Revision List GI/Liver Flashcards
What is iron haemochromatosis?
Inherited disorder of iron metabolism leading to increased intestinal absorption so increased iron deposition in joints, liver, heart, pancreas, pituitary –> eventual fibrosis and organ failure.
AR
Cause of iron haemochromatosis?
- HFE gene mutation on chromosome 6 - AR
- High intake of iron/ chelating agents
- Alcoholics may have iron overload
What is hepicidin?
Regulates iron absorption - decreased in HFE mutation
Clinical presentation of haemochromatosis?
- Fatigue
- Joint pain
- Slate grey skin pigmentation, white flat nails
- Koilonychia
- Hepatomegaly, cirrhosis,
- Osteoporosis
- DM
- Skin dryness, melanoderma
Diagnosis of haematochromatosis?
Homozygous e.g. HFE genotyping
- increased serum ferritin, transferrin saturation, iron,
Liver biopsy for confirmation
Treatment of haematochromatosis?
Venesection - regular removal of blood - may regress fibrosis
Which part of the bowel tract does UC affect?
Only Colon
Which part of the bowel tract layer does UC affect?
Only mucosal inflammation
Which IBD is smoking protective in?
Ulcerative colitis
Risk factors for UC and Crohn’s?
- Fhx
- NSAIDs
- Chronic depression
- Stress
Clinical presentation of UC?
- Diarrhoea - often bloody and mucus
- Colicky LLQ pain
- Tenesmus
Pathophysiology of UC?
- Continuous mucosal inflammation spread from rectum to ileocaecal valve
- No granulomata
- Goblet cell decrease, crypt abscess increase
Clinical presentation of Crohn’s?
Colon: bloody mucus diarrhoea
Ileum - RIF
Small bowel - weight loss, abdominal pain
Extra GI symptoms: anorexia, tender abdomen, joint eye problems, oral ulcerations
Pathophysiology of Crohn’s?
- Transmural granulomatous inflammation –> epitheloid macrophages surrounded by lymphocytes
- Skip lesions
- Cobblestone mucosa
Diagnostic tests for IBD?
- Raised ESR, CRP, WCC and platelets
- Iron deficiency anaemia in UC
- Stool: exclude: campylobacter, c.diff, salmonella, shigella, E.coli
- Colonoscopy/ Sigmoidoscopy/ Rectal Biopsy:
- -> UC: inflammatory infilitrate, decreased goblet cells, mucosal ulcers
- -> Crohn’s spot lesion, granulomatous transmural inflammation - Faecal calprotein
Treatment for UC?
- Topical 5 aminosalicyclate - mesalazine
- Oral 5ASA - if remission not achieved
- Topical/ oral corticosteroid - prednisolone
- Calcineurin inhibitors
- Immunosuppresive - thioprine, methotrexate, TNF a inhibitor
Surgery for UC?
Colectomy - ileoanal anastomoses
Panproctocolectomy with ileostomy
Treatment for Crohn’s?
- Smoking stop
- iron/b12/folate anaemia - replacement therapy
- Monotherapy: conventional glucocorticoids ve.g. prednisolone, hydrocortisone
- Thiopurines: azathioprine add SE: bone marrow suppression, acute pancreatitis
- Anti-TNF Ab - immunosuppressive drug - influximab, adalimumab
Complications of Crohn’s?
Malabsorption –> small bowel obstruction
Anal skin tags, fissure, fistula
Systemic: colorectal cancer, amyloidosis, neoplasia
Irritable Bowel Syndrome
Relapsing functional disorder, change in bowel habits
Causes of IBS?
- Stress
- Eating disorders
- Depression
- GI infections
- Sexual/physical/verbal abuse
Clinical presentation of IBS?
- Abdominal symptoms: pain/discomfort - relieve by defecation linked to bowel frequency altered
Others: urgency, incomplete evacuation, abdominal distension/bloating, mucous in stools, worsen by food.
Non-intestinal: nocturia, back pain, joint hypermobility
Diagnosis of IBS?
- Bloods: anaemia, ESR, CRP raised
- Coeliac serology testing tissue transglutinase Ab
- Faecal calprotein - raised in IBD
Treatment of IBS?
- Mild IBS: education, reassurance, dietary modifications - frequent small meals, avoid alcohol
- Moderate IBS: pharmacotherapy, psychology Tx
- antispasmodic - mebeverine
Constipation: laxative e.g. mavicol; linaclotide, 5 HT4 receptor agonist
- Diarrhoea - anti-motility agents - loperamide
What are the 5 Fs? What do they indicate?
Someone presenting with RUQ –> fat/female/fair/fertile/forty = could be cholelithiases
What is peptic ulcer disease?
Break in epithelial lining of stomach/ duodenum –> penetrate muscularis mucosa
Where are gastric ulcers the most common?
Lesser curve of stomach
Where are duodenal ulcers most common?
Duodenal cap
What are the causes of peptic ulcer disease?
- Helicobacter pylori
- NSAIDs - steroids and SSRI too
- Excess acid secretion
- Delayed gastric emptying
- Smoking
How does mucosal ischaemia lead to ulcers?
- Atherosclerosis or decreased BP
- Decreased mucin production
- Damage –> ulcer
How do NSAIDs cause ulcers?
