OSTEOGENESIS IMPERFECTA (OI) - Type II

Osteogenesis Imperfecta Congenita (OIC); Vrolik Disease (OI Type 2A)

Osteogenesis Imperfecta (OI) is a group of genetic disorders that mainly affect the bones. The term “osteogenesis imperfecta” means imperfect bone formation. People with this condition have bones that break easily, often from mild trauma or with no apparent cause. Multiple fractures are common, and in severe cases, can occur even before birth. Milder cases may involve only a few fractures over a person's lifetime.

There are at least eight recognized forms of OI, designated type I through type VIII. The types can be distinguished by their signs and symptoms, although their characteristic features overlap. Type I is the mildest form of OI and type II is the most severe; other types of this condition have signs and symptoms that fall somewhere between these two extremes. Increasingly, genetic factors are used to define the different forms of OI.

Diagnostic testing: Ultrasound can often detect severe cases of OI during pregnancy. The severe form of OI Type II can be seen on ultrasound when the fetus is as young as 16 weeks. Genetic testing may be able to identify the mutation.

Physical findings: More severe forms of OI cause frequent bone fractures that may begin before birth and result from little or no trauma. Additional features of these conditions can include:

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  Blue sclerae;

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  Short stature;

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  Hearing loss;

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  Respiratory problems; and

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  A disorder of tooth development called dentinogenesis imperfecta.

The most severe forms of OI, particularly type II, can include an abnormally small, fragile rib cage and underdeveloped lungs. Infants with these abnormalities have life-threatening problems with breathing and often die shortly after birth.

ICD-9: 756.51

OI Type II infants have life-threatening problems with breathing and often die shortly after birth.

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  Genetic testing for mutations in the COL1A1 and COL1A2 genes responsible for collagen formation, or skin biopsy analysis; and

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  Physical and imaging findings consistent with OI Type II diagnosis.