Suggest Treatment For Clear Yellow Fluid Discharge From Crack Of Buttocks

My husband's butt crack has been raw and cracking for a couple of weeks. Now, he is starting to develop bumps that ooze a clear yellowish fluid. It is so bad that when he sits down, he leaves a wet spot on the chair. We've been putting desenex powder on the area, and it seemed to be getting better; but it is much worse tonight. Any suggestions?