I read about a man with this condition in a book about candida. I don't know for sure that candida is the main culprit, but this is a symptom of dysbiosis. Many people believe that disease is genetic, but most of our immunity is in our internal ecosystem of microbes. They have a large degree of influence on gene expression as well. If you want to learn how to balance your microflora I recommend lifespa.com and the book The Prime (I forget the author).