GI + Colorectal 2 Flashcards

1
Q

What are diverticula

A

Diverticula are small, bulging pouches that can form in the lining of your digestive system

Occur due to hypertrophy of the muscle propria, with diverticula then occurring at sites of potential weakness in the bowel wall (entry points of blood vessels)

This creates a ‘true’ diverticulum of just mucosa, without the muscular covering (as opposed to Meckel’s)

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2
Q

What is diverticulosis?

A

The presence of diverticula

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3
Q

What is diverticulitis?

A

The inflammation of diverticula

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4
Q

What is diverticular disease?

A

Symptomatic diverticula

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5
Q

Where are diverticula commonly found?

A

In the sigmoid, with 95% of the complications arising at this site

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6
Q

What are the causes of diverticula?

A

Low fibre diet (hard stools and thus higher pressure needed to move them)

Rarer associations: Marfans, Ehler’s Danlos syndrome and PKD

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7
Q

What are the clinical features of diverticular disease?

A

Mimic carcinoma of the colon:
Left sided colic, relieved by defecation
Altered bowel habit - including blood and mucus passage
Nausea
Flatulence
Severe pain and constipation if severe (causing lumina narrowing)

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8
Q

What investigations should be done for diverticular disease?

A

PR - may reveal pelvic abscess or colorectal cancer - main ddx

Sigmoidoscopy / Colonoscopy
Barium enema
CT

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9
Q

what is the management of diverticular disease?

A

Mebeverine = 1st kline medical management

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10
Q

What are the clinical features of Diverticulitis (infection)

A

Infection due to stagnation of the contents of teh diverticula

Severe left sided colic
Constipation (or overflow diarrhoea)
Symptoms mimicking appendicitis but on the left

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11
Q

What are the signs of diverticulitis?

A

Fever + tachycardia
Tenderness, guarding and rigidity on the left hand side
Can be a palpable mass in the LIF
Raised WCC and inflammatory markers

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12
Q

What is the management of diverticulitis?

A

Mild Attacks - low grade fever:
Bowel rest (fluids only) at home
Oral co-amoxiclav +/- metronidazole

Severe attacks (complicated - high grade fever)
Admit if pain cannot be controlled, or oral fluids not tolerated
Give analgesia, IV fluids, IV cefuroxime and metronidazole and keep NBM
Order erect CXR, AXR and contrast CT to assess for complications
DO not scope in acute attack

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13
Q

What complications can arise from diverticulitis?

A
Perforation
Bleeding
Stricutre
Abscess 
Fistula
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14
Q

What does perforation lead to following diverticulitis?

A

Formation of paracolic or pelvic abscess, fistulae or generalised peritonitis

Presents with ileus +/- shock
Mortality = up to 40%
Management is with laparotomy +/- Hartman’s procedure

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15
Q

What is the presentation and management of abscess formation following diverticular disease?

A

Swinging fever, leucocytosis and localising signs (e.g. a boggy rectal mass)

Should be drained under CT guidance

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16
Q

How does bleeding following diverticular disease present?

A

Sudden, painless bleeding and also chronic occult loss, as a result of erosion of vessels at the fundus of the diverticulum

Large volumes can be lost, requiring transfusion
These often stop with bed rest
If they do not stop, locate the bleeding point via angiography (or colonoscopy) and then treat with embolisation (surgery rare)

Adrenaline injections and diathermy may negate the need for surgery

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17
Q

What kind of fistulas can form following diverticular disease?

A

Colovesical - leading to UTI and pneumaturia

Colovaginal - leading to foul discharge

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18
Q

Where does intestinal obstruction most commonly occur following diverticular disease?

A

Most commonly in the sigmoid after repeated episodes of diverticulitis
Chronic inflammation leads to scarring and the formation of a diverticular mass, which causes obstruction and may mimic colonic carcinoma

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19
Q

What is the management of asymptomatic diverticula of the colon?

A

Dietary advice is required for asymptomatic diverticulae

Increase unprocessed food intake and dietary fibre intake as part of a balanced diet (>20g/day of insoluble fibre)

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20
Q

What is the management in patients with uncomplicated by symptomatic diverticula disease?

A

Mebeverine first line
If there is very severe or recurrent diverticulitis, surgery may be considered
Rarely resorted to, complication rates are high

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21
Q

What are the indications for surgery in diverticular disease?

