أسئلة الثامنة GIT الدلتا

• Ulcerative colitis is a chronic inflammatory condition affecting the rectum and extending proximally to involve a variable length of the colon.
• Males and females are equally affected.
• Peak onset age is between 20 to 40 years, with a second smaller peak in older adults.
• The etiology and pathogenesis are the same as Crohn's disease.

Intestinal Manifestations

• Symptoms of intestinal manifestations include bloody diarrhea and mucus per rectum.
• Patients commonly experience urgency of defecation and tenesmus.
• Abdominal pain occurs but is usually not as prominent as in Crohn's disease.
• Systemic symptoms are common in severe attacks, including anorexia, vomiting, fever, and symptoms of anemia.
• Signs of intestinal manifestations include a tender bowel on abdominal examination.
• Bowel sounds are normal unless in toxic megacolon.
• Signs of dehydration, fever, weight loss, and tachycardia can be seen in acute severe colitis.

Extraintestinal Manifestations

• Peripheral arthropathy, erythema nodosum, episcleritis, and aphthous (mouth) ulcers are related to the activity of colitis.
• Pyoderma gangrenosum and anterior uveitis are usually related to the activity of colitis.
• Sacroiliitis, ankylosing spondylitis, and primary sclerosing cholangitis are unrelated to the activity of colitis.
• Pericarditis and amyloidosis are rare extraintestinal manifestations.

Assessing Disease Severity

• The clinical criteria of Truelove and Witts are still used as a guide to decide on admission and IV therapy.
  • Mild UC involves < 4 bloody stools per day, with no systemic disturbance.
  • Moderate UC involves 4-6 bloody stools per day, with minimal systemic disturbance.
  • Severe UC involves > 6 bloody stools per day, with systemic disturbance (fever, tachycardia, anemia, or ESR/CRP >30).
• Markers of severity include:
  • High CRP
  • High platelets
  • Low albumin
  • Low Hb

Additional Notes

• Venous and arterial thromboembolic disease can result from hospitalization, immobility, malnutrition, increased platelet count, and clotting factors.
• Dermatological manifestations include aphthous stomatitis, erythema nodosum, psoriasis, and pyoderma gangrenosum.
• Ocular manifestations include uveitis, scleritis, and episcleritis.
• Vascular manifestations include portal hypertension, thromboembolism, thrombosis, and pulmonary embolism.
• Respiratory manifestations include obstructive sleep apnea and chest infections.
• Arthropathy includes arthritis, ankylosing spondylitis, and sacroiliitis.
• Hepatobiliary manifestations include primary sclerosing cholangitis, cirrhosis, colorectal cancer, and small-bowel cancer.
• Inflammatory manifestations include asthma, bronchitis, pericarditis, rheumatoid arthritis, and multiple sclerosis.
• Other manifestations include metabolic bone disease.

Pathology

• Distribution:
  • 50% involves the recto-sigmoid area.
  • 30% has left-sided disease (up to the splenic flexure).
  • 20% has pancolitis.
• Shortening and narrowing of the colon can occur due to chronic inflammation.
• Fibrosis and strictures are uncommon.
• Microscopic features include:
  • Inflammation confined to the mucosa
  • Crypt distortion (cryptitis, crypt abscess, crypt atrophy)
  • Irregular mucosal surface
  • Basal lymphoid aggregates
  • Chronic inflammatory infiltrate
  • Goblet cell depletion

Differential Diagnosis

• Crohn's disease
• Infective colitis
• Ischemic colitis
• Radiation colitis
• Microscopic colitis
• Drug-induced colitis (NSAIDs, antibiotics, and immune checkpoint inhibitor induced enterocolitis)

Laboratory Investigations

• CBC: Anemia, elevated WBC, and elevated platelets can be observed.
• High CRP is typically present.
• LFTs may show low serum albumin.
• Abnormal liver function and elevated alkaline phosphatase enzyme occur in primary sclerosing cholangitis (PSC).
• Stool tests:
  • Elevated fecal calprotectin or fecal lactoferrin can differentiate between IBD and IBS and can be used to follow up on response to treatment instead of colonoscopy.
  • Stool culture and sensitivity, Clostridioides difficile toxin, should be performed to exclude infectious colitis.
• Immunological markers:
  • pANCA is found in 70% of UC (only 15% of CD).
  • Antibodies to Saccharomyces cerevisiae (ASCA) are less common in UC than in CD.
• Common causes of high fecal calprotectin levels include Crohn's disease, ulcerative colitis, ischemia colitis, infectious colitis, and colorectal cancer.

Colonoscopy or Sigmoidoscopy

• Determine disease extent (proctitis, left-sided colitis, pancolitis) and severity (Mayo score).
• Take biopsies for histology.
• Take biopsies for Cytomegalovirus (CMV) histology in refractory or severe disease (inclusion bodies).
• Take biopsies for diagnosis of dysplasia and cancer.

Radiology

• Plain Abdominal X-Ray: To diagnose toxic megacolon (colon diameter ≥6 cm).
• Barium enema: Shows pipe stem appearance of the colon.
• Contrast CT (colography): Gives much more information and shows colonic wall thickening.
• Intestinal US: Can give information about some areas of the colon (including sigmoid and caecum).
• MRI (colography): Of the pelvis and abdomen to characterize colitis.

Surveillance for CRC in Ulcerative Colitis

• Longstanding ulcerative colitis is associated with an increased risk of colorectal cancer (CRC) (High-risk group).
• Patients should receive initial screening colonoscopy:
  • 8 years after the onset of pancolitis.
  • 12 to 15 years after the onset of left-sided disease.
• Follow-up colonoscopy should be repeated every two to three years.

Treatment of UC

• Proctitis treatment includes topical 5-amino-salicylic acid (5-ASA) (mesalazine) or steroid enemas, or a combination of both.
• Suppositories are effective for pure proctitis.
• If symptoms continue, add oral 5-ASA.

Mild or Moderately Active and Severe Colitis

• Use oral mesalazine, oral steroids in moderate dose (prednisolone 20mg/day).
• If relapses rapidly on tapering steroids, start 2nd line treatment with an immunosuppressive agent (azathioprine, 6-mercaptopurine).
• If persistent despite receiving steroids and immunosuppressive drugs, shift to biologic drugs (Infliximab, Vedolizumab, Adalimumab, Ustekinumab, or Tofacitinib) or surgery.

Maintenance Treatment

• Use mesalazine indefinitely at a dose of 1200-2400mg/day.

Surgery

• Indications for surgery in ulcerative colitis include:
  • Severe attacks not responding to medical therapy.
  • Complications of severe attack (perforation, acute megacolon).
  • Refractory chronic continuous disease with impaired quality of life.
  • Dysplasia or carcinoma.
• Choice of operation:
  • Total colectomy with permanent ileostomy.
  • Total colectomy with ileoanal pouch formation.
  • Colectomy with pouch formation is the operation of choice.