This sounds like something I had happen recently. I got lots of little pimples where my leg joins in and hits the side of the seat. I was riding the same saddle I always had - I think I just left shorts on too long and it was a *really* hot day.

I didn't take time off the bike (though I did put some antibiotic ointment on the pimples) and they turned in the red itchy raw bumps the next time I rode. They kept getting worse (even though I stopped riding b/c they hurt SO badly ), and I ended up going to the doc, who gave me a scrip for an ointment. It's an antifungal and something else. Basically, it will help anything from ringworm to allergic detmatitis. I used it for a week (and stayed off the bike per my doc's instructions), and the sores cleared up. However, then the top layer of skin in the area peeled (too many meds maybe) and I'm still having to be careful not to irritate the still tender skin when riding. I've started using a lube in that area - still experimenting on which one I like - to safeguard.

Odd (and very unpleasant) experience. Bottom line - keep an eye on those pimples!