Geleophysic dysplasia
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(Spanger's gelophysic dwarfism)
Prevalence: 1.106. Form of dwarfism.
There are three types:
- type 1 [MIM 231 050]: autosomal recessive transmission of a mutation of the ADAMTSL2 gene (9q34.2) coding for the Disintegrin And Metalloproteinase with Thrombospondin repeats- like 2 glycoprotein
- type 2 [MIM 614 185]: autosomal dominant transmission of a mutation of the FBN1 gene (15q21.1) coding for fibrillin 1; this form is allelic with acromicric dysplasia and the autosomal dominant form of Weill-Marchesani syndrome (see these terms).
- type 3 [MIM 617 809]: autosomal recessive transmission of a mutation of the LTBP3 gene (11q13).
These mutations would lead to a disorganization of the microfibrillary network and an increase in the signal of the TGF-β .
Clinical features:
- characteristic facies (happy face): short nose, round cheeks, hypertelorism, long and flat philtrum and thin upper lips.
- gradual thickening of the cardiac valves (aortic, mitral, pulmonary) often resulting in early death
- contraction of the gastrocnemius muscle and the Achilles tendon producing tiptoe walking,
- tracheal stenosis, which can lead to respiratory failure
- hepatomegaly due to the accumulation of heparan-sulfate
- at the bone level: bone age delay, conical epiphyses, short tubular bones (especially in the hands and feet) and ovoid vertebral bodies.
Anesthetic implications:
echocardiography; short stature; endotracheal tube size ? increased risk of tracheal stenosis; difficult peripheral venous access.
References :
- Allali S, Le Goff C, Pressac-Diebold I, Pfennig G, Mahaut C et al.
Molecular screening of ADAMTSL2 gene in 33 patients reveals the genetic heterogeneity of geleophysic dysplasia.
J Med Genet 2011; 48: 417-21.
Updated: March 2020