Liver Disease

Question 1

what are the 4 causes of viral hepatitis

Answer 1

hep a - most common but least serious
hep b more acute illness may be chronic
hep c often asymptomatic and chronic
hep e commonest in the uk resolves in most patients

Question 2

how does viral hepatitis lead to liver damage

Answer 2

chronic infection and inflammation leads to fibrosis and cirrhosis

Question 3

what causes alcoholic liver disease

Answer 3

causes inflammation and fatty acid accumulation - these can cause fibrosis and cirrhosis

Question 4

what is NAFLD and what is it associated with

Answer 4

non-alcoholic fatty liver disease - associated with type 2 diabetes and obesity
leads to fat accumulation and inflammation (NASH)

Question 5

what’s the difference between hepatitis and cirrhosis

Answer 5

hepatitis is reversible but cirrhosis is irreversible scar tissue damage to the liver

Question 6

how is alcohol degraded in the liver

Answer 6

alcohol dehydrogenase and eventually to acetate

Question 7

describe the breakdown of harm metabolism

Answer 7

check diagrams

Question 8

how can you tell if someone has bad liver damage

Answer 8

insufficient hepatocytes for synthesis of albumin ad conjugation/excretion of bilirubin (high bili and low albumin)

Question 9

what are the symptoms of liver disease

Answer 9

jaundice - deposition of bilirubin
ascites - fluid retention in abdomen
oesophageal varices - caused by portal hypertension

Question 10

what metabolic processes maintain blood glucose when fasting

Answer 10

glycogenolysis - breakdown of liver glycogen to glucose

gluconeogenesis - synthesis of new glucose from amino acids, lactate, pyruvate and glycerol

Question 11

blood glucose production is reduced in alcohol addicts because

Answer 11

liver is damaged, fewer hepatocytes available to store glycogen or perform gluconeogenesis

Question 12

what effect will metabolism of alcohol have on gluconeogenesis

Answer 12

breakdown of ethanol = lots of NADH
inhibits entry of pyruvate and lactate into gluconeogenesis so process is inhibited by alcohol breakdown

why drinking makes you hungry

Question 13

why is thiamine deficiency common in heavy drinkers

Answer 13

poor diet

damage to GI tract due to alcohol reduces absorption

Question 14

why is thiamine needed to metabolise glucose

Answer 14

cofactor for pyruvate dehydrogenase - catalyses link reaction for entry of pyruvate into krebs

Question 15

why is drinking alcohol with the drugs such as antihistamines, antidepressants, antibiotics and NSAIDS

Answer 15

competition between booze and drugs for cytochrome P450 - causes slower clearance of both

increased risk of alcohol effect and side effects from drugs

Question 16

why is prescribing drugs to alcoholics dangerous

Answer 16

chronic alcohol usage induces synthesis of cytochrome P450 enzymes leading to increased metabolism of prescribed drugs
therefore need an increased dosage of drug

Question 17

how do these drugs help with alcohol dependance 
diazepam 
disulphiram 
nalterxone 
acamprosate

Answer 17

Cross tolerance with alcohol, so helps reduce delirium tremens (withdrawal symptoms). The dose can gradually be reduced

Inhibits aldehyde dehydrogenase – makes the person feel ill if they drink

Opioid reuptake inhibitor – reduces craving for alcohol

Binds N-methyl-D-aspartate (NMDA) receptors in the brain, suppressing the craving for alcohol

Question 18

what are the clinical effects of biliary obstruction

Answer 18

jaundice 
dark urine 
pale stools 
ithcing 
pain 
steatorrhoea 
weight loss 
vitamin deficiencies 
disturbed lipid metabolism