My Grandson Who Is 5 1/2 Has Been Told By

My grandson who is 5 1/2 has been told by the doctor he has hands, feet, and mouth virus. That we can deal with but he also has swelling and redness around both nipple areas. The doctors at Childrens Hospital didn't know what it is at this time. Do you have any thoughts on if this could also be the virus? Thankyou.