Kawasaki Disease

No one knows the causes of Kawasaki’s but researchers do not believe that it is contagious from person-to-person contact. Kawasaki disease occurs in 19 out of every 100,000 children in the United States.

Causes, Incidence, and Risk Factors

This disease was first discovered in Japan in 1967, and named after the doctor who identified it, Dr. Tomisaku Kawasaki. It is a poorly understood illness with an unknown cause, according to researcher Lawanna Brock. It does occur more commonly in that country for unknown reasons but affects children in the United States and other countries as well. Kawasaki disease is the second leading cause of heart disease in children. The leading cause is congenital heart defects. Researchers do not know why but it occurs more often in males than females with most of the patients being younger than five years of age. Many scientists and physicians believe that Kawasaki’s is the result of an autoimmune disorder. Other theories that have been proposed and studied are the bacteria or virus link and a genetic factor that increases the child’s susceptibility to this condition. Kawasaki disease results in inflammation of the blood vessels that can lead to aneurysms. Risk factors involved include a heart attack that results when an aneurysm develops but this is very rare. In the United States, the peak age of onset of Kawasaki’s is age 18 to 24 months. In Japan, it is considerably younger, with the peak age of onset 6 to 12 months.

There are three things that are known to increase your child’s risk of developing Kawasaki disease. These include:

Age – Children under five are more at risk for the condition.

Sex – Boys are more likely than girls to develop this disease.

Ethnicity – Those children of Asian descent (Japanese or Korean) have higher rates of Kawasaki            disease.

Signs and Symptoms

Most often, Kawasaki disease begins with a high persistent fever greater than 102 °F. This persistent fever lasts at least five days and is considered the classic diagnostic sign. Sometimes, this fever lasts for up to 2 weeks and does not respond well to normal doses of acetaminophen (Tylenol) or ibuprofen (Motrin). Another sign of the disease is peeling skin and this can be very frightening to parents. There are three phases to this disease and symptoms occur in an orderly fashion.

Phase I

·   Extremely bloodshot or reddened eyes (without pus or drainage)

·   Bright red, chapped, or cracked lips

·   Red mucous membranes in the mouth

·   A strawberry colored tongue

·   White coating on the tongue and prominent red bumps on the back of the tongue

·   Red palms of the hands and the soles of the feet

·   Puffy, swollen hands and feet

·   Skin rash on the middle of the body

·   Swollen lymph nodes (frequently only one lymph node is swollen), mostly of the neck

·   Irritability

Phase II

·   Skin peeling on the hands and feet (especially on tips of fingers and toes)

·   Joint pain and swelling, frequently on both sides of the body

·   Stomach ailments such as diarrhea, nausea and vomiting, and abdominal pain

·   Cough and runny nose

Phase III

During this phase, the signs and symptoms gradually go away. The child will have low energy levels but they slowly improve. Unless complications develop, this phase is around eight weeks.

Diagnostic Tests

Researcher Lawanna Brock found that there are no specific tests that will diagnose Kawasaki disease. The doctor bases the diagnosis on presentation of the classic symptoms. Most doctors will order several tests to rule out other ailments before concluding a diagnosis of Kawasaki’s. With most cases, children have a fever that lasts more than five days but not all cases. If this occurs the healthcare professional will want to further evaluate the child. The following tests may be performed:

Chest X-ray – To evaluate for pneumonia and other respiratory illness                                                                                                                                        Complete Blood Count (CBC) – To check for the body’s response to the infection                                                                                                                                    C-Reactive Protein (CRP) – To assess the degree of inflammation                                                                                                                 Echocardiogram (ECHO) – To test for heart function and evidence of complications                                                                                                                      Electrocardiogram (EKG or ECG) – To measure the child’s heartbeat                                                                                                                                                                Erythrocyte Sedimentation Rate (ESR) – To evaluate the severity of inflammation                                                                                                                  Urinalysis (UA) – To rule out other diseases and check for dehydration

Most of these tests are done to rule out other diseases that cause symptoms similar to the ones seen with Kawasaki disease. These illnesses include Juvenile Rheumatoid Arthritis, Scarlett Fever (due to streptococcal bacterial infection), Steven-Johnson Syndrome, measles, Toxic Shock Syndrome, Rocky Mountain Spotted Fever (a tick-born infection), and allergic drug reaction.

When to See a Doctor

As soon as you notice possible signs and symptoms, you should take your child to his healthcare provider or the hospital. This will reduce the risk of complications. The initial aim of treatment is to lower the fever and inflammation to prevent heart damage and complications. If your child has been sick with a fever, contact your pediatrician. Research supports treating Kawasaki disease within ten days of the onset of symptoms to greatly reduce the chances of complications and lasting damage.  Complications of the heart that could result from this condition include inflammation of the heart muscle (myocarditis), heart valve complications (mitral regurgitation), abnormal heart rhythm (dysrhythmia), and inflammation of the heart blood vessels (vasculitis). Lawanna Brock found that any of these complications could damage your child’s heart muscle and result in an aneurysm. Aneurysms result in a heart attack or life-threatening internal bleeding. Only a small number of children who develop Kawasaki’s have coronary artery and heart problems. Only a very small percentage of these children die from Kawasaki disease.

Treatment

Once the diagnosis of Kawasaki’s is made, your child will be admitted to the hospital. The doctors want to begin treatment immediately to prevent heart and blood vessel damage.

The main treatment is gamma globulin infusion. This is an immune protein that is given through the vein to lower the risk of heart trouble. High doses of aspirin are often given to treat the inflammation. Aspirin also decreases pain, lowers fever, and reduces joint inflammation. This is one of the only conditions where aspirin is used to treat a fever in children. Up to 25 percent of children may still develop complications in spite of treatment. New research has suggested that steroids will improve the child’s outcome but doctors agree that more studies are needed to confirm this.

Once the fever resides or lessens, your child may need to continue on a low-dose of aspirin for up to eight weeks. If he develops an aneurysm, the doctor may continue it longer. In some cases, children develop a flu-like illness or chicken pox infection during the treatment. Should this occur, your doctor will stop the aspirin because it has been linked to Reye’s Syndrome. Reye’s is a rare, serious illness that damages the liver, brain, and blood.

Continued Monitoring and Additional Procedures

The doctor may recommend follow-up tests to monitor your child’s heart for a while after he is released from the hospital. This may be done if there is any indication of heart complications or if the doctor simply wants to keep an eye on the situation. Your child will probably be referred to a pediatric cardiologist, a doctor who specializes in treating heart disease in kids. If a coronary aneurysm develops, your child will be put on anticoagulant drugs to help prevent clots from forming. In rare cases, a coronary artery angioplasty is necessary. This is required when the arteries have narrowed to the point that they impede blood flow to the heart. Some children need a stent placement which involves implanting a device into the clogged artery to help open it and decrease the chances of re-blockage. Often times stent placement accompanies angioplasty. In the most complicated cases, a child will have to have a coronary artery bypass graft, known as a ‘cabbage’ (CABG) or ‘open heart surgery’. This operation involves the re-routing of blood around the disease arteries of the heart by grafting a blood vessel from the leg to use.

Remember, with early recognition and treatment of this condition, full recovery is expected. You should find out all you can about Kawasaki disease so you will be more informed of the choices you have for treatment. Keep in mind that in most cases of Kawasaki’s, the child recovers completely and is back to normal within a few months. There are trained professionals that lend support to families at The Kawasaki Disease Foundation.