Anorectal Disease Flashcards
An older pregnant lady with cardiac failure presents with painless bright red Pr bleeding after defecation, she also notes pruritis, rectal fullness and soiling. Define what she has and how could you classify it?
What are some differentials?
What would you do to confirm the diagnosis?
Haemorrhoids - abnormal swellings or enlargements of anal vascular cushion (3 at 3, 7 & 11 o clock), 4% population, peak 45-65yrs
Classified according to size:
1st degree - remain in rectum
2nd - prolapse through anus defecation spontaneously reduce
3rd - prolapse then require digital reduction
4th - remain prolapsed
DD rectal bleeding:
Malignancy, IBD, diverticula disease
Investigations:
Proctoscopy confirms
Prolonged/ severe bleeding - FBC + coagulation
Unsure - flexible sigmoidoscopy/ colonoscopy
How could haemorrhoids become an emergency? What are some other complications?
Large prolapsed can thrombosis -> v painful, purple/ blue, oedematous, tense & tender perianal mass
Complications: ulceration/ gangrene after thrombosis, skin tags, perianal sepsis
How do you manage haemorrhoids?
Most conservative:
⬆️fibre/ fluid, laxatives, topical analgesia (lignocaine gel), avoid opioids
Non-surgical:
1st/ 2nd degree - rubber band ligation (recurrence pain is band placed below dentate line/ bleeding), I fared coagulation, photocoagulation, bipolar diathermy, direct current electrotherapy, haemorrhoids artery ligation
Surgical:
5% eventually have haemorrhoidectomy - 3rd/ 4th degree - stapled or Milligan Morgan (bleeding, infection, constipation, stricture, fissures, faecal incontinence)
What is pilonidal sinus disease and who does it normally affect?
Inter-gluteal cleft hair follicle becomes infected/ inflamed -> obstructs the opening which extends inwards -> pit -> foreign body reaction -> cavity connected to surface by epitheliased sinus tract
Risk factors: Caucasian makes with coarse dark body hair who sit for prolonged periods, Xs sweating, buttock friction, obesity, poor hygiene, local trauma, 16-30yrs
A gentlemen presents with an intermittent red, painful and swollen mass in the sacrococcygeal region which sometimes discharges. What are your differentials and how will you distinguish between them?
Pilonidal sinus disease - opens up to the skin and doesn’t communicate with anal canal
Perianal fistula - connects to anal canal
If unsure: rigid sigmoidoscopy/ MRI
What treatment options are there for pilonidal sinus disease?
Non-surgical:
Shaving affected area, plucking any hair in sinus, washed out with water, antibiotics in specific episodes
Pilonidal Abscess:
surgical drainage with washout + antibiotics
Surgical:
Chronic disease - remove tract
• excision then lay open wound secondary intention (time, infection)
• excision then primary closure (recurrence, reconstructive surgery)
A patient presents with an anorectal abscess what are they likely to have associated with this? What history makes this problem seem more likely? What else increases the risk of this associated problem?
1/3 have an associated perianal fistula (abnormal connection between anal canal & perianal skin)
Features of perianal fistula: Recurrent PA abscesses Intermittent/ continuous discharge peritoneum (mucus, blood, pus, faeces) External opening perineum Fibrous tract under skin
Risk factors perianal fistulas: Perianal abscess IBD Systemic diseases e.g. TB, HIV, diabetes History anal trauma Anal Radiation therapy
Explain the Goodsall rule
Used clinically to predict the trajectory of a fistula tract
- external opening posterior to transverse anal line - curved course to posterior midline
- opening anterior to transverse anal line - fistula tract straight racial course to dentate line
Explain the park’s classification system
Divides anal fistulaes into 4 distinct types:
- inter-sphincteric (most common)
- trans- sphincteric
- extra- sphincteric
- supra- sphincteric (least)
How would you manage a perianal fistula?
- protocsopy & MRI complex fistula
- asymptomatic conservative
Surgical:
No difference recurrence different options
• fistulotomy (superficial/ submucosal) - laying tract open using probe-> secondary intention healing
• seton (rubber sling) brings together and closes fistula + prevents abscess forming
Any patient with anal fistula or recurrent perianal abscess should investigated Crohn’s
How are anorectal abscesses thought to be caused? How can they be classified?
Plugging of anal ducts (mucus secretion, between internal & external sphincters) -> fluid stasis -> infection (E.coli, bactericides spp, enterococcus spp)
~ collection of pus
Classified:
Perianal (mostly), ischiorectal, intersphincteric, supralevator
How would an anorectal abscess present?
Pain perianal region worse seated, swelling, itching, discharge, systemic features infection, erythematous, fluctuant, tender mass, surrounding cellulitis
M>WM
Deeper: not obvious externally but severe tenderness DRE -> EUA
Managing anorectal abscesses
Unclear/ complicated: CT/ MRI
Antibiotics
Analgesia
Incision & drainage -> secondary intention
Proctoscopy after to check for fistula
A patient presents with a 7 week history of intense pain and itching post-defecation lasting several hours. They sometimes get bright red blood when they wipe. They refuse DRE due to pain. What are you considering? How would you confirm the diagnosis?
