Hemorrhoids are dilated veins of the hemorrhoidal plexus in the lower rectum. Symptoms include irritation and bleeding. Thrombosed hemorrhoids are painful. Diagnosis is by inspection or anoscopy. Treatment is symptomatic or with endoscopic banding, injection sclerotherapy, or sometimes surgery.
(See also the American Gastroenterological Association's technical review and medical position statement on diagnosis and treatment of hemorrhoids.)
Increased pressure in the veins of the anorectal area leads to hemorrhoids. This pressure may result from pregnancy, frequent heavy lifting, or repeated straining during defecation (eg, due to constipation). Hemorrhoids may be external or internal. In a few people, rectal varices result from increased blood pressure in the portal vein, and these are distinct from hemorrhoids.
External hemorrhoids are located below the dentate line and are covered by squamous epithelium. Internal hemorrhoids are located above the dentate line and are lined by rectal mucosa. Hemorrhoids typically occur in the right anterior, right posterior, and left lateral zones. They occur in adults and children.
Symptoms and Signs
Hemorrhoids are often asymptomatic, or they may simply protrude. Pruritus ani is not commonly caused by hemorrhoids unless they are significantly prolapsed.
External hemorrhoids may become thrombosed, resulting in a painful, purplish swelling. Rarely, they ulcerate and cause minor bleeding. Cleansing the anal region may be difficult.
Internal hemorrhoids typically manifest with bleeding after defecation; blood is noted on toilet tissue and sometimes in the toilet bowl. Internal hemorrhoids may be uncomfortable but are not as painful as thrombosed external hemorrhoids. Internal hemorrhoids sometimes cause mucus discharge and a sensation of incomplete evacuation.
Strangulated hemorrhoids occur when protrusion and constriction occlude the blood supply. They cause pain that is occasionally followed by necrosis and ulceration.
Most painful hemorrhoids, thrombosed, ulcerated or not, are seen on inspection of the anus and rectum. Anoscopy is essential in evaluating painless or bleeding hemorrhoids. Rectal bleeding should be attributed to hemorrhoids only after more serious conditions are excluded (ie, by sigmoidoscopy or colonoscopy).
Symptomatic treatment is usually all that is needed. It is accomplished with stool softeners (eg, docusate, psyllium), warm sitz baths (ie, sitting in a tub of tolerably hot water for 10 min) after each bowel movement and as needed, anesthetic ointments containing lidocaine, or witch hazel (hamamelis) compresses (which soothe by an unknown mechanism). Pain caused by a thrombosed external hemorrhoid can be treated with NSAIDs. Infrequently, simple excision of the external hemorrhoid is done, which may relieve pain rapidly; after infiltration with 1% lidocaine, the thrombosed portion of the hemorrhoid is excised, and the defect is closed with an absorbable suture.
Bleeding internal hemorrhoids can be treated by injection sclerotherapy with 5% phenol in vegetable oil. Bleeding should cease at least temporarily.
Rubber band ligation is used for larger, prolapsing internal hemorrhoids or those that do not respond to conservative management. With mixed internal and external hemorrhoids, only the internal component should be rubber band ligated. The internal hemorrhoid is grasped and withdrawn through a stretched ½-cm diameter band, which is released to ligate the hemorrhoid, resulting in its necrosis and sloughing. Typically, one hemorrhoid is ligated every 2 wk; 3 to 6 treatments may be required. Sometimes, multiple hemorrhoids can be ligated at a single visit.
Infrared photocoagulation is useful for ablating nonprolapsing, bleeding internal hemorrhoids, hemorrhoids that cannot be rubber band ligated because of pain sensitivity, or hemorrhoids that are not cured with rubber band ligation. Doppler-guided hemorrhoid artery ligation, in which a rectal ultrasound probe is used to identify vessels for suture ligation, appears promising. Laser destruction, cryotherapy, and various types of electrodestruction are of unproven efficacy.
Surgical hemorrhoidectomy is required for patients who do not respond to other forms of therapy. Significant postoperative pain is common, as is urinary retention and constipation. Stapled hemorrhoidopexy is an alternative procedure for circumferential hemorrhoids but its advantages and the indications have yet to be defined.
Last full review/revision July 2012 by Parswa Ansari, MD
Content last modified November 2013