LFT Interpretation Quiz: Practice Liver Function Tests

What percentage of adults are thought to have Non-alcoholic fatty liver disease (NAFLD)?

What is the main cause of fat deposition in the liver cells in NAFLD?

What is the most common association of NAFLD?

What is the final stage of NAFLD, characterized by permanent scarring of the liver?

What is the name of the disease characterized by a deficiency of alpha-1 antitrypsin (A1AT)?

What is the term for the measurement of the amount of iron bound to transferrin in the blood?

What is the typical liver panel composed of?

What is indicated by an ALT > AST ratio?

What is suggested by an AST > ALT ratio in a 2:1 ratio?

What does an isolated rise in GGT indicate?

What does a dark urine and normal stools indicate in terms of bilirubin levels?

What is the next step in investigating abnormal LFTs without a clear cause?

Immunoglobulins and Liver Diseases

Immunoglobulins can be affected by Wilson's disease and A1AT levels, which can impact liver function

Non-Alcoholic Fatty Liver Disease (NAFLD)

30% of adults are thought to have NAFLD, making it the most common cause of abnormal LFTs in the UK
Mainly affects those with metabolic syndrome
Risk factors: obesity, poor diet, low activity levels, T2DM, high cholesterol, middle age onwards, smoking, HTN
Cause: fat deposition in liver cells, potentially due to decreased sensitivity of insulin receptors
Stages: steatosis (fatty liver), non-alcoholic steatohepatitis (steatosis + inflammation), fibrosis (production and deposition of fibrotic tissue), cirrhosis (chronic fibrosis causing permanent scarring)

Clinical Features of NAFLD

Generally asymptomatic, but may cause non-specific symptoms: fatigue, general malaise, abdominal discomfort

Liver Function Tests (LFTs)

Typical liver panel: total protein, albumin, ALP, ALT, bilirubin (+ AST + GGT)
ALT and AST: rise in conjunction with hepatocellular injury
ALT > AST: normal hepatocellular picture
AST > ALT in 2:1 ratio: alcoholic liver disease
ALP: increased in liver pathologies due to bile salt accumulation
GGT: isolate rise = chronic alcohol excess; non-specific and also elevated in COPD, renal failure, post MI + hepatic malignancies
Bilirubin: isolated rise = pre-hepatic jaundice; dark urine + normal stools = pre-hepatic jaundice; dark urine + pale stools = post-hepatic jaundice
Investigating abnormal LFTs: perform non-invasive liver screen, including USS liver, Hepatitis B and C serology, Autoantibodies

Test your knowledge of liver function tests, including the typical liver panel, and how to interpret ALT, AST, and ALP levels in relation to hepatocellular injury and liver disease. Learn how to identify different liver pathologies, such as chronic and acute injury, and alcoholic liver disease.