A

Small confined pericolonic abscess rarely require surgery
Any generalised peritonitis will require surgery
Emergency colonic resection required in massive haemorrhage / perforation

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22
Q

What are the risk factors of colorectal carcinoma?

A
Family history (+FAP/HNPCC)
Age
Western diet - low in fibre, high in fats - exercise, obesity 
UC (Chron's if it is in the colon) 
Smoking

POLYPS

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23
Q

What are the protective factors against colorectal carcinoma?

A

Fruit and vegetables / fibre consumption
Exercise
HRT
Aspirin / NSAIDs

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24
Q

Which gene is related to colorectal cancer?

A

Hereditary non-polyposis colorectal cancer (HNPCC) is responsible for <5% = arises from germline mutations in mismatch repair genes

Familial adenomatous polyposis (FAP) is responsible for <1% cancers, and occurs due to tumour suppressor gene APC mutations

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25
Describe the morphology of colorectal cancer
Mostly adenocarcinoma with characteristic 'signet ring' cells on histology
26
What % of colorectal cancers occur in which section?
``` Caecum and ascending colon: 15% Transverse colon: 10% Descending colon: 5% Sigmoid colon: 25% Rectum 45% ```
27
What is the initial appearance of colorectal cancer? How does it invade?
Usually appear as a polypod mass with ulceration, spreading initially by direct infiltration through the bowel wall Then involves the lymphatics and blood vessels, metastasising primarily to the liver Transcoelemic spread can also occur
28
How is cancer staged?
TNM Used to be dukes A - tumours invade submucosa +/- muscularis propria (confined to lining of bowel) B - tumours invade past the muscularis propria (into subserosa/directly into other organ, no nodal involvement) (through wall of bowel C - Regional lymph node involvement D - distant mets
29
Describe the stages of TNM staging
T = tumour (TX - cannot be evaluated) T1: the tumour is in the submucosa T2: tumour has grown into muscularis propria T3: Tumour in subserosa T4: The tumour has grown into the surface of the visceral peritoneum - all layers N = nodes N1a there are tumour cells in 1 regional node N1b (2-3) N2a: tumour cells in 4-6 LN 2b: 7+ regional LN M0 = no mets M1a: one other part of body 1b: more than 1 other part of the body 1c: cancer spread to peritoneal surface
30
Describe the grading of tumours in colorectal cancer
GX: cannot be identified G1: the cells are more like healthy cells (well differentiated) G2: the cells are somewhat like healthy cells - moderately differentiated G3: the cells look less like healthy cells (poorly differentiated) G4: The cells barely look like healthy cells (undifferentiated)
31
What kind of cancers are Anal cancers?
Mainly SCC
32
What are the risk factors for anal cancer?
Anoreceptive sex Syphilis infection Anal warts/cervical caner - HPV immunosuppression
33
What is the pectinate line?
An embryological division between the upper 2/3 and the lower 1/3 of the anal canal
34
Describe the epithelium above the pectinate line
Columnar epithelium, lymph drainage to internal iliac nodes and portal venous drainage, thus hepatic metastasis
35
Describe the epithelium below the pectinate line
Squamous epithelium, lymph drainage to the superficial inguinal nodes, and caval venous drainage, thus pulmonary metastases More common in men, better prognosis
36
What are the presentation of a colorectal tumour?
Abdominal mass, abdominal pain, haemorrhage, perforation or fistula
37
How do right sided tumours tend to present? (CAECUM)
Often asymptomatic and may present with IDA/weight loss ``` Anaemia Obstruction (ileocaecal: SBO - bilious/faeculant) Mass dyspepsia, pain - colicky Appendicitis ```
38
How do left sided tumours tend to present? (RECTAL)
``` PR blood/mucus, altered bowel habit tenesmus obstruction - large bowel Pain - lower bladder sx ? ``` mass on PR examination
39
What is the presentation of anal tumours?
bleeding, pain, changes in bowel habit, pruritus ani, masses or stricture
40
What are the indications for 2ww referral in patients >40
Rectal bleeding or change in bowel habit for >6w Persistent rectal bleeding, in those over 45, with no obvious evidence of benign anal disease IDA Hb <10g/dl without an obvious cause Palpable abdominal / PR mass
41
What Ix are done for patients with suspected colorectal carcinoma?
FBC (microcytic anaemia), LFTs (metastatic indicator) FIT Colonoscopy (gold standard, as allows biopsy (polypectomy) non-contrastCT chest, abdo, pelvis (staging) Carcino-embryonic antigen (CEA) can be used to monitor disease MRI (rectal cancer) ?Chest mets: CT CAP Double contrast: barium and air - cancer appears like an apple core
