GI one

Dysphagia

• Dysphagia is difficulty in swallowing.
• A symptom of dysphagia is a sensation of something sticking in the throat or chest during or immediately after swallowing.

Oesophageal Causes of Dysphagia

• Tumours: Most commonly squamous cell carcinoma (SCC) or adenocarcinoma (lower 1/3 of oesophagus).
  • Gradual onset dysphagia, can spread to lymph nodes, may fungate into the lumen.
  • Local spread effects include tracheo-oesophageal fistulation and recurrent laryngeal nerve palsy.
• Inflammation: Can be caused by acid reflux, drugs, or chemical burns.
• Stricture: Can be caused by radiation or acid reflux.
• Foreign body:
  • Soft food bolus: can be treated with muscle relaxants.
  • Impacted coins (smooth): should be removed at earliest opportunity.
  • Bones (sharp): require emergency removal to avoid perforation of muscle wall.
• Trauma: Can be caused by bones or surgery.
• Web:
  • Mucosa becomes atrophic, and a fibrous stricture forms at the upper end of the oesophagus; pre-malignant.
  • Seen as a web on a barium swallow.
  • Consists of glossitis, iron deficiency anaemia, dysphagia, and koilonychia, especially in middle-aged women.
• Goitre, Enlarged Left Atrium, Mediastinal Glands
• Oesophageal spasms: Due to atypical achalasia, acid reflux, neuromuscular disorders, or cardia obstruction.
• Achalasia:
  • Loss of ganglia from intramural plexus leads to a failure of relaxation of the cardiac sphincter.
  • Obstructs oesophageal emptying, causing dysphagia for both solids and liquids.
  • Failure of peristalsis results in further dilation of the oesophagus.
  • Retained oesophageal contents may be regurgitated, causing respiratory problems.

Oral and Pharyngeal Causes of Dysphagia

• Tumours: Squamous cell carcinoma (SCC).
• Inflammation: Severe candidiasis, herpes, tonsillitis, glossitis.
• Fibrosis: Scleroderma (increased collagen, decreased elastin, microstomia, and fibrosis).
• Trauma: Can be caused by bones or surgery.
• Pouch:
  • Herniation of mucosa through the fibres of the inferior pharyngeal constrictor muscle (cricopharyngeus).
  • Forms a pulsion diverticulum that collects food and can regurgitate into the mouth/lungs at night, leading to secondary pneumonia.
  • Swelling in the lower neck, usually on the left side.
• Deformity of Cervical Spine
• Xerostomia: Sjogrens, drugs (e.g., tricyclic antidepressants or TCAs).
• Stroke
• Parkinson’s, MS, MG, Bulbar Palsy (motorneurone disease)
• Globus Hystericus:
  • Not true dysphagia; intermittent sensation of a lump in the throat.
  • Perceived to be in the midline at the level of the cricoid cartilage.
  • Worse when swallowing saliva, less obvious when ingesting food or liquids.

Symptoms of GI Disease

• Abdominal pain
• Dysphagia: Difficulty in swallowing.
• Heartburn: Retrosternal burning discomfort due to mainly acid reflux.
• Dyspepsia: Upper GI symptoms (nausea, heartburn, acidity, pain) - blanket term is ‘indigestion’.
• Flatulence: Excessive wind.
• Vomiting: Stimulation of the vomiting centres in the lateral reticular formation of the medulla.
• Constipation
• Diarrhoea
• Steatorrhoea: Passage of pale bulky stools that contain fat.

Oesophagus

• The oesophagus is a musclotendinous tube connecting the pharynx to the stomach.
• Symptoms of oesophageal issues include dysphagia, pain from acid reflux, cough or vomiting (reflux of food/liquids), and bleeding (haematemesis).
• Diseases associated with the oesophagus: Pharyngeal pouch, achalasia, oesophageal spasm, oesophageal web, peptic ulcer disease/reflux, and carcinoma.
• Muscles of the Oesophagus: Superior, middle, and inferior constrictor muscles.
• Weak Point: Meeting point of 2 parts of inferior constrictor is Killian’s dehiscence.
  • This can become a Zenker's Diverticulum.
• Muscle Layers: Inner circular and outer longitudinal muscle coats.
• Muscle Type: Upper 2/3 striated, lower 2/3 non-striated (middle 1/3 is mixed).
• Innervation: Motor and sensory nerves from the vagus nerve (X) via the oesophageal plexus.
• Epithelium: Lined with stratified squamous non-keratinizing epithelium.
• Swallowing: Peristaltic wave triggered, pushing food bolus to the stomach; gut stretches, causing depolarisation and action potentials that propagate waves of muscle relaxation and contraction.
• Cardiac Sphincter: Described as weak at the gastro-oesophageal junction.

Pharyngeal Pouch

• Herniation of mucosa through a weakness in the pharyngeal constrictor muscles.
• The pouch hangs down due to gravity.
• Symptoms include dysphagia, vomiting, respiratory symptoms, and the formation of Zeneker’s Diverticulum through Killian’s dehiscence.

Oesophagitis

• Main reason is inflammation of the oesophagus due to acidic reflux from the stomach.
• Candida oesophagitis arises in immunocompromised individuals (transplant, chemo, HIV infection).

