What Is a Digital Rectal Exam?
A digital rectal examination (DRE) is a simple procedure doctors use to examine the lower rectum and other internal organs. DRE is done for a number of reasons. For instance, it’s a quick, easy way to check the health of a man’s prostate gland. Conditions like enlarged prostate (benign prostatic hyperplasia, or BPH) and prostate cancer can be detected by DRE.
The prostate is a walnut-sized organ that supplies some of the semen released during male ejaculation. This fluid nourishes and protects sperm released into the vagina during intercourse. In combination with the prostate specific antigen (PSA) blood test, DRE can be used to monitor any changes in the health of the prostate.
Why a Digital Rectal Exam Is Performed
A digital rectal exam may be used to:
- diagnose rectal tumors
- obtain feces for the fecal occult blood test (used as a screening for gastrointestinal bleeding or colon cancer)
- prepare you for colonoscopy (a procedure to examine the small bowel) or proctoscopy (a procedure used to examine the anus, rectum, or colon
- assess the function of the anal sphincter in cases of fecal incontinence
- assess the extent of hemorrhoids (swollen veins in the anus)
- help diagnose appendicitis (inflammation of the appendix)
- check the status of pelvic organs, especially among women
How the Test Is Performed
A DRE may also be part of a routine gynecological exam for women. Some doctors do not believe the DRE yields enough clinically useful information, however, and may skip this step during gynecological exams.
To perform a DRE, the doctor gently inserts a gloved, lubricated finger into the patient’s anus. The doctor uses his or her finger to feel for any abnormalities. For example, an enlarged prostate may be detected as a bulge behind the rectum wall.
Prostate cancer may be detectable as bumps on the normally smooth surface of the prostate. The doctor must apply firm pressure on the prostate. Men with enlarged or inflamed prostates may feel pain or the urge to urinate.
The DRE is part of a routine physical examination for both men and women. During a gynecological exam, DRE may be used to help doctors check the health of pelvic organs. Most women and many men feel only minor discomfort during the procedure. People with hemorrhoids or anal fissures may experience a small amount of bleeding.
The DRE is not suitable for directly detecting colon cancer because only a small portion of the lower colon may be accessed by DRE. DRE may be used, however, to obtain a stool sample. Stool samples may be used to conduct a fecal occult blood test (FOBT). A positive result, meaning that blood is present in the stool, may indicate colon cancer or other problems. Such blood is not visible to the naked eye.
Preparing for the Test
You will be asked to disrobe and put on a hospital gown. You will probably be asked to lie on your side. Alternative positions include squatting on the exam table, bending over the table, or lying on the table with your feet in raised stirrups. Most doctors choose the position that is likely to be most comfortable for the patient.
The doctor will ask you to attempt to relax as he or she gently inserts a gloved and lubricated finger into your anus. The doctor will probe the lower rectum for a few seconds to a minute or longer. The doctor may press down on your lower abdomen during the exam.
After a DRE
The DRE is relatively safe and easy to perform. No equipment is needed, other than examination gloves and sterile lubricant. In some cases of benign prostatic hyperplasia, the doctor may be unable to reach a definitive diagnosis based on the DRE alone. In these instances, he or she may recommend a procedure called tranrectal ultrasound (TRUS). In this procedure, an ultrasound wand is inserted into the rectum. The wand produces sound waves and a computer converts the sound waves into images. Doctors use these images to diagnose various diseases of the prostate.