Colorectal Flashcards
Haemorrhoids
Def, grades, cause, sx, ix, mx
Haemorrhoids are a pathological condition where the vascular cushions within the anal canal abnormally expand and can protrude outside the anal canal.
They are graded as below:
• Grade 1 - no prolapse
• Grade 2 - prolapse on straining which spontaneously reduces
• Grade 3 - prolapse on straining and require manual reduction
• Grade 4 - prolapse on straining and can’t be manually reduced, external haemorrhoids, or lower grade haemorrhoids failing to respond to less invasive measures
Cause:
• Constipation
• Pregnancy
• Increased intra-abdominal pressure due to causes like obesity, chronic cough or space-occupying lesions
• Portal hypertension, particularly secondary to cirrhosis, due to increased pressure at the rectal porto-systemic anastomosis
Sx:
• Bright red PR bleeding, often associated with defecation and on wiping
• Absence of pain, unless the patient has a thrombosed external haemorrhoid or another condition such as an anal fissure
• Anal pruritus
• A palpable or protruding mass in the anal region during examination, suggestive of prolapsing haemorrhoids
Ix:
- PR exam
- anoscopic exam
Mx:
• Grade 1: Conservative management, including potential use of topical corticosteroids to alleviate pruritus
• Grade 2: Management may involve rubber band ligation (preferred), sclerotherapy, or infrared photocoagulation
• Grade 3: Rubber band ligation is the treatment of choice
• Grade 4: Surgical haemorrhoidectomy may be necessary In all cases, patients should be advised to maintain a diet rich in fibre and fluids to reduce the risk of constipation, thereby limiting exacerbation of haemorrhoids.
For thrombosed haemorrhoids, which present as painful, purple protrusions, conservative measures such as ice packs, laxatives, and lidocaine gel are first-line treatments. If these measures fail, haemorrhoidectomy may be required.
Perianal abscesses and fistulae
Def, causes, sx, ix, mx
An anorectal abscess is a localized collection of pus in the perianal or rectal spaces, commonly arising from an infection in the anal glands.
Causes:
- anal fistulae (connections between surface of anal canal and external skin)
- Crohn’s
Sx:
- perianal pain
- perianal swelling
- systemic (pyrexia, tachycardia and potentially sepsis if there is spread)
Ix:
- PR exam
- FBC, CRP, ESR and flood cultures
- MRI pelvis is gold standard
Mx:
- drainage under local
- incision and drainage under general when degree of tissue damage is unknown or in the case of a deep perirectal abscess with sphincter extension
- antibiotics if underlying diabetes or immunosuppression. IV if presentation is already septic
Colorectal cancer
Rf, sx, staging, screening, ix, mx
Rf:
- age
- FAP (familial adenomatous polyposis)
- lynch syndrome
- juvenile polyposis
- peutz-jeghers syndrome
- alcohol
- tobacco
- processed meat
- obesity
- radiation
- IBD
Sx:
- rectal bleeding
- weight loss
- change in bowel habit
- abdo pain
- iron deficiency anaemia
- bowel obstruction resulting in nausea and vomiting
Staging:
TNM (tumour, node, metastases) is a more recent classification system (replacing the Duke’s classification), which provides a more uniform classification of colorectal cancer.
• T: Tis (carcinoma in situ/intramucosal cancer), T1 (extends through the mucosa into the submucosa), T2 (extends through the submucosal into the muscularis), T3 (extends through the muscularis into the subserosa), T4 (extends into neighbouring organs or tissues).
• N: NO (no regional lymph node involvement), N1 (metastasis to 1-3 regional lymph nodes), N2 (metastasis to 4 or more regional lymph nodes).
• M: MO (no distant metastasis), M1 (distant metastasis).
Staging informs both the prognosis and the treatment plan.
Patients with Duke’s stage C or stage III (T1-4, N1-2, MO) colon cancer benefit from adjuvant chemotherapy. Note that patients without lymph node involvement but with high risk features (such as vascular or perineural invasion) also show improved survival with adjuvant chemotherapy.
Screening:
• Faecal immunochemical test (FIT) every 2 years for men and women age 60-74. If positive patients are referred for colonoscopy. >10
Ix:
• Bloods - FBC (anaemia), iron studies, and carcinoembryonic antigen (CEA) are useful initial investigations
• CEA is not used as a diagnostic tool but is a tumour marker that can be used to monitor therapeutic response to interventions.
• The gold standard investigation is a colonoscopy. It allows
• Direct visualisation of the colon
• Biopsies to be taken
• Removal of any polyps seen
• If colonoscopy cannot be performed, either due to technical difficulties, poor tolerance of bowel preparation or there is an increased risk of colonic perforation a CT colonoscopy is a suitable alternative but does not allow biopsy.
• After a histological diagnosis is made, a CT chest, abdomen and pelvis should be performed to stage the disease, so an appropriate intervention can be planned.
• In rectal disease, a pelvic MRI or endorectal ultrasound are preferred over
CT scan, as are better for identifying locally invasive disease.
Mx:
For patients with colon cancer suitable for surgery:
• Stage I-III disease: surgical resection ‡ adjuvant chemotherapy.
The type of surgery depends on the tumour site: right hemicolectomy for tumours of the caecum and ascending colon, left hemicolectomy for tumours of the distal transverse colon and descending colon, and sigmoid colectomy for tumours of the sigmoid colon.
• Stage IV disease (metastases): treatment is as above, but neoadjuvant chemotherapy may also be performed. The staged colectomy and resection of metastatic disease is performed after neoadjuvant chemotherapy.
• In terms of specific surgical procedures, patients with caecal and ascending colon tumours undergo right hemicolectomy
For patients with rectal cancer suitable for surgery:
• Anterior resection for tumours >8 cm from the anal canal or involving the proximal 2/3 of the rectum.
• Abdomino-perineal (AP) resection for tumours <8 cm from the anal canal or involving the distal 1/3 of the rectum.
• Patients with stage Ill disease benefit from adjuvant chemotherapy.
• Patients with stage IV disease benefit from adjuvant chemoradiotherapy
Diverticular disease
Def, rf, sx, ix, mx
Def:
- Diverticular disease is a term used to describe conditions related to the presence of diverticula, which are small, bulging pouches that can form in the lining of the digestive system, most commonly in the lower part of the colon (sigmoid colon).
- Diverticulosis refers to the simple presence of diverticula. In many cases, diverticulosis is asymptomatic, and individuals may not even be aware that they have these diverticula as they are typically discovered incidentally during tests for other conditions.
- Diverticulitis, a subset of diverticular disease, occurs when these diverticula become inflamed or infected. This condition is typically characterized by severe abdominal pain, fever, and nausea. Diverticulitis often requires treatment, which can include antibiotics, pain relievers, and, in severe cases, surgery.
Rf:
- age
- low fibre diet
- obesity
- lack of exercise
- NSAIDs
- opiates
Sx:
- constipation
- LLQ pain
- rectal bleeding
Diverticulitis sx:
- fever
- nausea/vomiting
- pyrexia
- guarding
- diffuse abdominal tenderness suggestive of peritonitis
Ix:
- CT or ultrasound
- bloods for inflammation
- colonoscopy or endoscopy
Mx:
- increase fibre and hydration
- analgesia
- antibiotics
- surgery for obstruction
- recurrence may need elective colectomy
