Inherited polymalformative syndrome characterized by
supernumerary digits, webbing or fusion of digits, large and unusually
shaped skull, frontal bossing, and hypertelorism.
Polysyndactyly with Peculiar Skull Shape;
Polysyndactyly-Dysmorphic Craniofacies, Greig type; Frontodigital Syndrome;
Unknown; more than 100 cases have been described. First
reported in 1926.
There is evidence that this disorder is caused by
a mutation in the zinc finger domain of the GL13 gene (gene map locus 7p13).
There is phenotypic overlap with the Schinzel Acrocallosal syndrome.
Based on clinical findings, family history, and genetic testing.
The range and severity of symptoms is quite variable.
Macroand scaphocephaly, a high forehead with frontal bossing and a broad nasal
root with hypertelorism result in craniofacial dysmorphism, which however
can be subtle in some cases. Although the gene for craniosynostosis is also
located on chromosome 7, craniosynostosis is not a common feature of this disease.
Intelligence is most often normal, but a few cases (less than 10%) have been described
with agenesis of the corpus callosum, seizures and mild mental retardation.
Broad thumbs and halluces, syndactyly (mainly of the fingers 3 and 4 and the toes 1-3),
postaxial polydactyly of the hands, and preaxial polydactyly of the feet are typical.
Hip dislocations have been reported.
Although rare, signs of craniosynostosis
associated with increased intracranial pressure should be ruled out. Cooperation
may be limited in patients with mental retardation and sedative and/or anxiolytic
premedication as well as the presence of the primary caregiver for induction of
anesthesia may be helpful.
Peripheral vascular access may be a bit
more challenging given the anatomical features of the disease. Careful positioning
is recommended to avoid dislocation of the hips. Avoid arterial hypotension, hypoxia,
hypercapnia, and hyperthermia in the presence of increased intracranial pressure (ICP).
Avoid drugs that could result in a further
increase in ICP and avoid premedication in this patient group (risk of hypercapnia and
Schinzel Acrocallosal Syndrome: Polymalformative syndrome
characterized by polydactyly and/or syndactyly, macrocephaly, mental
retardation, ocular hypertelorism, agenesis of the corpus callosum, small
nose and dysplastic ears; mostly sporadic but autosomal recessive forms have
Acrocephalopolysyndactyly Syndromes Type II: Very similar clinical features
but dwarfism is constant and genetic transmission is autosomal recessive.
Pallister-Hall Syndrome: Polymalformative syndrome characterized
by craniofacial anomalies, polydactyly, cardiac and renal malformations,
hypothalamic hamartoblastoma and endocrine disorders, and mild mental
retardation; mostly sporadic but autosomal dominant mutations in chromosomes
3 and 7 have been reported in some cases.
Meckel-Gruber Syndrome: Autosomal recessive lethal
polymalformative syndrome characterized by occipital encephalocele,
polycystic kidneys, polydactyly, and pulmonary hypoplasia (leading cause of
death); mapped to chromosome 17.
Short-Rib Polydactyly Syndrome: Congenital dwarfism with micromelia and
narrowed thorax, polydactyly, and respiratory manifestations; constantly