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Flashcards in Gastroenterology Deck (71)
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What are the pathological features of Crohn's disease?

Chronic inflammatory condition affecting the mouth - anus. Can have skip lesions.
Has a tendency to affect the terminal ileum and ascending colon.

Transmural with lymphoid hyperplasia and non-caseating granulomas.

Bowel appears thickened and narrow, with deep fissures and a cobblestone affect.
Associated with fistulae and abscesses


What are the extra-intestinal signs of Crohn's?

Eyes - uveitis, episcleritis
Joints - arthraliga, ankolysising spondylitis, inflmmatory back pain,
Skin - erythema nodosum, pyoderma gangrenosum
Liver and biliary tree - primary sclerosing cholangitis, fatty liver, chronic hepatitis, cirrhosis, gall stones.
Renal stones
osteomalacia, malnutrition, amyloidosis.


Which two genes are associated with an increased risk of developing Crohn's?

NOD2 - on chromosome 16 = intracellular sensor of bacterial peptidoglycan.
CARD15 - colon involvement is increased with this mutation expressed in macrophages and intestinal epithelial cells.


What are some of the therapies to treat Crohn's disease?

Steriods - for milk disease or acute attacks
Azathioprine - good steroid sparing agent
Elemental diets - mixing of single amino acids are antigen free.
Methotrexate - steroid sparing. Give once a week
TNF alpha inhibitors - can decrease disease progression.


What are the pathological features of ulcerative colitis?

Inflammatory disorder of the colonic mucosa - extends proximally from the rectum into the colon, and does not affect the the ileum apart from in back wash ileutis.

Hyperaemic granular mucosa with pseudo polyps. Only the mucosa is affected, it does not extend deep to the lamina propria.

On biopsy: goblet cell depletion, glandular distortion, mucosal ulcers, crypt abcesses.


What parameters are used to assess the severity of UC?
Describe what classes as severe disease.

Motions/day, rectal bleeding, temp at 6am, PR, Hb, ESR.

>6 motions a day, large amounts of rectal bleeding, temp 37.8, HR > 90, Hb 10.5, ESR > 30mm/h


What is the risk of developing cancer in UC?

15% with pancolitis for 20yrs - surveillance colonoscopy is carried out.


Describe the management of a person with UC.

Topical 5-aminosalyclic acid is the mainstay (sulfasalazine etc).

Proctitis - rectal 5ASA
Left sided colitis - 5ASA enemas, oral 5ASA and oral pred
Extensive colitis - 5ASA oral, 5ASA enemas,
Severe colitis - IV hydrocortiosone.

Ciclosporin and TNF alpha inhibitors can also help



What are the causes of hepatomegaly?

Malignant: metastatic or primary
Hepatic congestion: R heart failure, hepatic vein obstruction (Budd - Chiari syndrome)
Anatomical: Riedel's lobe
Infection: Glandular fever, hepatitis, malaria, schistosomiasis, amoebic abscess, hydatid cyst.
Haematological: leukaemia, lymphoma, myeloproliferative disorders, sickle cell, haemolytic anaemias,
Others: fatty liver, early cirrhosis, porphyria amyloidosis, Gaucher's disease


What are the causes of dysphagia?

Mechanical block ( difficult to swallow solids before liquids)
Lymph nodes
Enlarged left atrium
Lung cancer
Thoracic aneurysms
Pharyngeal pouch
Foreign body
Oesophageal web

Motility disorders (difficult to swallow liquids and solids intermittently)
Diffuse oesophageal spasm
Systemic sclerosis
Bulbar palsy
Psudobulbar palsy
Bulbar polymyelitis
Chagas' disease


What is achalasia?

a condition where the lower oesophageal sphincter fails to relax due to disruption of the myenteric plexus.
On barium swallow a characteristic dilated oesophagus is seen with the tapering end.


Describe the three types of oesophageal diverticulum:

1. immediately above the upper oesophageal sphincter = pharyngeal pouch
2. near the middle of the oesophagus due to inflammation
3. just above the lower oesophageal sphincter - epiphrenic diverticulum associated with achalasia.


How is swallowing mediated?

Centre in the dorsal motor nucleus of the X cranial n.

Inhibition followed by excitation results in initial relaxation followed by distally progressive activation of neurones to the muscle.

Primary peristalsis mediated by swallowing reflex.
Secondary peristalsis is mediated by food bolus stimulating infra oesophageal reflex.


What is the muscle content of the oesophagus?

upper 1/3 is striated muscle, circular and longitudinal layers

lower 2/3 is smooth muscle, longitude and circular layers


Name factors that predispose patients to getting GORD.