42
Describe the surgical procedures for colorectal cancer?
``` Wide resection of the growth and regional lymphatics Right hemicolectomy left hemicolectomy sigmoid colectomy anterior resection abdomino-perineal resection Hartmann's procedure - resection of rectosigmoid colon with closure of the anorectal stump and formation of an end colostomy Endoscopic stenting ```
43
What are the indications for a right hemicolectomy?
For caecal, ascending and proximal transverse colon tumours | may be temporary end ileostomy prior to ileo-colic anastomoses
44
What are the indications for a a left hemicolectomy?
For distal transverse or descending colon tumours | may be temporary end colostomy prior to coli-colic anastomoses
45
What are the indications for a sigmoid colectomy
high anterior resection | for sigmoid tumours
46
What are the indications for an anterior resection?
For low sigmoid/high rectal tumours | colorectal anstamosis achieved at first operation, although this may be covered by a temporary loop ileostomy
47
What are the indications for an andomino-perineal resection
for tumours low in the rectum permanent colostomy with removal of rectum and anus no anastomosis
48
What are the indications for a Hartmann's procedure?
For bowel obstruction or palliation | Resection of recto-sigmoid colon, with temporary end colostomy and closure of the rectal stump
49
What is the indication for endoscopic stenting?
Palliative
50
How is radiotherapy used to manage colorectal cancers?
Used pre-operatively in rectal cancer to reduce recurrence and increase survival Higher risks of post-operative complications (DVT, pathological fractures, fistula formation) Post-operative radiotherapy is only used if high risk of local recurrence
51
How is chemotherapy used to manage colorectal cancers?
Adjuvant 5-FU (and folic acid) can reduce mortality of higher stage tumours May be used in palliation of metastatic disease
52
What is the treatment of anal carcinoma?
Radiotherapy plus chemotherapy (5-FU and mitomycin/cisplatin) 75% retain normal anal function
53
What are the requirements for patients having surgery for CRC?
Colonoscopy before or soon after to look for additional lessons as 5% of tumours are metachronous
54
How should patients having surgery for CRC be followed up?
Stage II/III disease should have serum CEA every 3 months and colonoscopy every 3 years NHS bowel screening programme offers screening to all men/women aged 60-69 via Faecal immunochemical Test (FIT) sampling every 2 years Colonoscopy is used in those most at risk due to personal history, family history, adenoma or IBD
55
What is the manamgent of an obstructing colon cancer?
A-E: IV fluids to replace losses, catheter for fluid balance. Bloods for amylase, FBC and U+E Analgesia and NG tube decompression AXR and erect CXR - confirm diagnosis and check for perforation CT to determine level of obstruction Gastrograffin follow through studies can also show the level of obstruction, and also have some therapeutic effects on mild mechanical obstruction Definitive surgery is the management once the patient is adequately hydrated (or endoscopic stenting for palliation)
56
What are the symptoms of a patient with a small/large bowel obstruction?
``` Vomiting: Undigested food suggests gastric outlet obstruction Bilous vomiting suggests upper SBO faeculent vomiting (thicker/foul smelling) suggests more distal SBO ``` Pain: colicky abdominal pain in early obstruction, pain may be absent in long standing obstruction Constipation: may not be absolute in proximal obstruction
57
What are the signs of a patient with a small/large bowel obstruction?
Distention Tinkling bowel sounds dehydration central resonance to percussion, dull flanks Scars: previous surgery causing adhesions Palpable mass (causing the obstruction No abdominal tenderness (unless strangulation)
58
What are the common causes of small bowel obstruction?
Adhesions (80%) Hernias Chron's disease Intussusception
59
What are the common causes of large bowel obstruction?
Carcinoma of the colon Diverticular disease Sigmoid volvulus Constipation
60
What are the complications of bowel obstruction?
Bowel becomes oedematous and distends bacteria proliferate in the obstructed bowel As the bowel distends, vessels become stretched and the blood supply is compromised, leading to strangulation (ischaemia and necrosis) Eventually, bowel will perforate Symptoms develop more gradually in large bowel obstruction - due to the capacity
61
What investigations are appropriate in a patient with suspected obstruction?
