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For further information, see CMDT Part 15-40: Hemorrhoids

Key Features

Essentials of Diagnosis

  • Bright red blood per rectum

  • Protrusion of tissue from anus, with discomfort

  • Characteristic findings on external anal inspection and anoscopy

General Considerations

  • Internal hemorrhoids are subepithelial vascular cushions consisting of connective tissue, smooth muscle fibers, and arteriovenous communications between terminal branches of the superior rectal artery and rectal veins

  • External hemorrhoids arise from the inferior hemorrhoidal veins located below the dentate line and are covered with squamous epithelium of the anal canal or perianal region

  • Causes include

    • Straining at stool

    • Constipation

    • Prolonged sitting

    • Pregnancy

    • Obesity

    • Low-fiber diet

Clinical Findings

Symptoms and Signs

  • Bright red blood per rectum

    • Streaks of blood visible on toilet paper or stool, or bright red blood that drips

    • Uncommonly, severe and prolonged enough to cause anemia

  • Mucoid discharge

  • Internal hemorrhoids

    • May gradually enlarge and protrude

    • Prolapsed hemorrhoids appear as protuberant purple nodules covered by mucosa

    • Discomfort and pain are unusual, occurring only when there is extensive inflammation and thrombosis of irreducible tissue

  • External hemorrhoids

    • Readily visible on perianal inspection or may protrude through the anus with gentle straining

    • Usually asymptomatic, though may interfere with perianal hygiene

    • Acute thrombosis causes severe pain

    • Prolapsed hemorrhoids are visible as protuberant purple nodules covered by mucosa

    • The perianal region should also be examined for other signs of disease, such as fistulas, fissures, skin tags, condyloma, anal cancer, or dermatitis

  • Thrombosed external hemorrhoid

    • Appears as an exquisitely painful, tense and bluish perianal nodule covered with skin that may be up to several centimeters in size

  • Pain is most severe within the first few hours but gradually eases over 2–3 days as edema subsides

Differential Diagnosis

  • Rectal prolapse

  • Anal fissure

  • Anal skin tag

  • Perianal fistula or abscess, eg, Crohn disease

  • Infectious proctitis, eg, gonorrhea

  • Anogenital warts (condyloma acuminata)

  • Perianal pruritus

  • Proctalgia fugax or levator ani syndrome

  • Lower gastrointestinal bleeding due to other cause, eg, diverticulosis, polyps, colorectal cancer


Diagnostic Procedures

  • Anoscopy: visualization of internal hemorrhoids

  • Grading

    • I: No prolapse

    • II: Prolapse with defecation; spontaneously reduces

    • III: Prolapse with defecation or other times; requires manual reduction

    • IV: Permanently prolapsed mucosal tissue; visible externally



  • Surgical excision (hemorrhoidectomy) for patients with grade IV hemorrhoids with persistent bleeding or discomfort

Therapeutic Procedures

  • Patients with stages I–III hemorrhoids and recurrent bleeding despite conservative measures may be treated without anesthesia with

    • Injection sclerotherapy

    • Rubber band ligation (preferred due to ease of use and high efficacy rate)

    • Application of electrocoagulation (bipolar cautery or infrared photocoagulation)

Conservative measures

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