Dermatologist's case (4)
I believe the answer is:
acne
'dermatologist's case' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for acne that I've seen before include "Pimply ailment of adolescnce" , "sort of disease" , "Spotty coverage" , "Skin complaint" , "Skin affliction" .)