Hiatus hernia
lower oesophageal sphincter hypotension
loss of oesophageal peristaltic function
abdominal obesity
gastric acid hyper secretion
delayed gastric emptying
over eating
surgery in achalasia
drugs (TCAs, anticholingerics, nitrates)
systemic sclerosis
H. pylori


What are some of the extra oesophageal symptoms of GORD?

nocturnal asthma, chronic cough, hoarseness and throat clearing, sinusitis


What are the complications to GORD?

Oesphagitis, ulcers, benign stricture, Barrett's oesophagus, oesophageal adenocarcinoma, iron deficiency anaemia


When do you need to do an upper GI endoscopy for GORD

Age >55yrs, symptoms >4weeks, dysphagia, persistent symptoms despite treatment, relapsing symptoms, weight loss.


What are the 4 grades of GORD according to the Los Angeles classification?

1. >1 mucosal break 5mm long limited to the space between 2 mucosal fold tops
3. Mucosal break continuous between the tops of 2 or more mucosal folds but which involves less than 75% of the oesophageal circumference.
4. mucosal break involving >75% of the oesophageal circumference


What is Barrett's oesophagus?

A condition where the columnar epithelium extends upwards from the stomach to replace the squamous epithelium in the oesophagus. The squamocolumnar junction moves upwards.
Occurs in chronic oesophagitis.
Metaplasia can occur in the cells - 40 fold increase of developing oesophageal adenocarcinoma.


What is the management of no or low grade dysplasia Barrett's oesophagus?

Surveillance - strict PPI regime, can use endoscopic radio ablation or photodynamic therapy as well.


What is the management of high grade dysplasia Barrett's oesophagus?

Oesophagectomy or endosopic ablation or mucosal resection (if isolated regions)


What are the common and rare causes of upper GI bleed?

Peptic ulcers
Mallory weiss tear
Oesophageal varices
Drugs - NSAIDs, aspirin, steroids, thrombolytics, anticoagulants
Oesophagitis/ duodenitis
No obvious cause

Bleeding disorders
Portal hypertensive gastropathy
Aorto -enteric fistula
Dieulafoy lesions - rupture of an unusually large arteriole in the gastric fundas
Peutz- Jeghers'syndrome
Olser -Weber -Rendu syndrome


What is the scoring system used to risk score upper GI bleeds and what are its criteria?

Rockall score:

Pre endoscopy:
Age 60 - 79 = 1 point 80 = 2 points
Systolic and HR >100mgHg + 100 mmHg and >100 bpm = 1 point,


What initial rockall score is an indication for surgery?

the pre endoscopy score is a better predictor of mortality and rebleed.


What is the acute management of an upper GI bleed?

Protect airway and give high flow oxygen
Insert 2 large bore cannula and take FBC, U&Es, FBC, clotting, and cross match
Give IV fluids
Insert catheter and monitor urine output
organise CXR, ECG and ABG
Consider CVP line to monitor and guide fluid replacement
Transfuse with blood until hameodynamically stable
Correct clotting abnormalities
Monitor pulse, bp CVP hourly until stable
arrange urgent endoscopy
calculate rockall score

IV omeprazole should be given post endoscopy


What are the causes of chronic pancreatitis?

idiopathic (30%),
gall stones (in less than 25%)
pancreatic duct strictures,
pancreatic trauma,
hereditary (mutations of gene for cationic trypsinogen on Chr 7)
Recurrent acute pancreatitis
Congenital pancreas divisum (V RARE!)
Autoimmune - sjogrens, primary biliary cirrhosis, renal tubular acidosis
Hyperlipideamia, hypercalcaemia, hyperPTH, ureamia


What are the symptoms and signs of chronic pancreatitis?

Epigastric pain that radiates/ bores into the back ++++. bloating, steatorrhoea, wt loss, diabetes (30-40%)

on xray or USS - calcification in the pancreas supports the diagnosis


How do you manage chronic pancreatitis?

low fat diet, alcohol abstinence
Pancreatic enzymes to improve steatorrhoea
Coeliac plexus blockade may be needed for pain control

Surgically: ERCP - stenting, pancreaticojejunostomy, if total pancreatectomy is carried out, consider autotransplant of islets to reduce chance of brittle diabetes.


What are the causes of obstructive jaundice?

Common - CBD stones, carcinoma of the head of the pancreas, malignant porta hepatis lymph nodes

Less frequent - ampullary carcinoma, pancreatitis, liver secondaries

Rare - benign strictures, recurrent cholangitis, Mirrizi's syndrome ( gall stone stuck in the cystic duct causing compression of the CBD) sclerosing cholangitis, cholangiocarcinoma, biliary atresia, choledochal cysts. ?