Perianal abscesses and fistulae

Question 1

What is a perianal abscess

Answer 1

infection of soft tissue resulting in accumulation of pus within its walled off cavity

Question 2

What are the 3 main sites of perianal abscesses

Answer 2

perianal - close proximity to the anal verge

intersphincteric- in between internal and external sphincters

ischiorectal- lateral to sphincters and in the ischiorectal fossa

Question 3

How may a patient present

Answer 3

pain around anus- worse on sitting

hardened tissue in anal region

pus like discharge

can have signs of systemic infection if abscess is long standing

Question 4

What are risk factors

Answer 4

anal fistula
crohns
male
hard stools
21-40 years

Question 5

What are 1st investigations to order

Answer 5

clinical examination

exam under anaesthetic - particulary for inter-sphinteric/supra-levator

Question 6

What investigations should be considered

Answer 6

WBC count - can be elevated

Serum glucose– may be elevated

Question 7

What is first line management for perianal abscess

Answer 7

incision and drainage

Question 8

What is management for fistulae

Answer 8

supportive
if secondary to crohn’s- drain acute sepsis with seton

Question 9

What should be considered if anal fistula is found

Answer 9

fistulotomy

Question 10

What additional treatment should be given and when should it be given

Answer 10

If elderly, immunocompromised,
cardiac valvular disease, diabetes, cellulitis

• give broad spectrum Abx with anaerobic and gram-negative coverage
• consider aminoglycosides for cellulitis