Gastroenterology Flashcards
What is the definition of Crohn’s disease?
Transmural, granulomatous inflammation of the GI tract
What is the aetiology of Crohn’s disease?
Autoimmune disease initiated by an inflammatory response to GI bacteria
What is the pathophysiology of Crohn’s disease?
Inflammatory infiltrate around intestinal crypts that subsequently develops into ulceration of the superficial mucosa. The inflammation progresses to involve deeper layers and forms non-caseating granulomas
What is the clinical presentation of Crohn’s disease?
Remissions and exacerbations, abdominal pain (lower right quadrant), prolonged diarrhoea with urgency, perianal disease (perianal abscesses, anal strictures)
What are the investigations of Crohn’s disease?
o CRP and ESR: elevated
o pANCA: negative
o Faecal calprotectin: elevated in inflammatory bowel disease
o Colonoscopy with biopsy: aphthous ulcers, hyperaemia (increased blood flow), oedema, cobblestone, skip lesions
What is the treatment of Crohn’s disease?
o Mild: controlled-release corticosteroids (budesonide) or exclusive enteral nutrition
o Moderate: glucocorticoids (oral prednisolone)
o Severe: IV hydrocortisone, with rectal disease treated using hydrocortisone per rectum and antibiotics for inflammation and abscesses
o Remission maintenance: azathioprine or methotrexate
o Surgery
What is the definition of ulcerative colitis?
Diffuse inflammation of the colonic mucosa
What is the aetiology of ulcerative colitis?
Inflammatory response to colonic bacteria, smoking is protective
What is the pathophysiology of ulcerative colitis?
Inflammation begins in the rectum and can progress along the colon as far as the ileocecal valve. The inflammation is circumferential and continuous, there are no skip lesions
What is the clinical presentation of ulcerative colitis?
Remitting and relapsing, rectal bleeding, diarrhoea, blood and mucus in stools
What are the investigations of ulcerative colitis?
o CRP and ESR: elevated
o pANCA: positive
o Faecal calprotectin: elevated in inflammatory bowel disease
o Colonoscopy with biopsy: continuous inflammation of colonic mucosa
What is the treatment of ulcerative colitis?
Aminosalicylates (sulfasalazine, mesalamine), azathioprine, colectomy
What is the definition of irritable bowel syndrome?
Abdominal pain associated with bowel dysfunction for which no organic cause can be found
What is the clinical presentation of irritable bowel syndrome?
Abdominal pain (lower abdomen pain which is typically cramping and relieved by defecation), bloating, changes in bowel habit
What are the investigations of irritable bowel syndrome?
o FBC: normal o CRP and ESR: inflammation o Coeliac serology: negative o Faecal calprotectin: negative o Colonoscopy: normal
What is the treatment of irritable bowel syndrome?
Lifestyle modifications, anti-spasmodics (buscopan), laxative, anti-motility (loperamide), amitriptyline
What is the definition of coeliac disease?
Systemic autoimmune disease triggered by dietary gluten peptides found in wheat, rye, barley, and related grains
What is the aetiology of coeliac disease?
HLA-DQ2
What is the pathophysiology of coeliac disease?
Gliadin can have direct toxic effects by up-regulating the innate immune system or HLADQ2 can present it to T helper cells in the lamina propria which leads to inflammation, villi atrophy, and malabsorption
What is the clinical presentation of coeliac disease?
Diarrhoea, weight loss, anaemia, steatorrhea, abdominal pain, fatigue and weakness, bloating, nausea and vomiting, oral aphthous ulcers, angular stomatitis
What are the investigations of coeliac disease?
o FBC: anaemia (iron deficiency)
o IgA tissue transglutaminase antibody (tTGA): positive (more specific)
o IgA endomysia antibody (EMA): positive
o Duodenal biopsy: villous atrophy, crypt hyperplasia, increased epithelial white blood cells
What is the treatment of coeliac disease?
Life-long gluten free diet
What is the definition of gastroesophageal reflux disease?
Symptoms or complications resulting from the reflux of gastric contents into the oesophagus or beyond
What is the aetiology of gastroesophageal reflux disease?
Oesophageal sphincter relaxation (lower oesophageal sphincter hypotension, a hiatus hernia, loss of oesophageal peristaltic function, abdominal obesity, gastric acid hypersecretion, slow gastric emptying, overeating, smoking, alcohol, pregnancy, drugs, and systemic sclerosis)
What is the clinical presentation of gastroesophageal reflux disease?
Heartburn (after meals which is aggravated by bending, stooping, and lying down), acid and food regurgitation
What are the investigations of gastroesophageal reflux disease?
o PPI trail: symptoms improve
o Endoscopy: oesophagitis (erosion, ulceration, strictures) or Barrett’s oesophagus (may be normal)
o pH monitoring: pH < 4 more than 4% of the time
What is the treatment of gastroesophageal reflux disease?
Lifestyle modifications, antacids, alginates (Gaviscon), PPI (lansoprazole), H2 receptor antagonists (cimetidine), surgery
What is the definition of peptic ulcer disease?
