4 research outputs found
Osteogenesis imperfecta: pregled suvremenih spoznaja o radiologiji koŔtanoga sustava i nove genetske spoznaje
Osteogenesis imperfecta is a genetically and clinically heterogeneous disorder of bone and connective tissue characterized by osteoporosis, fragile bones, hyperextensible joints, dentinogenesis imperfecta, bluish coloration of the sclerae, and adult-onset hearing loss. Medical history, careful physical examination, radiographic features of fractures, and biochemical analysis of skin collagen are the four cornerstones of accurate diagnosis. As osteogenesis imperfecta affects the whole skeleton, radiologic diagnostic features could be seen on any bone at any age of the patient. A radiology specialist should be aware of subtle changes seen on radiographs of axial skeleton (i.e. skull, spine and pelvic bones) and appendicular skeleton (i.e. long and short bones of extremities) as well as of specific osteogenesis features (i.e. āpopcornā calcifications) and difficult differential diagnosis (i.e. hypertrophic callus formation versus osteosarcoma; child abuse fractures versus true osteogenesis imperfecta). About 300 different mutations have been identified within COL1A1 and COL1A2 genes that encode the chains of type I collagen. More than 90% of these are heterozygous single base pair mutations unique to the affected individuals within families. Depending on the location of the mutation within the collagen gene, these produce a variety of clinical pictures which range from mild (OI type 1), lethal (OI type 2) to severely deforming (OI type 3) and mildly deforming (OI type 4). Each of the four types has a common radiologic appearance that helps in establishing the diagnosis. However, recent findings have confirmed that new genes other than type I collagen could be responsible for three new types of OI (OI type 5; OI type 6 and rhizomelic OI). Here we describe the complexity of the phenotype-genotype correlation in OI, and the recently proposed new classification.Osteogenesis imperfecta (OI) je genetski i kliniÄki heterogena bolest kosti i vezivnoga tkiva s odrednicama: osteoporoza; lomljivost kostiju; labavost zglobova, dentinogenesis imperfecta; plaviÄaste bjelooÄnice i nagluhost u odrasloj dobi. KljuÄ toÄne dijagnoze su Äetiri bitna postupka: precizna anamneza; pažljiv fizikalni pregled; uoÄavanje radioloÅ”kih znaÄajka prijeloma i promjena kostiju i biokemijska analiza kolagena kože. UobiÄajena je podjela na Äetiri tipa OI: od blagog (tip 1), letalnog (tip 2) do teÅ”ko deformirajuÄeg (tip 3) i umjereno deformirajuÄeg oblika (tip 4). Svaki od Äetiri tipa ima zasebne radioloÅ”ke znaÄajke koje pomažu kod postavljanja toÄne dijagnoze i klasificiranja. DijagnostiÄko-radioloÅ”ki znaci postoje na cijelom miÅ”iÄno koÅ”tanom sustavu od novoroÄenaÄke do kasne životne dobi. Za radiologa je važno prepoznati brojne siÄuÅ”ne i specifiÄne promjene na rendgenogramima aksijalnog (lubanja, kraljeÅ”nica, zdjelica) i apendikularnog (kosti udova) skeleta. Znaci korisni u diferenciranju osteosarkoma prema stvaranju hipertrofiÄnog koÅ”tanog kalusa kod OI i drugi posebni znaci bolesti, primjerice metafizne āpopcornā kalcifikacije, prepoznaju se dobrom radioloÅ”kom obradom. Dosad je otkriveno oko 300 razliÄitih mutacija na COL1A1 i COL1A2 genima odgovornima za oblikovanje lanaca kolagena tip I. KliniÄka slika OI razlikuje se prema mjestu mutacije na genu za kolagen. Nedavni nalazi su potvrdili da i drugi geni, uz kolagen tip 1, mogu biti odgovorni za nastanak tri nova tipa OI: tip 5; tip 6 i rizomeliÄni tip OI. Nadalje, u tekstu je opisana složenost fenotipske i genotipske korelacije, kao i nedavno predložena nova klasifikacija OI