FBC U+E amylase, LFTs ABG Urinalysis Supine AXR: distended proximal bowel, absent gas distally Erect CXR: fluid levels in SBO, air under diaphragm if perforation Contrast enema: Differentiates obstruction and pseudo-obstruction, can identify the level of obstruction and ileo-caecal competency Gastrogaffin CT can indicate level of obstruction but cannot always give the diagnosis
62
What is paralytic ileus?
Temporary disruption of normal peristaltic activity without mechanical blockage No bowel sounds
63
What are the causes of paralytic ileus?
Post surgery (normal up to 4 days) Due to anastomotic leak (intra-abdominal sepsis) Electrolyte disturbances Critically unwell patients on ITU with multiple injuries
64
How is paralytic ileus managed?
Still carries the same risk of third space losses: treated with NG and NBM. Must remain vigilant in monitoring as may silently develop into a mechanical ileus caused by adhesions and thus it is important to remain vigilant in monitoring
65
How do you differentiate SBO and paralytic ileus?
Bowel sounds: Present in SBO, absent in paralytic ileus AXR: air in the colon in paralytic ileus, none in SBO Diffuse air-fluid levels in paralytic ileus
66
What is pseudo-obstruction?
the name for large bowel obstruction when no identifiable cause can be found (form of paralytic ileus)
67
When does strangulation occur?
Most commonly occurs with volvulus or hernia | Can occur in any obstruction
68
What are the differentiating features of strangulation?
Increasing pain/tenderness with leucocytosis and systemic upset May progress to peritonism with absent bowel sounds
69
What is volvulus?
A twisting loop of bowel around its mesenteric axis, resulting in obstruction together with venous occlusion at the base of the mesentery
70
Who gets sigmoid volvulus?
Most common in elderly, constipated patients
71
What is the AXR appearance of sigmoid volvulus?
Coffee been appearance
72
What is the management of sigmoid volvulus?
Insertion of a long flatus tube advanced into the sigmoid, which often untwists the volvulus (releases large amounts of liquid faeces/gas) If this is unsuccessful, there will be an emergency laparotomy
73
What is a caecal volvulus?
Due to congenital malrotation, and gives the classic 'embryo' appearance of an ectopically placed caecum on an AXR Treatment is untwisting at laparotomy
74
SBO vs LBO vomiting
bilious in SBO | Absent/faeculant in LBP
75
SBO vs LBO constipation
May not be absolute in SBO | Absolute in LBO
76
SBO vs LBO Progression
More rapid in SBO than LBO
77
What is the management of a patient with SBO?
ABCDE resuscitation Drip and suck: NBM + NG decompression of the stomach (Ryle's tube) If no signs of strangulation, delay operative management by 48 hours (50% SBO due to adhesions will resolve with conservative management after 4 days) If signs of strangulation or severe obstruction then the patient will be taken to theatre, and the aetiology of the obstruction dealt with surgically Antibiotic therapy will also be commenced if there are signs of strangulation
78
What is the management of LBO?
Generally requires operative management (Hartmann's) | If due to faecal impaction, enemas or manual evacuation will be tried
79
What is intussusception?
Telescoping of the bowel
80
What is the presentation of intussusception?
Intermittent colic, red-currant jelly PR bleeding and a sausage shaped mass in the upper abdomen
81
What is the USS sign of intussusception?
Target sign
82
What is the treatment of intussusception?
Air insufflation
83
What are the causes of intestinal obstruction in children?
Intussusception Incarcerated hernia Malrotation of the bowel with midgut Volvulus - presents as obstruction with PR blood/mucous + abnormal bowel position on AXR Hirschprung's disease Meconium ileus
84
What are the factors causing constipation?
General: poor diet, dehydration, lack of exercise, IBS, old age, pain Anorectal disease: fissure, stricture, rectal prolapse Metabolic/endocrine: hypercalcaemia, hypothyroid, hypokalaemia Drugs: Opiates, anticholinergics, iron, aluminium based antacids, diuretics Neuromuscular: spinal/pelvic nerve injury, diabetic neuropathy, hirschprung's disease
85
What investigations are done in constipation?
Bloods: FBC, ESR, U+Es, Calcium, TFTs and endoscopy
86
Where does the anal canal run from and to?
Superior aspect of the pelvic diaphragm to the anus and is normally collapsed
87
What is the internal anal sphincter?
Involuntary sphincter surrounding the upper 2/3 of the anal canal
88
How does the anal sphincter maintain faecal continence
Tonic contraction is stimulated by sympathetic fibres from the superior rectal/hypogastric plexus Parasympathetic fibres inhibit this tonic contraction, thus requiring contraction of puborectalis / the external anal sphincter to maintain continence
89
What is the external anal sphincter?
