Diagnosis For Recurrent Generalized Rashes In A Boy

This average wt, 1 and a half years old, normally developed boy is having recurrent papulonodular generalised rashes including palms and soles. Oral mucosa is spared. The rashes are mildly pruritic and began as pearly white vesicles and in due course converted to a hyperemic papulonodular form with umbilication. Further, in few days fades out leaving mild hyperemia marks. For last 2 to 3 months new crops erupted and older subsides and there is no benefit of steroids local and oral antihistaminics and antiallergics at all advised by various specialists. I found normal CBC, ESR, Na, K, Ca, P, Cr and ur r/m and c/s, IGG, IGA, IGM are normal but IGE is more than 2500 (n 100 to 300).

I have planned further investigations. So what's the diagnosis? Is it allergic or something else? What is the rash? The clue is umbilicated rashes with highly raised IGE.