Physiology & Biochemistry · patient case question
Downslanting palpebral fissures, malar hypoplasia and malformed external ears characterise which syndrome?
Patient case: Syndromes recognised at the chair
demo: Paediatric and young adult clinic
chief: Several patients whose facial and dental features point to a recognisable syndrome.
history: One child has bilateral painless expansion of the mandibular angles with an upward gaze, and a father with the same childhood history. Another has downslanting palpebral fissures, malar hypoplasia and malformed external ears. A third has notched, screwdriver-shaped permanent incisors and multicusped first molars. A fourth has a smooth philtrum, a thin upper lip and short palpebral fissures.
meds: None.
findings: Not applicable.
Show answer and explanation
Correct answer: D. Treacher Collins syndrome
- A. Crouzon syndrome features craniosynostosis with midface hypoplasia, proptosis from shallow orbits and a Class III relationship, but the ears are typically normal.
- B. Pierre Robin sequence is the triad of micrognathia, glossoptosis and cleft palate, without the ear and zygomatic anomalies.
- C. Apert syndrome combines craniosynostosis with symmetrical syndactyly of the hands and feet, which is its distinguishing feature.
- D. Correct. Treacher Collins syndrome, or mandibulofacial dysostosis, results from defective first and second branchial arch development, usually from TCOF1 mutations. It gives downslanting palpebral fissures with lower lid colobomas, zygomatic and mandibular hypoplasia, external ear malformation with conductive hearing loss, and often cleft palate.
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