Hello I appreciate your concern Looking at your description this could be due to infection of the foreskin may be due to foleys catheter or diaper I would like further information to guide you better Why he has been catheterised? If possible upload a photograph? I would advise him to follow strict aseptic precautions He should wash and clean the site with an antiseptic solutions or antibiotics ointment Neosporin powder can be sprinkled upon the clean site Prolonged catheterisation and diaper both can cause to infection or inflammation of the foreskin as well as whole of the genital and perianal region Hope this answers your question please feel free to ask for more assistance, I will be happy to help you Best wishes