Steroids for Kawasaki disease: the devil is in the detail
- Correspondence to Professor Michael Levin, Department of Paediatrics, Imperial College London, Norfolk Place, London W2 1PG, UK;
- Received 11 September 2012
- Revised 11 September 2012
- Accepted 12 September 2012
- Published Online First 19 October 2012
In the 4 decades since the first description of Kawasaki disease (KD), the disorder has emerged as an important and common childhood condition with worldwide occurrence.1 KD is now recognised as the commonest cause of acquired heart disease in children in developed countries, and as an important cause of long term cardiac disease in adult life.2 The aetiology remains unknown but current thinking suggests that KD is an unusual inflammatory response to one or more as yet unidentified pathogen(s) occurring in genetically predisposed individuals.
Although the majority of patients with KD recover without long term consequences, the disorder is associated with vasculitis affecting the coronary arteries, and occasionally other muscular arteries, which results in coronary artery aneurysms (CAA) in over 20% of untreated patients.2 ,3 In all, 2%–3% of untreated patients die as a result of coronary artery thrombosis, myocardial infarction or, rarely, aneurysm rupture. Patients with giant (8 mm or more) CAA are at a long term risk of developing aneurysm thrombosis or coronary artery stenosis and myocardial infarction even years after the acute illness.2 In view of the frequency and severity of coronary artery complications, there has been intense interest in treatments to reduce the risk of CAA.
Intravenous immunoglobulin (IVIG) has been shown to reduce the risk of aneurysm formation to approximately 5%.4 ,5 Patients who do not respond to IVIG are at an increased risk of developing CAA and there is thus a need for additional treatments. Steroids are an effective treatment for other forms of vasculitis and their potential use in KD was considered soon after the disease was recognised. Early retrospective analyses of non-randomised treatment revealed that steroids were associated with increased risk of CAA.6 However, as the sickest patients were the most likely to have been given …