anal fissures

Question 1

what are risk factors for anal fissures?

Answer 1

constipation
inflammatory bowel disease (crohns)
sexually transmitted infections e.g. HIV, syphilis, herpes

Question 2

what is the best imaging for anal fissure?

Answer 2

MRI

Question 3

what are features of anal fistulas?

Answer 3

Patients typically present with anal discharge and discomfort.
On physical examination the external fistula opening may be visible.
It is important to perform a digital rectal examination to check for the location of the internal fistula opening.

Question 4

where are most anal fissures found, and what should you think if they are not found here?

Answer 4

around 90% of anal fissures occur on the posterior midline.
if the fissures are found in alternative locations then other underlying causes should be considered e.g. Crohn’s disease

Question 5

what are features of anal fissures?

Answer 5

Patients typically present with severe anal pain or a tearing sensation on passing stools.

This can last up to hours after passing stool. Anal spasms are reported by 70% of patients.

PR bleeding is also common. This is typically bright red blood noticed on the stool/on the paper.

Question 6

what are the treatments for anal fissures?

Answer 6

first line treatments:
(within 1 week)

Treatment of constipation – laxatives/fibre in diet
Topical analgesics – lidocaine cream / jelly
Topical vasodilators e.g. nifedipine or nitroglycerine

Second line treatments:

• topical calcium channel blockers (diltiazem),
• oral nifedipine / diltiazem.

third line:
if topical GTN not effective after 8 weeks then consider sphinterotomy or botulin toxin

Question 7

what is the triad for a chronic fissure?

Answer 7

triad: Ulcer, sentinel pile, enlarged anal papillae

Question 8

what is the main cause of rectoanal fistulas?

Answer 8

rectoanal abcess

Question 9

when is a seton stitch used?

Answer 9

They are used in anal fistulae to keep them open and allow proper drainage before definitive repair.

Question 10

when would you do an endoscopy after anal bleeding?

Answer 10

if > 50

Question 11

what are risk factors for anal abscess

Answer 11

Any anorectal abscess can be caused by an underlying inflammatory bowel disorder, especially Crohn’s;
Diabetes mellitus is a risk factor due to its ability to affect wound healing;
Underlying malignancy can cause these abscesses as well as other anorectal lesions due to the risk of bowel perforation.