Inherited syndrome with marfanoid features and
X-linked mental retardation.
X-Linked Mental Retardation with Marfanoid Habitus
Approximately 59 cases reported up to 2005, almost
exclusively in males.
X-linked dominant transmission with a greater
expressivity and penetrance in males has been suggested.
Major criteria include mild-to-moderate mental
retardation; marfanoid habitus; generalized hypotonia; hypernasal voice;
normal secondary sexual development and normal or enlarged testicular size;
characteristic craniofacial appearance with large forehead; contrasting long
and narrow face; maxillary hypoplasia; long nose with high and narrow nasal
bridge; short and deep philtrum; thin upper lip; and high-arched palate.
Patients appear tall and slender with long limbs
and fingers (arachnodactyly). General muscular hypotonia and hyperlaxity of
the joints are further features. Seizures are possible, and mental
retardation is described as mild to severe. Partial or complete agenesis of
the corpus callosum has been reported in some cases. A high forehead and a
long, narrow face with hypoplastic mandible and micrognathia with a narrow
and high-arched palate are typical. The nasal bridge is high, and the ears
are low set and posteriorly rotated. Kyphoscoliosis and pectus excavatum are
present in some cases. Cardiac defects (atrial septal defect) have been
described, and two (related) patients were reported to have dilatation of
the aortic root and a ventricular septa defect.
Depending on the severity of
kyphoscoliosis, restrictive lung disease and cor pulmonale may be present.
If kyphoscoliosis is significant, pulmonary investigations should include a
chest radiograph, arterial blood gas analysis, and lung function tests
(although they may be difficult to obtain in a mentally delayed patient).
Preoperative assessment should include echocardiography to rule out
congenital heart defects and to determine the size of the aortic root.
Finally, the association of a hypoplastic mandible and micrognathia should
prompt complete evaluation of the airway.
No reports referring to anesthesia were
found. However, airway management could be challenging in the presence of
the aforementioned facial anomalies. Therefore, proper preparation for
difficult direct laryngoscopy and tracheal intubation should be planned.
Patient compliance is likely to increase with sedative and anxiolytic
premedication given that psychotic, autistic-like, and aggressive behavior
have been reported.
Some patients are taking antiseizure
medication. These drugs can induce hepatic enzymes, thereby altering the
metabolism of other drugs with predominant hepatic clearance. Because of
aortic root dilatation, these patients may also be on beta-blocker therapy.
De Die-Smulders Vles Fryns Syndrome: Genetic disorder
characterized by a characteristic facies, marfanoid habitus, and mental
Marfan Syndrome: Autosomal dominant connective-tissue disorder
linked to the FBN1 gene on chromosome 15 that encodes fibrillin 1. Without
fibrillin, many tissues are weakened, especially the joints, tendons, lens,
and walls of major arteries. Aortic regurgitation and dissection are
responsible for premature death in the third to fifth decade.
Congenital Contractural Arachnodactyly: Marfan-like appearance,
“crumpled” ears, contractures of major joints, ...