Differential Diagnosis
SOST-related sclerosing bone dysplasias must be distinguished from other sclerosing bone dysplasias, including: • The osteoscleroses, notably osteopetrosis, characterized by increased bone density with no bone overgrowth and little or no disturbance of the contours of the bones; • The craniotubular dysplasias, characterized by abnormal modeling of the skeleton and moderate sclerosis of the calvarium and base of the skull. The predominant feature of the craniotubular hyperostoses is overgrowth of bone, which leads to alterations of contours and increase in radiologic density of the skeleton. The bones are often very resistant to trauma. In addition to SOST-related sclerosing bone dysplasias, this group of disorders includes the conditions summarized in . Table 3. Other Craniotubular Hyperostoses to Consider in the Differential Diagnosis of SOST-Related Sclerosing Bone Dysplasias
Gene | Disorder | MOI | Features of Disorder |
|---|
LRP4 | LRP4-related sclerosteosis (OMIM 614305) | ADAR | Hyperostosis of long bones skull; Facial deformity; Cranial nerve impingement hearing loss; Tall stature |
LRP5 | Endosteal hyperostosis, Worth type (OMIM 144750) | AD | Hyperostosis of long bones skull; Cranial nerve impingement hearing loss; Enlargement of mandible |
No syndactyly SOST1 | SOST-related craniodiaphyseal dysplasia | AD | Hyperostosis of skull; Facial deformity w/hypertelorism; Cranial nerve impingement hearing loss |
No syndactyly SP72 | SP7-related craniodiaphyseal dysplasia | AR | Facial dysmorphism; Severe hyperostosis of calvarium, skull base, mandible |
1 of 2 persons reported had recurrent fractures. TGFB13 | TGFB1-related Camurati-Engelmann diaphyseal dysplasia (See Camurati-Engelmann Disease.) | AD | Hyperostosis of long bones; Frontal bossing, enlargement of mandible, proptosis, cranial nerve impingement later in life in those w/severe disease |
Source: GeneReviews — "SOST-Related Sclerosing Bone Dysplasias"
