Monday, February 26, 2007

Osteogenesis Imperfecta (Brittle Bone Disease)

Osteogenesis Imperfecta (OI) or better known as Brittle Bone Disease, is a congenital disease, meaning, it is present at birth.Source . This disease is often misinterperted with Child Abuse as the of fracture that are almost the same.

Example of OI and Child Abuse typical bone fractures:

  • fractures in multiple stages of healing
  • rib fractures
  • spiral fractures
  • fractures for which there is no adequate explanation of trauma.


The disease is classified by type:

  • Type 1 - Mild -- The person has a normal life expectancy.
  • Type 2 - Lethal -- The baby is born dead or dies shortly after birth.
  • Type 3 - Progressively deforming -- Life expectancy is shorter than normal.
  • Type 4 - Moderately severe, but varies greatly -- Most people have a normal lifespan.
  • Type 5 - Moderately deforming --Bones are somewhat fragile. This type is inherited from a parent.
  • Type 6 - Moderately to severely deforming --Bones are somewhat fragile. The cause is unknown.
  • Type 7 -- Moderately deforming --Bones are somewhat fragile. This type is found only in a small community of Native Americans.


Alternative names: Brittle bone disease

Definition :Osteogenesis imperfecta is a condition causing extremely fragile bones.

Causes, incidence, and risk factors :
Osteogenesis imperfecta (OI) is a congenital disease, meaning it is present at birth. It is caused by a genetic defect that affects type 1 collagen, an important building block of bone. This defect can occur in several ways.

The defect may be inherited from a mother or father with OI.

It may be caused by a mutation in the egg or sperm that created the child. In this case, neither parent has the gene for OI or the disease itself.

It may be inherited from a parent with eggs or sperm that carry the gene for OI, even if that parent does not have the disease.

In a person with OI, all bones are weak. How this affects the person varies greatly. For example, babies with type 2 OI rarely survive, yet type 1 OI may be so mild that the disease never produces symptoms.

Although their bones are fragile, not everyone with OI breaks a bone. Some people with OI also lose their hearing early in life. The whites of their eyes may have a blue tint (blue sclerae).

Signs and tests:
A physical examination may confirm fractures, deformities, and other symptoms.

Bone X-Ray may show many healed fractures.

The diagnosis of OI is made by collagen studies done on a skin punch biopsy. Family members may be given a DNA blood test. Pregnant women may have a DNA test done using prenatal chorionic villus samples (CVS) to diagnose the baby before it is born.

Severe OI can be seen on ultrasound when the fetus is as young as 16 weeks.

( , Febuary2006)



No comments:

Subscribe to my blog lah...

Enter your email address:

Delivered by FeedBurner