Kawasaki Disease with Rare Presentation Masquerading as Severe Infection in Children: A 10-year Retrospective Review in a Tertiary Hospital in Hong Kong SAR

Abstract

Kawasaki disease (KD) with uncommon presentations can lead to diagnostic confusion mimicking severe infections: particularly KD shock syndrome (KDSS) mimicking toxic shock syndrome; and retropharyngeal edema (RPE) mimicking retropharyngeal neck abscess according to our local experience. High vigilance is needed for early diagnosis and timely treatment to minimize unnecessary operations and development of complications. A 10-year (2007-2016) retrospective review was performed for KD presented with features of KDSS/RPE. 120 KD cases were recruited. M:F was 1.2: 1, age 3.5 months to 12 years old. Sixteen had RPE mimicking neck abscess (13.3%) presenting as fever with neck complaints: swelling, pain or refusal to rotation/extension. None of them fulfilled sufficient diagnostic criteria for KD initially, some even with absent KD signs. They responded poorly to administration of antibiotics. Neck X-ray showed thickened retropharyngeal space suspicious of abscess. Computed tomography (CT) showed retropharyngeal fluid collection with no definite rim-enhancement. One case in doubt of early abscess underwent fine needle aspiration yielding 1.5ml necrotic material, sterile for bacterial culture. Signs of KD emerged as clinical course progressed, and all patients responded well to treatment with immunoglobulin (IVIG) and aspirin. Four presented as KDSS mimicking toxic shock (3.3%) with systolic hypotension requiring inotropic support and had ventricular dysfunction, mitral regurgitation on echocardiogram. Three had coronary ectasia on presentation. All were IVIG resistant and had severe hypoalbuminemia, probably contributing to shock. Two required pulse methylprednisolone and two responded to second dose IVIG.