Abnormally enlarged vascular mucosal cushions in the anal canal

Aetiology

Risk factors

• Excessive straining (from chronic constipation)
• Increasing age
• Raised intra-abdominal pressure (e.g. pregnancy, chronic cough, ascites)

Pathophysiology

• The classical position of haemorrhoids corresponds to the branches of the superior haemorrhoidal artery - 3, 7 and 11 o’clock
• Internal haemorrhoids: found above the dentate line, located inside the back passage where the rectum joints the anus
  • Graded 1st to 4th degree
• External haemorrhoids: form below the dentate line, found at the anal opening and are covered by skin

Clinical features

Symptoms

• Painless bright red rectal bleeding
• Perianal itchiness
• No change in bowel habit, no weight loss or other associated symptoms

Signs

• Examination will usually be normal unless the haemorrhoids have prolapsed

Investigations

• PR exam
• Proctoscopy