- NSAIDs are COX1/COX2 inhibitors and thus inhibit prostaglandin synthesis.
- Decreased mucus secretion
How does H. Pylori cause ulcer
- H. pylori inhibits mucus layer
- Decreased duodenal bicarbonate and increased acidiity
- Secretes urease to convert urea to ammonia + carbon dioxide.
- NH3 reacts with H+ to form ammonium which is toxic to the gastric mucosa
- Also secretes protease, phospholipase and vacuolating toxin A –> attack gastric epithelum –> decreased mucosal production
Clinical presentation of peptic ulcer disease?
- Recurrent burning epigastric pain - worse when hungry/night
- Nausea
Complications of PUD?
- Haemorrhage
- Peritonitis
- Pancreatitis
Lifestyle changes of PUD?
- Stop smoking
- Avoid stress
- Avoid irritating foods - caffeine/ spicy
- Stop NSAIDs
Helicobacter pylori Tx?
- 2 ABx + PPI
2. Clarithyromycin, metronidazole and omeprazole
What are the upper GI tumours you can get and which part of the tract do they affect?
- Oesophageal tumours
- Squamous cell carcinoma - middle and upper 1/3rd of oesophagus
- Adenocarcinoma - lower 1/3rd of oesophagus and cardia - Gastric tumours
- Adenocarcinoma
Investigations of PUD?
- Serology - detect IgG Ab
- C-urea breath test - measure CO2 in breath after ingesting urea
- Stool antigen test
- Endoscopy if - iron deficiency anaemia, weight decrease, persistent vomiting, epigastric mass
Aetiology of squamous cell carcinoma oesophageal tumours?
- High level of alcohol consumption
- Obesity –> increase reflux
- Decrease fruit and veg
- Smoking
What decreases the risk of oesophageal squamous cell carcinoma?
- Diet rich in fibres
- Carotene
- Folate
- Vitamin C
Aetiology/Causes of adenocarcinoma (oesophageal)?
- Smoking/tobacco
- GORD
- Obesity
- Barrett’s oesophagus
- Alcohol
How does oesophageal epithelium becomes neoplastic?
- Normal oesophageal squamous epithelium
- Metaplastic oesophageal glandular epithelium
- Dysplastic oesophageal glandular epithelium
- Neoplastic oesophageal glandular epithelium
Clinical presentation of adenocarcinoma of oesophageal epithelium?
- Progressive dysphagia - hoarse, cough
- Weight loss
- Lymphadenopathy
- Anorexia/ oesophageal obstruction
Diagnosis of oesophageal adenocarcinoma?
- Oesophagoscopy with biopsy
- Barium swallow
- CT/MRI/PET
Treatment of oesophageal adenocarcinoma?
- Surgical resection +/- chemo/radio
2. Treatment of dysphagia: endoscopy insertion of expanding metal stent
Main causes of gastric adenocarcinoma?
- Smoking
- H. pylori
- Decrease p53/APC gene
- Pernicious anaemia
Two major types of gastric tumours?
- Type 1: intestinal
2. Type 2: Difffuse
What is the Type 1: intestinal tumour?
Intestinal metaplasia in mucosa surrounding tumour - polypoid/ulcerating lesions
–> more likely to involve distal stomach.
Type 2: diffuse tumour?
Poorly cohesive undifferentiated cells –> infiltrate gastric wall –> can affect any part of cardia –> worse prognosis
Clinical presentation of gastric tumours?
- Epigastric pain - indistinguishable from PUD, pain = constant and severe
- Nausea/vomiting
- Anorexia/Weight loss
Diagnosis of gastric cancer?
- Gastroscopy and biopsy
- Endoscopic US
- CT/MRI for staging
- PET scan
Treatment of gastric tumours?
- Nutrition support
- Surgical resection + combination chemo
+post op radiotherapy
Combination chemo used for gastric tumour?
- Epirubicin
- Cisplatin
- 5-fluoro-uracil
What are the common small intestine tumours?
- Adenocarcinoma - 50%
2. Lymphoma
Clinical presentation of small intestine tumours?
- Pain, diarrhoea, anorexia, weight loss, anaemia, palpable mass
Diagnosis of small intestinal tumours?
- US
- Endoscopic biopsy
- CT scan
Treatment of small intestinal tumours?
- Surgical resection
2. Radiotherapy
What are colonic polyps?
Abnormal growth of tissue projects from colonic mucosa
What are adenomas?
Precursor lesions in most cases of colon cancer
Benign dysplastic tumour of columnar cells of glandular tissue.
What are two genetic linked colonic tumours?
- Familial adenomatous polyposis
2. Hereditary non-polyposis colon cancer
What is FAP?
AD mutation in APC gene where cysts form over teen years and can lead to cancer in 40s
What is HNPCC?
AD inheritance of hmSH1/hmSH2 mismatch repair gene mutations –> instability of DNA –> rapidly progressing colorectal carcinoma.
What is colorectal carcinoma?
Most commonly an adenocarcinoma
Risk factors of colorectal carcinoma?
- Smoking + alcohol
- Increase age
- Low fibre diet
- Animal fat and red meat consumption
- Sugar consumption
- Colorectal polyps