Anorectal disease Flashcards
Causes of perianal pain
- Anal fissure
- Hemorrhoids
- Colitis
- Perineal abscess
- Anorectal carcinoma
Classification of hemorrhoids
Class 1: Seen on examination
Class 2: Prolapse but reduce spontaneously
Class 3: Manual reduction required
Class 4: Not reducible
Conservative Management anal fissure
- High-fibre diet
- Adequate fluid intake
- Sitz baths
- Topical analgesia
- Glycerin trinitrate intra-anal
- Stool softeners/osmotic/stimulant: docusate sodium, polyethylene glycol, bisacodyl
Management of hemorrhoids
High fibre diet, stool softeners Fluids Sitz bath Avoidance of straining Band ligation, infrared coagulation Hemorrhoidectomy
Important differential with non-healing anal fissue or fissure located other than posterior area of anus
Crohn Malignancy
Etiology and definition of anal fissure
- Longitudinal ulcer in skin lined anal canal
- Etiology- most commonly associated with passage/trauma when passing hard stool
Symptoms of anal fissure
- pain during and after defecation Internal spincter spasm= ++pain
- PR bleeding
- Pruritis
- Constipation
- Discharge
Diagnosis of anal fissure
History
Clinical examination
–>most common posteriorly, if anterior consider underlying condition
Tear
Sentinel skin tag
Surgical management of anal fissure
- Internal lateral sphincterotomy->incision of internal sphincter, not past dendate line
- Fluids, fibre, bulking agents
- After procedure may have key hole defect->incision may not heal properly leading to passive soiling
Mechanism of chronic anal fissure
Fissure->pain->+sphincter tone->ischemia->fissure
Will see anal papilla, exposed fibres of sphincter and anal skin tag
Classification of anorectal abscess
Perianal most common, fistula in ano posterior
Ischiorectal, transphincteric
Intersphincteric
Supralevator, suprasphicteric
Extrasphincteric
Etiology of abscess
Blocked anal gland->infected
Risks for perianal abscess
DM Immunocompromised Chrohs
Clinical features of perianal abscess
Throbbing, swollen, erythematous, discharge, fever
Management of perianal abscess
- Analgesia
- Start fluids->keep NBM, surgical consult
- Surgical drain
- Have warm baths/clean 2-3 day
- Consider antibiotics if polymicrobial, immunocompromised, DM, elderly ->Gentamicin, ampicillin + metronidazole
- Fluids, fibre, avoid hard stools
Risk factors for anorectal abscess and differential
- Fistula
- Chron’s
- Male
Differential
- Chrohns
- Infected sebaceous gland
- Hydradenitis suppurativa
Etiology of fistula in ano
Idiopathic Infection Crohns TB Cancer Iatrogenic Trauma Foreign body Radiation
Symptoms in fistula
Recurrent abscess Discharge Pain/discomfort
Diagnosis and investigations in fistula
- Examination->may find end tract on PR.
- Should determine level of internal opening in relation to levator mechanism
–>Anterior ex open- drain into anus at dendate line
–>Posterior take curved to enter anal canal in midline
- Investigations:
Sigmoidoscopy to rule out inflammatory bowel examine under anaesthesia
Fistulogram
Endoluminal US
MRI useful in complex
Management of high and low fistula
- Low(does not cross many spinchter muscles)->lay tract open with fistulotomy: can heal via secondary intention
- High (does cross sphincter muscles)->requires
a. seton procedure, or else with have flow incontinence, allows drainage of fistula + healing
b. Advancement flap->repair of internal gland with suture, then advancing skin to cover fistula
Clinical features in anal cancer
Pain
Pruritis
Bleeding
Moisture
Most commonly epidermoid type (SCC and variants)
Risk factors for anal cancer
Homosexual males
HPV
Anal sex
Syphillis/LGV HIV
Tobacco
Spread and detection of anal cancer
Spreads via lymphatics, usually detected late
Staging in anal cancer
Stage I T1 N0 M0
Stage II T2 N0 M0; T3 N0 M0
Stage III Tany N1 M0
Stage IV Tany Nany M1
T1 Tumour ≤ 2 cm in greatest dimension
T2 Tumour > 2–5 cm
T3 Tumour > 5 cm
T4 Tumour invades adjacent organ (vagina, urethra, bladder)
N0 No regional lymph node metastases
N1 Perirectal lymph node metastases
N2 Unilateral internal iliac/inguinal
N3 Perirectal and inguinal/bilateral internal/inguinal
M0 No distant metastases
M1 Distant metastases
Etiology of pruritis ani
Idiopathic Poor hygiene Haemorrhoids Fissure-in-ano Drug hypersensitivity and allergies Anal warts Fungal infection Parasites Faecal incontinence Anal cancer Premalignant conditions (e.g. Bowen’s disease) Systemic disease (e.g. renal failure, diabetes mellitus)
Management of pruritus ani
Management: Consider any underlying cause Wash with soft pad after defecation Avoid humid, perfumed Cotton underwear Avoid medicated soaps
Define internal and external hemorrhoids
Internal when from above dendate line External when below dendate line
Anatomy of anal canal
Includes
Define a pilonidal sinus
- Caused by a forceful insertion of a hair in the natal cleft->intense inflammatory response and epithelialisation.
