start-ver=1.4 cd-journal=joma no-vol=34 cd-vols= no-issue=3 article-no= start-page=152 end-page=161 dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=2025 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Osteogenesis imperfecta: pathogenesis, classification, and treatment en-subtitle= kn-subtitle= en-abstract= kn-abstract=Osteogenesis imperfecta (OI) is a congenital skeletal disorder characterized by varying degrees of bone fragility and deformities. Extraskeletal manifestations, such as blue sclera, dentinogenesis imperfecta, growth disturbance, hearing impairment, and muscle weakness, occasionally accompany OI. Many genes have been identified as causative of OI, such as the type I collagen gene and genes involved in the folding, processing, and crosslinking of type I collagen molecules, osteoblast differentiation, and bone mineralization. According to the discovery of the causative gene of OI, nosology and classifications have also been revised and the gdyadic approachh based nomenclature according to the severity and each causative gene of OI was recently adopted. Intravenous or oral bisphosphonates have been administered to treat bone fragility in children with OI and a reduction in the frequency of bone fractures has been reported. However, despite the increase of bone mineral density, evidence of bone fracture prevention is limited. Recently, excessive transforming growth factor ƒĄ signaling pathway and excessive endoplasmic reticulum stress have been reported as the pathogenesis of OI, and treatment strategies based on these pathogeneses have been developed. This review summarizes the molecular basis, transition of nosology and classification, status of bisphosphonate therapy, and development of treatment strategies. en-copyright= kn-copyright= en-aut-name=HasegawaKosei en-aut-sei=Hasegawa en-aut-mei=Kosei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= affil-num=1 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= en-keyword=fracture kn-keyword=fracture en-keyword=child kn-keyword=child en-keyword=bisphosphonate kn-keyword=bisphosphonate en-keyword=classification kn-keyword=classification en-keyword=treatment kn-keyword=treatment END start-ver=1.4 cd-journal=joma no-vol=34 cd-vols= no-issue=2 article-no= start-page=131 end-page=136 dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=2025 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Effect of calcium supplementation on bone deformity and histopathological findings of skin papules in a pediatric patient with vitamin D?dependent rickets type 2A: A case report en-subtitle= kn-subtitle= en-abstract= kn-abstract=Vitamin D?dependent rickets type 2A (VDDR2A) is an autosomal recessive disease caused by pathogenic variants of the vitamin D receptor (VDR) gene. VDDR2A rickets are usually resistant to native or active vitamin D treatment because of impaired active calcium absorption against the calcium concentration gradient, which is a ligand-dependent VDR action in the small intestine. Alopecia due to an impaired skin follicular cycle is occasionally observed in patients with VDDR2A. Among the pathogenic VDR variants, most in the DNA-binding domain and some in the ligand-binding domain, which affect the dimerization of VDR with the retinoic X receptor, are associated with alopecia. Herein, we report a case of VDDR2A caused by compound heterozygous pathogenic variants of the DNA-binding domain of VDR. Active vitamin D treatment did not ameliorate genu varum, rachitic changes in the roentgenogram, or abnormal laboratory findings. However, oral administration of calcium lactate dramatically improved these findings. The patient also experienced hair loss at two months of age and multiple papules on the skin at two yr of age, which did not improve with vitamin D or calcium supplementation. We also report the histopathological findings of skin papules in this patient. en-copyright= kn-copyright= en-aut-name=HasegawaKosei en-aut-sei=Hasegawa en-aut-mei=Kosei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MiyakeTomoko en-aut-sei=Miyake en-aut-mei=Tomoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KobashiMina en-aut-sei=Kobashi en-aut-mei=Mina kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=TetsunagaTomonori en-aut-sei=Tetsunaga en-aut-mei=Tomonori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=AgoYuko en-aut-sei=Ago en-aut-mei=Yuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=FutagawaNatsuko en-aut-sei=Futagawa en-aut-mei=Natsuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=MiyaharaHiroyuki en-aut-sei=Miyahara en-aut-mei=Hiroyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=HiguchiYousuke en-aut-sei=Higuchi en-aut-mei=Yousuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=MorizaneShin en-aut-sei=Morizane en-aut-mei=Shin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=TsukaharaHirokazu en-aut-sei=Tsukahara en-aut-mei=Hirokazu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= affil-num=1 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=2 en-affil=Department of Dermatology, Okayama University Hospital kn-affil= affil-num=3 en-affil=Department of Dermatology, Okayama University Hospital kn-affil= affil-num=4 en-affil=Department of Dermatology, Okayama University Hospital kn-affil= affil-num=5 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=6 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=7 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=8 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=9 en-affil=Department of Dermatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=10 en-affil=Department of Pediatrics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=rickets kn-keyword=rickets en-keyword=receptor kn-keyword=receptor en-keyword=alopecia kn-keyword=alopecia en-keyword=papules kn-keyword=papules en-keyword=calcium kn-keyword=calcium END start-ver=1.4 cd-journal=joma no-vol=32 cd-vols= no-issue=4 article-no= start-page=221 end-page=227 dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=2023 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Novel and recurrent COMP gene variants in five Japanese