Other Tests

Most patients with obvious pathology will not require further imaging, although if there is a doubt about diagnosis or extent of disease then imaging is required.

Specialist investigations that could be carried out in the ED include:

• Endoanal ultrasound scan, for looking at sphincters and identifying occult sepsis [6]
• MRI, for looking for occult sepsis and delineating tracts of fistulae [6]
• Examination under anaesthetic, if unable to examine while awake due to pain or spasm
• Sigmoidoscopy/colonoscopy/barium enema, to exclude colorectal malignancy as a cause for symptoms
• Anorectal physiology, if soiling

Learning bite

Any patient aged 40 years or more with PR bleeding suspected to be haemorrhoidal also warrants further investigation to exclude colorectal malignancy.