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R S Lachman

Publications and source records attributed to R S Lachman.

At least 55 records · Page 3Linked to original sources
PubMed1998

Extra pelvic ossification centers in thanatophoric dysplasia and platyspondylic lethal skeletal dysplasia-San Diego type.

The platyspondylic lethal skeletal dysplasias (PLSD) are a group of heterogeneous disorders including thanatophoric dysplasia (TD) and the TD variants (San Diego, Torrance, and Luton types). TD is the most common form and has been divided into two subtypes (TD1 and TD2) based on clinical and radiologic criteria and analysis of mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. The variants are distinguished from TD by characteristic radiographic and chondro-osseous morphologic features. We have recently identified FGFR3 mutations in PLSD-San Diego type (PLSD-SD) which are identical to those found in TD1, but the known TD FGFR3 mutations were not found in the other PLSD variants. After reviewing radiographs from 32 cases of PLSD-SD and 47 cases of TD with gestational ages under 24 weeks, we noted novel accessory ossification centers in the ischia of 18 cases of PLSD-SD and 44 of TD, and the ilia in 18 cases of PLSD-SD and 20 of TD. Only three cases of TD and five cases of PLSD-SD did not have extra pelvic ossification centers. At a gestational age greater than 24 weeks, the extra centers are fused with the main bone. The radiographic appearance and chondro-osseous morphology of cases with and without accessory pelvic ossification centers were otherwise indistinguishable. Morphologically, the accessory pelvic ossification centers resulted from membranous ossification. Extra pelvic ossifications are a common radiographic finding in TD and PLSD-SD.

Abnormalities, Multiple↗
PubMed1998

Coronal and sagittal clefts in skeletal dysplasias.

Objective. To assess the role of coronal and sagittal vertebral clefts in diagnosing skeletal dysplasias. Material and Methods. A search in the database at the International Skeletal Dysplasia Registry revealed 40 different diagnoses in which coronal or sagittal clefts were present, the major groups being: atelosteogenesis, chondrodysplasia punctata, dyssegmental dysplasia, Kniest dysplasia and short rib polydactyly syndrome. We reviewed all firm cases with both AP and lateral films of the spine in these major groups (n = 143), with patients' ages ranging from 20 weeks of gestation up to 26 years of age. Results. Ninety-four percent of all clefts were found in children less than 1 year of age, mainly located in the thoracolumbar region. Fifty-six percent of the clefts were observed in boys. Coronal clefts were more common than sagittal clefts. Clefts were most frequently observed in atelosteogenesis (88%), followed by chondrodysplasia punctata (79%), dyssegmental dysplasia (73%), Kniest dysplasia (63%) and short rib polydactyly syndrome (53%). Conclusion. Vertebral clefts are of major diagnostic value in the groups mentioned above, especially before 1 year of age. The search did not come up with new entities in which vertebral clefts are of major diagnostic value.

Adolescent↗
PubMed1998

Mesomelic shortening of the upper extremities with spur formation and cutaneous dimpling.

We report a boy with mesomelic dysplasia of the forearms, skin dimples, mildly bowed tibiae, metatarsus adductus, congenital cataracts, sensorineural hearing loss, hypotonia, and mildly dysmorphic features. Prominent radiologic findings include bony spurs of the diaphyses of the radii bilaterally with angulated, significantly shortened radii and ulnae and elbow dislocations. Changes in the lower extremities are confined to bowing of the tibiae and elongation of the thinned fibulae. To our knowledge this case represents a unique combination of findings not previously reported, although some resemblance was found to a patient reported by Kozlowski et al. in 1993.

Abnormalities, Multiple↗
PubMed1998

Cumming syndrome: report of two additional cases.

We present two unrelated cases with a similar pattern of multiple congenital anomalies including limb shortening, long bone angulation, and cervical lymphocele. We believe these cases to represent additional examples of a syndrome first described by Cumming et al. (1986), and by Urioste et al. (1991) and Ming et al. (1997).

Abnormalities, Multiple↗
PubMed1998

Nephronophthisis associated with Ellis-van Creveld syndrome.

