A lethal form of mesomelic dwarfism associated with
severe multiple cardiac, respiratory, and skeletal malformations. It is also
known as the polydactyly, sex reversal, renal hypoplasia, and unilobular
Smith-Lemli-Opitz Syndrome type II; Lethal
Acro-Dysgenital Syndrome; Lethal Multiple Congenital Anomaly Syndrome.
First described by J.C. Rutledge in 1984.
Autosomal recessive; allelic to
Smith-Lemli-Opitz syndrome type I.
Possible primary fetal adrenal defect, resulting
in multiple congenital abnormalities. May be linked to mutations in
delta-7-dehydrocholesterol reductase; gene located at 11q12-q13.
Clinical features (mesomelic dwarfism, micrognathia,
V-shaped upper lip, ambiguous genitalia, clubfeet, fused fontanelles,
inclusion cysts of the tongue, widely spaced nipples, and digital
anomalies). Prenatal diagnosis by ultrasonography and analysis of
cholesterol level from amniocentesis is possible.
Features include mesomelic dwarfism,
craniofacial deformations (fused fontanelles, low-set ears, micrognathia, V-shaped upper lip, thick
alveolar ridges, high-arched palate or cleft palate, abnormal tongue,
cataract), cardiac and respiratory malformations (severe congenital heart defect, pulmonary
hypoplasia, unilobar lungs, laryngeal hypoplasia), genitourinary signs
(ambiguous genitalia, oligopapillary, renal hypoplasia), gastrointestinal
(gallbladder hypoplasia, pancreatic islet cell hyperplasia, megacolon), and orthopedic malformations (polydactyly, syndactyly, clubfoot, joint contractures).
Cerebellar hypoplasia is associated. Affected patients usually die within a few hours
or days of birth.
Complete examination and full
assessment of cardiac, respiratory, and renal function (clinical,
radiographs, echography, arterial blood gas analysis). Complete biochemistry
evaluation should be obtained. Volemia should be assessed because of renal
anomalies. Because of the possibility of laryngeal hypoplasia, proper
evaluation must be sought.
No reported experience because of the
rarity and very early lethality of the syndrome. Direct laryngoscopy and tracheal
intubation could probably be difficult because of facial anomalies.
Postoperative ventilatory support may be necessary.
Perioperative fluid regimen and drugs
doses should be adapted to renal function. Cardiac prophylactic antibiotics
Curry CJR, Carey JC, Holland JS, et al: Smith-Lemli-Opitz syndrome-type
II: Multiple congenital anomalies with male pseudohermaphroditism and
frequent early lethality. Am J Med Genet
Rutledge JC, Friedman JM, Harrod MJE, et al: A “new” lethal multiple
congenital anomaly syndrome: Joint contractures, cerebellar hypoplasia,
renal hypoplasia, urogenital anomalies, tongue cysts, shortness of limbs,
eye abnormalities, defects of the heart, gallbladder agenesis, and ear
malformations. Am J Med Genet