###Human: What has caused redness and tenderness in nipple with a bump under skin? ###Assistant: Hi. It looks like erysipelas, that is called the superficial skin infection. It would be helpful if you have had any recent laboratory investigations, complete blood count analysis ESR CRP that would be very helpful. I will advise you to apply Mupirocin ointment twice daily on the nipple so that will control the current infection from spreading anywhere. For pain, take Tylenol. If you need any further information, please write me back and at the same time I would also like to know about your medical history and surgical history. If you are a smoker or have a social history as well.