Prenatal Presentation and Diagnostic Evaluation of Suspected Smith–Lemli–Opitz (RSH) Syndrome
Article first published online: 26 MAR 2013
Copyright © 2013 Wiley Periodicals, Inc.
American Journal of Medical Genetics Part A
Volume 161, Issue 5, pages 1008–1011, May 2013
How to Cite
2013. Prenatal presentation and diagnostic evaluation of suspected Smith–Lemli–Opitz (RSH) syndrome. Am J Med Genet Part A 161A:1008–1011., , , .
- Issue published online: 22 APR 2013
- Article first published online: 26 MAR 2013
- Manuscript Accepted: 10 DEC 2012
- Manuscript Received: 12 NOV 2012
- Smith–Lemli–Opitz syndrome;
- antenatal manifestations;
- sterol analysis;
- amniotic fluid;
- prenatal diagnosis
Smith–Lemli–Opitz (SLOS), or RSH syndrome, is an autosomal recessive deficiency of 7-dehydrocholesterol reductase (DHCR7) resulting in an accumulation of 7- and 8-dehydrocholesterol (7- and 8-DHC) in tissues and body fluids. At birth patients have variable malformations of CNS, heart, kidney, genitalia, and limbs, which may be life-limiting. In later course, psychomotor and mental retardation and behavior abnormalities become evident. Prenatally SLOS can be suspected on the basis of malformations and intrauterine growth retardation (IUGR) in prenatal ultrasonography and reduced maternal free estriol in serum. The diagnosis is confirmed by sterol analysis in a chorionic villus biopsy or amniotic fluid (AF). In this study, we evaluated the predictive value of the above mentioned criteria in combination with family history by quantification of sterols in AF in pregnancies with either a family history, ultrasonographical abnormalities typical for SLOS, or reduced maternal serum unconjugated estriol (MSuE3). The relative frequency of SLOS in fetuses with an affected sibling was 0.23, as to be expected for an autosomal recessive disease. The probability for SLOS was <0.6% when neither an affected sib nor more than one typical SLOS malformation was present. For safety reasons and for cost-effectiveness we recommend careful evaluation of history, MSuE3, and clinical presentation before determining sterols in AF. © 2013 Wiley Periodicals, Inc.