Diseases of the liver and pancreas Flashcards Preview

Clinical Pathology > Diseases of the liver and pancreas > Flashcards

Flashcards in Diseases of the liver and pancreas Deck (49):
1

Which organelle conjugates bilirubin?

Smooth endoplasmic reticulum

2

What are the functions of the liver?

Carbohydrates
- Glycogen storage & synthesis
- Glycolysis & gluconeogenesis

Proteins
- Synthesis & catabolism
- Clotting factors
- Amino acid metabolism &urea synthesis

Lipids
- Lipoprotein & cholesterol synthesis
- Fatty acid metabolism
- Bile acid synthesis

Excretion & detoxification
- Bile acid & bilirubin excretion
- Drug detoxification & excretion
- Steroid hormone inactivation & excretion

Miscellaneous
- Iron storage
- Vitamin A, D, E & B12 storage & metabolism

3

What is measured by LFTs?

Alkaline phosphatase

ALT (alanine aminotransferase)

AST (aspartate transaminase)

Bilirubin

Albumin

Total protein

GGT (glutamyl transferase)

4

What tests might be used for specific liver functions?

Carbohydrate metabolism
- glucose

Protein metabolism
- albumin
- urea
- prothrombin (clotting factors)

Lipid metabolism
- cholesterol
- triglycerides
- bile acids

Excretion and detoxification
- bilirubin
- drugs
- steroid hormones

Misc
- Ferritin (iron storage)
- Prothrombin time (Vit K)

5

What tests give an indication of hepatocyte damage?

Aminotransferases
- Alanine/ALT
- Aspartate/AST
- Found in the cell and only released by cellular damage.

ALT is more specific for liver than AST

AST also found in muscle and red blood cells

Tumour markers – α-fetoprotein (primary hepatocellular carcinoma)

6

What tests give an indication of biliary tract damage?

Impaired excretory function
- Increased Conjugated bilirubin

Increased synthesis of enzymes by cells lining the bile canaliculi
- ALP
- γGT

7

What might be the causes of increased ALP in biliary tract damage?

Cholestasis (intra- or extrahepatic)

Infiltrative diseases

Space-occupying lesions (tumours)

Cirrhosis

8

Which organs also secrete ALP isoenzymes?

Liver

Bone

Intestine

Placenta

9

If γGT and ALP are raised, what might this mean?

A raised γGT supports a liver source of ALP (as opposed to any other isoenzyme).

Elevated due to structural damage

10

What can cause biliary tract damage?

alcohol

enzyme inducing agents
- e.g. anti-epileptics

fatty liver
- e.g. due to alcohol, diabetes or obesity

heart failure

prostatic disease

pancreatic disease
- acute & chronic pancreatitis, cancer

kidney damage
- ARF, nephrotic syndrome, rejection

11

What are the biochemical markers of fibrosis?

ELF score
- PIIINP
- TIMP-1
- Hyaluronic acid

12

What is bilibrubin a measure of?

Excretory capacity of the liver and free flow of bile.

13

What is bilirubin measured as?

Total

Unconjugated
- Pre-hepatic & Hepatic

Conjugated
- Post-hepatic (Obstructive) & Hepatic

14

What serum level of bilirubin is considered to be jaundice?

> 40-50 μmol/L

15

What happens to bilirubin in the liver?

It is conjugated to bilirubin glucuronide by glucuronyl transferase.

16

What protein is bilirubin bound to in the blood?

Albumin

17

What are the pre-hepatic causes of jaundice?

Haemolysis
- e.g. Rhesus incompatibility

Ineffective erythropoiesis
- e.g. spherocytosis

18

What are the post-hepatic (obstructive) causes of jaundice?

Gallstones

Biliary Stricture

Cancer
- i.e. cholangiocarcinoma, head of pancreas

Cholangitis

19

What are the hepatic causes of jaundice?

Unconjugated
- Pre-microsomal
- Microsomal
- Inherited disorders of conjugation e.g. Gilberts, Crigler-Najjar

Conjugated
- Post-microsomal/impaired excretion
- Intrahepatic obstruction
- Inherited disorders of excretion e.g. Dubin-Johnson, Rotor.

20

What are the inborn errors of bilirubin metabolism?

Decreased activity of UDP glucuronyl transferase
- Gilbert’s
- Crigler-Najjar

Reduced ability to excrete bilirubin glucuronide
- Dubin-Johnson
- ROTOR

21

What is the pathway from haemoglobin to bilirubin glucuronide?

