Perianal infection and fissures in ano Flashcards
Outline the signs and symptoms of patients with perianal infection/abscess?
Patient will present with painful swollen tissue in the perianal region.
The area will be red and inflamed and very tender.
It may discharge pus.
There may be signs of systemic illness, pyrexia, malaise.
What is the aetiology of perianal infection?
It is caused by blockage and infection of the anal glands which drain into the anal crypts.
What are the various types of perianal abscess?
Perianal abscess: the most common (60%) - caused by direct extension of sepsis in the intersphincteric plane next to the perianal skin.
Ischiorectal abscess: (20%) - results from extension of infection through the external sphincter into the ischiorectal space.
Intersphincteric abscess: (5%) - infection of the intersphincteric space.
Supralevator abscess: (4%) - produces horseshoe abscess track.
Define fistula in ano?
It is a chronic abnormal communication between the anal canal and skin (usually perianal skin)
It often occurs secondary to a perianal abscess (after it has been drained or has ruptured).
It should be suspected in the presence of recurrent abscesses.
Describe the management of perianal abscess?
Prompt surgical drainage and analgesia.
Antibiotics are only indicated if the patient has diabetes or other conditions which may predispose to infection.
Describe the management of fistula in ano?
Examination under anaesthetic, can MRI or endoanal USS
-If superficial and low then can be left open to heal by 2y intention
-If deep then can:
Inject with fibrin glue
Seton suture
Define a fissure in ano and describe the common sites?
A fissure in ano is a tear in the epithelium distal to the dentate line.
It is most commonly found at 12 o’clock* and 6 o’clock.
12 oclock = centrally at the top of the canal.
What are the signs and symptoms of a patient with an anal fissure?
- Fresh red blood in the stool on defecation.
- V.painful when defecating and pain continues for up to 2 hours.
- Pruritis ani
Signs: patient will try an resist you parting their buttocks due to the pain. You can see the tears. (90% at 6 o’clock)
Note: it should not cause blood on a PR you should investigate for a different cause.
In severe cases perform proctoscopy + sigmoidoscopy under anaesthesia to examine for anorectal disease.
How are anal fissures classified and what is the proposed aetiology?
Primary: no apparent cause.
Secondary:
- Constipation: a hard stool tears the anal mucosa as it is passed.
- Inflammatory bowel disease: ulceration as part of the inflammatory process.
- Sexually transmitted disease (syphilis)
- Anal malignancy.
Describe how anal fissures are managed?
Aim for regular soft stools:
-Adequate fluid intake
-High fibre diet
-Osmotic laxatives
- Pain relief:
Simple OTC analgesia
Warm baths
Chronic:
- Topical GTN can relax anal tone and improve pain (diltiazem preferred as doesn’t give headache, GTN does)
- Topical local anaesthetic for extreme pain.
- Sphincterotomy
Name some conditions associated with fistulas-in-ano
TB, Crohn’s, diverticular disease, rectal carcinoma, immunocompromised patients (HIV)
What is a Pilonidal sinus?
- Obstruction of a hair follicle 6cm above the anus, caused by an ingrown hair. Forms an abscess with foul discharge.
- Most common in obese males from Asia/ middle east
Describe symptoms for:
1) Ischiorectal abscess
2) Supralevator abscess
3) Intersphincteric abscess
1) Ischiorectal: systemic illness and extreme pain on DRE (in fossa full of fat with no barriers to prevent spread on infection)
2) Supralevator: inflammation of adjacent to bladder > systemic illness, primal discomfort and bladder irritation
3) Intersphincteric: chronic anal pain and tenderness on DRE
