Teenager with new brown freckles in his armpits

Should you be concerned by this new freckling which has developed during puberty?
Teenager with new brown freckles in his armpits

A teenager is brought to your surgery by his mother who mentioned that he has a number of brown freckles on his skin, which she thinks have been there since he was much younger. However, since puberty he has developed further freckles in his armpits. On examination, you notice that he has some freckling in the axillae and also the skin folds in his groin. He looks otherwise quite fit and healthy. 

Picture's credit: DermNet NZ, CC BY-NC-ND 3.0 NZ



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