Kawasaki disease complicated by mild encephalopathy with a reversible splenial lesion (MERS).

We reported four patients (2 to 10 years) with Kawasaki disease complicated by clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). All were treated with γ-globulin (2 to 6 g/kg) after the diagnosis of Kawasaki disease, the fever being alleviated between day 6 and 25. One of two patients exhibiting a poor response to γ-globulin had a cardiac aneurysm as a sequela. Their neurological manifestations (delirious behavior and drowsiness), laboratorial hyponatremia, and radiological abnormalities completely disappeared. It is important for pediatricians to acknowledge that MERS can be observed in patients with Kawasaki disease, especially in older children, and that they might be at high risk for cardiac abnormalities.