Hello dear...

The differential diagnosis of a pimple or a sore on the inner buttocks cheek might be:

1. Acne- due to inflamed or infected sebaceous glands in the skin.
2. Boil/ Folliculitis- caused by the infection of a hair follicle
3. Herpes genitalis
4. Ingrown hair- condition where the hair curls back or grows sideways into the skin.
5. Cyst/ abscess
6. Insect bite- eg Bedbug bite
7. Pressure sores- most probable cause based on age & physiological status
8. Contact dermatitis

And as you have mentioned that the sore is painless...the infective causes can be ruled out.

So...it will be better to consult a Dermatologist to find out the exact cause & further management.

Wishing a Good Health. Let me know if I need to clarify further.

Thanks & take care.

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Hello dear, thanks for your revert.

The presence of diabetic status makes an individual prone to infections/boils which tend to show characteristics of delayed healing...though the recurrence of a 30 yr old healed infection is rare...unless there is a fresh episode of trauma or infection over the same site.

Therefore, it will be better to get the blood sugar levels checked once.

If it reveals anything significant...then steps should be taken to control the blood sugar levels first.

Otherwise, the boil can be taken care of by antibiotics, analgesics & antihistamines under the guidance of a Dermatologist.

I hope this answers you to an extent. Please feel free to ask any further doubt.

Wishing a good health.

Thank You.

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