Liver Function Tests and Related Conditions

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Questions and Answers

Besides liver damage or disease, what other conditions might higher-than-usual levels of ALP indicate?

Certain bone diseases.

What are the two proteins specified for liver function tests, and what do lower-than-usual levels of these indicate?

Albumin and total protein. Lower levels may indicate liver damage or disease.

What is the approximate plasma bilirubin level in µmol/L at which jaundice is typically detectable clinically?

40 µmol/L

What is bilirubin, and what does an elevated level in blood suggest about the patient's health?

Bilirubin is a substance produced during the breakdown of red blood cells. Higher levels might mean liver damage or disease. Signup and view all the answers

Name the two primary causes of pre-hepatic jaundice.

Hemolysis and congenital hyperbilirubinemia Signup and view all the answers

What is GGT and what does a higher-than-usual level potentially indicate about a patient's health?

GGT is an enzyme in the blood. Higher-than-usual levels may mean liver or bile duct damage. Signup and view all the answers

What is the key characteristic of cirrhosis in terms of hepatic tissue?

Diffuse hepatic fibrosis and nodule formation Signup and view all the answers

If a patient has an increased Prothrombin time (PT), what are two possible reasons for the increase?

Liver damage or treatment with blood-thinning drugs like warfarin. Signup and view all the answers

What is the typical hepatic venous pressure gradient in a healthy individual in mm Hg?

5-6 mm Hg Signup and view all the answers

At what hepatic venous pressure gradient in mm Hg does the risk of variceal bleeding increase?

12 mm Hg Signup and view all the answers

What is the primary characteristic of autoimmune hepatitis in terms of serum proteins?

Elevated levels of IgG Signup and view all the answers

When palpating the liver using the standard technique, where should your left hand be placed on the patient's body?

Under the patient, parallel to and supporting the right 11th and 12th ribs. Signup and view all the answers

Besides cirrhosis, list another potential underlying disease that often leads to portal hypertension.

Viral Hepatitis Signup and view all the answers

What is the 'hooking technique' used for when examining the liver?

It is an alternative method for palpating the liver, using both hands to feel the liver edge. Signup and view all the answers

What are the two main mechanisms by which cholestatic jaundice can occur?

Failure of hepatocytes to initiate bile flow and obstruction of bile ducts. Signup and view all the answers

What clinical sign would suggest that an individual's liver is enlarged?

The liver edge extends more than 1.2 inches (3 cm) below the right costal margin. Signup and view all the answers

What is the purpose of asking a patient to take a deep breath when palpating for Murphy's sign?

To bring the inflamed gallbladder into contact with the examiner's hand. Signup and view all the answers

What are some non-specific symptoms that may present with acute liver injury?

Fatigue and abnormal Liver Function Tests (LFTs). Signup and view all the answers

What is the main characteristic that defines chronic liver injury?

Hepatic injury, inflammation and/or fibrosis occurring in the liver for more than 6 months. Signup and view all the answers

Besides jaundice, what other signs might be present in severe liver damage due to chronic liver injury?

Portal hypertension, cirrhosis, and hepatic decompensation. Signup and view all the answers

What is a common finding in patients with chronic liver injury during early stages?

Patients can be asymptomatic with fluctuating abnormal Liver Function Tests (LFTs). Signup and view all the answers

What is the primary cause of acute cholecystitis?

Obstruction of the gallbladder neck or cystic duct by a gallstone. Signup and view all the answers

List three common locations where pain may be felt during an acute cholecystitis attack?

Right upper quadrant, epigastrium, right shoulder tip. Signup and view all the answers

What is the recommended treatment for chronic cholecystitis?

Elective laparoscopic cholecystectomy Signup and view all the answers

What percentage of patients with gallstones develop stones in the common bile duct?

10–15%. Signup and view all the answers

Besides pain and jaundice, name 2 other symptoms associated with choledocholithiasis.

Fever, pruritus. Signup and view all the answers

What is the purpose of Liver Function Tests?

To screen for liver infections, monitor liver disease, look for cirrhosis and monitor side effect of medication. Signup and view all the answers

Name two enzymes that are tested in liver function tests and what they indicate?

Alanine transaminase (ALT), and Aspartate transaminase (AST), which when elevated indicate liver damage or disease Signup and view all the answers

Where is alkaline phosphatase found and what its function?

It is found in the liver and bone and is important for breaking down proteins. Signup and view all the answers

Study Notes

Liver Disorders

The liver is a vital organ with many functions, including nutrient metabolism, protein synthesis, storage, and excretion.