Ellis-van Creveld (EvC) and Jeune's asphyxiating thoracic dystrophy (ATD) are related disorders characterized by narrow thoracic cage and short-limbed dwarfism. Some patients have overlapping features of both ATD and EvC, indicating that these syndromes may be a part of a disease spectrum. Nephronophthisis has been occasionally reported in patients with ATD, but not with EvC syndrome. We report a patient who was diagnosed with EvC syndrome at birth. He developed hypertension at 5 months of age and gradually progressive renal failure, requiring renal transplantation at 8 years. Histopathological findings in the nephrectomy specimen were indicative of nephronophthisis. The association of nephronophthisis in a patient with EvC syndrome has not been reported previously. This association further supports the hypothesis that ATD and EvC syndromes are related and represent a spectrum of disorders.

Ellis-Van Creveld Syndrome↗
PubMed1998

Diverse mutations in the gene for cartilage oligomeric matrix protein in the pseudoachondroplasia-multiple epiphyseal dysplasia disease spectrum.

Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are autosomal dominant osteochondrodysplasias that result in mild to severe short-limb dwarfism and early-onset osteoarthrosis. PSACH and some forms of MED result from mutations in the gene for cartilage oligomeric matrix protein (COMP; OMIM 600310 [http://www3.ncbi.nlm. nih.gov:80/htbin-post/Omim/dispmim?600310]). We report the identification of COMP mutations in an additional 14 families with PSACH or MED phenotypes. Mutations predicted to result in single-amino acid deletions or substitutions, all in the region of the COMP gene encoding the calmodulin-like repeat elements, were identified in patients with moderate to severe PSACH. We also identified within this domain a missense mutation that produced MED Fairbank. In two families, one with mild PSACH and the second with a form of MED, we identified different substitutions for a residue in the carboxyl-terminal globular region of COMP. Both the clinical presentations of these two families and the identification of COMP-gene mutations provide evidence of phenotypic overlap between PSACH and MED. These data also reveal a role for the carboxyl-terminal domain in the structure and/or function of COMP.

Achondroplasia↗
PubMed1998

Localization of a multiple synostoses-syndrome disease gene to chromosome 17q21-22.

Multiple synostoses syndrome is an autosomal dominant disorder characterized by premature onset of joint fusions, which initially affect the interphalangeal joints, by characteristic facies, and by deafness. We performed linkage analysis on a large Hawaiian family with multiple synostoses syndrome. Because another autosomal dominant disorder, proximal symphalangism, shares some clinical symptoms with multiple synostoses syndrome and has been linked to markers at loci at chromosome 17q21-22, we tested the hypothesis that multiple synostoses syndrome is linked to the same chromosomal region. Using polymorphic markers from the proximal symphalangism interval, we conducted linkage analysis and showed that the multiple synostoses-syndrome phenotype is linked to the same chromosomal region. A maximum LOD score of 3.98 at recombination fraction of .00 was achieved for the marker at locus D17S787. Further genetic analysis identified individuals with recombinant genotypes, allowing localization of the disease gene within the interval D17S931-D17S792, a 16-cM region. These data provide evidence that multiple synostoses syndrome and proximal symphalangism may be allelic disorders.

Abnormalities, Multiple↗
PubMed1998

Lys650Met substitution in the tyrosine kinase domain of the fibroblast growth factor receptor gene causes thanatophoric dysplasia Type I. Mutations in brief no. 199. Online.

Thanatophoric dysplasia (TD) is one of the most common neonatal lethal skeletal dysplasias with micromelic shortening of the limbs, relative macrocephaly, flat vertebral bodies and a narrow thorax. TD has been divided into two types, type I (TD1) and II (TD2), based on clinical, radiological, histological, and molecular criteria. We identified a A to T heterozygous base subsitution at position 1949 predicted to cause a Lys650Met substitution in a term infant with TD1. This mutation has been previously described in one case of TD1 and three cases of severe achondroplasia with acanthosis nigricans and mental retardation. Interestingly, all cases with the Lys650Met mutation have the same unusual curvature of the tibia and/or fibula.

Amino Acid Substitution↗
PubMed1997

Brachydactyly-short stature-hypertension (Bilginturan) syndrome: report on two families.

We report on two families with autosomal dominant brachydactyly of hands and feet and hypertension. All affected members of the first family had proportionate short stature. However, the propositus and the affected relatives in the second family were only short compared to unaffected relatives. The hypertension was medically responsive in all cases. The propositus in the second family had poor compliance and a striking generalized vasculopathy. All patients were of normal intelligence and had a normal facial appearance. The brachydactyly-short stature-hypertension syndrome was first reported by Bilginturan et al. [1973] in a Turkish family and the families reported by us are Caucasian and Hispanic. The gene causing this condition in the original Turkish family was recently mapped to 12p. Our report expands our existing knowledge and the ethnic diversity of this syndrome.

