Onychomadesis is a periodic idiopathic shedding of the nails beginning at the proximal end, possibly caused by the temporary arrest of the function of the nail matrix. One cause in children is hand foot and mouth disease. This generally resolves without complication. Another cause of onychomadesis in children is Kawasaki disease.
Figure: Four Cases of Onychomadesis after Hand-Foot-Mouth Disease
Figure: Onychomadesis and Kawasaki disease