Anal fissure - tear in mucosal lining of anal canal due trauma from defecation hard stool
Acute <6 weeks
Chronic > 6 weeks
Primary - no underlying disease
Secondary - e.g. IBD
90% posterior midline
Investigations: EUA if DRE not possible, within anal canal - proctoscopy, investigate cause if recurring/ anterior
Differentials: haemorrhoids, crohn’s, UC, anal cancer
How would you manage an anal fissure?
Medical (majority):
Reducing risk factors (high fibre/ fluid, SS laxatives e.g. movicol/ lactulose), topical anaesthetic (lidocaine/ hot baths - relax anal sphincter, GTN/ diltiazem cream - increases blood supply promote healing)
Surgical (chronic):
2. Botox injections internal sphincter
1. Lateral sphincterectomy (division internal sphincter)
Recurrence 1-5%, faecal incontinence
Explain the difference between the following: partial thickness rectal prolapse, full thickness RP & internal intussusception
PT - rectal mucosa protrudes out of anus, loosening/ stretching connective tissue often associated chronic haemorrhoids
FT - rectal wall protrudes out of anus, form of sliding hernia through defect in fascia e.g. from chronic straining/ cough/ vaginal deliveries
II - prolapse of rectum into distal rectum or anal canal without protrusion outside anus
An older lady with previous traumatic vaginal delivery and current anorexia and COPD presents with rectal mucus discharge, faecal incontinence, PR bleeding and ulcers what are you thinking and how would you investigate?
If she also had rectal fullness, tenesmus & repeated defecation what would be more likely?
A rectal prolapse
Investigate: examination, ask to strain if not visible, DRE (often weakened anal sphincter)
Suspected internal prolapse: defecating proctography, EUA
More likely an acute full thickness prolapse initially internal
How would you manage a rectal prolapse?
Conservative (unfit/ minimal symptoms/ children as most resolve):
Increase fibre/ fluids, minor mucosal may banded
Surgical:
Perineal approach (safer) - delformes Op (prolapsed lining rectal mucosa & underlying muscle reinforced plicated sutures Altemerer’s Op (resection redundant prolapsed bowel)
Abdo approach -
Laparoscopically, robotically or open. Rectopexy (rectum mobilised & fixed onto sacral prominence via sutures or mesh)
What is AIN (anal intraepithelial neoplasia)?
Precancerous condition affecting perianal skin or anal canal linked to squamous cell carcinoma & strongly linked to HPV 16/18 (80-90%)
High grade (2-3) is premalignant
What types of anal cancer can you get? What are the risk factors?
Rare, 4% colorectal cancers, 1 in 100000
Majority squamous cell carcinomas arising below dentate line
Remainder adenocarcinomas arising upper anal canal epithelium & crypt glans
Rarer: melanomas, Anal skin cancers
RFS: HPV HIV Older Smoking Immunosuppression Crohn’s
How would anal cancer present?
Rectal pain OR Rectal bleeding ~ 50%
Anal discharge
Pruritus
Palpable mass
Locally invasive: infection, perianal fistula
If sphincter involved: tenesmus, incontinence
Examination: ulceration, wart like lesions, masses (location from anal verge & circumference), lymphadenopathy inguinal (above dentate line mesorectal/ para-aortic/ paravertebral)
What investigations are required for suspected anal cancer?
- proctoscopy
- EAU + biopsy
- women smear test exclude CIN + further biopsies signs of VIN
- consider HIV test if risk factors
Imaging after biopsy confirms:
- USS- guided fine needle aspiration palpable inguinal LNs
- CT thorax- abdo-pelvis distant metastases
- MRI pelvis extending local invasion (T stage)
A patient has been recently diagnosed with anal cancer and wants to know if she requires surgery & if so what kind, what will you tell her?
Surgical excision usually reserved for advanced disease after failed chemoradiotherapy OR early T1N0 carcinomas:
- majority abdominoperineal resection (some posterior or total pelvic exenteration)
Reviewed every 3-6months for 2yrs (then spread out), most recurrences occur first 3yrs following surgery
She will be discussed MDT (oncologist, general surgeon, radiologist, specialist nurse)
Chemo-radiotherapy often first choice (bar T1N0)
Usually external beam radiotherapy anal canal + inguinal LNs + dual chemotherapy agents e.g. mitomycin C & 5-flurouracil
What are some complications from anal cancer and it’s treatment? How likely is a patient to survive?
Chemoradiation related pelvic toxicity (dermatitis, diarrhoea, proctitis, cystitis)
Longer term: fertility issues, faecal incontinence, vaginal dryness, erectile dysfunction, rectovaginal fistula
5 year survival rate: Tumour stage 1 - 69.5% 2 - 61.8% 3a - 45.6% 3b - 39.6% 4 - 15.3%
