parents (recurrence risk usually low, but maternal age is a factor).

Prognosis 📈

• Most affected infants die within the first month.
• Rare survivors often have profound neurodevelopmental impairment.

References 📚

• Genetics Home Reference – Patau Syndrome
• NCBI – Patau Syndrome Overview

💡 Exam Pearl

Think “13 = unlucky” 🍀❌: Severe, often fatal congenital anomalies (holoprosencephaly, polydactyly, cleft lip/palate, congenital heart disease). Karyotype is diagnostic ✅.