Atypical Presentation of Kawasaki Disease in a 4-Year-Old Child

Abstract

Kawasaki disease is an acute systemic vasculitis that primarily affects children under five years of age. Early diagnosis is critical because delayed treatment can lead to coronary artery complications. However, some children present with incomplete or atypical clinical features, making diagnosis challenging. This case report describes a four-year-old child who presented with prolonged fever and nonspecific symptoms and was later diagnosed with atypical Kawasaki disease. Early treatment with intravenous immunoglobulin (IVIG) resulted in rapid clinical improvement and prevented cardiac complications.

Introduction

Kawasaki disease is a medium-vessel vasculitis of unknown etiology that predominantly affects young children. It is one of the leading causes of acquired heart disease in children in developed countries.

The disease is characterized by prolonged fever and mucocutaneous inflammation. Classic diagnostic criteria include fever lasting at least five days, bilateral conjunctival injection, changes in the lips and oral cavity, polymorphous rash, cervical lymphadenopathy, and changes in extremities.

Some children present with incomplete Kawasaki disease, where not all diagnostic criteria are present. In such cases, laboratory investigations and echocardiography help confirm the diagnosis. Early treatment with intravenous immunoglobulin significantly reduces the risk of coronary artery aneurysms.

Case Presentation

Patient Information

Age: 4 years

Gender: Male

Birth history: Full-term normal vaginal delivery

Birth weight: 3.0 kg

Past medical history: No previous significant illnesses

Immunization status: Up to date according to the national immunization schedule.

Presenting Complaint

The child presented with fever for six days, red eyes, skin rash, irritability, and decreased appetite.

History of Present Illness

The illness began with high fever reaching 39°C that persisted despite antipyretics. Three days later the parents noticed redness of both eyes without discharge and a generalized rash over the trunk and limbs. Additional symptoms included swelling of the hands and feet, cracked lips, irritability, and decreased activity, prompting hospital evaluation.

Physical Examination

Temperature: 39°C

Heart rate: 120 beats/min

Respiratory rate: 26 breaths/min

Blood pressure: 100/65 mmHg

Clinical findings included bilateral non-purulent conjunctival injection, dry cracked lips, strawberry tongue, diffuse maculopapular rash, swelling of hands and feet, and cervical lymphadenopathy approximately 1.5 cm in size.

Investigations

White blood cell count: 16,500/mm³

Hemoglobin: 10.8 g/dL

Platelets: 480,000/mm³

C-reactive protein: Elevated

Erythrocyte sedimentation rate: Elevated

Liver enzymes: Mildly elevated

Urinalysis: Sterile pyuria

Echocardiography revealed mild dilation of the left coronary artery with no aneurysm formation. These findings supported the diagnosis of atypical Kawasaki disease.

Management

The child was admitted and treated according to Kawasaki disease management guidelines.

Intravenous immunoglobulin (IVIG) was administered as a single dose of 2 g/kg over 12 hours. High-dose aspirin (80 mg/kg/day) was started during the acute inflammatory phase. The patient was closely monitored for fever resolution and potential cardiac complications with serial examinations and cardiac imaging.

Outcome and Follow-Up

The fever resolved within 24 hours of IVIG administration and the child showed significant clinical improvement. Rash and conjunctival redness gradually resolved over several days. Follow-up echocardiography two weeks later demonstrated normal coronary artery dimensions. The child continued low-dose aspirin therapy for six weeks and remained clinically stable.

Discussion

Kawasaki disease is a systemic vasculitis that affects medium-sized arteries, particularly the coronary arteries. Although the exact cause remains unknown, infectious triggers and immune-mediated mechanisms are suspected.

If untreated, approximately 20–25% of patients may develop coronary artery aneurysms. Early treatment with intravenous immunoglobulin reduces this risk to less than 5%. Incomplete Kawasaki disease can be difficult to diagnose because some classical features may be absent, therefore clinicians must maintain a high level of suspicion in children with prolonged fever and elevated inflammatory markers.

Conclusion

Persistent fever combined with mucocutaneous symptoms should raise suspicion for Kawasaki disease. Early recognition and treatment with intravenous immunoglobulin are essential to prevent serious cardiovascular complications and ensure good clinical outcomes in affected children.

References

1. American Academy of Pediatrics. Red Book: Report of the Committee on Infectious Diseases.

2. McCrindle BW et al. Diagnosis, Treatment, and Long-Term Management of Kawasaki Disease.

3. Nelson Textbook of Pediatrics, 21st Edition.

4. World Health Organization Pediatric Guidelines.