Thanks for writing in to us.
If its been there for 15 years with no significant problems then unlikely to be bacterial infection. If you say that its appearance is constant over years and no itching or pain and scaling, then even fungal infection
Under above situation, you may choose to ignore but be aware of the condition. Normal genital bacteria is unlikely to cause any problems. The 1% hydrocortisone
acetate cream is just fine but it has more of a placebo effect I guess.
I would suggest you maintain genital hygiene and not get worried about the area of redness
Hope this helps