Metaphyseal chondrodysplasia Jansen type
Classification according to ICD-10 | |
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Q78.5 | Metaphyseal dysplasia |
ICD-10 online (WHO version 2019) |
The Jansen metaphyseal chondrodysplasia is a congenital skeletal dysplasia with marked changes in the growing bone located in the metaphyses .
Synonyms are:
- Jansen's syndrome
- Murk-Jansen syndrome
- Dysostosis metaphysaria Murk Jansen
The name refers to the author of the first description from 1934, the Dutch orthopedic surgeon Murk Jansen (1863-1935).
distribution
The frequency is given as less than 1 in 1,000,000, inheritance is autosomal dominant .
root cause
The disease is based on various mutations in the PTHR1 gene at the 3p21.31 location. This gene codes for the PTH / PTHrP receptor. The PTHR1 protein mediates the PTH-dependent regulation of calcium and phosphate in the kidneys and bones. The gene is also expressed in the bone growth plate.
Clinical manifestations
Diagnostic criteria are:
- Skeletal changes similar to rickets after birth
- Disproportionate short stature with bending of the forearms and lower legs, distended joints, ligament laxity, thoracic deformity , adult height is 100–150 cm
- Micrognathy
- prominent supraorbital bulge in adults
diagnosis
The X-ray image documents a osteopenia , cup-shaped swollen, later appearing fragmented metaphyseal and wide growth plates , at normal epiphysis .
Differential diagnosis
In the differential diagnosis, there is a risk of confusion with rickets and hyperparathyroidism .
literature
- K. Nolte, G. Schiebe: Radiological diagnosis (and differential diagnosis) of the lethal (congenital) type of hypophosphatasia. In: The Radiologist. Vol. 16, No. 7, July 1976, pp. 283-285, ISSN 0033-832X . PMID 959514 .
- K. Kozlowski, JB Campbell, ME Azouz, P. Sprague: Metaphyseal chondrodysplasia, type Jansen. In: Australasian radiology. Vol. 43, No. 4, November 1999, pp. 544-547, ISSN 0004-8461 . PMID 10901979 .
Individual evidence
- ↑ a b c B. Leiber: The clinical syndromes. Syndromes, sequences and symptom complexes. Edited by G. Burg, J. Kunze, D. Pongratz, PG Scheurlen, A. Schinzel, J. Spranger, 7th edition. Urban & Schwarzenberg 1990, ISBN 3-541-01727-9
- ↑ M. Jansen: About atypical chondrodystrophy (achondroplasia) and about a not yet described congenital growth disorder of the bone system: metaphyseal dysostosis. In: Zeitschrift für Orthopädie und Chirurgie 1934, Vol. 61, pp. 253-286.
- ↑ a b Jansen's metaphyseal chondrodysplasia. In: Orphanet (Rare Disease Database).