Digital Rectal Exam

The digital rectal exam (DRE) is a form of physical examination used by physicians to evaluate the anal and rectal regions manually. "Digital" refers to the use of the examiner's digit, or finger, to perform the exam. Essentially, the lubricated finger is inserted in the anus and used to feel for any abnormalities including masses in or around the anus. The tone, or strength, of the anal sphincter, the encircling muscle that closes the anus, is also examined.

The digital rectal exam is part of any complete physical examination, particularly in older men. The purpose of the exam is to help identify diseases in the area to aid in their diagnosis. This can include screening for anal masses which may be anal cancer. However, the DRE is also commonly used to screen for prostate cancer as well. In fact, there are many other diseases that can be examined by this means.

The prostate gland in men, although not part of the anus or rectum, lies immediately adjacent to the anus. Therefore, the gland can be felt quite easily through the front wall of the anus. The examiner can therefore examine the prostate gland for overall size, consistence and any irregularity including masses in the gland. Therefore, the DRE is a common screening test done to attempt to identify prostate tumors. If abnormal masses are felt, a biopsy of the prostate gland can even be taken through the wall of the anus.

The DRE may also be employed to examine other diseases of the region including hemorrhoids, anal warts and anal abcesses. The fecal material obtained on the examiner's finger can also be used to test for occult fecal blood, which may indicate disease elsewhere in the digestive tract (such as bleeding ulcers, tumors, etc.). Finally, this examination of the anus, in particular examination of the anal sphincter muscle, is also a part of the neurological examination as certain pathologies of the spinal cord and spinal nerves can cause dysfunction of the sphincter.

The digital rectal exam should not be confused with anoscopy which utilizes a special speculum called an anoscope or proctoscope to visually examine the interior of the anus.