Review posters 12/05/2016

Question 1

AST

Answer 1

aspartate amino transferase

Question 2

It what situations does AST become raised?

Answer 2

In acute liver injury. However it also becomes raised in heart and muscle.

Question 3

ALT

Answer 3

Alanine aminotransferase

Question 4

In what situations is ALT raised?

Answer 4

Acute liver cell injury

Specific to the liver

Question 5

Describe the relationship between ALT and AST

Answer 5

If both ALT and AST are raised- liver injury.

If just AST is raised- likely to be heart or muscle

Question 6

ALP

Answer 6

Alkaline Phosphatase

Question 7

In what situations is ALP raised

Answer 7

Generally raised in biliary tree damage and in certain bone cancers

Question 8

GGT

Answer 8

Gamma glutamyl transferase

Question 9

In what situations is GGT raised?

Answer 9

GGT specific to the liver/biliary tree

Question 10

Describe the relationship between ALP and GGT

Answer 10

If both GGT and ALP are raised- liver/biliary tree

If only ALP- somewhere else

Question 11

Albumin

Answer 11

Raised in chronic liver damage

Question 12

Prothrombin time

Answer 12

Time it takes for blood to clot. Clotting factors are produced by hepatocytes and will not be produced in liver damage.
It is the first thing to show in liver injury

Question 13

In what other situations can PTT be raised

Answer 13

Use of blood thinner e.g. aspirin and potassium vitamins.

Question 14

What percentage of a persons weight is water?

Answer 14

60%

Question 15

The fluid inside the body is made up of:

Answer 15

Extracellular fluid and intracellular fluid

Question 16

Extracellular fluid is made up of:

Answer 16

Plasma fluid and interstitial fluid

Question 17

How can extracellular fluid control MAP

Answer 17

If there is a drop in plasma volume, fluid from the interstitium will move across to counteract this.

Question 18

Which hormones help to regulate plasma volume and hence MAP

Answer 18

Anti-Natriuretic Peptide (ANP)
The Renin-angiotensin-aldosterone-system
Anti-diuretic hormone (ADH)

Question 19

Describe the Renin-Angiotensin-Aldosterone system

Answer 19

The kidneys (juxtaglomerular complex) produce renin. The Renin then goes on to activate angiotensinogen (produced by the liver) to form angiotensin I. Angiotensin I is then converted to angiotensin II by ACE. Angiotensin II stimulates the cerebral cortex to produce aldosterone.

Question 20

What effects does aldosterone have on the body?

Answer 20

It causes vasoconstriction, thirst and ADH release to increase blood pressure.

Question 21

When does renin get released?

Answer 21

When the renal pressure is low
When the Na+ concentration is low
Stimulation of renal sympathetic nerves

Question 22

When is ANP released?

Answer 22

Released in response to atrial dilation by atrial muscle cells.

Question 23

What does ANP cause?

Answer 23

Causes excretion of salt and water in the kidneys
Vasodilates
Decreases renin release

Question 24

When is ADH released?

Answer 24

Stimulated by reduced extracellular volume or an increase in extracellular osmolarity

Question 25

Where is ADH synthesised and stored?

Answer 25

Synthesised by the hypothalamous, stored in the posterior pitautry

Question 26

What does ADH cause?

Answer 26

Kidney tubules to increase the reabsorbtion of water | Vasoconstriction

Question 27

ADME

Answer 27

Absorption- Drug getting into the systemic circulation Distribution- Drug leaving the systemic circulation and entering the tissues Metabolism- converting the drug to its more polar form Excretion- excreting the drug from the body

Question 28

Oral availability

Answer 28

The fraction of the drug that gets into the systemic circulation after being ingested

Question 29

Systemic availability

Answer 29

The fraction of the drug reaching the systemic circulation after absorption

Question 30

First pass metabolism

Answer 30

Drugs administered orally can undergo first pass metabolism. This is where they get deactivated by the liver or brush border enzymes before reaching the systemic circulation.

Question 31

Factors affecting drug absorption

Answer 31

Solubility- has to be able to dissolve Chemical stability- some drugs may become inactivated by the stomach acid Lipid to water partition co-efficient- the more lipid soluble a drug is- increased rate of diffusion Degree of ionisation

Question 32

What is the degree of ionisation?

