| Subject | Contents |
| Definition | A diagnostic procedure in which a small piece of rectal tissue is removed for examination. |
| Alternative Names | Biopsy - rectum |
| How the test is performed | A rectal biopsy is usually part of anoscopy or sigmoidoscopy . First, a digital rectal examination is performed. The doctor inserts a lubricated, gloved finger into the rectum to determine if anything will block the insertion of the anoscope. A lubricated anoscope (or sometimes, a rectal speculum or proctoscope) is then inserted, which will cause some pressure. If a biopsy must be taken, it can be done through any of these scopes. The scope is a short tube with a light attached; it enlarges the rectum to allow the doctor to view the entire anal canal. Anesthetic is introduced through the anoscope, then biopsy forceps, a cytology brush, culture swab, or suction catheter is introduced through the anoscope to take a sample. Afterward, the scope is slowly removed. |
| How to prepare for the test | You will need to defecate before the procedure and a laxative, enema, or other preparation may be administered. |
| How the test will feel | There will be some pressure during the procedure, and you may feel an urge to defecate. A small amount of cramping sometimes occurs as the anoscope is inserted, but there should be no pain. |
| Why the test is performed | A rectal biopsy is used to determine the cause of abnormal growths found on anoscopy , sigmoidoscopy , or other tests. It can also be used to confirm the diagnosis of amyloidosis . |
| Normal Values | The anus appears normal in size, color, and shape. There should be no evidence of bleeding , polyps, hemorrhoids , or other abnormalities. On microscopic examination of biopsy tissue, no abnormalities should be noted. |
| What abnormal results mean | This test is one of the more common means to confirm amyloidosis . It also determines the specific causes of abnormal conditions of the rectum, such as squamous cell tumors of the rectum. Other findings could include colorectal polyps , abscesses , inflammation, infection, or hemorrhoids . Additional conditions under which the test may be performed:Hirschsprung's disease |
| What the risks are | There is some risk of bleeding and mild pain after the biopsy . Occasionally, patients have problems with urinary retention after rectal biopsy. |
| Special considerations | Not applicable. |
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