The purpose of the digital rectal examination is to identify lesions within the rectum and the prostate. It is the most widely used and oldest technique for the detection of prostate cancer and is used in screening for colon cancer and for the detection of rectal polyps.
Description
Usually the patient is positioned on the left side with the knees close to the chest. Sometimes the patient is asked to stand up and lean over the examination table. For women, sometimes this examination is part of the routine gynecological exam, and it may be done in a different manner than described here.
During the examination, the health care practitioner examines the anus and the surrounding skin for hemorrhoids, tags, fissures and abscesses. After lubricating the gloved finger and anus, the examiner gently slides the finger into the anus and follows the contours of the rectum. The examiner notes the tone of the anus and feels the walls and the edges for texture, tenderness and masses as far as the examining finger can reach. The examiner evaluates the prostate for nodules and tenderness. Stool on the finger should be examined for blood, color, texture and tested for fecal occult blood.
The examination takes less than two minutes and can be uncomfortable when the patient is not relaxed or is anxious. Occasionally, when the DRE is performed on a man the penis may become erect. A gentle reminder and reassurance helps to relieve the embarrassment associated with the unexpected erection.
Preparation
The patient must be carefully positioned and the doctor should take care to explain the examination to the patient and to explain to the patient what to expect. The digital rectal examination may be uncomfortable and embarrassing. Much of the discomfort can be reduced by an understanding, unhurried and gentle examiner.
Precautions
When there are infections of the anus and of the rectum, the digital rectal examination should not be performed. Manipulation of the anal and rectal tissues increases the risk of infection and of bleeding.
Results
In the normal anus and rectum, there are no hemorrhoids or bleeding about the anus. The anal tone is not loose. The rectum is smooth and non-tender. No masses should be palpated, or felt.
The digital rectal examination is helpful in identifying areas of peritonitis or tender areas that can be felt through the wall of the rectum. It is used to identify perineal disease or deformity, abnormal location of the anus, rectal
prolapse and atrophy of the gluteal muscle. Digital examination can detect a stenosis (or narrowing) of the anal canal, assess the tone and strength of the anal muscles or detect the presence of a rectal mass or fecal impaction.
Any masses, including hard stool, blood or tenderness is considered abnormal. Cancer masses may be flattened, nodular, cauliflower-like or ring-shaped. Polyps can be felt, but must be visualized using anoscopy or flexible sigmoidoscopy to be distinguished from other lesions, such as internal hemorrhoids or malignant growths. Hard masses of feces may be felt and may be removed.
Aftercare
Aftercare of the digital rectal examination is minimal. It requires removal of the lubricating jelly residue from around the anus. The lubricating jelly dissolves easily in water and may be washed off in bathing after the examination. It can be removed with toilet paper immediately after the examination.
