Anal disorders Flashcards
Define haemorrhoids
Abnormal vascular dilatation of anal mucosal cushions
How are haemorrhoids classified?
External or internal depending on origin in relation to the dentate line (transition between upper and lower anal canal).
Define external haemorrhoids (3)
Originate below dentate line
Covered by modified squamous epithelium (anoderm)
Richly innervated with pain fibres ➔ itchy and painful
Define internal haemorrhoids
Originate above dentate line
Covered by columnar epithelium
No pain fibres ➔ not sensitive to touch, temperature, or pain (unless strangulated)
What and where is the dentate line?
The transition between the upper and lower anal canal. Located 2cm from the anal verge.
Outline grading of internal haemorrhoids
I. project into lumen of anal canal but does not prolapse
II. prolapse on straining but reduce spontaneously when straining stops
III. prolapse on straining and requires manual reduction
IV. prolapsed and incarcerated and cannot be reduced
List 3 risk factors for haemorrhoids
Constipation Straining while trying to pass stools Increasing age Heavy lifting Chronic cough Pregnancy, childbirth Obesity
Name 3 complications of haemorrhoids
Ulceration Skin tags Maceration of perianal skin (softening and breakdown of skin) Ischaemia Thrombosis Gangrene
Rare: perianal sepsis, anaemia
Describe the presentation of haemorrhoids
Bright red, painless rectal bleeding (not mixed with faeces)
Discomfort
Pruritus ani
Tenesmus
Pain if Grade IV internal haemorrhoid or thromboses external haemorrhoid
How are haemorrhoids investigated?
Proctoscopy
Sigmoidoscopy: used if sinister symptoms are present or elderly
Outline the non-pharmacological management of haemorrhoids
Healthy, high fibre diet
Increased fluid intake
Minimising straining
Good anal hygiene: aids healing, reduces irritation
Outline the pharmacological management of haemorrhoids
Simple analgesia e.g. paracetamol
Consider topical analgesia
-avoid NSAIDs if rectal bleeding present
Faecal softeners (decusate sodium and glycerol suppositories)
Laxative: osmotic movicol, or bulk fibrogel
Outline the secondary care management of haemorrhoids
Band ligation
Injection sclerotherapy
Haemorrhoidectomy
Haemorrhoidal artery ligation (HALO)
Define anal fissure
A tear or ulcer in the lining of the anal cannel, immediately within the anal margin
What is the commonest age group affected by anal fissures?
15-40yrs
Describe the presentation of anal fissure
Anal pain with defecation +/- bright red rectal bleeding
Anal spasm
Differentiate between acute and chronic anal fissures
Acute (<6wk) are superficial with well-demarcated edges
Chronic (6+wk) are wider and deeper with muscle fibres visible in the base. Edges often swollen, and skin tag may be visible.
Outline the non-pharmacological management of anal fissures
High fibre diet
Increased fluid intake
Avoid straining
Good anal hygiene
Outline the pharmacological management of chronic anal fissures
Analgesia
GTN 0.4% cream - if unhealed after 6-8wk with notable symptomatic improvement
Topical diltiazem 2% cream - if unhealed after 6-8wk, but no notable symptomatic improvement
Botox injection into internal sphincter
Outline the surgical intervention for anal fissures
Lateral sphincterotomy - reduces internal sphincter spasms that impaired anal blood supply and reduced fissure healing
Avoid in females due to complications with childbirth and UTIs
Describe the presentation of perianal abscess
Gradual onset, constant localised perianal pain
Associated swelling with tenderness +/- discharge
May have associated systemic features: fever, malaise, anorexia
Name 2 organisms commonly implicated in perianal abscess
E. coli
Enterococcus spp.
Bacteroides spp.
Name 3 risk factors of perianal abscess
Crohn's disease Diabetes mellitus Anal fistula Steroid use Immunodeficiency
Outline the management of perianal abscess
Surgical emergency
Incision and drainage
Describe the pathophysiology of perianal abscess and subsequent fistula
Crypts of Morgagni that penetrate the internal sphincter become infected. This allows pus to tract to the anal margin and form an abscess.
If the abscess resolves, there is a fistula in this location connecting the anal cavity to the perianal skin.
Outline the management of anal fistula
Seton stitch: A thread inserted through the fistula tract and tied outside in a loop. This allows the infection to drain and heal, without damaging the sphincter muscles.
Fistulotomy: Laying open of the fistula to allow healing by secondary intention.
Define pilonidal sinus disease
Skin disorder featuring openings in the midline of the natal cleft, that allow loose hair and debris to enter creating an epithelial track (sinus)
Name 3 risk factors for pilonidal sinus disease
Male 15-40yr Caucasian Hirsutism Obesity
Describe the presentation of pilonidal sinus disease
Asymptomatic, or
Acute: pilonidal abscess
Chronically discharging sinus
Name 2 complications of pilonidal sinus disease
Cellulitis
Sepsis
Chronic pain
Altered body image
Outline the management of acute pilonidal abscess
Urgent incision and drainage
Analgesia
Advice to reduce recurrence: perianal hygiene, buttock hair removal techniques
Outline the primary care management of discharging pilonidal sinus disease
Refer to colorectal or general surgical unit
Analgesia
Antibiotics if cellulitis suspected
Outline the surgical management of discharging pilonidal sinus disease
For recurrent abscess or a small sinus ➔ pit picking method (removal of midline pit), excision of superficial abscess scars, drainage of track.
For chronic discharging sinuses ➔ wide excision of sinus tracks + primary closure or leaving wound open to heal by secondary intention. Cover with tissue flap if possible to minimise infection risk.
What is the commonest type of anal cancer?
Squamous cell carcinoma (80%)
Name 3 types of anal cancer
Squamous cell carcinoma (80%)
Melanoma
Lymphoma
Adenocarcinoma
Outline the epidemiology of anal cancer
Uncommon (only 4% of lower GI cancers)
Incidence 1 in 10,000
F>M
Which anal cancers are commoner in men?
Anal margin tumours: well differentiates, good prognosis
Which anal cancers are commoner in women?
Anal canal tumours: poorly differentiated, worse prognosis
Where do anal cancers most commonly metastasise?
Liver
Lungs
Name 3 risk factors for anal cancer
Human papilloma virus (HPV): HPV risk increased by anal intercourse and high number of sexual partners
Men who have sex with men
HIV-positive
Immunosuppression in transplant recipients
Cigarette smoking
Previous malignancy
Describe the presentation of anal cancer
Rectal bleeding (50%) Perianal pain Palpable lesion Faecal incontinence +/- mucus discharge Perianal pruritus
20% asymptomatic
How should anal cancer be investigated?
Rectal examination and biopsy
Staging: CT, MRI, endo-anal USS, PET
HIV serology
Metastases screening
What system is used to stage anal cancer?
TNM staging
Outline management of small well-differentiated carcinomas of the anal margin
Local excision
Outline management of anal cancers that are larger, poorly-differentiated, or outside of the anal margin
Combined modality chemotherapy (5-fluorouracil + mitomycin C) and radiotherapy
Salvage surgery
What are the surgical indications for anal cancer?
Tumours that fail to respond to radiotherapy
Large tumours causing GI obstruction
Small anal margin tumours without sphincter involvement
Outline the pharmacological management of acute anal fissures
Bulk forming laxatives
Non-opioid analgesia
Topical anaesthetic
