Prakash C Vaghela, Naresh Gohel, Sonal Mehta
Kalarav Children Hospital, Bhavnagar, India
|Address for Correspondence|
|Dr Prakash C Vaghela, Kalarav children hospital, Kushal neonatal nursery, Akar complex, Opp.Sir T Hospital, Bhavnagar- 364001 , Gujarat, India.|
|1day-Old boy, first in birth order born of 1st degree consanguineous marriage presented with respiratory distress syndrome. He was born at 30weeks, was a breech delivery and had a birth weight of 1.8kg. He cried after 5 minutes of birth. Parents had primary infertility of 8years.
On examination, weight was 1.8kg, length 40cm, and head circumference was 32cm. He had narrow frontal area, low set ears, inner epicanthal fold, broad nasal tip with anteverted nostril, micrognathia, simian crease, and ambiguous genitalia (micropenis, hypospadias, cryptorchidism and rudimentary vagina) and severe respiratory distress. Baby expired within 1 hour due to acute respiratory failure. He was diagnosed to have Smith-Lemli-Opitz syndrome on clinical grounds.
Smith-Lemli-Opitz syndrome (SLOS) is a multiple congenital anomalies/mental retardation (MCA/MR) syndrome. It is a rare autosomal recessive disorder of cholesterol metabolism where in the conversion of 7 dehydrocholesterol (7-DHC) into cholesterol is disrupted leading to excessive accumulations of 7- DHC, 8-DHC and cholesterol deficiency. Mutations in the DHCR7 gene are responsible for SLOS. Spontaneous abortion, congenital heart diseases, death due to multiorgan failure in 1st week, failure to thrive, vomiting, constipation, hearing and visual loss may be present. Diagnosis is based on clinical and biochemical profile like low cholesterol and absent LDL cholesterol, karyotype and Ultrasound abdomen.
Cholesterol replacement forms the cornerstone in medical management and coexisting surgical condition may need appropriate evaluation and intervention.
Prenatal diagnosis by fetal ultrasound may revel multiple congenital anomalies, increased 7-DHC and mutation analysis in amniotic fluid or chorionic venous sampling, decrease maternal serum unconjugated estriol or other marker for triple test with normal karyotype. The unique presence of equine estriols in the maternal urine during pregnancy of a fetus affected by SLOS, potentially allows noninvasive prenatal screening for SLOS.
Last Updated : Tuesday, July 01, 2008 Vol 5 Issue 7 Art #28
- Abuelo DN, Tint GS, Kelley R. Prenatal detection of the cholesterol biosynthetic defect in the Smith- Lemli-Opitz syndrome by the analysis of amniotic fluid sterols. Am J Med Genet 1995 Apr 10; 56(3): 281-5.
- Angle B, Tint GS, Yacoub OA: Atypical case of Smith-Lemli-Opitz syndrome: implications for diagnosis. Am J Med Genet 1998 Dec 4; 80(4): 322-6.
- Battaile KP, Maslen CL, Wassif CA, Krakowiak P, Porter FD, Steiner RD: A simple PCR-based assay allows detection of a common mutation, IVS8-1G- ->C, in DHCR7 in Smith-Lemli-Opitz syndrome. Genet Test 1999; 3(4): 361-3.
- Battaile KP, Steiner RD: Smith-Lemli-Opitz syndrome: the first malformation syndrome associated with defective cholesterol synthesis. Mol Genet Metab 2000 Sep-Oct; 71(1-2): 154-62.
- Bradley LA, Palomaki GE, Knight GJ. Levels of unconjugated estriol and other maternal serum markers in pregnancies with Smith-Lemli-Opitz (RSH) syndrome fetuses. Am J Med Genet 1999 Feb 12; 82(4): 355-8.
- Bronshtein M, Riechler A, Zimmer EZ: Prenatal sonographic signs of possible fetal genital anomalies. Prenat Diagn 1995 Mar; 15(3): 215-9.
- Canick JA, Abuelo DN, Bradley LA: Maternal serum marker levels in two pregnancies affected with Smith- Lemli-Opitz syndrome. Prenat Diagn 1997 Feb; 17(2): 187-9.
- Dallaire L, Mitchell G, Giguere R. Prenatal diagnosis of Smith-Lemli-Opitz syndrome is possible by measurement of 7-dehydrocholesterol in amniotic fluid. Prenat Diagn 1995 Sep; 15(9): 855-8.
- Elias ER, Irons MB, Hurley AD: Clinical effects of cholesterol supplementation in six patients with the Smith-Lemli-Opitz syndrome (SLOS). Am J Med Genet 1997 Jan 31; 68(3): 305-10.
- Ginat S, Maslen CL, Connor WE. Smith-Lemli-Opitz syndrome: a multiple malformation/mental retardation syndrome caused by defective cholesterol synthesis. The Endocrinologist 2000; 10: 300-314.
|How to Cite URL :|
|Vaghela C P, Gohel N, Mehta S. SMITH - LEMLI OPITZ SYNDROME. Pediatric Oncall [serial online] 2008[cited 2008 January 1];5. Art #28. Available From : http://www.pediatriconcall.com/Journal/Article/FullText.aspx?artid=105&type=J&tid=&imgid=&reportid=305&tbltype=|