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Bruising: What to Know

Parents with bruised child

Bruising is common in children, and usually just a normal part of growing up – because children are playful and adventurous. For active toddlers, bruises on their shins, head bumps, and arms and legs are a normal part of growing up. As children get older and ride bikes and scooters, play sports and become more active, bruises can appear more often. So when is a bruise due to a minor injury and when is it more serious? Let's take a look.

What is a bruise?

A bruise occurs when blood vessels underneath the skin’s surface break. Blood leaks out of the broken vessels forming a bruise.

What causes a bruise?

Falls and injury
A bruise should be proportionate to the injury. For example, you would expect a larger bruise if your child falls out of a tree than if he trips and falls on the grass.

Child abuse
Bruises may be in specific shapes (belts, cigarette marks/burns, large bite marks.) They also may be in unusual places such as the ears, back, abdomen and cheeks. Bruising on infants who are not yet crawling or walking are not typical and a cause for concern.

Bleeding disorders
Bleeding disorders are caused by certain diseases or disorders, such as:

  • Von Willebrand Disease is the most common bleeding disorder and affects about 1% of the population. This may cause easy bruising, frequent nosebleeds, heavy menstrual bleeding, bleeding after surgery, bleeding gums.
  • Thrombocytopenia is a decrease in the number of platelets, and can cause easy or excessive bruising.
  • Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder, often triggered by a recent viral infection causing children to develop large bruises and pinpoint round spots known as petechiae.
  • Hemophilia A or B is a genetic disease that almost exclusively affects boys that is usually diagnosed prior to age 2-5 years old. It is associated with easy bruising, bleeding in joints, or excessive bleeding after a cut or dental procedure.
  • Henoch-Schonlein purpura (HSP) is an immune disorder which can cause abdominal pain, bloody stools, joint pain, and a distinctive rash on the child’s arms, legs and buttocks that look like bruises (purpura.)
  • Leukemia is the most common childhood cancer, and can cause bruising due to a low platelet count.
  • Vitamin K deficiency can cause bruising or bleeding. Vitamin K is needed for the clotting of blood, and is essential for the production of prothrombin (a clotting factor.)

Side effects of certain medications
Aspirin, some seizure medications, some antibiotics can cause bruising in children.

How long does a bruise last?

After initial injury, blood is flowing into the area and the area looks red. Within a day or two, the bruise changes to a deep blue/purple as the oxygen in the blood disappears. Around day 5, the bruise turns green, and then lightens to a yellow or yellow-brown color as it heals. Most bruises resolve by about two weeks.

When do I need to seek medical attention for a bruise?

Bruising is usually found on the bony areas, like the shins, knees, and elbows and forehead, especially in toddlers. If you notice bruises in unusual places, such as on the back, chest, cheeks, abdomen, or upper arms, you may want to consult your doctor. Things to look for include:

Bruises without any known cause or injury.
Large bruises that are raised and seem out of proportion to the injury that caused it, may be cause for concern. For example, the appearance of a very large bruise after a small bump against a table.

Extensive bruising.
Bruising that covers large portions of the body

Bruises that are not flat, feel like hard lumps and are larger than a quarter.
These type of bruises are called hematomas. Small hematomas may form, especially on the shins, but hematomas that don’t go away for weeks or months may need further evaluation and possible drainage.

Bruises in the presence of petechiae – also known as "little red dots."
These flat, pinpoint-sized red or purple dots are caused by minor bleeding under the skin. They can arise on the face after a viral infection, especially one associated with a lot of coughing or vomiting and should be evaluated. When there is an increase in bruising and petechiae, further testing is warranted to evaluate platelets or if there is a clotting problem.

Increased bruises along with pallor (pale appearance).
A blood count evaluation (CBC) is needed to look at numbers of red blood cells and platelets to see if anemia is present. Although leukemia is rare, this may be a symptom of the disease.

Increased bruising along with extra bleeding may be a sign of a bleeding disorder or platelet function problem.
When bruising is accompanied by frequent nose bleeds, bleeding from gums when brushing teeth, excessive bleeding after dental procedures or surgery, it may be a sign of a bleeding disorder or a platelet problem.

Sudden bruising
Bruises appear on a child who doesn't have a history of being a "bruiser."

Bruising along with a swollen joint or "goose egg."
For instance, a male infant/toddler who is starting to walk and develops a painful swollen joint after a fall may be a sign of hemophilia.

How do I care for a bruise at home?

Using a cold pack for 20 minutes every few hours for a couple of days can help with swelling and pain relief. Give an over-the-counter pain reliever for children if the bruise is tender or uncomfortable. Also, hugs and kisses do wonders – especially in small children!


Contributing author

Lauren Akers, D.O.
Cook Children's Hematology and Oncology – Prosper