Achalasia of the Cardia

• Loss of ganglia from the intramural plexus impairs relaxation of the gastro-oesophageal sphincter.
• A neuromuscular dysfunction where the cardiac sphincter fails to relax during swallowing.
• Results in functional obstruction to oesophageal emptying with dysphagia for solids and liquids.
• Failure of peristalsis leads to progressive dilatation of the oesophagus.
• Treatments: Drugs (nifedipine), balloon dilatation, and cardiomyotomy.

Oesophageal Spasm

• Spasm due to various causes resulting in attacks of dysphagia and pain.
• Causes: Atypical achalasia, gastro-oesophageal reflux, motor disorders, symptomatic peristalsis, obstruction at the cardia, and neuromuscular disorders.
• Potential result is a corkscrew oesophagus causing pain due to reflux and heartburn.
• Muscle relaxants can relieve spasms.

Oesophageal Web

• Consists of glossitis, iron deficiency anaemia, dysphagia, and koilonychia (spoon-shaped finger nails).
• Most commonly occurs in middle-aged women.
• Important to identify as it is premalignant.
• Barium swallow shows atrophic mucosa and a fibrous structure at the upper end of the oesophagus, forming a web.
• Treated with dilatation of the stricture, correction of iron deficiency, or excision.

Peptic Ulcer Disease/Relux

• Failure of the upper (cardiac) sphincter results in acid reflux into the oesophagus.
• Can cause pain, ulceration, and spasms.
• Aetiology Difference: Peptic is acidic; gastric can have any cause.
• Area Difference: Peptic affects oesophagus, stomach, or duodenum; gastric affects only the stomach.
• Common Aetiology: Mucosal inflammation is due to acid and pepsin destruction of lining mucosa; mucus protection coat is removed.
• Triggers: Aspirin/NSAIDs (block cyclooxygenase and prostaglandin production), steroids, smoking, and Helicobacter pylori infection.
• Dentists should avoid NSAID use; steroids may complicate.
• Acute vs. Chronic Duodenal Ulcer: Chronic penetrates submucosa and muscular wall; acute only reaches muscularis mucosae.
• Symptoms: Pain, vomiting, haematemesis, and ulcer with scarring.
• Scarring may lead to a stricture or obstruction.
• Scarring may heal leading to local scarring
• Scarring may lead to perforation of the gut wall, causing bleeding, peritonitis, and death.
• Diagnosis: Endoscopy and barium meal.
• Treatments: Control predisposing factors (antacids), decrease secretions (H-2 blockers like ranitidine or proton pump inhibitors like omeprazole), and treat H. pylori with quadruple therapy (PPI, bismuth, 2 antibiotics - amoxil and clarithromycin).

Gastritis

• Chronic inflammation/irritation can cause erosion, ulceration, bleeding, and malignant conversion.
• Inflammation reduces acid production (achlorhydria), reducing ferric to ferrous conversion of iron, risking iron deficiency (glossitis and microcytic anaemia).
• Inflammation reduces intrinsic factor production, impairing Vitamin B12 binding and reabsorption in the terminal ileum, leading to macrocytic anaemia and a sore mouth.
• Gastric parietal cell antibody production can mimic this.

Barrett’s Oesophagus

• Long-standing reflux from the stomach causes changes in the lower oesophageal lining.

Carcinoma of the Oesophagus

• Most common in people over 50.
• Risk increases with heavy alcohol use (20x), smoking (5x), food toxins, peptic disease, achalasia of the cardia, pharyngeal pouch, Fe deficiency (which can also cause an oesophageal web), and coeliac disease (from malabsorption).
• Symptoms include dysphagia (gradual onset, solids before liquids), and pain on swallowing.
• Local spread effects include fistulae to the trachea and damage to the recurrent laryngeal nerve resulting in a hoarse voice.
• Squamous cell carcinoma is the majority type; the carcinoma fungates into the lumen and then diffusely infiltrates adjacent structures like the mediastinum, lymph nodes, and the liver.
• Diagnosis: Barium swallow, endoscopy and biopsy, and CT scan (to stage and plan treatment).
• Treatments: Surgery (with a 5cm resection margin, dangerous but curative), radiotherapy (palliative), and stent.

Pyloric Stenosis

• Paediatric projectile vomiting due to the pyloric sphincter being closed.

Haematemesis

• Vomiting of blood that is usually partially digested, dark (coffee grounds), and mixed with food.
• Usually from the upper GI tract.
• Congenital Causes: Haemophilia, Ehlers-Danlos syndrome, Peutz-Jeghers syndrome.
• Infective Cause: Helicobacter pylori-induced ulceration.
• Inflammatory Causes: Peptic ulceration, gastritis, oesophagitis.
• Traumatic Causes: Surgery, swallowed blood from epistaxis, foreign body perforation, tear in oesophagus due to excessive vomiting.
• Venous Engorgement Cause: Oesophageal varices.
• Vascular Malformation Cause: Haemangioma.
• Neoplasia Causes: Oesophageal SCC, gastric carcinoma.
• Fistula Cause: Aorto-oesophageal fistula.
• Drug Induced Causes: Warfarin, NSAID induced gastric erosion/peptic ulceration.