OBGYN.net Ultrasound: Case of the Month August 1998

Chondroectodermal Dysplasia Diagnosed by First Trimester Ultrasound

Julia A. Drose, BA, RDMS, RDCS, RVT
Assistant Professor
Division of Ultrasound
University of Colorado Health Sciences Center
Denver, Colorado

Introduction:

Chondroectodermal dysplasia, or Ellis-van Creveld syndrome, is an autosomal recessive disorder with an incidence of approximately 1 out of 150,000 live births.1 A higher prevalence has been reported among certain populations such as the Amish and the Arabs of the Gaza strip.2 Major diagnostic criteria in affected fetuses includes postaxial polydactyly of the hands (100%), mild to moderate limb shortening with a mesomelic predominance and dysplastic fingernails.2,3 Other associated anomalies include postaxial polydactyly of the feet (10-25%), ribs that are short and horizontal in orientation, Dandy-Walker malformation, hydrocephalus, cleft palate, fusion between the upper lip and gum, situs inversus, lobar emphysema, nephrocalcinosis, neonatal gallstones, and genital anomalies.2,4,5 Congenital heart disease occurs in 50-60% of cases, most commonly a large atrial septal defect.6,7 Chondroectodermal dysplasia is generally a non-lethal disorder with 2/3 of patients surviving to adulthood. Death prior to 6 months of age has been reported in approximately 1/3 of cases, usually due to cardiac malformations or pulmonary hypoplasia.2


History:

A 35 year old women, G3,P2, was referred for an ultrasound at 12 weeks gestational age. Her first child was affected with Ellis-van Creveld Syndrome. Her second child was unaffected.


Findings:
Figure1: Fetal right hand displaying 6 digits.
Figure 2: Fetal left hand displaying 6 digits.
Figure 3: Fetal right humerus measuring 5.3mm, consistent with short-limb dysplasia.
Figure 4: Fetal right radius measuring 3.5mm, consistent with short-limb dysplasia.
Figure 5: Abnormal fetal heart thought to be an atrioventricular canal defect, but a definitive diagnosis could not be made at this early gestation.
(Click on each image to view larger version)

Outcome:

Because of the patients previous history of a child with chondroectodermal dysplasia, that again was thought to be the most likely diagnosis. The patient elected to terminate the fetus.

Prenatal ultrasound is an accurate means of identifying the presence of a skeletal dysplasia, however it should be borne in mind that making a specific diagnosis remains difficult. Gaffney and colleagues recently reported a review of 35 cases of skeletal dysplasia diagnosed prenatally. Overall, the suggested prenatal diagnosis was correct in 31 per cent of cases, however the suggested prognosis was correct in 95 per cent.8 In this case, the family history obviously aided in the diagnosis.


References

  1. Mahony BS. Ultrasound Evaluation of the Fetal Musculoskeletal System. In: Ultrasonography in Obstetrics and Gynecology, Third Edition. Callen PW (Ed). W.B> Saunders Company. Philadelphia, PA. 1994. pp 254-290.
  2. Taybi J, Lachman RS. Radiology of Syndromes, Metabolic Disorders, and Skeletal Dysplasias, 3rd ed. Chicago: Year Book Medical Publishers Inc; 1990, 701-703
  3. Spirt BA, Oliphant M, Gottlieb RA, et al. Prenatal sonographic evaluation of short-limbed dwarfism: an algorithmic approach. Radiographics 1990; 10: 217-236.
  4. Buyse ML. Birth Defects Encyclopedia. Center for Birth Defects Information Services, Inc. Dover, MA. 1990, pp. 322.
  5. Mahony BS. The Extremities. In: Diagnostic Ultrasound of Fetal Anomalies, Text and Atlas. Nyberg DA, Mahony BS, Pretorius DH (eds). Year Book Medical Publishers Inc; 1990, pp. 492-562
  6. Horigome H, Hamada H, Sohda S, Oyake Y, Kurosaki Y. Prenatal Ultrasonic Diagnosis of a Case of Ellis-van-Creveld Syndrome with a Single Atrium. Pediatr Radiol 1997; 27(12):942-944.
  7. Digilio MC, Marino B, Giannotti A, Dallapiccola B. Single Atrium, Atrioventricular Canal/Postaxial hexodactyly Indicating Ellis-van Creveld Syndrome. Hum Genet 1995; 96(2): 251-253.
  8. Gaffney G, Manning N, Boyd PA, Rai V, Gould S, Chamberlain P. Prenatal Sonographic Diagnosis of Skeletal Dysplasias-A Report of the Diagnostic and Prognostic Accuracy in 35 Cases. Prenat Diagn 1998; 18(4):357-362.