Prenatal Evidence of Persistent Notochord and Absent Sacrum Caused by a Mutation in the T (Brachyury) Gene

Table 1

Prenatal ultrasound features of caudal regression syndrome: the findings observed in our series are italics.

First trimester

(i) Abnormal appearance of the yolk sac^2; (ii) Shorter CRL than expected for the gestational age^2; (iii) Increased nuchal translucency^2; (iv) Sacral agenesis^2

Second and third trimester

Spine: (i) Partial or complete absence of sacrum and sacral vertebrae^2; (ii) Scoliosis and kyphosis^1; (iii) Abnormal vertebral ossification; (iv) Decreased interspace between femoral heads^1; Limbs: (i) Clubfeet^1; (ii) Flexion contractures of the lower extremities^1; (iii) Syndactyly/polydactyly^1; CNS: (i) Spina bifida, meningocele, or myelomeningocele^1; (ii) Hydrocephaly^2; (iii) Microcephaly, anencephaly, or holoprosencephaly^1; Face: (i) Pierre Robin syndrome^1; (ii) Facial clefts^1; Cardiac: (i) Ventricular septal defect^1; (ii) Transposition of great vessels^1; (iii) Dextrocardia^1; (iv) Coarctation of the aorta^1; GU tract: (i) Renal agenesis^1; (ii) Renal dysplasia^1; (iii) Hydronephrosis^1; (iv) Dilated/ectopic ureters^1; (v) Ambiguous genitalia, hypospadias^1; (vi) Vesical/cloacal exstrophy^1; (vii) Absent bladder^1; (viii) Enlarged and thick-walled bladder; GI tract: (i) Abdominal wall defect^1

CNS: central nervous system; GU: genitourinary; GI: gastrointestinal. ¹Boulas [1]; ²Singh et al. [2].