patients with pseudoachondroplasia: skeletal changes from the neonatal to infantile periods en-subtitle= kn-subtitle= en-abstract= kn-abstract=Pseudoachondroplasia (PSACH) is an autosomal dominant skeletal dysplasia caused by pathogenic variants of cartilage oligomeric matrix protein (COMP). Clinical symptoms of PSACH are characterized by growth disturbances after the first year of life. These disturbances lead to severe short stature with short limbs, brachydactyly, scoliosis, joint laxity, joint pain since childhood, and a normal face. Epimetaphyseal dysplasia, shortened long bones, and short metacarpals and phalanges are common findings on radiological examination. Additionally, anterior tonguing of the vertebral bodies in the lateral view is an important finding in childhood because it is specific to PSACH and normalizes with age. Here, we report five Japanese patients with PSACH, with one recurrent (p.Cys351Tyr) and four novel heterozygous pathogenic COMP variants (p.Asp437Tyr, p.Asp446Gly, p.Asp507Tyr, and p.Asp518Val). These five pathogenic variants were located in the calcium-binding type 3 (T3) repeats. In four of the novel variants, the affected amino acid was aspartic acid, which is abundant in each of the eight T3 repeats. We describe the radiological findings of these five patients. We also retrospectively analyzed the sequential changes in the vertebral body and epimetaphysis of the long bones from the neonatal to infantile periods in a patient with PSACH and congenital heart disease. en-copyright= kn-copyright= en-aut-name=HasegawaKosei en-aut-sei=Hasegawa en-aut-mei=Kosei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=FutagawaNatsuko en-aut-sei=Futagawa en-aut-mei=Natsuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=AgoYuko en-aut-sei=Ago en-aut-mei=Yuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MiyaharaHiroyuki en-aut-sei=Miyahara en-aut-mei=Hiroyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=HaradaDaisuke en-aut-sei=Harada en-aut-mei=Daisuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=MiyazawaMari en-aut-sei=Miyazawa en-aut-mei=Mari kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=YoshimotoJunko en-aut-sei=Yoshimoto en-aut-mei=Junko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=BabaKenji en-aut-sei=Baba en-aut-mei=Kenji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=MoriwakeTadashi en-aut-sei=Moriwake en-aut-mei=Tadashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=TanakaHiroyuki en-aut-sei=Tanaka en-aut-mei=Hiroyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=TsukaharaHirokazu en-aut-sei=Tsukahara en-aut-mei=Hirokazu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= affil-num=1 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=2 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=3 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=4 en-affil=Department of Pediatrics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=5 en-affil=Department of Pediatrics, JCHO Osaka Hospital kn-affil= affil-num=6 en-affil=Department of Pediatrics, Kochi Health Sciences Center kn-affil= affil-num=7 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=8 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=9 en-affil=Department of Pediatrics, Iwakuni Clinical Center, National Hospital Organization kn-affil= affil-num=10 en-affil=Department of Pediatrics, Okayama Saiseikai General Hospital kn-affil= affil-num=11 en-affil=Department of Pediatrics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=infant kn-keyword=infant en-keyword=skeleton kn-keyword=skeleton en-keyword=spine kn-keyword=spine en-keyword=cartilage kn-keyword=cartilage en-keyword=growth kn-keyword=growth END start-ver=1.4 cd-journal=joma no-vol=28 cd-vols= no-issue=4 article-no= start-page=155 end-page=158 dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20191019 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Novel AVPR2 variant in a male infant with nephrogenic diabetes insipidus who showed delayed head control en-subtitle= kn-subtitle= en-abstract= kn-abstract= en-copyright= kn-copyright= en-aut-name=HasegawaKosei en-aut-sei=Hasegawa en-aut-mei=Kosei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=IhoriyaHiromi en-aut-sei=Ihoriya en-aut-mei=Hiromi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=FutagawaNatsuko en-aut-sei=Futagawa en-aut-mei=Natsuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=HiguchiYousuke en-aut-sei=Higuchi en-aut-mei=Yousuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=TsuchiyaHiroki en-aut-sei=Tsuchiya en-aut-mei=Hiroki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=ShibataTakashi en-aut-sei=Shibata en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=HayashiYumiko en-aut-sei=Hayashi en-aut-mei=Yumiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=KobayashiKatsuhiro en-aut-sei=Kobayashi en-aut-mei=Katsuhiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=TsukaharaHirokazu en-aut-sei=Tsukahara en-aut-mei=Hirokazu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= affil-num=1 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=2 en-affil=Advanced Critical Care and Emergency Center, Okayama University Hospital kn-affil= affil-num=3 en-affil=Department of Pediatrics, Okayama University Hospital kn-affil= affil-num=4 en-affil=Department of Pediatrics, Okayama University Hospital, Okayama, Japan kn-affil= affil-num=5 en-affil=Department of Child Neurology, Okayama University Hospital kn-affil= affil-num=6 en-affil=Department of Child Neurology, Okayama University Hospital kn-affil= affil-num=7 en-affil=Department of Child Neurology, Okayama University Hospital kn-affil= affil-num=8 en-affil=Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences kn-affil= affil-num=9 en-affil=Department of Pediatrics, Okayama University Graduate School of Medicine Dentistry, and Pharmaceutical Sciences kn-affil= en-keyword=developmental delay kn-keyword=developmental delay en-keyword=polyuria kn-keyword=polyuria en-keyword= polydipsia kn-keyword= polydipsia en-keyword=fever kn-keyword=fever en-keyword=poor weight gain kn-keyword=poor weight gain END