Osteogenesis imperfecta type V: clinical and radiographic manifestations in mutation confirmed patients.

Osteogenesis imperfecta (OI) type V is a specific OI phenotype with interosseous membrane calcification of the forearm and hyperplastic callus formation as typical features. The causative gene mutation for OI type V has been recently discovered. The purpose of this report is to review the clinical and radiographic characteristics of mutation confirmed OI type V in detail. Sixteen (nine familial and seven sporadic) patients were enrolled in the study. Blue sclera and dentinogenesis imperfecta were not evident in any patient. However, hypodontia in the permanent teeth, ectopic eruption, and short roots in molars were additionally observed in 11 patients. Of the radiographic abnormalities, cortical thickening and bony excrescence of interosseous margin of the ulna was the most common finding, followed by overgrowth of the olecranon and/or coronoid process of the ulna. Slender ribs and sloping of the posterior ribs with or without fractures were also a consistent finding. Hyperplastic callus was detected in 75% of patients and was commonly encountered at the femur. Heterotopic ossification in the muscles and tendon insertion sites were noted in four patients, which resulted in bony ankylosis or contracture of joints. The current study confirms common clinical and radiographic findings of OI type V and reports additional phenotypic information. These observations provide clues to recognize OI type V more promptly and guide to direct targeted molecular study. © 2013 Wiley Periodicals, Inc.

Osteogenesis imperfecta Type VI with severe bony deformities caused by novel compound heterozygous mutations in SERPINF1.

Osteogenesis imperfecta (OI) comprises a heterogeneous group of disorders characterized by bone fragility, frequent fractures, and low bone mass. Dominantly inherited COL1A1 or COL1A2 mutations appear to be causative in the majority of OI types, but rare recessively inherited genes have also been reported. Recently, SERPINF1 has been reported as another causative gene in OI type VI. To date, only eight SERPINF1 mutations have been reported and all are homozygous. Our patient showed no abnormalities at birth, frequent fractures, osteopenia, and poor response on pamidronate therapy. At the time of her most recent evaluation, she was 8 yr old, and could not walk independently due to frequent lower-extremity fractures, resulting in severe deformity. No clinical signs were seen of hearing impairment, blue sclera, or dentinogenesis imperfecta. In this study, we describe the clinical and radiological findings of one Korean patient with novel compound heterozygous mutations (c.77dupC and c.421dupC) of SERPINF1.

Two novel insulin receptor gene mutations in a patient with Rabson-Mendenhall syndrome: the first Korean case confirmed by biochemical, and molecular evidence.

Rabson-Mendenhall syndrome (RMS) is a rare syndrome manifested by extreme insulin resistance with hyperinsulinemia, acanthosis nigricans, tooth dysplasia and growth retardation. Our patient was first noted at the age of 8 months due to pigmentations on skin-folded areas. Initial laboratory tests showed normal fasting glucose (69 mg/dL). Fasting insulin level was severely elevated, up to 554.6 µIU/mL, and c-peptide level was increased, up to 13.81 ng/mL. However, hemoglobin A1c was within normal range (4.8%). He is now 11 yr old. His growth development followed the 5-10th percentile and oral hypoglycemic agents are being administered. The last laboratory results showed insulin 364.1 µIU/mL, C-peptide 4.30 ng/mL, and hemoglobin A1c 7.6%. The boy was a compound heterozygote for the c.90C > A and c.712G > A mutations of the insulin receptor gene, INSR, which are nonsense and missense mutations. In summary, we report the first Korean case of RMS, which was confirmed by two novel mutations of the INSR.

Clinical Characteristics of Autosomal Dominant GJA1 Missense Mutation Linked to Oculodentodigital Dysplasia in a Korean Family.

PURPOSE: We aimed to present a comprehensive assessment of the ophthalmic characteristics of genetically confirmed oculodentodigital dysplasia (ODDD) in 4 members of a single Korean family across 3 generations. PATIENTS AND METHODS: The characteristics of 4 affected ODDD patients were evaluated. Comprehensive ophthalmic and medical examinations were performed in 3 patients including the proband, together with genetic analysis, and retrospective chart review was conducted for an affected ancestor. For genetic analysis, targeted gene panel sequencing was conducted using genomic DNA extracted from peripheral blood. RESULTS: All affected individuals in this family showed shared ophthalmic abnormalities of microcornea, microphthalmia, elevated intraocular pressure, and shallow anterior chamber, all of which have been reported as typical ocular features of ODDD. Myopic refractive error despite short axial length and thick cornea were highlighted as new findings of ODDD. Facial abnormalities were common in all affected members, but their fingers were normal. Severity of glaucoma was different among the affected individuals and seemed to depend on elevation of intraocular pressure, which occurred in narrow, but open-angle. Genetic analysis revealed the presence of c.119C>T (p.Ala40Val) in GJA1, which is responsible for ODDD, but not found in the control population. CONCLUSIONS: This report describes detailed ocular characteristics in a genetically confirmed ODDD family, including unreported findings of thick cornea and myopic refractive error despite short axial length. The ocular features derived from the A40V mutation in GJA1 showed complete penetrance, suggesting a possible role of Cx43 in regulation of IOP and pathogenesis of glaucoma.