Adult↗
PubMed1997

Neurologic abnormalities in the skeletal dysplasias: a clinical and radiological perspective.

The neurologic manifestations of the skeletal dysplasias are reviewed. Three important major groups are identified: Achondroplasia (cranio-cervical junction problems in infancy, spinal stenosis and neurogenic claudication in the adult). Type II collagenopathies (upper cervical spine anatomic and functional problems), and craniotubular and sclerosing bone dysplasias (osseous overgrowth with foraminal obstruction problems). The remainder of the well-identified 150 or so bone dysplasias are also evaluated in depth for their diverse neurologic abnormalities. The findings discussed are important both for the diagnosis and management of these patients.

Achondroplasia↗
PubMed1997

The Pointer syndrome: a new syndrome with skeletal abnormalities, camptodactyly, facial anomalies, and feeding difficulties.

We describe a brother and sister with a unique combination of skeletal findings including camptodactyly (phalangeal dislocations), facial anomalies, neonatal respiratory problems, and feeding problems due to poor suck. Metaphyseal splaying, osteopenia, endosteal bone apposition, campomelia, and multiple fractures characterize the other skeletal abnormalities. The parents are first cousins once removed and are unaffected. These cases appear to represent a previously undescribed autosomal recessive disorder.

Abnormalities, Multiple↗
PubMed1997

Lumbar gibbus in storage diseases and bone dysplasias.

OBJECTIVE: The objective of this study was to review the problem of lumbar gibbus in children with storage diseases and bone dysplasias utilizing plain films and MR imaging. MATERIALS AND METHODS: Clinical histories and radiographic images in five patients with storage diseases [four mucopolysaccharidosis (MPS) and one mucolipidosis] and two with achondroplasia were reviewed. The International Skeletal Dysplasia Registry (Los Angeles, Calif.), surveyed for all patients with lumbar gibbus and skeletal dysplasias, provided 12 additional cases. RESULTS: All patients had localized gibbus of the upper lumbar spine, characterized by anterior wedging and posterior displacement of the vertebrae at the apex of the curve, producing a beaked appearance. The curve, exaggerated in the sitting or standing position, was most severe in the two patients with MPS-IV (one of whom died). Both developed severe neurologic signs and symptoms requiring surgical intervention. In four patients, MR images demonstrated the apex of the curve to be at or below the conus. Two patients demonstrated anterior herniation of the intervertebral discs at the apex of the curve, though the signal intensity of the intervertebral discs was normal. CONCLUSION: Lumbar gibbus has important neurologic and orthopedic implications, and is most severe in patients with MPS. The etiology of the gibbus with vertebral beaking is multifactorial and includes poor truncal muscle tone, weight-bearing forces, growth disturbance and anterior disc herniation. The curve is generally at or below the conus. Neurologic complications are unusual, although orthopedic problems can arise. Due to their longer survival, patients with achondroplasia or Morquio's disease are more vulnerable to eventual gibbus-related musculoskeletal complications.

Achondroplasia↗
PubMed1997

The cervical spine in the skeletal dysplasias and associated disorders.

The cervical spine is an especially important area, not only for the diagnosis of the skeletal dysplasias, but also for the management of the patient. By the "cervical spine" I refer not only to the vertebral bodies and posterior elements of this region, but also to the neural elements contained within, especially the cervical cord. The spine is supported by a group of ligaments both anteriorly and posteriorly, with special fixation of the odontoid and C2 by a ligament which normally affixes it firmly to C1. Multiple things may go wrong with the development of the cervical spine. There may be abnormal development of the "vertebrae" in this region, ranging from hypoplasia to developmental failure and/or abnormal ossification of the cervical vertebrae; associated or unassociated odontoid hypoplasia; poor ligamental fixation of C2 resulting in C1-2 subluxation; abnormal development of the posterior processes; abnormal ligamental development or laxity with abnormal cervical kyphosis or lordosis; and, in the case of more fragile/brittle bone development (osteoporosis or increased bone density), fractures can lead to cervical spine problems. The skeletal dysplasias that involve cervical spine problems constitute about 35 of the 150 well-described disorders. These include certain families of disorders like the type II collagenopathies, as well as many individual disorders. It is very important for the clinician to be able to pilot patients through the various appropriate imaging modalities - conventional radiographs of the cervical spine; lateral flexion/extension views; CT; MRI - so that proper management and therapy will result.

