GI Flashcards
Hirschsprungs disease
No ganglion cells in myenteric plexus.
Obstruction in babies.
RET proto-oncogene Cr10+, assoc with Down’s.
Hypertrophied nerve fibres, no ganglia.
Tx: resect affected (constricted) segment.
Mechanical lower GI diseases
All obstruction:
- Constipation
- Diverticular disease
(Meckel’s = “true”, all layers, before 2yo. rule of 2s)
- Adhersions, external masses, herniation
- Intussusception, volvulus (small bowel in small children, sigmoid in ederly)
Diverticular disease
V common due to low fibre diet, high pressure.
90% in left colon.
Often ASx, ?PR bleed.
Complications: diverticulitis, perf, fistula, obstruction.
Inflammatory Bowel Disease
20s, White, Unknown aetiology. Extra-GI: - Malabsorption: Fe def, stomatitis; - Eyes: Uveitis, conjunctivitis; - Skin: pyoderma gangrenosum, erythema nodosum (tender); - Joints - Liver: pericholangitis, PSC.
Crohn’s disease
Smoking makes it worse.
Whole GI tract, whole thickness (transmural), skip lesions, Cobblestone. Aphthous ulcer, rosethorn ulcers. Non-caseating granulomata.
Intermittent diarrhoea (no blood), fever, pain.
Strictures, fitulae, abscesses, perforation.
Ix: CRP, ESR, Barium contrast, Endoscopy.
Mx: Pred / IV hydrocortisone / metronidazole. ?immunosupressors.
Ulverative Colitis
Starts in rectum, spreads continuously, doesn’t reach small bowel (unless backwash ileitis). Superficial, no structural problems other than pseudopolyps.
Bloody diarrhoea. mucus, pain relieved by defaecation.
Sever haemorrhage, toxic megacolon, ?adenoCa.
Ix: rectal biopsy, AXR, stool culture.
Tx: Pred + mesalazine.
Carcinoid syndrome
Diverse group of tumours of enterochromaffin cell origin. Usually bowel.
Produce Serotonin, so get carcinoid syndrome.
Bronchoconstriction, flushing, diarrhoea.
Ix: 24hr urine 5-HIAA.
Tx: Octreotide.
Adenoma of colon / rectum
Benign dysplasia, may become adenoCa.
50% >50yo have them, mainly asymptomatic.
Malingnancy RF: large, dysplastic, villous.
Peutz-Jeghers syndrome
Dominant, LKB1.
Multiple GI polyps, freckles around mouth, palms and soles.
More intussusception and malignancy, so watch GI tract.
Colon cancer
98% adenoCa. 60-79yo. (Familial if
Duke’s staging
Colon cancer. A : mucosa (>95% % year survival) B1 : muscularis propria B2: transmural C1 : muscularis propria + LN C2: transmural + LN D : distant metastases (
GORD
Commonest cause of oesophagitis.
Ulceration, haemorrhage, Barrett’s, stricture, perforation.
Los Angeles classification.
Tx: weight, stop smoking, PPIs.
Barrett’s oesophagus
After chronic GORD, columnar epithelium moves up.
10% symptomatic GORD become this.
30x risk of adenoCa.
Tx: endoscopic resection.
Oesophageal adenoCa
Common.
RF: smoking, obesity, radiotherapy, male.
Usually distal 1/3 because assoc with Barrett’s.
Squamous cell oesophageal Ca
Much rarer.
RF: Alcohol, smoking, Afrocab, achalasia of cardia, Plummer-Vinson syndrome, nutritional def, HPV.
Middle 1/3.
Progressive dysphagia, odynophagia, anorexia, weight loss.
Rapid growth, early spread, palliate.
Gastritis
Acute (neut): insult - aspirin, NSAIDs, bleach, burns.
Chronic (lymphocytes): H pyori, autoimm, alcohol, smoking.
Can give ulcers, or intestinal metaplasia then dysplasia then cancer.
Gastric ulcer
After antral gastritis (H pylori).
Epigastric pain worse with food.
RF: H pylori, smoking, NSAIDs, stress, elderly.
Punched out lesion with rolled margins.
Iron deficiency anaemia, perf, malignancy.
Gatric lymphoma
H pylori again!
#Haem
PPI, clarithromycin, amoxicillin.
Duodenal ulcer
4x more common than gastric.
Pain, worse at night, better with food and milk.
Younger adults.
Same RF: H pylori, smoking, NSAIDs, steroids.
Same complications: IDA and perf.
Coeliac disease
Autoimmune.
Gluten intolerance, villous atrophy, malabsorption.
Irish women.
Sx: steatorrhea, pain, bloating, N+V, weight loss/FTT, fatigue, IDA, rash (dermatitis hepatitis).
Tests: anti-endomysial, anti-TTG.
Best Ix: duodenal biopsy - villous atrophy.
Tx: gluten free diet.
10% progress to duodenal T-cell lymphoma if not treated.
