The causes of small stomach pain and anal swelling in patients may be the following: 1. Inflammatory bladder lesions: It may be due to some inflammatory bladder lesions, such as cystitis, which can cause pain in the perineal area, and painful stimulation can lead to anal swelling. 2. Gynecological inflammation: It may be due to some gynecological inflammation, such as adnexitis, and when adnexitis is heavy, it will lead to pelvic The pelvic fluid will stimulate the anal area, causing anal swelling and discomfort. 3, rectal lesions: may be due to some lesions of the rectum, can be rectal inflammation, can be rectal tumors, can also be caused by hemorrhoids, especially when the hemorrhoids combined with infection is more likely to appear. Patients found small stomach pain, anal swelling, the specific reasons recommended to the regular specialist hospital to find a professional physician consultation, consultation.