Page 18 - Delaware Medical Journal - June 2016
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Osteogenesis Imperfecta
K ayvon R. Golshani, MD; Meryl R. Ludwig, MD; Peter L. Cohn, MD; Richard Kruse, MD INTRODUCTION/EPIDEMIOLOGY
OI Type V in a child
Photo courtesy of Wikimedia Commons – ShakataGaNai
Osteogenesis imperfecta (OI) constitutes a heterogeneous group of symptoms due to mutations in type I collagen biosynthesis. The primary clinical features of the disease are high bone fragility and
low bone mass resulting in fractures and deformity. Approximately 90 percent of cases can be linked to defects in the COL1A1 and COL1A2 genes with more than 1,000 variants. The remaining 10 percent are linked in other known genes. OI has a prevalence of approximately 6 or 7 per 100,000 live births.1 There currently exists no cure for the disease and treatment is based on strengthening bone, preventing fractures, and maintaining mobility.
1788 by Ekman.2 The realization that the disease
tarda by Looser in 1906.3 Further study resulted in with blue sclera and autosomal dominant inheritance. Types II thru IV can be inherited in an autosomal dominant or recessive manner. Type II is lethal at birth due to fractures in utero and at birth resulting
on radiographic characteristics. Type III involves progressive deformity, varied appearance of sclera, and dentinogenesis imperfecta (DI). Type IV presents with normal sclera and variable phenotypic presentation.4 Further subtypes up to Type XIV have since been added based on other genetic etiologies and clinical manifestations.5 Types I and IV account for 50 to 90 percent of known cases.1
The subtypes were expanded when unique phenotypic
membrane led to further genetic research expanding the types to VII. OI type V was added to the Sillence
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Del Med J | June 2016 | Vol. 88 | No. 6