Haemoglobin -> bilirubin albumin-bound bilirubin -> bilirubin -> bilirubin glucuronide -> bile duct

22

The patient is jaundiced, their AST/ALT is elevated and their ALP is normal. What will are they likely to have?

Approx 90% of these patients will have hepatitis

23

The patient is jaundiced, their AST/ALT is normal and their ALP is elevated. What will are they likely to have?

Approx 90% will have obstructive jaundice

24

What will urine tests show in prehepatic jaundice?

Unconjugated bilirubin - no urinary bilirubin

25

What will urine tests show in hepatic jaundice?

Variable depending on degree of obstruction due to either disease or inflammatory oedema

26

What will urine tests show in post-hepatic jaundice?

Dark urine (&pale stools)

27

What are the systemic effects of liver disease?

jaundice

oestrogen XS
- gynaecomastia
- spider naevi
- liver palms
- testicular atrophy

bruising

pigmentation

clubbing

dependent oedema

ascites

encephalopathy

osteomalacia / osteoporosis

28

What specific tests can be used in chronic active and autoimmune hepatitis?

Anti smooth muscle, anti liver/kidney, anti microsomal and anti nuclear antibodies

29

What test can be used for primary biliary cirrhosis?

Anti mitochondrial antibodies

30

What test can be used for hereditary haemachromatosis?

Ferritin

transferrin saturation

liver biopsy

genetic testing

31

What tests can be used to detect Wilson's disease?

Caeruloplasmin

urine copper

plasma copper

liver biopsy

32

Are routine LFTs useful?

No - only 1% of people with abnormal LFTs have liver disease

33

What should LFTs be measured?

Signs and symptoms ?
- Pain
- itchy
- jaundice
- TATT
- bruising

Lifestyle ?
- Alcohol
- obesity
- diabetes
- recent travel
- drug use

Is liver disease present ?
- hepatitis
- haemochromatosis
- liver cancer,
- drugs

What is the severity ?
- chronic hepatitis vs acute onset

34

How does the pancreas drain?

Drains via main pancreatic duct joined to the common bile duct.

Opens into duodenum via Sphincter of Oddi.

35

What part of the pancreas produces endocrine secretions?

Islets of Langerhans

36

What are the endocrine secretions of the pancreas?

Insulin

Glucagon

Pancreatic Polypeptide

37

What part of the pancreas produces exocrine secretions?

Ductal and acinar cells

38

What are the exocrine secretions of the pancreas?

Bicarbonate

Digestive enzymes
- Trypsin, Chymotrypsin & Elastase
- Carboxypeptidases
- Amylase
- Lipase

39

What is acute pancreatitis?

Acute necrotising liquefaction

Inflammatory

40

What is the aetiology of acute pancreatitis?

Gallstones

Alcohol

Drugs

Hypertiglyceridaemia

Trauma, infectious

Rare tumours, autoimmune, Scorpion Toxins!

41

What are the symptoms of acute pancreatitis?

Severe epigastric pain

Sudden onset

Radiating to the back

42

What are the potential biochemical features of acute pancreatitis?

Uraemia

Hypoalbuminaemia

Hypocalcaemia

Hyperglycaemia

Metabolic acidosis

Abnormal LFTs

43

What tests might be used in the diagnosis of acute pancreatitis?

Amylase or Lipase

Imaging

Clinical History

44

What is chronic pancreatitis?

Progressive loss of both islet cells and acinar tissue.

45

What is the presentation of chronic pancreatitis?

Abdominal pain

Malabsorption
- often presenting feature

Impaired glucose tolerance

Alcohol often an important factor

46

Are tests of exocrine function of any use in chronic pancreatitis?

No - only in acute exacerbations

47

How does one perform the diagnosis and management of chronic pancreatitis?

Imaging

Pancreatic Function test for investigating insufficiency
- Direct
- Indirect

Miscellaneous
- Vitamin D
- calcium
- FBC
- LFTs
- glucose
- lipids

48

What are direct (invasive) tests of pancreatic function?

Intubation to collect aspirates in the duodenum.

Secretin, CCK, Lundh Tests

49

What are indirect (non-invasive) tests of pancreatic function?

Pancreatic enzyme analysis in stools (Elastase)

Trypsinogen (IRT) measured in blood in CF screening

Pancreolauryl & NBT-PABA tests

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