Do we have a less severe form of Kawasaki disease or is it the gammaglobulin effect?

This study was undertaken to evaluate the incidence of coronary artery aneurysms (CAA) in Kawasaki disease (KD). We reviewed the clinical and echocardiographic findings of 135 children who presented to our center with KD between December 1986 and December 1997. The age of onset ranged between 3months to 13 years (median 2 years). The male to female ratio was 1.54:1. All patients received intravenous Gammaglobulin (IVGG) during the acute stage. The echocardiogram, which was done between 2-3 weeks of the onset of fever, was normal in 106 patients (78.5%). Follow-up studies over a period of 6 months to 1 year remained normal. Minimal right or left coronary artery wall ectasia without dilatation or aneurysm formation was seen in 16 (11.85%). Follow-up of these patients showed disappearance of these changes over 6 weeks to 6 months. One patient (0.74%) had generalised dilatation of all the coronary arteries during the acute stage. This has normalized over a period of 9 months. A total of 10 (7.4%) had CAA during the acute stage. On follow-up of 8 of these patients for an average 3 months to 1.5 years all CAA regressed completely. One patient had residual Giant CAA after 1 year follow-up. One patient with CAA was lost to follow-up. One patient (0.74%) had pericardial effusion and another one (0.74%) had mitral incompetence during the acute stage only, both had no coronary involvement. None of our patients had cardiac failure, arrhythmia, myocardial infarction or death. We conclude that coronary artery changes due to KD are less common and less severe in our patients than those seen in other studies. We speculate that this can be related partly to the early administration of IVGG. The difference in incidence of CAA secondary to KD among different racial groups warrants more detailed genetic studies.