Comprehensive study on the roles of released ions from biodegradable Mg-5 wt% Ca-1 wt% Zn alloy in bone regeneration.

We report here the effect of micro-environmental changes from biodegradable magnesium alloys on the activities of cells - osteoblasts, osteoclasts and macrophages - which play critical roles in each phase of the bone-regeneration process. Despite positive bone formation effects from several in vivo studies, minimal progress has been made in identifying underlying mechanisms through in vitro studies, which are currently concentrated on osteoblastic activities. The observed in vitro and in vivo results indicated that alkaline pH and released magnesium and zinc ions derived from Mg-5 wt% Ca-1 wt% Zn alloy biodegradation promote the progress of bone formation. In contrast, alkaline pH and magnesium ions remarkably suppressed osteoclastic activities and pro-inflammatory cytokine production, closely related to osteolysis and prosthesis failure. Findings from the present study conclude that the degradation of Mg-5 wt% Ca-1 wt% Zn alloys can promote new bone formation by simultaneously affecting the complex combination of variable cellular activities and phases. Copyright © 2016 John Wiley & Sons, Ltd.

First Korean Case of Infantile Hypophosphatasia with Novel Mutation in ALPL and Literature Review.

Hypophosphatasia is a rare hereditary disorder characterized by defective bone and tooth mineralization and deficiency of tissue non-specific alkaline phosphatase activity. The prognosis for the infantile form is poor, with approximately 50% of patients dying within the first year of life from respiratory failure. We describe the clinical and biochemical findings as well as the molecular analysis of a Korean boy with infantile hypophosphatasia and present a literature review. A 1-month-old boy visited the clinic because of poor feeding, frequent vomiting, hypotonia, and failure to thrive from birth. Laboratory tests revealed high total calcium, low phosphorous, low alkaline phosphatase, low parathyroid hormone, and normal 25-hydroxyvitamin D. Intravenous hydration with normal saline was started, and dietary calcium intake was restricted. Skeletal X-rays showed a markedly increased distance of the anterior fontanelle, impaired mineralization, and rachitic changes in the metaphyses. By Sanger sequencing of the ALPL gene, we identified two heterozygous variants, including a missense (c.334G>A; p.Gly112Ser) and a nonsense (c.1039C>T; p.Gln347*) variant. The c.334G>A (p.Gly112Ser) variant had previously been reported in a patient with lethal type hypophosphatasia, while the nonsense c.1039C>T (p.Gln347*) variant was novel. In the current case, the accurate diagnosis and prompt intervention-including dietary calcium intake restriction, tracheostomy to prevent progression to respiratory failure, and fundoplication with gastrostomy to ensure the administration of adequate calories-seemed to play an important role for avoiding preventable morbidity and premature mortality.

Osteogenesis imperfecta Type I caused by a novel mutation in the start codon of the COL1A1 gene in a Korean family.

Osteogenesis imperfecta (OI) comprises a heterogeneous group of disorders characterized by susceptibility to bone fractures ranging in severity from perinatal death to a subtle increase in fracture frequency. We report the case of a patient who appeared healthy at birth and did not experience any fractures until 12 months of age. We observed blue sclera, frequent fractures without commensurate trauma, nearly normal stature, the absence of dentinogenesis imperfecta, no bony deformity, and no limitation of mobility in the patient--all characteristics suggestive of OI Type I. The patient's mother also had blue sclera and a history of frequent fracture episodes until the age of 15 years. A novel COL1A1 missense mutation (c.2T>G) disrupting the start codon of the gene (ATG to AGG (Met1Arg)) was found in the patient and his mother.

Clinical, radiologic, and genetic features of Korean patients with Mucopolysaccharidosis IVA.

PURPOSE: Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is rare lysosomal storage disorder caused by N-acetylgalactosamine-6-sulfatase (GALNS) deficiency. Only a few MPS IVA cases have been reported in the Korean literature; there is a paucity of research about clinical or radiologic findings for this disorder. Therefore, we studied clinical findings, radiological features, and genetic data of Korean MPS IVA patients for determining factors that may allow early diagnosis and that may thus improve the patients' quality of life. METHOD: MPS IVA was confirmed via assay for enzymatic activity of leukocytes in 10 patients. The GALNS gene was analyzed. Patients' charts were retrospectively reviewed for obtaining clinical features and evaluated for radiological skeletal surveys, echocardiography, pulmonary function test, and ophthalmologic test results. RESULT: Nine patients had severe clinical phenotype, and 1 had an intermediate phenotype, on the basis of clinical phenotype criteria. Radiologic findings indicated skeletal abnormalities in all patients, especially in the hips and extremities. Eight patients had an odontoid hypoplasia, and 1 showed mild atlantoaxial subluxation and cord myelopathy. Genetic analysis indicated 10 different GALNS mutations. Two mutations, c.451C>A and c.1000C>T, account for 37.5% (6/16) and 25% (4/16) of all mutations in this samples, respectively. CONCLUSION: An understanding of the clinical and radiological features involved in MPS IVA may allow early diagnosis of MPS IVA. Adequate evaluations and therapy in the early stages may improve the quality of life of patients suffering from skeletal abnormalities and may reduce life-threatening effects of atlantoaxial subluxation.