I have the same type of symptoms: blister like lesion and then scabs over and the skin peels around the spot he has a high white blood count.
but also in clusters only on my fingers.
doctors treated me with a concentrated cortisone, it worked but i comes back randomly.
it's a mild side affect from a severs case of staff infection when i was younger like 7yrs or so.
no one else in my family has it, at least to my knowledge. and is not contagious i think but keeping hands clean and MILD SOAP is a good way to prevent it. but my finger tips are scared like vary soft and sensitive to touch, while looking wrinkly like an elephant but not as bad as that just to give you an idea.
I've had outbreaks of this rash for over a decade( I'm in my early 20's), also i have vary oily skin so it's easier for the rash to pop up and spread.
this is just a skin rash don't worry about it to much i hope this helps you some.

