The Bottom Line

Kawasaki disease is a serious but treatable condition that inflames blood vessels throughout the body — including the arteries of the heart. It mainly affects children under 5. The key warning sign is fever lasting 5 or more days combined with specific skin and body changes. When treated promptly with IVIG (intravenous immunoglobulin) and aspirin, the risk of heart complications drops from 25% to less than 5%. This disease is the leading cause of acquired heart disease in children in developed countries, making early recognition critical.

What Is Kawasaki Disease?

Kawasaki disease is an acute inflammatory illness that causes widespread inflammation of blood vessels — a condition called vasculitis. It primarily affects children under 5 years old, though it can occur in older children. Boys are affected about 1.5 times more often than girls.

The disease affects approximately 9–10 per 100,000 children under age 5 in the United States, and up to 15–20 per 100,000 in Japan, where it is more common. It is the leading cause of acquired (not present at birth) heart disease in children in developed countries.

The cause remains unknown. The current leading theory is that an unidentified infectious agent (virus or bacteria) triggers an abnormal immune response in genetically susceptible children. The disease is not thought to spread easily between people.

Recognizing the Signs: The Diagnostic Criteria

Kawasaki disease is diagnosed based on clinical features because there is no single blood test that confirms it. Doctors look for fever lasting 5 or more days plus at least 4 of these 5 features:

1. Skin Rash

A widespread rash appears on the trunk and extremities, often within the first 5 days of fever. The rash is polymorphous — meaning it can look different from child to child. It may be blotchy, measles-like, or bumpy. It does not blister. The rash typically spares the face.

2. Eye Redness (Conjunctival Injection)

Both eyes become red and bloodshot — but without the discharge or pus typical of pink eye (conjunctivitis). This is almost universal in Kawasaki disease.

3. Mouth and Lip Changes

Classic oral signs include:

  • Bright red, cracked, or swollen lips
  • Strawberry tongue — the tongue becomes bright red and bumpy
  • Redness of the lining of the mouth

4. Hand and Foot Changes

In the acute phase: redness and swelling (edema) of the palms and soles. Children may refuse to use their hands or walk because of the discomfort. Later — about 1–2 months after the illness — the skin on the fingertips and toes peels off in a characteristic glove-like or sock-like pattern. This late peeling is highly suggestive of prior Kawasaki disease.

5. Swollen Lymph Node in the Neck

At least one lymph node in the neck measures more than 1.5 cm — usually on one side. This occurs in 50–75% of children with Kawasaki disease.

What About the Heart?

The most dangerous aspect of Kawasaki disease is coronary artery inflammation. The arteries that supply blood to the heart can become inflamed and develop aneurysms — balloon-like bulges that can lead to blood clots, heart attacks, or sudden cardiac death.

  • Without treatment: coronary aneurysms develop in 25% of children
  • With prompt IVIG treatment: this drops to less than 5%

An echocardiogram (ultrasound of the heart) is performed as soon as Kawasaki disease is suspected to check the coronary arteries. Follow-up echos are done at 6–8 weeks and 1 year after the illness.

Other Signs and Tests

Your child's doctor will order blood tests that typically show signs of significant inflammation — elevated ESR (erythrocyte sedimentation rate), elevated CRP (C-reactive protein), and elevated platelet count (especially during the second week of illness). These are markers of inflammation, not diagnostic on their own. Sterile pyuria (white cells in urine without infection) is sometimes found.

How Is Kawasaki Disease Treated?

Treatment should begin as soon as possible — ideally within 10 days of fever onset. Standard treatment is:

  • IVIG (intravenous immunoglobulin): A single high-dose infusion of 2 g/kg given in hospital. This is the cornerstone of treatment and dramatically reduces the risk of coronary damage.
  • Aspirin: High-dose aspirin is given alongside IVIG during the acute phase to reduce inflammation. (This is one of the few situations where aspirin is given to children.) After the fever resolves, lower-dose aspirin continues for weeks to months to prevent blood clots.

If a child does not respond to the first round of IVIG, additional IVIG, corticosteroids, or biologic medications may be used.

When to See a Doctor — Urgently

  • Your child has had a fever for 5 or more days that hasn't responded to fever-reducing medication
  • You notice the combination of red eyes, red/cracked lips, rash, and swollen hands or feet along with fever
  • Younger infants (under 6 months) with unexplained prolonged fever — Kawasaki can be atypical in very young babies
  • Your child was previously treated for Kawasaki and has any new chest pain or cardiac symptoms

Kawasaki disease is a medical emergency when heart involvement is present. Do not wait to seek care if you suspect it.

Frequently Asked Questions

Is Kawasaki disease contagious?

Current evidence does not support significant person-to-person spread of Kawasaki disease. While outbreaks have been documented in communities, it does not behave like a typical contagious illness. Most cases are isolated.

Will my child have permanent heart problems?

Most children treated promptly with IVIG have no lasting heart damage. Children who do develop coronary aneurysms are followed closely by cardiologists. Small aneurysms often resolve on their own over months to years. Larger aneurysms may require long-term medication and periodic imaging. Regular follow-up with a pediatric cardiologist is essential for these children.

Can Kawasaki disease happen twice?

Yes, though recurrence is uncommon — it happens in about 3% of cases. Children who have had Kawasaki once should still receive prompt evaluation for any future prolonged fever.

What is the peeling skin on my child's fingers — is it dangerous?

The peeling skin (desquamation) on the fingertips and toes that appears 1–2 months after the fever is a normal part of the recovery from Kawasaki disease. It is not dangerous, does not need treatment, and resolves on its own. It is actually a useful sign that can confirm a prior Kawasaki episode in a child who was not previously diagnosed.

References

  1. Paller AS, Mancini AJ. Hurwitz Clinical Pediatric Dermatology. 5th ed. Elsevier; 2016.
  2. McCrindle BW, Rowley AH, Newburger JW, et al. Diagnosis, treatment, and long-term management of Kawasaki disease. Circulation. 2017;135(17):e927-e999.
  3. Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. Elsevier; 2016.
  4. Rowley AH. Epidemiology and pathogenesis of Kawasaki disease. Front Pediatr. 2018;6:374.
  5. Newburger JW, Takahashi M, Gerber MA, et al. Diagnosis, treatment, and long-term management of Kawasaki disease. Circulation. 2004;110(17):2747-2771.
  6. Belay ED, Holman RC, Curns AT, et al. Kawasaki syndrome and myocarditis in the United States. Pediatr Infect Dis J. 2010;29(1):1-5.

Trusted Resources

Always consult your child's pediatrician or a board-certified dermatologist if you suspect Kawasaki disease. This condition requires urgent medical evaluation and hospital-based treatment.