A break in the mucosal lining of the stomach or duodenum more than
5 mm in diameter, with depth to the submucosa
What is the aetiology of peptic ulcer disease?
Helicobacter pylori and the use of aspirin and NSAIDs
What is the pathophysiology of peptic ulcer disease?
Weakening or destruction of the mucosa
What is the clinical presentation of peptic ulcer disease?
Epigastric pain and tenderness with pointing sign
o Duodenal ulcer: pain is worse before meals and at night, and is relieved by eating or drinking milk
o Gastric ulcer: pain is worse on eating and relieved by antacid use
What are the investigations of peptic ulcer disease?
o Helicobacter pylori urea breath test or stool antigen test
o Upper GI endoscopy: peptic ulcer
What is the treatment of peptic ulcer disease?
Treatment of the underlying cause (NSAID cessation, Helicobacter pylori eradication), PPI (lansoprazole), H2 receptor antagonists (cimetidine)
What is the definition of appendicitis?
Acute inflammation of the vermiform appendix
What is the aetiology of appendicitis?
Obstruction of the lumen of the appendix
What is the clinical presentation of appendicitis?
Abdominal pain (originally periumbilical then migrates to the right iliac fossa), lower right quadrant tenderness with guarding (McBurney’s sign), anorexia
What are the investigations of appendicitis?
CT abdomen: inflamed appendix
What is the treatment of appendicitis?
IV antibiotics, appendicectomy
What is the definition of a small bowel obstruction?
Mechanical disruption in the patency of the gastrointestinal tract, resulting in a combination of emesis (that may be bilious), absolute constipation, and abdominal pain
What is the aetiology of a small bowel obstruction?
Adhesions, hernias, Crohn’s disease, intestinal malignancy, appendicitis, intussusception, intestinal atresia, volvulus
What is the clinical presentation of a small bowel obstruction?
Abdominal pain (initially colicky then diffuse), failure to pass flatus or stool, vomiting (occurs earlier in SBO compared to LBO), abdominal distention, abdominal tenderness, absolute constipation, peritonitis
What are the investigations of a small bowel obstruction?
o Abdominal X-ray: central gas shadows that completely cross the lumen, dilated intestinal loops, absence of gas in the rectum (in complete SBO), pneumoperitoneum
o Abdominal CT: extent and location of the obstruction
What is the treatment of a small bowel obstruction?
o Uncomplicated: conservative management (bowel decompression, fluid resuscitation, analgesia, anti-emetics, and antibiotics)
o Complicated: surgery
What is the definition of a large bowel obstruction?
Mechanical disruption in the patency of the gastrointestinal tract, resulting in a combination of emesis (that may be bilious), absolute constipation, and abdominal pain
What is the aetiology of a large bowel obstruction?
Colorectal malignancy, colonic volvulus
What is the clinical presentation of a large bowel obstruction?
Abdominal pain, failure to pass flatus or stool, vomiting (occurs later in LBO compared to SBO and may be absent), abdominal distention, abdominal tenderness, absolute constipation, peritonitis
What are the investigations of a large bowel obstruction?
o Abdominal X-ray – peripheral gas shadows proximal to blockage, caecum and ascending colon distention
o Abdominal CT: extent and location of the obstruction
What is the treatment of a large bowel obstruction?
o Uncomplicated: conservative management (bowel decompression, fluid resuscitation, analgesia, anti-emetics, and antibiotics)
o Malignancy: surgery
o Volvulus: flatus tube, surgery
What is the definition of intestinal ileus?
Slowing of gastrointestinal motility accompanied by distention, in the absence of a mechanical intestinal obstruction
What is the aetiology of intestinal ileus?
Post-operatively, acute or systemic illness, drugs, and multi-organ trauma.
What is the clinical presentation of intestinal ileus?
Nausea and vomiting, abdominal distention
What are the investigations of intestinal ileus?
o FBC: normal
o Abdominal X-ray: non-specific gas pattern, scattered air-fluid levels, diffuse small bowel distention
What is the treatment of intestinal ileus?
nil by mouth and IV fluids, non-opioid analgesia, chewing gum, nasogastric decompression
What is the definition of diverticulitis?
Acute inflammation and infection of diverticula
What is the aetiology of diverticulitis?
Low fibre diet
What is the pathophysiology of diverticulitis?
Herniation of the mucosa and submucosa through the muscular layer of the colonic wall. Inspissated food particles or faecal material may contribute to the development of infection, which when combined with increased intraluminal pressure, may cause inflammation, ischemia, and necrosis of the wall of a diverticulum, leading to perforation
What is the clinical presentation of diverticulitis?
Asymptomatic, abdominal pain and tenderness (left iliac fossa), fever
What are the investigations of diverticulitis?
o FBC: leukocytosis
o CRP and ESR: elevated
o CT abdomen and pelvis: colonic wall thickening, diverticular, pericolic collections and abscesses
What is the treatment of diverticulitis?
o Uncomplicated: well-balanced high fibre diet, anti-spasmodics
o Complicated: bowel rest, IV fluids and IV antibiotics, surgical resection
What is the definition of gastritis?
Gastric mucosal inflammation
What is the aetiology of gastritis?
