Hi,

Thanks for your query.

Presence of soreness with yellow pus discharge is a sign of infection, most commonly bacterial infection.

The picture you sent also reveals signs of inflammation probably secondary to infection.

If you had involved in recent unprotected sexual activity, 'STD's - bacterial infections/viral with secondary bacterial infections' cannot be ruled out.

Other likely causes are rectal abscess or infected rectal sinus.

You will need to a per rectal examination and microscopy and culture test on the pus discharge. They will confirm the type of infection. A course of appropriate antibiotics should treat the condition. Rarely surgical incision and drainage is entailed.

I hope I have answered your query.

If you have any more queries, I will be able to answer them as well.

Regards

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