The condition can develop suddenly, and it is diagnosed based on the combination of clinical features, as there are no specific tests that rule it in or rule it out. Kawasaki disease is associated with severe inflammation, and it is treated with intravenous immunoglobulin (IVIG), which lowers the immune reaction. The outcome is generally good, and most people have a full recovery.
Symptoms
Kawasaki disease can develop over the course of several weeks. Most of the time, the condition affects young children who are younger than five years old, but it can affect older children, and rarely, even adults.
Your child might only have one or a few symptoms as the condition progresses, which makes it hard for parents to recognize that there is a serious illness developing.
Typically, Kawasaki disease causes a high fever (between 101-104 degrees Fahrenheit) and four of the five following signs:
Redness, swelling, and/or peeling of the skin on the hands and feet A rash on the back, abdomen, and/or chest Eye swelling or redness Swelling, redness, sores, or peeling of the mouth, lips, and/or throat Swollen lymph glands, especially on the neck
Children are likely to be irritable and may also develop a rash or peeling of the skin in the groin area. Sometimes Kawasaki disease is also associated with diarrhea, vomiting, joint pain or swelling, pain with urination, neck stiffness or headaches.
When the disease affects the heart, it might not produce obvious signs of heart disease, but heart involvement can cause lightheartedness, shortness of breath, chest pain, loss of consciousness, or even a heart attack.
Disease Stages
There are three stages of the disease. The acute stage, which typically lasts for a few weeks, is the stage when symptoms are noticeable. Treatment for Kawasaki Disease is typically initiated during the acute stage.
The subacute stage is the recovery stage, and people may have persistent sore joints without other symptoms during this stage, which lasts for about a month. And the last stage is the convalescent stage. The convalescent stage lasts for several months, is characterized by mild symptoms or no symptoms, and lasts until the laboratory abnormalities resolve.
Causes
The cause of Kawasaki Disease is not known, but there are some factors that make it more likely to occur. Kawasaki Disease is not an infection, and it often develops during or after a mild viral or bacterial infection.
It is more common among people who have family members who have also had it. And there is a geographic clustering, with the highest occurrence in Japan, followed by Korea, and then Taiwan. This familial tendency and geographic pattern has led experts to suggest that there may be a genetic predisposition to Kawasaki Disease.
Inflammation
Kawasaki disease is associated with diffuse inflammation throughout the body that is believed to occur due to a high reactivity of the immune system.
It has been suggested that the inflammatory reaction could be an autoimmune response or an overreaction of the body’s immune system to a trigger, such as an infection. The inflammation produces the fever, redness, swelling, and other symptoms.
Vasculitis
Many of the symptoms are attributed to vasculitis, which is inflammation of the blood vessels. With Kawasaki Disease, the inflammation is extensive, and it has a tendency to target the medium sized blood vessels of the body.
And the vasculitis can affect blood vessels in the heart, potentially leading to life threatening blood clots and the possibility of long-term heart disease. Another rare vascular complication of Kawasaki Disease is the development of an aneurysm, which is an outpouching and weakening of a blood vessel.
Diagnosis
The diagnosis of Kawasaki Disease is based on assessment of the clinical symptoms. While there are no specific tests that can confirm or rule out the disease, some diagnostic tests are used to help identify complications and guide treatment.
Laboratory Tests
A blood test or urine test can identify signs of inflammation. A complete blood count (CBC) may show leukocytosis (elevated white blood count). Other laboratory signs of inflammation, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and liver function tests may be abnormal in Kawasaki Disease as well.
A urine test may show sterile pyuria—white blood cells in the urine without evidence of an infection.
Imaging Tests
Kawasaki Disease often causes swelling of the lymph nodes and it can cause swelling in other areas of the body, including the gallbladder. An imaging test such as a computerized tomography (CT) tests can help your child’s doctor assess areas of concern.
Specialized Tests
Certain complications of Kawasaki Disease need to be evaluated with specialized tests. For example, when there is a concern about dehydration due to vomiting or a decreased appetite, an electrolyte blood test can help identify early signs of dehydration that require treatment.
Vision changes caused by anterior uveitis, inflammation in the eye, can be diagnosed with an eye examination.
Heart Tests
If heart involvement is being considered, your child may need an electrocardiogram (EKG) or echocardiogram. And EKG is a non invasive test that assesses the heart rate and rhythm. An echocardiogram is a non invasive imaging test that can be used to visualize the anatomical structure of your heart in action as it moves.
And an angiogram is an invasive test that can help your medical team visualize an abnormally shaped blood vessel, such as an aneurysm.
Treatment
Kawasaki Disease is treated in the hospital inpatient setting, and it typically takes days or weeks to for the condition to resolve, even with treatment. The main treatment includes anti inflammatories which help alleviate the inflammation and vasculitis. And when there is an infection, targeted antibiotics or antivirals may be used to help resolve the infection.
In addition to medication that is used to reduce inflammation and treat any associated infection, children and adults with this condition may also receive IV fluids and other supportive treatments as needed.
Immune Suppression
Treatment of the Kawasaki Disease with a combination of IVIG and aspirin helps prevent complications from developing. The administration of IVIG is an infusion procedure in which immune proteins are injected into the vein to reduce the body’s excessive and harmful immune response in diseases like Kawasaki disease.
Aspirin reduces inflammation and is used to bring down the fever.
Sometimes corticosteroids or Remicade (infliximab) are used when the standard treatment is not effective. Other immunosuppressants used for treating the Kawasaki Disease include Cyclosporin, Cyclophosphamide, and Methotrexate.
Procedures
Serious heart and vascular problems may not improve with anti inflammatory treatment and can persist after the acute phase of the condition resolves. These vascular complications may require treatment with an interventional procedure, such as surgery or catheterization. A catheter is a tube that is inserted to reach, and possibly repair, and anatomical defect.
The outcomes are good, but Kawasaki Disease is the most common cause of acquired heart disease in the United States.
A Word From Verywell
When your child has an infection or a mild illness you can usually expect it to resolve without serious effects. While Kawasaki Disease generally has a good outcome, parents should seek medical attention right away if a child develops signs of the condition.