Surrounds the Lower 2/3 of the anal canal and is under voluntary control, mediated by the inferior recall nerve
90
What are the anal cushions?
Highly vascular areas, formed of smooth muscle with sub epithelial anastomoses of the rectal arteries/veins The anal cushions contribute to the continence along with the anal sphincter, and are at 3, 7 and 11 o clock when viewed from the lithotomy position (legs up in surgery)
91
What are haemorrhoids?
Prolapses of these cushions, containing the normally dilated rectal venous plexus covered by rectal mucosa Arise due to a breakdown of the smooth muscle layer, the muscularis mucosae
92
What are the factors predisposing to haemorrhoids?
Mainly idiopathic Increased anal tone (chronic constipation) Factors that cause congestion of superior rectal veins (cardiac failure, pregnancy, rectal carcinoma, any raised IAP)
93
Where does the superior rectal vein drain into?
The inferior mesenteric vein (portal) whereas the middle/inferior rectal vein drain cavally Essentially, the anastomoses of the anal cushions are porto-canal anastomoses, so in portal hypertension, they may become varicose to give ano-rectal varices (can co-exist with haemorrhoids in patients with portal hypertension)
94
Describe the classification of haemorrhoids?
1st degree: confined to the anal canal: bleed but do not prolapse 2nd degree: prolapse on defecation, then reduce spontaneously 3rd degree: prolapse outside the anal margin on defecation, but may be manually reduced 4th degree: remain prolapsed outside the anal margin at all times
95
What are the symptoms of haemorrhoids?
``` Rectal bleeding: bright red blood on paper Prolapse Mucous discharge Pruritus ani Pain if the piles become thrombosed ```
96
What are the complications of haemorrhoids?
Anaemia - if severe/continued bleeding Thrombosis
97
How does thrombosis of piles occur?
If prolapsing piles are gripped by the anal sphincter (strangulated piles), then venous return is occluded, leading to thrombosis The haemorrhoids swell, become purple and tenderness, causing significant pain/distress The thrombosed piles often fibres within 2-3 weeks, giving spontaneous cure Management is conservative, with cold compress, opioids and rest
98
How should a patient with ?haemorrhoids be examined?
Abdo exam: palpable masses, enlarged liver Rectal exam: prolapsing piles are obvious Proctoscopy/rigid sigmoidoscopy: can visualise the piles, and assess for a lesion higher in the rectum Colonoscopy / Flexi-sigmoidoscopy: if symptoms suggest a more sinister pathology
99
What are the differential diagnoses of rectal bleeding?
Haemorrhoids Anal fissure: very tender, skin tag Diverticulitis: bloody 'splash' in pan, LIF symptoms Rectal cancer (tenesmus, PR bleeding with defecation) Colon cancer (red blood mixed with the stool, change in bowel habit) UC: abdominal pain, urgency) Chron's disease: weight loss, chronic diarrhoeah Massive upper GI bleed: melena, but frank blood if very large, usually haematemesis also Trauma Ischaemic / infective colitis Angiodysplasia
100
How are haemorrhoids managed?
Advice: plenty of fluid and not to strain Topical analgesia/astringents and bulk forming laxative: anusol Sclerotherapy Banding Surgery
101
What is sclerotherapy/how is it done?
5% phenol in almond oil injected above each pile as a sclerosing injection Suitable for first and second degree piles Painless as placed high in the canal, above the dentate line One or more repeat injections may be needed at monthly intervals
102
What is banding and how is it done?
Application of a small rubber band to the protruding mucosa This leads to strangulation Can be applied to first to third degree piles Care may be taken to position the band above the dentate line
103
What are the indications for surgery in piles?
Third and fourth degree piles stapled haemorrhoidectomy or haemorrrhoidal artery ligation are the main methods used (haemorrhoidectomy now less common)
104
What is a perianal haematoma?
Thrombosed external pile however, unlike internal haemorrhoids, it is covered by squamous epithelium supplied by somatic nerves and thus is painful
105
What is the presentation of a perianal haematoma?
acute, sudden pain and lump at the anal verge OE, lump is tense, smooth, dark blue and cherry sized Untreated, either subsides over a few days to leave a fibrous tag or rupture to discharge clotted blood
106
How is a perianal haematoma managed?
Incised and drained under local anaesthetic | If they are already discharging or being resorbed when seen, hot baths and reassurance is all that is necessary
107
What are the anal sinuses/crypts?
Small recesses that act to release mucous when compressed by faeces, to aid the evacuation of the anal canal these crypts are the most common sites of infection, but these can spread to various sites Perianal infections most commonly affect anon-receptive males, presenting with a visibly red, exquisitely tender swelling next to the anus
