In the past few months, at the age of 60, I have developed seriously thin skin on my arms (I remember my mother had this problem, but she was in her 80s). The other day I managed to poke a fingernail thru it. If I scratch an itch, I'm rewarded by a line of purple lesions. The discolorations appear to be exacerbated by exercise (I'm a serious gym rat and in great shape) and sometimes grow larger. At times they appear spontaneously without any trama that I can recall. They fade away in about a week. I still look really good in a cocktail dress, but not with purple blotches all over my arms. I do not take steroids or blood thinners, and my blood numbers are fine. What is going on? What can I do?