Answer:
(medium-vessel vasculitis) Kawasaki disease.
Explanation:
 The most common such condition is such that occurs at childhood I.e. Kawasaki disease. It is a necrotizing vasculitis that is characterized be a predilection for the coronary arteries.
 
        
             
        
        
        
He needs to improve his endurance
        
             
        
        
        
When a baby is first born, the skin is a dark red to purple color. As the baby starts to breathe air, the color changes to red. This redness normally starts to fade in the first day. A baby's hands and feet may stay bluish in color for several days.