108
What are the different types of perianal infections?
Anorectal abscesses Pilonidal sinus Perianal warts
109
What Is the cause of an anorectal abscess?
Usually caused by gut organisms Associated with Chron's, DM and malignancy 45% are perianal with 30% ischiorectal, 20% intersphincteric and 5% supralevator
110
What is the treatment of an anorectal abscess?
Incision and drainage under GA, to prevent rupture / possible formation of fistula
111
What is the cause of a pilonidal sinus?
Obstruction of natal cleft hair follicles around 6cm above the anus, with ingrowing of hair leading to a foreign body reaction This can lead to abscess formation, or tracks to teh skin in a 'pilonidal sinus' with foul discharge Most common in obese males, particularly from Asia/Middle East
112
What is the treatment of a pilonidal sinus?
Excision of the sinus tract and primary closure, with pre-op antibiotics Hygiene and hair removal advice should be given
113
What are the treatments for perianal warts?
Podophyllin paint, cryotherapy or surgical excision | Those secondary to syphiis can be treated with penicillin
114
How are perianal infections examined?
Diagnosis = usually straightforward, however deep sepsis higher up the anal canal may require EAU or imagine Any discharging area near the anus should be assumed to communicate with the anorectic until proven otherwise Operative exploration is often the first diagnostic test, although MRI can be used
115
What is a 'fistula in ano'
A track that communicates between the skin and the anal canal / rectum c.f. a sinus which is a track, leading from source of the infection to the surface Usually the result of an abscess discharging to form a fistula. Symptoms are thus of an anorectal abscess, followed by recurrent episodes of infection
116
Describe the aetiology of a fistula in ano
``` TB Chron's Diverticular disease Rectal carcinoma Immunocompromised individuals e.g. HIV ```
117
What investigations can be done for a fistula in ano?
Examination of the tract is extremely painful and thus should only be done under anaesthetic MRI Endoanal USS
118
What is Goodsall's rule?
Relates the external opening of an anal fistula (compared to the transverse anal line) to its international opening Posterior fistulas will have a curved track with their opening in the posterior midline Anterior fistulas will have a direct opening into the anal cavity Exception: anterior fistulas that lie more than 3cm from the anus, which may drain like posterior fistulas with a. curved track to the posterior midline
119
What is the management of fistula in ano?
Superficial and Low level fistulae are laid open to heal by secondary intention (fistulotomy) High fistulae (involve the continence muscles of the anus) Amy be injected with fibrin glue or a fistula plug If these methods fail, a seton suture gradually tightened over time can be used to maintain continence (ensures the sphincter is fixed by scar tissue before the tract is divided by tightening the suture Recurrent fistulae associated with Chron's may respond to metronidazole
120
What is an anal fissure
Tear in the sensitive anal canal distal to the dentate line, producing pain on deecation
121
What are the symptoms of an anal fissure?
Pain, worse on defecation, lasting for hours afterwards Associated constipation Pruritus ani Bleeding on defecation
122
What will you see on examination of an anal fissure?
Midline longitudinal tear in the rectal mucosa (90% posterior, 10% anterior due to parturition 'Sentinel pile or mucosal tag at the external aspect PR may not be possible due to pain and sphincter spasm proctoscopy and sigmoidoscopy should be performed under anaesthesia to exclude other anorectal diseases. Enlarged nodes in the groin suggest a complicating factor
123
What is the cause of anal fissure?
Hard faeces, with 10% of anterior tears due to parturition Thought to occur at the midline more as the blood supply to this area is worse, and thus, healing is difficult Rarer causes: infections (syphilis/herpes), trauma, Chron's, anal cancer and psoriasis
124
What is the management of anal fissure?
May heal spontaneously, with local anaesthetic ointments and lubricant laxative High fibre diet, plenty of fluids and bulk forming laxative If chronic: GTN cream used to relax anal sphincter and allow torn epithelium to heal (can give headaches) Bo-TOx injection has the same effect and can last up to 8 weeks, but there is a small incidence of incontinence afterwards Intractable fissures or recurrent cases may require a sphincterotomy (submucosal division of the external sphincter under GA)