- May be multiple and communicate via a deep cavity
- Chronic discharge is common
- Infection can occur->abscess
What is this
Pilonidal sinus
Epidemiology of pilonidal sinus
- Male
- 20 yo
- Hirsute
Pathophysiology of pilonidal sinus
- broken hair is driven into the skin of the natal cleft by a rolling action of the buttocks. This provokes a foreign body-type reaction, and chronic inflammation results in a mature sinus.
Clinical features of pilonidal sinus, diagnosis
- Sacrococcygeal discharge
- Sacrococcygeal pain and swelling
- Sinus tracts
- History of priior rupture of fluid in natal cleft
- Skin maceration
May become infected->fever and toxic, uncommon
Clinical diagnosis
Management: aymptomatic, w/o, w/ abscess and recurrent
- Hair removal + local hygeine
Symptomatic->
- Surgical (recurrent, failure of incision and drain, complex)
Excision and drainage under local/general
Karydakis->asymmetric flap
Unroofing w/ marsupialisation
Primary or secondary
- Antibiotics->amoxycillin/clavulanate
- Laser depilation hair removal
Arterial supply of the rectum and anus
- Superior rectal artery upper rectum from inferior mesenteric
- Middle rectal artery from internal iliac
- Inferior rectal from pudendal (branch of iliac)->supplies lower rectum and anus
Lymphatic drainage of rectum and anus
- Superior rectum-> inferior mesenteric
- Inferior rectum->pararectal nodes
- Anus->inguinal nodes
Label
- Rectal area->columnar, insensitive to pain
- Transitional area->flattened cuboidal columnar
- Anal area->stratified squamous, no hair or sweat, sensitive to pain
- Normal skin
What is the difference between hydradenitis suppuritiva and anal cryptic gland disease in relation to region they occur
- Hydradenitis suppurative is disease of the skin glands->occurs in region 4
- Anal cryptic gland disease-> occurs in region 2
Label
- Anal crypt->giving rise to glands, location of anal fissure
- Anal glands
- Dendate line
- Anal cushion-> hemorrhoids
Coronal section MRI anus and rectum identify structures
Identify
Label pelvic floor muscles
- Levator plate including levator ani
- Puborectalis (part of levator ani + PC, IC)
- External sphincter
Label
- Internal anal sphincter
- Rectal wall
Key tissue spaces label
- Intersphincteric->infection of anal crypt gland can cause infection here
- Supralevator->abscess can occur here
- Ischiorectal->less pain because tissue is fat and can expand. Fistula here ++incntinence ->repair involves cutting muscle, not function properly as sphincter
Differential for anal fissure
- Ulcer
Crohns
Syphillis
TB
- Pain
Thrombosed external pile
Intersphincteric abscess
Herpes
Cancer
Pathogenesis of hemorrhoids
- AV channels in the anal cushions
- Channels increase and decrease in size
- EAS important in continence
- IAS prevents liquid leakage. It is a fatigue resistant muscle
- Anal cushions prevent leakage of small amounts of liquid and gas
- Straining= engorgement of anal cushions= fragmentation of muscular mucosa= bleeding and prolapse
- Lack of fibre= engorgement of anal cushions
Function of anal cushions
Management of hemorrhoids: Non prolapsing / reducible
- Reduce, topical corticosteroids for grade 1
- Fibre, hydration, manage constipation
- Rubber band ligation (can do three at once w/o risk of stricture)
- Photocoagulation, arterial ligation sclerothermy
Management of hemorrhoids: Irreducible
- Diet, lifestyle…
- Band ligation (Grade 3)
- Hemorrhoidectomy (Grade 4 internal or external)
Details of hemorrhoidectomy and complications
- Procedure
- Type 1
- details
- Use diathermy – cut below the anal cushion but above internal sphincter (must find correct plane!!!)
- Dissect to the rectum
- No ligatures – heal by secondary intention
- Complications
- Anal stricture, bleeding, incontinence
- Post op
- Keep clean
- details
- Type 2
- Stapling – has better results, +recurrence
- Following
Recovery 2 weeks
High fiber, fluids, stool softners, sitz bath, analgesia
R/V with GP if ++pain, bleeding, fever
What is a perianal hematoma and management
- Thrombosis of SC perianal plexus
- Three day rule
If w/i 3 days of pain onset, incise to relieve pressure
Following 3 days, pain will resolve, leave alone
Fibrous anal polyp important points
- Not a rectal polyp
- Colour of skin, not pink like mucosa or purple like transitional zone
- Pain sensitive, not for rubber band ligation
Features of anal crohns
- Multiple anal lesions
- Edematous skin tags
- Blue crimson coloration of skin
- Involvement of labia or groin
- Indolent (non painful) ulceration
- Extensive anorectal sepsis
- High fistula->including rectovaginal fistula
Management of anal crohns
What is hydradenitis suppurativa- presentation, treatment
- Infection of apocrine skin glands, due to increased viscosity
- Young post puberty, associated with acne
- Tender discharging
- Induration->fibrosis
- Associated with fistula in ano and SCC
- Laying open or local excision, prophylactic antibiotics considered
Perianal STD: infection, clinical, rectum, special
Perianal melanoma and SCC, Pagets of anus
- Melanoma
Rare, blue anal nodule. May confuse with thrombosed hemorrhoid.
Biopsy
12-18 mo mean survival, rapid mets
Palliate excision
- Anal SCC
Behaves like skin cancer
Can co-exist with hemorrhoids + CRC
- Pagets
Treatment resistant eczema-> due to underlying adenoCa. Needs biopsy
Exclude rectal Ca
Manage with WLE
