A sporadic disorder characterized by radial limb defects as well as anomalies of the prosencephalic structures, aprosencephaly, atelencephaly, and microcephaly in association with congenital heart defects (ventricular and atrial septal defects, patent ductus arteriosus, coarctation of the aorta), preaxial limb malformations, eye (cyclopia), and genital abnormalities. Micrognathia and craniofacial disproportion characterized this condition.
Aprosencephaly Syndrome; Aprosencephaly-Atelencephaly Syndrome; XK Syndrome; XK-Aprosencephaly Syndrome; Garcia-Lurie-Steinfeld Syndrome.
Aprosencephaly is a lethal malformation of the central nervous system.
Very rare malformation of unknown incidence.
Autosomal recessive inheritance suggested. Chromosome 13 has been implicated, with suspicion of a deletion of the long arm of chromosome 13.
Aprosencephaly has been attributed to a postneurulation encephaloclastic process. Cause of Aprosencephaly Syndrome is unknown.
Diagnosis of a severe brain malformation can already be made antenatally by ultrasonography. Reported cases describe autopsy finding in fetuses and postnatally dead infants.
Aprosencephaly is characterized by a midline oculofacial defect in association with limb and genital anomalies. Anencephaly has been described. Other findings include congenital heart defects (ventricular and atrial septal defects, patent ductus arteriosus, coarctation of the aorta), preaxial limb malformations (humerus-radial fusion, hip dislocation), eye (cyclopia, hypertelorism), and genital abnormalities. Furthermore, micrognathia and craniofacial disproportion, high arched palate, and adrenal hypoplasia have also been described.
Precautions before anesthesia
Complete evaluation of all systems is mandatory, especially cardiac and pulmonary. Adrenal function should be evaluated and corticosteroid supplementation considered, if necessary. Laboratory reports must include electrolytes, acid-base status, coagulation profile, renal function, and complete blood count (CBC).
Difficult direct laryngoscopy and tracheal intubation should be expected. The presence of congenital heart defects must be considered in the preparation of the anesthetic. Cortisol supplement may be necessary in the presence of adrenal insufficiency.
Indicated by the complexity of the associated conditions. Subacute bacterial endocarditis prophylaxis may be required. No specific known implications with this condition.
Other condition to be considered
Steinfeld Syndrome: Steinfeld Syndrome is an extremely variable autosomal dominant condition that, in severe cases, is characterized by holoprosencephaly, radial limb defects, and renal and/or cardiac defects. This is also reported in the Garcia Lurie Syndrome (XK aprosencephaly) and partial monosomy 13q. In milder cases there may be only thumb hypoplasia, ocular coloboma, or oral clefts. Based on two atypical sibships, autosomal recessive inheritance has been suggested.
EG: Sporadic case of apparent aprosencephaly. Am J Med Genet