What are the clinical characteristics of cervical lymphadenopathy in a child with suspected Kawasaki disease?

Cervical Lymphadenopathy in Kawasaki Disease: Clinical Characteristics

In Kawasaki disease, cervical lymphadenopathy typically presents as unilateral swelling of lymph nodes ≥1.5 cm in diameter, confined to the anterior cervical triangle, and is the least common of the principal diagnostic features. 1

Physical Examination Findings

Size and Location

• Lymph nodes are ≥1.5 cm in diameter, which is the diagnostic threshold for Kawasaki disease 1
• Swelling is usually unilateral (present in 95% of cases when lymphadenopathy occurs) 1
• Confined to the anterior cervical triangle rather than diffuse or generalized 1

Palpation Characteristics

• Multiple lymph nodes are enlarged rather than a single node 1
• Nodes are typically not tender in nontuberculous mycobacterial infections, which can be confused with Kawasaki disease 2
• The lymphadenopathy is non-suppurative (does not form pus) 1

Key Distinguishing Features from Bacterial Lymphadenitis

What Makes It Different

• Multiple enlarged nodes are present in Kawasaki disease, whereas bacterial lymphadenitis typically presents with a single node with a hypoechoic core on ultrasound 1
• Retropharyngeal edema or phlegmon is common in Kawasaki disease, which can be visualized on imaging studies 1
• Deep neck inflammation may extend to parapharyngeal and retropharyngeal spaces 1

Critical Diagnostic Pitfall

• In a small subset of patients, lymph node findings may be the most notable and sometimes only initial clinical finding, prompting misdiagnosis as bacterial lymphadenitis and significantly delaying Kawasaki disease diagnosis 1
• Unresponsiveness to antibiotics is a key clue—when fever persists despite antibiotic treatment for presumed bacterial adenitis, Kawasaki disease should be strongly considered 3, 4, 5
• 42-52% of Kawasaki disease patients with cervical lymphadenopathy are initially misdiagnosed as having bacterial cervical adenitis 5

Clinical Context and Timing

Presentation Pattern

• Cervical lymphadenopathy is the least common of the five principal clinical features of Kawasaki disease 1
• Only 24% of Kawasaki disease patients present with cervical lymphadenopathy 6
• Fever persists, and other typical Kawasaki disease features (rash, conjunctival injection) will follow after the initial lymph node presentation 1

Age-Related Considerations

• School-aged children with Kawasaki disease have a notably high incidence (100% in one series) of cervical lymphadenopathy as a presenting feature 3
• In these older children, unilateral neck mass mimicking acute suppurative infection was the initial presentation in 90% of cases 3
• The mean interval between disease onset and diagnosis was 9.9 days when lymphadenopathy was the predominant feature, indicating significant diagnostic delay 3

Imaging Characteristics

Ultrasound and Advanced Imaging

• Ultrasound and CT can help differentiate Kawasaki disease lymphadenopathy from bacterial lymphadenitis 1
• MRI may reveal retropharyngeal inflammation and infiltration of parapharyngeal and retropharyngeal spaces 4
• Look for multiple enlarged nodes with retropharyngeal edema or phlegmon rather than a single hypoechoic node 1

Clinical Significance

When to Suspect Kawasaki Disease

• Any child with unilateral cervical lymphadenopathy ≥1.5 cm, prolonged fever (≥5 days), and failure to respond to antibiotics should be evaluated for Kawasaki disease 1, 3, 5
• Even if other principal clinical features are not initially present, maintain high suspicion as they typically develop sequentially 1
• The presence of exudative pharyngitis or a single suppurative node should prompt consideration of bacterial infection rather than Kawasaki disease 1

High-Risk Scenario

• School-aged children presenting with cervical lymphadenopathy as the dominant feature have a 70% incidence of coronary artery abnormalities, making early recognition critical 3