Osteogenesis imperfecta: pregled suvremenih spoznaja o radiologiji koŔtanoga sustava i nove genetske spoznaje
Osteogenesis imperfecta is a genetically and clinically heterogeneous disorder of bone and connective tissue characterized by osteoporosis, fragile bones, hyperextensible joints, dentinogenesis imperfecta, bluish coloration of the sclerae, and adult-onset hearing loss. Medical history, careful physical examination, radiographic features of fractures, and biochemical analysis of skin collagen are the four cornerstones of accurate diagnosis. As osteogenesis imperfecta affects the whole skeleton, radiologic diagnostic features could be seen on any bone at any age of the patient. A radiology specialist should be aware of subtle changes seen on radiographs of axial skeleton (i.e. skull, spine and pelvic bones) and appendicular skeleton (i.e. long and short bones of extremities) as well as of specific osteogenesis features (i.e. āpopcornā calcifications) and difficult differential diagnosis (i.e. hypertrophic callus formation versus osteosarcoma; child abuse fractures versus true osteogenesis imperfecta). About 300 different mutations have been identified within COL1A1 and COL1A2 genes that encode the chains of type I collagen. More than 90% of these are heterozygous single base pair mutations unique to the affected individuals within families. Depending on the location of the mutation within the collagen gene, these produce a variety of clinical pictures which range from mild (OI type 1), lethal (OI type 2) to severely deforming (OI type 3) and mildly deforming (OI type 4). Each of the four types has a common radiologic appearance that helps in establishing the diagnosis. However, recent findings have confirmed that new genes other than type I collagen could be responsible for three new types of OI (OI type 5; OI type 6 and rhizomelic OI). Here we describe the complexity of the phenotype-genotype correlation in OI, and the recently proposed new classification.Osteogenesis imperfecta (OI) je genetski i kliniÄki heterogena bolest kosti i vezivnoga tkiva s odrednicama: osteoporoza; lomljivost kostiju; labavost zglobova, dentinogenesis imperfecta; plaviÄaste bjelooÄnice i nagluhost u odrasloj dobi. KljuÄ toÄne dijagnoze su Äetiri bitna postupka: precizna anamneza; pažljiv fizikalni pregled; uoÄavanje radioloÅ”kih znaÄajka prijeloma i promjena kostiju i biokemijska analiza kolagena kože. UobiÄajena je podjela na Äetiri tipa OI: od blagog (tip 1), letalnog (tip 2) do teÅ”ko deformirajuÄeg (tip 3) i umjereno deformirajuÄeg oblika (tip 4). Svaki od Äetiri tipa ima zasebne radioloÅ”ke znaÄajke koje pomažu kod postavljanja toÄne dijagnoze i klasificiranja. DijagnostiÄko-radioloÅ”ki znaci postoje na cijelom miÅ”iÄno koÅ”tanom sustavu od novoroÄenaÄke do kasne životne dobi. Za radiologa je važno prepoznati brojne siÄuÅ”ne i specifiÄne promjene na rendgenogramima aksijalnog (lubanja, kraljeÅ”nica, zdjelica) i apendikularnog (kosti udova) skeleta. Znaci korisni u diferenciranju osteosarkoma prema stvaranju hipertrofiÄnog koÅ”tanog kalusa kod OI i drugi posebni znaci bolesti, primjerice metafizne āpopcornā kalcifikacije, prepoznaju se dobrom radioloÅ”kom obradom. Dosad je otkriveno oko 300 razliÄitih mutacija na COL1A1 i COL1A2 genima odgovornima za oblikovanje lanaca kolagena tip I. KliniÄka slika OI razlikuje se prema mjestu mutacije na genu za kolagen. Nedavni nalazi su potvrdili da i drugi geni, uz kolagen tip 1, mogu biti odgovorni za nastanak tri nova tipa OI: tip 5; tip 6 i rizomeliÄni tip OI. Nadalje, u tekstu je opisana složenost fenotipske i genotipske korelacije, kao i nedavno predložena nova klasifikacija OI