A neonate has microcephaly, prominent occiput, overlapping fingers (index over middle, fifth over fourth), rocker-bottom feet, ventricular septal defect, and omphalocele. Chromosomal analysis would most likely show:
- A Trisomy 21
- B Trisomy 13 (Patau syndrome)
- C Trisomy 18 (Edwards syndrome) ✓
- D Turner syndrome (45,X)
Correct answer: C. Trisomy 18 (Edwards syndrome)
Explanation
The clinical constellation of prominent occiput, characteristic overlapping of fingers (index overlapping third, fifth overlapping fourth — the 'clenched fist' deformity), rocker-bottom feet, VSD, and omphalocele is classic for trisomy 18 (Edwards syndrome). Trisomy 13 (Patau) features holoprosencephaly, cleft lip/palate, polydactyly, and cutis aplasia. Trisomy 21 presents with upslanting palpebral fissures, flat nasal bridge, single palmar crease, and hypotonia. Turner syndrome shows webbed neck, lymphoedema, and coarctation of aorta.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.