X-Linked dominant chondrodysplasia punctata: prenatal diagnosis and autopsy findings.
OBJECTIVE
To report our experience of the prenatal diagnosis of X-linked dominant chondrodysplasia punctata (CDPX2) and highlight its variable phenotypic presentation.


METHODS
We report the sonographic features of three female fetuses affected with CDPX2. The ultrasound, radiographic and pathological findings were compared.


RESULTS
Family 1: Two affected pregnancies, both terminated. Fetus 1: Presented with epiphyseal stippling involving the vertebrae, upper and lower limbs, asymmetric shortening of the long bones and flat facial profile. Fetus 2: Prenatal findings included premature epiphyseal stippling, paravertebral cartilaginous calcific foci, mild shortening of the long bones and flat facies. Mutation analysis of the mother and both fetuses revealed mutation in the emopamil-binding protein (EBP) gene. Family 2: Prenatal sonography showed scattered epiphyseal stippling, minimal vertebral segmentation anomalies, mild asymmetric limb shortening and flat facies. Female infant delivered at 39 weeks of gestation. Biochemical analysis in all three fetuses showed increased levels of serum 8(9)-cholestenol consistent with delta (8), delta (7)-isomerase deficiency and CDPX2.


CONCLUSIONS
Prenatal diagnosis of CDPX2 is difficult because of marked phenotypic variation. Epiphyseal stippling, ectopic paravertebral calcifications, asymmetric shortening of long bones and dysmorphic flattened facies are crucial for prenatal diagnosis. DNA analysis of the CDPX2 gene and biochemical determination of the serum 8(9)-cholestenol level are important for diagnosis, especially if future pregnancies are planned.
Umranikar
Shalini
S
Department of Medical Imaging, Women's College Campus, Sunnybrook and Women's Health Sciences Center, University of Toronto, Toronto, Ontario, Canada. shaliniumranikar@gmail.com
Glanc
Phyllis
P
Unger
Sheila
S
Keating
Sarah
S
Fong
Katherine
K
Trevors
Christopher D
CD
Myles-Reid
Diane
D
Chitayat
David
D
D000015:Abnormalities, Multiple; D000328:Adult; D001344:Autopsy; D002784:Cholesterol / Q000097:blood; D002806:Chondrodysplasia Punctata / Q000000981:diagnostic imaging* / Q000201:enzymology / Q000235:genetics*; D041321:Chromosomes, Human, X; D004252:DNA Mutational Analysis; D005192:Family Health; D017809:Fatal Outcome; D005260:Female; D005799:Genes, Dominant / Q000235:genetics*; D005865:Gestational Age; D006801:Humans; D010641:Phenotype; D011247:Pregnancy; D013251:Steroid Isomerases / Q000172:deficiency / Q000235:genetics; D016216:Ultrasonography, Prenatal
D002784:Cholesterol; D013251:Steroid Isomerases; C022669:delta(8)-delta(7)-sterol isomerase; C090445:EBP protein, human