Osteogenesis Imperfecta in Children
What is osteogenesis imperfecta in children?
Osteogenesis imperfecta (OI) is a
rare inherited (genetic) bone disorder that is present at birth. It's also known as
brittle bone disease. A child born with OI may have soft bones that break (fracture)
easily, bones that are not formed normally, and other problems. Symptoms may range
from
mild to severe.
There are at least 8 different
types of the disease. The types vary greatly, both within and between types. They
are
based on the type of inheritance (see below), and symptoms. These include findings
on
X-rays and other imaging tests. The OI types are:
-
Type I.
Mildest and most common type. About 50% of all affected children have this type.
There are few fractures and deformities.
-
Type
II.
Most severe type. A baby has very short arms and legs, a small
chest, and soft skull. They may be born with fractured bones. They may also have a
low birth weight and lungs that aren't well developed. A baby with type II OI often
dies in the birth parent's uterus or a few weeks after birth.
-
Type
III.
Most severe type in babies who don’t die as newborns. At birth, a
baby may have slightly shorter arms and legs than normal and arm, leg, and rib
fractures. The baby may also have a larger than normal head, a triangle-shaped face,
a deformed chest and spine, and breathing and swallowing problems. These symptoms
are
different in each baby.
-
Type IV.
Symptoms are between mild and severe. A baby with type IV may be
diagnosed at birth. They may not have any fractures until crawling or walking, with
most fractures occurring before puberty. The bones of the arms and legs may not be
straight. The child may not grow normally.
-
Type V.
Similar to type IV. Symptoms may be medium to severe. It is common to
have enlarged thickened areas (hypertrophic calluses) in the areas where large bones
are fractured.
-
Type VI.
Very rare. Symptoms are medium. Similar to type IV.
-
Type VII.
May be like type II or like type III. It's common to have shorter than
normal height. Also common to have shorter than normal upper arm and
thighbones.
-
Type VIII.
Similar to types II and III. Very soft bones and severe growth
problems.
What causes osteogenesis imperfecta in a child?
OI is passed on through the
genes. The different types are passed on in different ways. The gene may be inherited
from 1 or both parents. Or the gene can be passed on from an unexplained change
(spontaneous mutation) of a gene.
Most babies with OI have a defect
of 1 of 2 genes. These genes help in forming collagen. Collagen is a main part of
connective tissue that connects and supports the whole body, including the bones.
Because of the defect, there is not enough collagen. Or the collagen is abnormal.
What are the symptoms of osteogenesis imperfecta in a child?
The symptoms of OI vary greatly within and between types. Symptoms of OI include:
- Easily broken bones
- Bone deformities, such as bowing of
the legs
- Discoloration of the white of the eye
(sclera), may be blue, purple, or gray in color
- A barrel-shaped chest
- A curved spine
- Short stature
- A triangle-shaped face
- Loose joints
- Muscle weakness
- Skin that easily bruises
- Hearing loss in early adulthood
- Breathing problems
- Soft, discolored teeth
Many of these symptoms can be
caused by other medical conditions. Always see your child's healthcare provider for
a
diagnosis.
How is osteogenesis imperfecta diagnosed in a child?
Your baby's healthcare provider
will ask questions about your baby's medical history, your family and pregnancy history,
and your baby's current symptoms. They will examine your baby, looking for symptoms
of
OI. The milder forms of OI may be hard to diagnose in a baby.
Your baby's provider may refer you
to specialists with experience in diagnosing and treating OI. For example, your baby
may
be referred to a specialist in genetic conditions (geneticist) or in bone disorders
(orthopedist).
Your baby's healthcare provider or
the specialists may advise these tests:
-
X-rays.
These may show many changes, such as weak or deformed bones and
fractures.
-
Lab tests.
Blood, saliva, and skin may be checked. The tests may include gene
testing.
-
DEXA (dual
energy X-ray absorptiometry) scan.
This is a scan of the bones to check for softening.
-
Bone biopsy.
A sample of the hipbone is often checked. This test needs
anesthesia.
How is osteogenesis imperfecta treated in a child?
Treatment will depend on your child’s symptoms, age, and general
health. It will also depend on how bad the condition is.
The main goal of treatment is to
prevent deformities and fractures and reduce chronic pain. And, once your child gets
older, to allow them to function as independently as possible. Treatments for preventing
or correcting symptoms may include:
-
Bisphosphonate medicines.
These are medicines that help to strengthen bones and prevent fractures. They
may be used in most types of OI. They may be given by mouth or by IV (intravenous)
line into a vein.
-
Care of
fractures.
The lightest possible materials are used to cast fractured bones. To prevent
further problems, it's advised that a child start moving or using the affected area
as soon as possible.
-
Orthopedic
treatment.
This may include bracing and splinting. Surgery may also be
needed.
-
Rodding. Metal rods are inserted to help hold in place (stabilize) and
prevent deformities of long bones.
-
Dental
procedures.
Capping teeth, braces, and surgery may be needed.
-
Physical and
occupational therapy.
Both are very important in babies and children with OI.
-
Assistive
devices.
Wheelchairs and other custom-made equipment may be needed as babies get
older.
What are possible complications of osteogenesis imperfecta in a
child?
Complications may affect most body
systems in a baby or child with OI. The risk of complications depends on the type
and
severity of your baby's OI. Complications may include:
- Respiratory infections, such as pneumonia
- Heart problems, such as poor heart
valve function
- Kidney stones
- Joint problems
- Hearing loss
- Eye conditions and vision loss
How can I help my child live with osteogenesis imperfecta?
OI is a lifelong condition.
Managing it may include:
-
Preventing
fractures.
If your baby has medium to severe OI, they need to be
picked up, diapered, and dressed very carefully. Their position should be changed
throughout the day. As your baby gets older, it will be important to help them
prevent injuries. A physical or occupational therapist, as well as other healthcare
providers, can help.
-
Preventing
infection.
Your baby may be more likely to get colds and other respiratory infections. And
they may get sicker with an infection. Make sure your baby has all of their advised
vaccines (immunizations). During cold and flu season, keep your child away from
crowds. Make sure that you wash your hands and your child’s hands well. As your child
gets older, teach them how to do it.
-
Managing
pain.
Fractures and deformities can be very painful. Talk with your baby's healthcare
provider about pain medicine or other ways to reduce pain.
-
Coping with
challenges.
As your child gets older, they may have emotional and physical challenges.
-
Getting
regular medical and dental checkups.
Your baby will need regular checkups and tests. These include eye and dental
exams.
-
Managing
weight.
When your child gets older, they may gain weight because of
the decreased physical activity.
When should I call my child's healthcare provider?
Call the healthcare provider if
your child:
- Is injured
- Has changes in their behavior that may
mean an injury or other problem. For example, your baby may be fussy or
irritable.
- Has signs of a cold or flu, like a
fever, chills, or cough
Key points about osteogenesis imperfecta in children
- Osteogenesis imperfecta (OI) is an inherited (genetic) bone disorder that is present
at birth.
- It's also known as brittle bone
disease.
- A child born with OI may have soft bones that break (fracture) easily, bones that
are not formed normally, and other problems. Signs and symptoms may range from mild
to severe.
- The main goal of treatment is to prevent deformities and fractures.
- OI is a lifelong condition.
Next steps
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the visit, write down the name of a new diagnosis, and any new medicines, treatments,
or tests. Also write down any new instructions your provider gives you for your child.
- Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
- Know how you can contact your child’s
provider after office hours. This is important if your child becomes ill and you have
questions or need advice.