Helicobacter pylori infection, NSAID or alcohol use/misuse, bile reflux, autoimmune atrophic gastritis
What is the clinical presentation of gastritis?
Asymptomatic, dyspepsia, epigastric discomfort
What are the investigations of gastritis?
o FBC: pernicious anaemia (in autoimmune atrophic gastritis)
o Helicobacter pylori urea breath test or stool antigen test
o Endoscopy: gastric erosions and atrophy
What is the treatment of gastritis?
Lifestyle modifications, treatment of the underlying cause (NSAID cessation, Helicobacter pylori eradication), PPI (lansoprazole), H2 receptor antagonists (cimetidine), vitamin B12 (autoimmune atrophic gastritis)
What is the definition of oesophageal varices?
Dilated collateral blood vessels in the oesophagus
What is the aetiology of oesophageal varices?
Portal hypertension (>10mmHg, rupture >12mmHg)
What is the clinical presentation of oesophageal varices?
Asymptomatic, haematemesis, melaena and rectal bleeding, abdominal pain, liver disease (jaundice, easy bruising, ascites), shock (hypotension, tachycardia), splenomegaly, pallor
What are the investigations of oesophageal varices?
o Serum LFTs – elevated transaminases, alkaline phosphatase, and bilirubin
o Endoscopy – dilated veins in the lower oesophagus
o Hepatic venous pressure gradient: elevated
What is the treatment of oesophageal varices?
o Acute: IV Terlipressin (vasoconstriction of the splanchnic artery)
o Long-term: variceal banding, beta blockers, nitrates
What is the definition of diarrhoea?
Abnormal passage of loose or liquid stools more than three times daily.
Acute diarrhoea is defined as that lasting less than 2 weeks, while chronic diarrhoea is defined as lasting more than 2 weeks.
What is the aetiology of diarrhoea?
o Dysentery: Shigella, Salmonella, Campylobacter, EHEC, Entamoeba histolytica, Clostridium difficile
o Non-dysentery: Norovirus, rotavirus
What is the pathophysiology of diarrhoea?
Decreased absorption or increased secretion of fluid and electrolytes, or increase in bowel motility
What is the clinical presentation of diarrhoea?
Diarrhoea, abdominal cramps, nausea, fever, fatigue, headache, bloating
What are the investigations of diarrhoea?
o FBC: raised WCC o CRP and ESR: elevated o Blood culture o Stool culture o PCR and enzyme immunoassay
What is the treatment of diarrhoea?
Treat the underlying cause, fluid resuscitation, anti-emetics (metoclopramide), anti-motility (loperamide)
What is the definition of ischaemic colitis?
Inflammation and injury of the large intestine due to inadequate blood supply
What is the aetiology of ischaemic colitis?
Thrombosis, emboli, low flow states, surgery, vasculitis, coagulation disorders, oral contraceptive pill, idiopathic
What is the clinical presentation of ischaemic colitis?
Sudden onset life iliac fossa pain, passage of bright red blood, hypovolaemic shock
What are the investigations of ischaemic colitis?
o CT: rule out perforation
o Flexible sigmoidoscopy with biopsy: epithelial cell apoptosis
o Colonoscopy with biopsy
What is the treatment of ischaemic colitis?
Fluid resuscitation, antibiotics, resection of necrotic bowel
What is the definition of mesenteric ischaemia?
Injury to the small intestine due to inadequate blood
What is the aetiology of mesenteric ischaemia?
Superior mesenteric artery thrombosis or embolism, mesenteric vein thrombosis, non-occlusive disease
What is the clinical presentation of mesenteric ischaemia?
Acute, severe abdominal pain (constant and central), no abdominal sounds on exam, rapid hypovolemia
What are the investigations of mesenteric ischaemia?
o Abdominal X-ray: exclude bowel obstruction
o Laparoscopy: visualise necrosis
o CT/MRI angiography: vessel occlusion
What is the treatment of mesenteric ischaemia?
Fluid resuscitation, antibiotics, IV heparin (reduce clotting), surgery to remove necrotic bowel
What is the definition of a Mallory Weiss tear?
Tear in the oesophageal mucosa
What is the aetiology of a Mallory Weiss tear?
Alcoholism, hyperemesis gravidarum, gastroenteritis, bulimia, chronic cough
What is the clinical presentation of a Mallory Weiss tear?
Haematemesis, melena, hypovolemic shock
What are the investigations of a Mallory Weiss tear?
Endoscopy: tear in the oesophageal mucosa
What is the treatment of a Mallory Weiss tear?
Usually self-limiting, Terlipressin (vasoconstriction), endoscopic banding/clipping
What are haemorrhoids?
Dilated and prolapsed anal cushion which presents with bright red rectal bleeding and discomfort
What are anal tags?
Polypoid projections of the anal mucosa and submucosa
What is an anal fissure?
Tear is the mucosa of the lower anal canal which presents with severe pain
What is an anorectal abscess?
Collection of pus within deep perianal tissue which presents with perianal erythema, swelling, and pain
What is an anorectal fistula?
Abnormal tract connecting the anal canal to the perinanal skin
