Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain it seems that small red irritated bumps at the rear end of the buttcrack can be due to
Contact Dermatitis that is due to
allergic reaction to any soap, detergent, chemical cosmetic etc..
It can also be due to hair
follicle infection or folliculitis due to overgrowth of bacteria which is more probable to occur in moisture..
It is not looking like Psoriasis as Psoriasis is in the form of scaly patches..
I would suggest you to
consult a Proctologist and get evaluated and a thorough clinical evaluation and investigations like microscopic examination of the scrapings from the bumps can help in diagnosis..
In case if there allergic reaction anti allergics like Benadryl and topical application of
hydrocortisone ointment can help..
In case of folliculitis antibiotics oral as well as topical can help..
Also keep the area dry and clean and wear cotton undergarments..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora..