7 - Anorectal Flashcards
What are haemorrhoids and how are they classified?
Abnormal swelling or enlargement of the anal vascular cushions at 3, 7, 11 o clock in lithotomy position
1-4th degree based on size

What are some risk factors for haemorrhoids?
- Excessive straining from constipation
- Increasing age
- Raised intrabdominal pressure (pregnancy, chronic cough, ascites)
- Pelvic or abdominal masses
- Family history
- Cardiac failure
- Portal hypertension

What are the clinical features of haemorrhoids?
- Painless bright red rectal bleeding after defecation on paper or on surface of stool (NOT mixed in)
- Pruitis
- Rectal fullness or anal lump
- Soiling
- If thrombosed can be painful, blue, oedamtous and tender

What are some differentials for haemorrhoids??
Need to exclude other causes of rectal bleeding
- Malignancy
- IBD
- Diverticular disease
- Sentinel piles from fissure-in ano

How are haemorrhoids investigated?
- Do a PR exam if possible and look at perianal skin
- Proctoscopy to confirm
- FBC to checl for anaemia
May need to do flexi sig or colonoscopy to rule out malignancies

How are haemorrhoids managed?
Conservatively (more common)

- Lifestyle advice (increase fibre and fluid intake)
- Laxatives
- Topical lignocaine
- Avoid opioids
- Reassurance bleeding not sinister
Non Surgical (symptomatic 1st and 2nd degree)
- Rubber band ligation
Surgical (2nd-4th degree)
- Haemorrhoidal artery ligation for 2nd+3rd degree
- Haemorrhoidetomy for 3rd or 4th not suitable for banding (Milligan Morgan or Stapled)
What are the complications of RBL and haemorrhoidectomy used in the treatment of haemorrhoids?
RBL: recurrence, pain, bleeding
Haemorrhoidectomy: bleeding, infection, constipation, stricture, anal fissure, fecal incontinence

What are the complications of haemorrhoids themselves?
- Thrombosis
- Ulceration
- Gangrene (secondary to thrombosis)
- Skin tags
- Perianal sepsis
What is the pathophysiology of a pilonidal sinus?
Formation of a sinus in the cleft of the buttocks, usually affect males 16-30 years
Hair follicle in the intergluteal cleft becomes infected or inflammed. The inflammation obstructs the opening of the follicle which extends inwards forming a pit
Foreign body type reaction then leads to formation of a cavity connected to the surface of the skin via sinus tract

What are some risk factors for developing a pilonidal sinus?
- Caucasian with coarse dark body hair
- Those who sit for prolonged periods of time
- Increased sweating
- Obesity
- Poor hygeine
- Local trauma

What are the clinical features of a pilonidal sinus?
- Discharging and intermittently painful sinus in sacrococcygeal region
- Abscess can arise when sinus infected and this is swollen, erythematous region with fluctuant tender mass
Distinguish from perianal fistula as does not communicate with anal canal. If not sure do rigid sigmoidoscopy or MRI to see internal opening of tract

How are pilonidal sinuses managed?
Conservative

- Shave affected region and pluck sinus free of any hair
- Wash sinus out with water to prevent infection
- Give antibiotics and surgical drainage if abscess
Surgical
- For abscess I+D with wash out and further later surgery to remove sinus tract
- For chronic disease two methods of removing tract (see image)
What is the aetiology of a fistula-in-ano?
Abnormal connection between anal canal and perianal skin, often as a consequence of an anorectal abscess
Other risk factors: (see image)

What are the clinical features of a fistula?
Present with either recurrent perianal abscesses OR intermittent/continuous discharge onto the perineum (faeces, blood, pus, mucus)
External opening on the perinueum may be seen or covered in granulation tissue
May feel fibrous tract under skin on DRE

What is the Goodsall rule?
Predicts trajectory of fistula tract based on external opening

How do you investigate an anal fistula and how are they classified on diagnosis?
Proctoscopy to visualise the opening of the tract or MRI imaging if complex
Intersphincteric are most common, suprasphinteric least common

Patients are treated conservatily for fistulas if they are asymptomatic. If patients are symptomatic, what is the course of treatment?
No difference in recurrence rates between different methods. High tract course fistula has a higher change of incontinence impairment from treatment
- Fistulotomy: lay tract open by cutting through skin and subcut tissue and leave to heal by secondary intention
- Placement of Seton: more for high tract disease, placed through the fistula to try and bring it together and close the skin

If a patient has an anal fistula or recurrent peri-anal abscesses, what should you investigate the patient for?
Crohn’s
What is the pathophysiology of an anorectal abscess and how are they categorised?
Collection of pus in anal or rectal region, more common in men
Caused by plugging of the anal ducts that drain the anal glands that normally produce mucus to help the passage of faecal matter
Blockage of duct leads to fluid stasis and infection due to flora overgrowth by E Coli, Bacteriodes spp or Enterococcus spp
Anal glands in intersphincteric space so infection can spread to other areas and form abscesses in different areas

What is the most common location of an anorectal abscess?
Perianal

What are the clinical features of an anorectal abscess?
- Pain in the perianal region exacerbated when sat down
- Localised swelling, itching or discharge
- Will be erythematous, fluctuant, tender perianal mass that could be discharging puss or have cellulitis
(if deeper abscess may not see anything perianally but may have severe tenderness on DRE so need anesthesia for full assessment or CT/MRI)

How are anorectal abscesses managed?
- Abx (ciprofloxacin/metronidazole for 7/7)
- Analgesia
- I+D under GA left to heal by secondary intention
- Once drained do proctoscopy to check for any fistula-in-ano and if so use seton
- Post ob abx to lower risk of fistula formation

What is an anal fissure and how are they classified?
Tear in the mucosal lining of the canal often due to trauma from defecation of hard stool
- Acute <6 weeks
- Chronic >6 weeks
Can also be primary or secondary (IBD)

What are the risk factors for developing an anal fissure?
- Constipation
- Dehydration
- IBD
- Chronic diarrhoea













