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1999-05-23-21 Mesomelic dysplasia © Jeanty www.thefetus.net/


Mesomelic dysplasia 

Philippe Jeanty, MD, PhD & Sandra R Silva, MD

Definition: As implied by its name, mesomelic dysplasia is a skeletal disorder with anomalies of the ulna-radius and tibia-fibula. These anomalies are predominantly hypoplasia and shortening but these bones can also be malformed or fused. A large number of associated anomalies exist such as hypoplasia of the mandible, ulnar deviation of hands, talipes equinovarus, distal tapering of the humeri, and hypoplastic fibulae, radii, and ulnae[1], bony spurs of the diaphyses[2], carpal/tarsal synostosis, and dorsolateral foot deviation8,[3]. The most typical form (Langer type) is considered to be the homozygote form of the Leri-Weill Dyschondrosteosis[4].

Synonyms: Langer Type Mesomelic Dwarfism; Dyschondrosteosis, Homozygous.

Incidence: Rare.

Etiology: Autosomal-recessive inheritance.

Recurrence risk: 25%.

Diagnosis: The mesomelic findings have been recognized as early as the first trimester in an at-risk propositus[5] and in a routine exam in the second trimester[6],[7].

Pathogenesis: Nonsense mutation of the gene for the short stature homeobox (SHOX), which is involved in idiopathic growth retardation and possibly Turner short stature9.

Genetic anomaly: The gene for one form of mesomelic dysplasia (the Kantaputra type3) is mapped to chromosome 2q24-q32[8]. The Leri-Weill Dyschondrosteosis has been linked to the marker DXYS6814 in the pseudoautosomal region (PAR1) of the X and Y chromosomes (more severe in females)4, and to the DCS gene to a microsatellite DNA marker at the DXYS233 locus[9].

Associated anomalies: See definition. Aside from the mesomelic dysplasia most other anomalies are skeletal and the most striking is micrognathia.

Differential diagnosis: Many other skeletal dysplasias present with mesomelic anomalies and these would include chondrodysplasia punctata (look for stippled calcifications in the sacrum)[10], brachymesomelia[11] and chondroectodermal dysplasia [12] among many.

Prognosis: Disproportionate short stature. Some forms have normal intellectual capacity.

Management: When recognized prenatally, termination of pregnancy can be offered.

References:


[1] Brodie SG, Lachman RS, Crandall BF, Fox MA, Rimoin DL, Cohn DH, Wilcox WR: Radiographic and morphologic findings in a previously undescribed type of mesomelic dysplasia resembling atelosteogenesis type II. Am J Med Genet 1998 Nov 16;80(3):247-51

[2] Kerner B, Rimoin DL, Lachman RS: Mesomelic shortening of the upper extremities with spur formation and cutaneous dimpling. Pediatr Radiol 1998 Oct;28(10):794-7

[3] Kantaputra PN, Gorlin RJ, Langer LO Jr Dominant mesomelic dysplasia, ankle, carpal, and tarsal synostosis type: a new autosomal dominant bone disorder. Am J Med Genet 1992 Dec 1;44(6):730-7

[4] Shears DJ, Vassal HJ, Goodman FR, Palmer RW, Reardon W, Superti-Furga A, Scambler PJ, Winter RM: Mutation and deletion of the pseudoautosomal gene SHOX cause Leri-Weill dyschondrosteosis. Nat Genet 1998 May;19(1):70-3

[5] den Hollander NS, van der Harten HJ, Vermeij-Keers C, Niermeijer MF, Wladimiroff JW: First-trimester diagnosis of Blomstrand lethal osteochondrodysplasia. Am J Med Genet 1997 Dec 19;73(3):345-50

[6] Roth P, Agnani G, Arbez-Gindre F, Maillet R, Colette C: Langer mesomelic dwarfism: ultrasonographic diagnosis of two cases in early mid-trimester. Prenat Diagn 1996 Mar;16(3):247-51

[7] Evans, M. I, Zador, I. E, Qureshi, F, Budev, H, Quigg, M. H, Nadler, H. L. : Ultrasonographic prenatal diagnosis and fetal pathology of Langer mesomelic dwarfism. Am. J. Med. Genet. 31: 915-920, 1988.

[8] Fujimoto M, Kantaputra PN, Ikegawa S, Fukushima Y, Sonta S, Matsuo M, Ishida T, Matsumoto T, Kondo S, Tomita H, Deng HX, D"urso M, Rinaldi MM, Ventruto V, Takagi T, Nakamura Y, Niikawa N: The gene for mesomelic dysplasia Kantaputra type is mapped to chromosome 2q24-q32.  J Hum Genet 1998;43(1):32-6

[9] Belin V, Cusin V, Viot G, Girlich D, Toutain A, Moncla A, Vekemans M, Le Merrer M, Munnich A, Cormier-Daire V: SHOX mutations in dyschondrosteosis (Leri-Weill syndrome). Nat Genet 1998 May;19(1):67-9

[10] Argo KM, Toriello HV, Jelsema RD, Zuidema LJ: Prenatal findings in chondrodysplasia punctata, tibia-metacarpal type. Ultrasound Obstet Gynecol 1996 Nov;8(5):350-4

[11] Kivlin JD, Carey JC, Richey MA: Brachymesomelia and Peters anomaly: a new syndrome. Am J Med Genet 1993 Feb 15;45(4):416-9

[12] Qureshi F, Jacques SM, Evans MI, Johnson MP, Isada NB, Yang SS: Skeletal histopathology in fetuses with chondroectodermal dysplasia (Ellis-van Creveld syndrome). Am J Med Genet 1993 Feb 15;45(4):471-6

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