Kawasaki disease (KD) is a childhood illness that makes the blood vessels in the body, particularly those that supply blood to the heart, become inflamed (vasculitis). The most common symptoms include prolonged fever, rash, bloodshot eyes, red cracked lips and tongue, and lymph node swelling. The exact cause of KD is unknown. The symptoms of KD often go away on their own, and the child recovers. Without medical evaluation and treatment however, serious damage to the blood vessels of the heart may develop and not be initially recognized.
Kawasaki disease is a childhood illness that causes blood vessels to become inflamed (vasculitis) and swell. Kawasaki disease is a serious illness because it can cause life-threatening inflammation of blood vessels that supply oxygen and nutrients to the heart (the coronary arteries). This complication can usually be prevented by early diagnosis and treatment.
Kawasaki disease is most common in children younger than 5 years old; however, older children can be affected as well. KD occurs more often among boys and is more commonly seen in the winter and spring months. The exact cause of KD is unknown, but it is suspected that it may be triggered by an infection. It may also occur in children who have a genetic predisposition to the disease. Kawasaki disease is not contagious.
The most common symptoms of Kawasaki disease are:
Children with Kawasaki disease may also have painful or swollen joints, extreme fussiness especially in younger children, and swelling of the gallbladder that can cause belly pain and vomiting.
How is KD diagnosed?
There is no specific test to diagnose Kawasaki disease. Rather, doctors diagnose Kawasaki disease based on a child’s symptoms and physical exam. A prolonged fever (i.e., more than five days) is often the first symptom that alerts a doctor to consider Kawasaki disease.
Lab tests may help with diagnosis. This may include:
These laboratory tests are helpful; however, the only way to make the diagnosis of Kawasaki disease is by meeting the clinical criteria for most of the signs and symptoms listed above, and making sure the child’s illness is not caused by something else, like an infection.
If a child is diagnosed with Kawasaki disease, he is also seen by a cardiologist. They will have an electrocardiogram (to assess the electrical system of the heart) and an echocardiogram (ultrasound of the heart). Even if these studies are normal, the child will receive treatment based on clinical symptoms and lab work.
There are two main treatments for Kawasaki Disease:
Parents are sometimes concerned about using aspirin in children due to the concern over the link between aspirin use and Reye syndrome. Reye syndrome is an inflammatory process that affects the brain and liver and has occurred in patients taking aspirin who are infected with chicken pox or influenza. Most doctors suggest that if your child is taking aspirin for a long period for any reason, he should have a flu shot to avoid influenza infection. If your child is on aspirin and they have been exposed to or have chicken pox, you should contact your doctor immediately for advice.
Long-term outcomes depend on how much the coronary arteries were affected by the disease.
Follow up care is very important because, often, damage to the coronary arteries does not show up until several weeks later. Fortunately, with appropriate treatment, most children do not have any long-term sequelae from KD.
Children that do have coronary artery involvement will need regular cardiology evaluations. The frequency of these visits can depend on the extent of coronary changes. With the right medical care, these patients also generally have a good outcome.
When children are being evaluated for Kawasaki disease, they may be seen by a rheumatologist. Since there is no specific test to diagnose Kawasaki, rheumatologists often help decide if a child’s illness is caused by Kawasaki disease or another condition.
Rheumatologists may also help treat children with Kawasaki disease who do not respond to the usual treatments above. In these children, doctors may use other medicines that rheumatologists commonly use to treat other diseases such as arthritis.
Reference: Myositis and You. Ed. Lisa Rider, MD, Lauren Pachman, MD, Frederick Miller, MD, Harriet Bollar, The Myositis Association, 2007.
Written March 2019 by the Pediatric Rheumatology Special Committee and reviewed by the American College of Rheumatology Communications and Marketing Committee.
This information is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis and treatment of a medical or health condition.