Answer 32

Only unionised forms of drugs will be absorbed. This depends on the pKa. pka=pH when 50% of the drug is ionised and 50% is unionised

Question 33

Name some trends with acids/bases and absorption

Answer 33

Weak acids and weak bases get absorbed more readily than strong acids and strong bases. Weak acids get absorbed in the stomach (the acidic environment with an acidic drug means it will not become ionised) whereas weak bases are more likely to be absorbed in the small intestine

Question 34

Bound drugs can move between body compartments. True or false.

Answer 34

False- bound drugs cannot move between body compartments

Question 35

Unionised drugs can move between the interstitial water and fat. True or false.

Answer 35

True

Question 36

Both unionised and ionised drugs can move between the interstitial water and plasma water. True or false.

Answer 36

True.

Question 37

Which routes of taking in drugs go through the liver.

Answer 37

Oral and (sometimes) rectal

Question 38

Which routes bypass the portal system and go straight into the systemic system?

Answer 38

Sublingual, intramuscularly, transdermal, inhalation and I.v. Sometimes rectal also.

Question 39

Pathological findings of Crohns

Answer 39

SKIP LESIONS Crypt abscesses- walled off pocket of space forms an abscess. If this were to become infected it would cause a slight fever. However if it were to rupture it would cause peritonitis Fistula- transmural inflammation goes through one area of bowel and starts to work its way into another. Could also occur between the bowel and the bladder.

Question 40

Pathological findings of Ulcerative Colitis

Answer 40

MUCOSAL/SUBMUCOSAL INFLAMMATION Crypt abscesses also form in UC. Psuedopolyps- raised area of inflamed tissue that look like polyps

Question 41

Why do you get inflammation in Crohns and UC?

Answer 41

Macrophages and neutrophils attack the intestinal wall

Question 42

Treatment of UC and Crohns

Answer 42

Mild/moderate- 5 aminosalicylic acid e.g. Mesalazine Anti TNF therapy Severe- corticosteroids e.g. prednisolone

Question 43

Treatment of UC and Crohns during relapses

Answer 43

Prophylactic antibiotics are used

Question 44

Symptoms of Crohns

Answer 44

Commonly affects the terminal ileum and large colon. RLQ (terminal ileum)- Abdominal pain, diarrhoea, weight loss, fatigue. Colon- diarrhoea +/- blood, fever

Question 45

Symptoms of ulcerative colitis

Answer 45

Colon- crampy left iliac fossa pain | Diarrhoea- often bloody

Question 46

Extra intestinal features of UC

Answer 46

Joint pain, erythema nodosum, liver disease

Question 47

Tests for UC and Crohns

Answer 47

Raised CRP and WCC. Also increased sedimentation rate. Anaemia (decreased vitamin B12) Malabsorption (decreased albumin) Radiology Barium enema Biopsy

Question 48

Coeliac disease

Answer 48

Ingestion of gluten causes inflammatory response. Stopping gluten stops this.

Question 49

Immunology of coeliac disease

Answer 49

Prolamins are indigestable in the gut and therefore just sit there and cause a CD4+ T cell mediated inflammatory response.

Question 50

Symptoms of coeliacs

Answer 50

``` Fatigue and tiredness GI symptoms may be absent or mild Malabsorption Raised MCV Iron deficiency Possible IgA deficiency ```

Question 51

Who is most commonly affected by coeliacs

Answer 51

Middle aged females.

Question 52

Tests for coeliacs

Answer 52

Anti-tissue transglutiminase Endomysal test Small bowel biopsy Anaemia, follate deficiency,iron deficiency

Question 53

Treatment of coeliacs

Answer 53

Don't eat gluten | Vitamins

Question 54

Presentation of ischaemic bowel

Answer 54

``` ACUTELY UNWELL Presents as sudden onset abdominal pain Vomiting Abdominal distension Absent bowel sounds Tender stomach ```

Question 55

Ischaemic intestine

Answer 55

Surgical emergency | Gangrenous bowel needs removal

Question 56

Ischaemic colitis

Answer 56

May present with blood in poo, accompanied by diarrhoea

Question 57

Tests for ischaemic colitis

Answer 57

AXR- may show thumbprinting Most likely to occur in splenic flexure Flexible sigmoidoscopy- first line Biopsy reveals epithelial cell apoptosis

Question 58

Treatment of ischaemic colitis

Answer 58

Surgery | May only need symptomatic relief