Published: 18 Jun 2025

ICD9: 446.1      ICD10: M30.3      ICD11: 4A44.5

Kawasaki disease (KD), also known as mucocutaneous lymph node syndrome, is a rare condition that primarily affects young children.
It's characterized by inflammation of blood vessels throughout the body. While the exact cause remains unknown, it's believed to be triggered by an infection in genetically predisposed individuals.

Here's a breakdown of key aspects of Kawasaki Disease:

Key Characteristics:

Affects Blood Vessels: KD primarily targets medium-sized arteries, particularly the coronary arteries (those supplying blood to the heart muscle). Inflammation in these arteries can lead to weakening, dilation (aneurysm formation), and potentially blood clots.

Primarily Affects Young Children: The majority of cases occur in children under 5 years old. It is rare in children older than 8-10 years old.

Diagnosis based on Clinical Criteria: There's no specific diagnostic test for KD. Doctors diagnose it based on a cluster of signs and symptoms.

Signs and Symptoms:

To be diagnosed with Kawasaki disease, a child typically needs to have a fever lasting for at least 5 days *plus* at least four of the following five criteria:

1. High Fever: A persistent fever, often exceeding 102°F (39°C), lasting for at least 5 days. The fever often doesn't respond well to typical fever-reducing medications.

2. Rash: A polymorphic (variable) rash, often on the trunk of the body. It can look like measles, scarlet fever, or hives. The rash is usually not blistering.

3. Changes in Hands and Feet:
Redness and Swelling: Redness and swelling of the hands and feet, particularly in the acute phase.
Desquamation (Peeling): Peeling of the skin on the fingers and toes, especially around the nails, usually occurs later, during the convalescent phase.

4. Conjunctivitis: Bilateral (affecting both eyes) conjunctivitis (redness of the eyes) without pus or discharge.

5. Changes in the Mouth:
Red, Cracked Lips: Lips become red, dry, and cracked.
"Strawberry Tongue": The tongue becomes red and bumpy, resembling a strawberry.
Redness of the Mouth and Throat: The lining of the mouth and throat may appear red.

Other common, but not required, symptoms include:*

Cervical Lymphadenopathy: Enlarged lymph nodes in the neck, usually only on one side.
Irritability: Children with KD are often extremely irritable and difficult to comfort.
Abdominal Pain, Vomiting, Diarrhea: Gastrointestinal symptoms can occur.
Joint Pain: Arthritis or joint pain can sometimes be present.
Urethritis: Inflammation of the urethra, particularly in males.

Complications:

The most serious complication of KD is heart disease. Specifically:

Coronary Artery Aneurysms: Inflammation weakens the walls of the coronary arteries, leading to bulging (aneurysm formation). Large aneurysms can increase the risk of blood clots, heart attack, or sudden death.
Myocarditis: Inflammation of the heart muscle.
Pericarditis: Inflammation of the sac surrounding the heart.

Diagnosis:

As mentioned, diagnosis is clinical. Doctors consider the signs and symptoms, and also may perform:

Blood Tests: Complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and liver function tests (LFTs) can help detect inflammation.
Echocardiogram (ECHO): An ultrasound of the heart to assess the coronary arteries and heart function. This is crucial for detecting aneurysms. Echocardiograms are typically repeated at intervals to monitor the condition of the heart.
Electrocardiogram (ECG/EKG): A test that records the electrical activity of the heart.

Treatment:

The primary goals of treatment are to reduce inflammation and prevent heart complications. The standard treatment is:

Intravenous Immunoglobulin (IVIG): A concentrated solution of antibodies administered through a vein. IVIG helps to suppress the inflammatory response and reduce the risk of coronary artery aneurysms. It's most effective when given within the first 10 days of illness.
High-Dose Aspirin: Aspirin is used for its anti-inflammatory and antiplatelet effects. Initially given in high doses to reduce inflammation, it's later reduced to a low dose to prevent blood clots.
Corticosteroids: Sometimes used for severe cases, or when IVIG is not effective.

Follow-Up:

Children who have had KD need ongoing monitoring by a cardiologist to assess the health of their heart, particularly the coronary arteries. This often involves periodic echocardiograms. Children with aneurysms may need long-term medication, such as blood thinners, and lifestyle modifications.

Prognosis:

With prompt and appropriate treatment, most children with KD recover fully and have no long-term heart problems. However, if left untreated or if aneurysms develop, the risk of serious heart complications is significant.

In summary, Kawasaki disease is a serious illness that requires prompt diagnosis and treatment to prevent long-term heart damage. If you suspect your child may have KD, seek medical attention immediately.