Gastrointestinal Disorders 1

Gastritis

Inflammation of the gastric mucosa that can be either acute or chronic.

Age group:
  • Acute: 40-50 year olds
  • Chronic: over 60 year olds
Risks: helicobacter pylori infection, smoking/alcohol abuse/high caffeine, spicy food, aspirin and NSAID use (most common risk)

Acute Gastritis

Erosion of the surface epithelium where mucous barrier is broken down, exposing cells to the strong acidity of the gut.

Healing time: few days (due to high regeneration rate of cells)

Symptoms: epigastric pain and hematemesis

Chronic Gastritis

Produces scarring and involves atrophy of the gastrointestinal mucosa.

Characteristics: low no. of secretory cells, progressive and permanent thinning and degeneration of the gastric mucosa, decreased digestion of protein and decreased HCl, lack of intrinsic factor → pernicious anaemia

Result: can lead to gastric cancer (2 in 3 chance)

Hiatal Hernia

A hernia occurs when a portion of an organ pushes up, through or into an opening, e.g. a sphincter, bulging unnecessarily into a body cavity.
  1. Type 1 (sliding) hernia: 90% of cases, upward into the oesophagus
  2. Type 2 (rolling) hernia: 10% of cases, moves to the side of the oesophagus

Gastro-Oesophageal Reflux Disease (GERD)

This is reflux esophagitis, which is commonly accompanied by a hiatal hernia (see above).

Cause: refluxed acid, enzymes and bile acids

Result: inflammation, dysphagia (difficulty breathing), upper GI tract ulcers, bleeding, perforations and scarring, obstructive stricture (narrowing of GI tract), Barrett's metaplasia (metaplastic transformation from squamous to columnar cells - premalignant condition)

Risks: smoking, age, increased abdominal pressure, e.g. due to pregnancy, abnormal functioning of the lower oesophageal sphincter

Peptic Ulcer Disease (PUD)

A break or ulceration in the protective mucosal lining of the gut.

Site: oesophagus, stomach and duodenum (more common than gastric ulcers) → regions distal to duodenum not affected

Causes: helicobacter pylori, stress, alcohol and smoking

Diagnosis: carbon urea breath test to detect helicobacter pylori (using radioactive carbon isotope)

Intestinal Obstruction

Cause: any condition that prevents the normal flow of chime through the intestinal lumen

Symptoms: distention (swollen), copious vomiting, severe dehydration (causing hypovolemic shock), colicky intermittent pain (gas), severe pain

Result:
  • High small-bowel obstruction → metabolic alkalosis
  • Low small-bowel obstruction → metabolic acidosis
   1.   Hernia

A protrusion of the intestine through a weakness in the abdominal muscle or through the inguinal ring

   2.   Intussusception

When a segment of the bowel invaginates in on itself, with the outer segment swollen and congested and the inner tissue infarcted and congested.

   3.   Torsion (volvolus)

The twisting of the bowel, causing obstruction and blood vessel compression → gangrene, necrosis and perforation.

Age group: middle to elderly men

Site: caecum and sigmoid colon

   4.   Paralytic ileus

Loss of peristaltic motor activity in the intestine, e.g. due to abdominal surgery, peritonitis and ischemic bowel

   5.   Adhering bowel

Parts of the bowel abnormally adhere to one another due to inflammation

Inflammatory Bowel Disease

There are two conditions that fall under the heading of inflammatory bowel disease; crohn's disease and ulcerative colitis.

Crohn's Disease

Idiopathic inflammatory disorder with a slow progress anywhere in GI tract

Age group: any age but commonly 10-30

Gender: female

Characteristics: granulomatous (cobblestone appearance), stricture (tightening of lumen), adhesion formation/fistula, all layers of GI tract are affected (mostly submucosa), including entire intestinal wall, can skip areas of the bowel

Site: ileum, ileocecal area and proximal colon

Result: inflamed mesentery, enlarged lymph notes, fibrotic changes in smooth muscle and serosal layer, thickened and inflexible intestinal wall, granuloma uncommon (inflammation), intermittent diarrhoea, colicky pain, malabsorption and weight loss, malaise, fever, perianal abscess, intestinal obstruction, abdominal abscess

Ulcerative Colitis

Chronic, episodic and inflammatory disease of large intestine and rectum

Characteristics: melena (blood in stools), inflammation of mucosal layer, inflammation at base of crypts of Lieberkuhn (glands that secrete juices into intestine), begins in distal colon but can spread to entire colon, continuous throughout bowel, mucosal haemorrhage, necrosis and ulcerations, tongue like projections from mucosal layer

Result: abdominal pain, diarrhoea and rectal bleeding, intestinal cancer risk

Colorectal Cancer

  • 16% caecum and ascending colon
  • 8% transverse colon
  • 6% descending colon
  • 20% sigmoidal colon
  • 50% rectum
Colon cancer is present for a long time before producing symptoms.

Diagnosis: presence of CEA produced by colon cancer cells

Right-sided carcinoma


  • Bulky masses that protrude into the lumen
  • Dark stools
  • Weakness, malaise and weight loss
  • Older people and females
  • More advanced at diagnosis
  • Do not block flow of faeces
  • Survival of 19.4 months

Left-sided carcinoma (recto sigmoid carcinoma)

  • Constricting, 'napkin ring' growths
  • Bright red stools (bright red stools also indicate haemorrhoid)
  • Melena, diarrhoea and constipation
  • Survival of 33.3 months
The staging of colorectal cancer is summarised below:
  • 0 - carcinoma in situ with no nodal metastasis
  • Ⅰ - tumor confined to the mucosa with no nodal metastasis
  • Ⅱ - tumor penetrates all layers of the colonic wall
  • Ⅲ - any tumour not invading beyond colon or any tumour invading beyond colon, any or no nodal metastasis
  • Ⅳ - any tumour with or without metastasis

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