1/181. Unusual fan shaped ossification in a female fetus with radiological features of boomerang dysplasia.We report on a female fetus of 24 weeks whose clinical and radiological findings were compatible with boomerang dysplasia (BD). However, histopathology was unusual with a lateral fan shaped diaphyseal ossification. This has never been described either in typical atelosteogenesis I (AT-I) or in BD. The purpose of this report is to find out if this condition is a separate lethal bone dysplasia or another histological feature of the nosological group of AT-I and BD.- - - - - - - - - - ranking = 1keywords = diaphyseal (Clic here for more details about this article) |
2/181. Metaphyseal anadysplasia in two sisters.Metaphyseal anadysplasia is a rare form of metaphyseal chondrodysplasia with well-defined radiological abnormalities. The prognosis is good as the natural course results in regression of the lesions with normal stature in adulthood. The few reported cases, exclusively in male children, indicated possible X-linked recessive transmission. The documentation of two affected sisters suggests genetic heterogeneity or another mode of inheritance.- - - - - - - - - - ranking = 124.32719706316keywords = chondrodysplasia (Clic here for more details about this article) |
3/181. Congenital hypertrichosis, osteochondrodysplasia, and cardiomegaly: Cantu syndrome.Cantu syndrome (hypertrichosis, osteochondrodysplasia, cardiomegaly) is a rare condition, previously reported in 13 patients. We report on two additional patients with this disorder. One of the patients had pulmonary hypertension of unknown cause which was responsive to steroid therapy. She also had unusual, deep plantar creases, not reported previously in Cantu syndrome. Autosomal recessive inheritance has been suggested previously on the basis of sib recurrence in one family and consanguinity in another. We have performed a segregation analysis based on all reported families to date; the data indicate autosomal recessive inheritance is unlikely. A new dominant mutation or microdeletion syndrome are more likely possibilities, sib recurrence possibly representing gonadal mosaicism.- - - - - - - - - - ranking = 621.63598531579keywords = chondrodysplasia (Clic here for more details about this article) |
4/181. Homozygosity for a novel DTDST mutation in a child with a 'broad bone-platyspondylic' variant of diastrophic dysplasia.Atypical or variant forms of well-known chondrodysplasias may pose diagnostic problems. We report on a girl with clinical features suggesting diastrophic dysplasia but with unusual radiographic features including severe platyspondyly, wide metaphyses, and fibular overgrowth, which are partially reminiscent of metatropic dysplasia. The diagnosis was clarified by molecular analysis of the DTDST gene, which revealed homozygosity for a previously undescribed mutation leading to a Q454P substitution in the 10th transmembrane domain of the DTDST sulfate transporter. Molecular analysis may be of particular value in such atypical cases.- - - - - - - - - - ranking = 124.32719706316keywords = chondrodysplasia (Clic here for more details about this article) |
5/181. A novel parathyroid hormone (PTH)/PTH-related peptide receptor mutation in Jansen's metaphyseal chondrodysplasia.Two heterozygous PTH/PTH-related peptide (PTHrP) receptor missense mutations were previously identified in patients with Jansen's metaphyseal chondrodysplasia (JMC), a rare form of short limb dwarfism associated with hypercalcemia and normal or undetectable levels of PTH and PTHrP. Both mutations, H223R and T410P, resulted in constitutive activation of the cAMP signaling pathway and provided a plausible explanation for the abnormalities in skeletal development and mineral ion homeostasis. In the present study we analyzed genomic dna from four additional sporadic cases with JMC to search for novel activating mutations in the PTH/PTHrP receptor, to determine the frequency of the two previously identified missense mutations, H223R and T410P, and to determine whether different mutations present with different severity of the disease. The H223R mutation was identified in three novel JMC patients and is, therefore, to date the most frequent cause of JMC. In the fourth patient, a novel heterozygous missense mutation was found that changes isoleucine 458 in the receptor's seventh membrane-spanning region to arginine (I458R). In COS-7 cells expressing the human PTH/PTHrP receptor with the I458R mutation, basal cAMP accumulation was approximately 8 times higher than that in cells expressing the wild-type receptor despite impaired surface expression of the mutant receptor. Furthermore, the I458R mutant showed higher responsiveness to PTH than the wild-type receptor in its ability to activate both downstream effectors, adenylyl cyclase and phospholipase C. Like the H223R and the T410P mutants, the I458R mutant had no detectable effect on basal inositol phosphate accumulation. overall, the patient with the I458R mutation exhibited clinical and biochemical abnormalities similar to those in patients with the previously identified H223R and T410P mutations.- - - - - - - - - - ranking = 621.63598531579keywords = chondrodysplasia (Clic here for more details about this article) |