Bone Diseases, Developmental↗
PubMed1997

The scapula as a window to the diagnosis of skeletal dysplasias.

Evaluation of the scapula can be useful in the diagnosis of skeletal dysplasias and helpful for the classification and delineation of new entities. A review of 2100 computerized cases of skeletal dysplasias in the International Skeletal Dysplasia Registry was performed. We found that the Luton type of platyspondylic lethal skeletal dysplasia differed radiographically from the San Diego type and Torrance type by the presence of two spikes at the inferior angle of the scapula. Hypoplasia of the body of the scapula, which is characteristic for campomelic dysplasia but not for kyphomelic dysplasia, is also present in Antley-Bixler syndrome. Radiographic and clinical similarities between campomelic dysplasia and Antley-Bixler syndrome suggest that they might be related disorders and that the latter condition should be included in the bent-bone dysplasia group. Similarity between the metaphyseal regions of the scapula and the metaphyses of the long tubular bones in the different types of short-rib polydactyly syndrome illustrates the importance of evaluation of the scapula in this group as well as in other well-defined or unknown osteochondrodysplasias.

Bone Diseases, Developmental↗
PubMed1997

Spondylo-mesomelic-acrodysplasia with joint dislocations and severe combined immunodeficiency: a newly recognised immuno-osseous dysplasia.

A newborn girl is described with an association of spondylo-acrodysplasia, mild short limbed dwarfism without significant metaphyseal changes, joint dislocations, and severe immune system dysfunction. This association is distinct from other known immuno-osseous dysplasias, including Schimke dysplasia, ADA deficiency with osseous changes, and Omenn phenotype with short limbed dwarfism.

Female↗
PubMed1996

Multiple vertebral segmentation defects: analysis of 26 new patients and review of the literature.

To further delineate and classify those forms of short trunk dwarfism characterized by multiple vertebral segmentation defects, we analyzed 26 new patients and reviewed 115 described in the literature. Three distinct entities were recognized based on radiographic and clinical findings. Jarcho-Levin syndrome is the lethal autosomal recessive form, characterized by a symmetric crab-like chest. Spondylocostal dysostosis is the benign autosomal dominant condition. Spondylothoracic dysostosis shows considerable clinical and radiographic overlap with spondylocostal dysostosis. Malformations observed in association with multiple vertebral segmentation defects are more common in the sporadic patients. Analysis of the 26 new individuals revealed that the body segment in which these nonvertebral malformations occur corresponds to the site of the vertebral segmentation defects.

Adolescent↗
PubMed1996

Epidemiology of osteochondrodysplasias: changing trends due to advances in prenatal diagnosis.

The osteochondrodysplasias (skeletal dysplasias) are a heterogeneous group of disorders characterized by abnormalities in cartilage and bone growth and development. Some of these disorders are detectable during the second trimester by sonographic techniques. We ascertained cases of osteochondrodysplasias in elective pregnancy terminations, stillborn infants older than 20 gestational weeks, and liveborn infants diagnosed by the fifth day of life as part of an ongoing active malformation surveillance program. Forty-nine cases of osteochondrodysplasias were identified among approximately 126,000 deliveries at Brigham and Women's Hospital (BWH) during a 15-year period (Feb. 16, 1972-Feb. 15, 1975; Jan. 1, 1979-Dec. 31, 1990). When cases delivered to women who had planned to deliver at another hospital but were transferred for high-risk care (transfers) were excluded, the prevalence rate was 2.14 cases per 10,000 deliveries. During the early period (1972-1975) no cases were suspected prenatally, while during the 1988-1990 period, 80% of all cases and 57% of cases delivered to women who had always planned to deliver at BWH (non-transfers) were suspected by ultrasonography. Birth status changed through our period of surveillance. In the final 3-year period (1988-1990), 40% of all cases and 29% of non-transfers with osteochondrodysplasias were pregnancy terminations, compared to none during the 1972-1975 period. The increasing frequency of pregnancy terminations complicated the diagnosis of these conditions. Despite extensive evaluation, a definitive diagnosis was not possible in 8 of 49 cases (16%). Biochemical and molecular genetic methods of diagnosis will continue to become more important if the current trend of wide utilization of prenatal sonography and termination of affected pregnancies continues.

Abortion, Induced↗