Gastrointestinal Flashcards
Coeliac Disease
Autoimmune T-cell mediated condition where exposure to gluten causes a reaction that causes inflammation in the small bowel.
Coeliac Disease Pathology
- Gluten broken into Gliadin
- Binds to IgA antibodies on gastric mucosa
- Gliadin- Antibody complex presents to transferrin receptor
- Complex endocytosed across gastric Mucosa into lamina propria
- Tissue Transglutaminase removes an amide
- Deaminated gliadin phagocytosed by HLADQ8/2 macrophages
- Macrophages signal chimune response causing inflamm.
Coeliac Disease Symptoms
Inflammation causes: Crypt hyperplasia + Lymphocyte infiltration + Villous atrophy
→ Malabsorption = steatorrhoea & diarrhoea
→ Iron deficiency anaemia
→ Weight loss
→ Fatigue
→ Mouth ulcers
→ Dermatitis herpetiformis = bumpy papular
Coeliac Disease investigations & management
Gluten= more than 1 meal per day
- Serology
1st Line = Total IgA + tTG + antigliadin + anti endomysial antibodies
Gold = duodenal biopsies - see villous atrophy, crypt hyperplasia, Raised intraepithelial lymphocytes
Management = Gluten free diet
Intestinal Obstruction Categories
→ Blockage
→ Pressure
→ Contraction
Intestinal obstruction Blockage causes
- Tumour
- Diaphragm disease - caused by NSAIDs
- Crohn’s = fibrosis - coarctation - obstruction
- Diverticular disease = Outpouching - faeces trapped
Intestinal obstruction Pressure causes
- Adhesions
- Volvulus - free floating areas with mesentery - Sigmoid
- Intussusception
Intestinal Obstruction Contraction causes
- Inflammation
- Intramural tumours
- Hirschsprung’s disease
Small bowel Obstruction Causes
Adults: Adhesions, Hernias, Crohn’s & Malignancy
Children: Volvulus, Intussusception, Hirschsprung ‘s, Appendicitis
Bowel obstruction Symptoms
- Vomiting
- Constipation/ Obstipation
- Abdo pain & Distension
- Tenesmus
- Weight loss
- Bowel sounds
Bowel obstruction signs
Perforation (peritonitis), Strangulation
Increased HR, Hypotension & High temp., Swelling
Bowel obstruction Investigations
- Digital Rectal Exam- large bowel
- X-Ray → Dilated jejunum / ileum, absense of gas distal to obstruction
- FBC + U&E
Bowel obstruction Treatment
- IV Fluids resus. (Nil by mouth)
- BoweI decompression
- Correct electrolyte imbalance
- Analgesia & anti - emetics
Definitions : Diverticulum Diverticulosis Diverticular Diverticulitis
Diverticulum = Outpouches Diverticulosis = asymptomatic condition of outpouches Diverticular = Symptomatic condition of outpouches Diverticulitis = Inflammation of outpouches
Diverticulosis Risk factors
- Low fibre diet
- NSAIDs
- COPD
- Old age
- Connective tissue disease
Diverticular /itis Symptoms & Investigations
- LLQ tenderness
- Constipation
- Rectal bleeding
- Fever
- Diarrhoea
Investigations = CT or Colonoscopy
Diverticulitis Complications
- Perforation
- Peritonitis
- Fistula
- Obstruction
Diverticular/ osis Treatment
Diverticulosis: High fibre diet
Diverticular:
- Bulk forming laxatives (Ispaghula husk)
- Surgery
Contraindications : Stimulants (sena)
Diverticulitis Treatment
Mild:
- 5 days of Co amoxiclav or Cephalexin with Metronidazole
- Analgesics (not opioids / NSAIDs)
- Liquid food
Severe:
- Nil by mouth
- IV Fluids & antibiotics
- CT & Surgery
Stages of Nutrition
I. Ingestion
- Digestion
- Absorption
- Egestion
Malabsorption Causes
- Intake
- Digestion = Pancreatic / bile secretion
- Absorption = Coeliac / Crohn’s - Villous atrophy
Malabsorption Symptoms
- Diarrhoea
- Steatorrhoea
- Weight loss
Malabsorption Complications
- Anaemia = low iron + Folate + B12
- Bleeding disorder = low vit. K
- Oedema = low protein
- Bone disease = low vit. D
→ Tropical spure
Diarrhoea causes
- Viral = Norovirus, Rota -virus
- Bacteria = Staph. Aureus, Salmonella
- Antibiotics - high risk of c.diff.
- Drugs (NSAIDs)
→ IBD & IBS
→ Bowel cancer
→ Hyperthyroidism
→ Stress
Antibiotics that cause c. diff
→ Clindamycin
→ Co-amoxiclav
→ Cephalosporins
→ Ciprofloxacin
Diarrhoea Red Flags
- Dehydration
- Renal failure
- Electrolyte imbalance
- Rectal bleeding, weight loss → cancer
Diarrhoea Investigations
- History
→ Floaty diarrhoea - Fat
→ Watery diarrhoea - Infection
→ Bloody diarrhoea - Inflammation / Cancer
- Stool test = culture + test for blood
- Blood test = culture + CRP (C - Reactive Protein)
Diarrhoea Treatment
- Fluid & Electrolyte replacement
- Antibiotics = Vancomycin
- Antimotility agents
- Antiemetics
IBS Types
→ IBS-D (Diarrhoea)
→ IBS-C (Constipation)
→ IBS-M (Mixed)
IBS Pathophysiology
- Stress
- Genetics
- Signalling
- Motility
IBS Symptoms
- Abdo pain & bloating relieved by defecation
- Mucus in stool
- Change in bowel habit - constipation, Straining
IBS Investigations
- Bloods
- ESR & CRP
- Coeliac Serology
IBS Treatment
Mild:
Education + Low fodmap diet + Reassurance
Moderate:
- Laxatives = Linaclotide or Bulk forming laxatives
- Anti- motility agents = Loperamide
- Antispasmodics
- CBT or Hypnotherapy
Severe:
TCA (Tricyclic Acids)
Ulcerative Colitis
Autoimmune Disease where there’s inflammation & uIceration of colon & rectum
Crohn’s Disease
Immune related.
Bacteria over stimulating immune system - Mainly affects ileum
Never affects rectum.
Crohn’s Disease Pathology
- Pathogens pass through Gl lining.
- Mutation allows pathogens through mucosa into deep Submucosa.
- Bacteria stimulates T- helper cells = releases cytokines = causes inflammation & granulomas = more cells = more cytokines = more inflammation