6/181. A frame-shift mutation in the type I parathyroid hormone (PTH)/PTH-related peptide receptor causing Blomstrand lethal osteochondrodysplasia.Blomstrand osteochondrodysplasia (BOCD) is a rare lethal skeletal dysplasia characterized by accelerated endochondral and intramembranous ossification. Comparison of the characteristics of BOCD with type I PTH/PTH-related peptide (PTHrP) receptor-ablated mice reveals striking similarities that are most prominent in the growth plate. In both cases, the growth plate is reduced in size due to a strongly diminished zone of resting cartilage and the near absence of columnar arrangement of proliferating chondrocytes. This overall similarity suggested that an inactivating mutation of the PTH/PTHrP receptor might be the underlying genetic defect causing BOCD. Indeed, inactivating mutations of the PTH/PTHrP receptor have been recently identified in two cases of BOCD. We describe here a novel inactivating mutation in the PTH/PTHrP receptor. sequence analysis of all coding exons of the type I PTH/ PTHrP receptor gene and complementary dna of a case with BOCD identified a homozygous point mutation in exon EL2 in which one nucleotide (G at position 1122) was absent. The mutation was inherited from both parents, supporting the autosomal recessive nature of the disease. The missense mutation resulted in a shift in the open reading frame, leading to a truncated protein that completely diverged from the wild-type sequence after amino acid 364. The mutant receptor, therefore, lacked transmembrane domains 5, 6, and 7; the connecting intra- and extracellular loops; and the cytoplasmic tail. Functional analysis of the mutant receptor in COS-7 cells and of dermal fibroblasts obtained from the case proved that the mutation was indeed inactivating. Neither the transiently transfected COS-7 cells nor the dermal fibroblasts responded to a challenge with PTH or PTHrP with a rise in intracellular cAMP levels, in sharp contrast to control cells. Our results provide further evidence that BOCD is caused by inactivating mutations of the type I PTH/PTHrP receptor and underscore the importance of this receptor in mammalian skeletal development.- - - - - - - - - - ranking = 621.63598531579keywords = chondrodysplasia (Clic here for more details about this article) |
7/181. Schimke immuno-osseous dysplasia: case report and review of 25 patients.Immuno-osseous dysplasia is characterised by spondyloepiphyseal dysplasia, lymphopenia with defective cellular immunity, and progressive renal disease. We describe a patient with a severe form of the disease, review the features of another 24 patients, and discuss the previous classification. The differences between the two groups are not striking, and although similarities are greater between affected sibs, the same diagnosis of Schimke immuno-osseous dysplasia should apply to them all. The aetiology and physiopathology of this rare osteochondrodysplasia of presumed autosomal recessive inheritance remain unknown.- - - - - - - - - - ranking = 124.32719706316keywords = chondrodysplasia (Clic here for more details about this article) |
8/181. Blomstrand chondrodysplasia: a lethal sclerosing skeletal dysplasia. Case report and review.We report a female stillborn with typical clinical, radiological, and anatomopathological features of Blomstrand chondrodysplasia. The main findings in this lethal osteochondrodysplasia are osteosclerosis and advanced skeletal maturation. Autosomal recessive inheritance has been proposed because of parental consanguinity of affected siblings in all reported cases, including this one. Histopathological study of the bones confirmed the advanced skeletal maturation radiological features. We also review this rare lethal osteochondrodysplasia.- - - - - - - - - - ranking = 870.29037944211keywords = chondrodysplasia (Clic here for more details about this article) |
9/181. Pathological fractures in spondyloenchondrodysplasia: case report.We present a patient with spondyloenchondrodysplasia who sustained two pathological fractures of long bones in a period of 6 months. This complication of spondyloenchondrodysplasia has not been described previously. Since both fractures occurred with mild trauma, it would appear that spondyloenchondrodysplasia can be associated with a tendency towards pathological fractures and, therefore, it would be advisable to warn people suffering from this condition to avoid activities that put excessive strain on the limbs.- - - - - - - - - - ranking = 870.29037944211keywords = chondrodysplasia (Clic here for more details about this article) |
10/181. Blomstrand osteochondrodysplasia: three novel cases and histological evidence for heterogeneity.Blomstrand osteochondrodysplasia (BOCD) is a rare, autosomal recessive, lethal skeletal dysplasia characterized by generalized osteosclerosis and advanced skeletal maturation. The histopathological characteristics of three novel cases (two isolated cases and a sib-pair) of BOCD are presented and correlated with the clinical and radiographical findings, and the relevant literature is reviewed. The results of our study confirm the existence of two separate types of BOCD, which we propose naming type I: the severe, 'classical' form, and type II: a less severe form.- - - - - - - - - - ranking = 621.63598531579keywords = chondrodysplasia (Clic here for more details about this article) |
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