Pseudoachondroplasia: clinical diagnosis at different ages and comparison of autosomal dominant and recessive types. A review of 32 patients (26 kindreds).

This survey reviews the diagnosis (predominantly radiological) of 32 cases of pseudoachondroplasia from 26 kindreds and illustrates the natural history and varying appearance of the disordered bone growth from infancy to adult life. In addition, an attempt has been made to detect phenotypic differences between autosomal dominant and recessive types (excluding isolated cases), analysing 10 kindreds of dominant inheritance (three in the current survey, seven from published reports) and six of recessive inheritance (three in the current survey, three from published reports). There appears to be no clinical or radiographical feature which clearly distinguishes them, but, using height as a criterion of severity, among those with autosomal recessive inheritance there was a disproportionate number of the most severely affected cases and there also appears to be very little intrafamilial variation. It is possible that pseudoachondroplasia can be subdivided into autosomal dominant mild and severe and autosomal recessive mild and severe, but full delineation must await elucidation of the basic defect at biochemical and molecular levels.