Anal, Rectal - Perianal abscess, Anal fissure, Anal fistula, Hemorrhoids, Pruritis ani, Anal neoplasm, Solitary rectal ulcer

Question 1

Perianal abscess
-what is it
-presentation
-causes
-investigations
-management
-associated conditions

Answer 1

Pus tracked from tissue around anal sphincter => collects in subcut tissue as abscess

Anal pain, worse on sitting
Hard tissue
May have discharge, systemic infection

Ecoli - gut flora
Saureus - spread from skin

Inspection and DRE

I+D under LA - wound packed/left open
ABx - if systemic upset

IBDs
DM
Malignancy

Question 2

Anal fissure
-what is it
-risk factors
-presentation
-management

Answer 2

Tears of distal anal canal lining
-U6wks - acute
-6wks+ - chronic

Constipation
IBD
STIs - HIV, syphilis, herpes

Painful, bright red rectal bleeding
Skin tag
Majority found on posterior midline
-any other location => think about Crohns

Acute
-Soften stool - high fibre, high fluids, bulk forming laxative
-lubricants before passing stool - vaseline
-TOP anaesthetics
-analgesia

Chronic
-Acute management + top GTN
GTN not effective after 8wks => 2ndary referral for sphincterotomy or botulinum toxin

Question 3

Hemorrhoids
-what is it
-types
-grading
-presentation
-management
-presentation and management of acutely thrombosed external hemorrhoids

Answer 3

Hemorrhoidal tissue - contribute to anal continence
-3, 7, 11oclock
But become symptomatic when enlarged and congested

External
-below dentate line
-prone to thrombosis, can be painful

Internal
-above dentate line
-generally not painful

Grade I - no prolapse out of anal canal
Grade II - prolapse on defecation with spontaneous reduction
Grade III - manual reduction needed
Grade IV - cannot be manually reduced

PAINLESS rectal bleeding
unless thrombosed
Itch

Stool softening - increase fibre and fluids
Rubber band ligation
Hemorrhoidectomy

Acutely thrombosed external
-significant pain
-purple, edematous, tender subcut mass

U72hrs - refer for excision?
72hrs+ - stool softeners, ice packs, analgesia
Settles in 10 days

Question 4

Anal fistula
-what is it
-associations
-presentation
-investigations
-management

Answer 4

Inflammatory tract between anal canal and perianal skin

Discharge from anus

MRI - classify between simple (low fistula) and complex (passes through/above muscle layers)

Symptomatic - PO metronidazole
-infliximab - can also be considered
Draining seton if complex
-keep it open prevent premature skin closure

Question 5

Pruritis ani
-associations

Answer 5

Chidren - worms
Adults - idiopathic, related to other causes like hemorrhoids

Question 6

Anal neoplasm

Answer 6

Anal - SCC
Rectum - Adenocarcinoma

Question 7

Solitary rectal ulcer

Answer 7

Chronic straining and constipation
-mucosal thickening
-lamina propria replaced with collagen and smooth muscle