Important Liver Functions

Nutrient Metabolism: The liver processes carbohydrates, proteins, and lipids.
Protein Synthesis: The liver produces albumin, coagulation factors, complement factors, and other proteins.
Storage: The liver stores iron, copper, and vitamins A, D, and B12.
Immune Functions: Kupffer cells in the liver perform immune functions.
Excretion: The liver excretes bile salts, bilirubin, drugs, phospholipids, and cholesterol.

Palpation of the Liver

Palpating the liver involves placing one hand under the patient and the other hand alongside the ribs.
Press gently in and up as the patient takes a deep breath.
The liver border can be identified through percussion (listening for the change from dull to resonant sound).
Another technique is "hooking," where fingers are placed below the liver border, and the patient inhales.
The edge of the descending liver can be felt.

Palpation of the Gallbladder

The liver position is important for gallbladder palpation.
The hand placement is positioned to palpate the liver and potentially the gallbladder below it.
The gallbladder moves inferiorly with inspiration.

Murphy's Sign

Murphy's sign is used to diagnose acute cholecystitis (inflammation of the gallbladder).
The patient is asked to take a deep breath while palpating the right subcostal area.
Pain during inspiration when the gallbladder touches the examiner's hand confirms a positive Murphy's sign.

Liver Assessment (General)

Face: Jaundice, spider naevi, parotid swelling, xanthelasma.
Chest: Loss of body hair, gynecomastia.
Abdomen: Scars, distension, venous patterns, testicular atrophy.
Hands: Clubbing, Dupuytren's contracture, leuconychia.
Legs: Bruising, edema.
Other Observations: Smell, weight loss, scratch marks (itching).
Aspiration of ascitic fluid: Useful for diagnosing abdominal accumulation of fluid.

Acute Liver Injury

Non-specific symptoms like fatigue, abnormal liver function tests (LFTs), or jaundice could indicate acute liver injury.
Acute liver failure could be a possible outcome of non-specific acute liver injury.

Chronic Liver Injury

Chronic liver injury has prolonged inflammations, and/or fibrosis for more than 6 months.
Early stages might be asymptomatic and have fluctuating abnormal LFTs.
Advanced stages may present with jaundice, portal hypertension, or cirrhosis indicators.

Causes of Acute Liver Failure

Cryptogenic (unknown): 5-10% cases
Viral infection (Hepatitis A, B, or E, though rare): ~5% cases
Drugs: ~70-80% cases (including paracetamol)
Poisons (Amanita phalloides): ~<5% cases
Other miscellaneous factors

Classification of Acute Liver Failure

This is determined by the timescale of jaundice to cerebral oedema (a clinical presentation of encephalopathy): hyperacute (<7days), acute (8-28 days), and subacute (>29 days to 12 weeks).

Complications of Acute Liver Failure

Encephalopathy and cerebral oedema
Hypoglycaemia
Metabolic acidosis
Infection (bacterial, fungal)
Renal failure
Multi-organ failure (hypotension and respiratory failure)

Clinical Assessment of Hepatic Encephalopathy

Clinical grades (1-4) are determined by the severity of mental changes, from slight confusion to unconsciousness.

Investigations for Acute Liver Failure

Toxicology screen of blood and urine
Screening for blood-borne viral infections (HBsAg, IgM anti-HBc, IgM anti-HAV)
Testing for other viruses
Serum copper, urinary copper, slit-lamp examination
Autoantibodies (e.g., ANA, ASMA, LKM, and SLA)
Immunoglobulins
Ultrasound of liver and hepatic veins

Chronic Liver Failure

Symptoms include worsening synthetic liver function, prolonged prothrombin time, low albumin levels, jaundice, and portal hypertension.
Common complications include variceal bleeding, hepatic encephalopathy, ascites, spontaneous bacterial peritonitis, and hepatorenal failure.

Jaundice

Clinically detectable when plasma bilirubin exceeds 40 μmol/L (~2.5 mg/dL).
Pre-hepatic: haemolysis and congenital hyperbilirubinaemia.
Hepatocellular: liver's inability to transport bilirubin into the bile.
Obstructive (cholestatic): failure of the liver to initiate bile flow, or obstruction of the bile ducts.

Hepatomegaly

An enlarged liver, possibly caused by metastasis, cysts, cirrhosis, hepatic vein outflow obstruction, or infiltration.

Ascites

Fluid accumulation in the abdomen.
Exudative: High protein, often due to cancer or tuberculosis.
Transudative: Low protein, usually caused by cirrhosis or other factors affecting blood pressure or protein production.
Associated clinical findings can vary depending on the cause.

Causes of Ascites

Underlying medical conditions (e.g., malignant diseases, hepatic failure)
Other causes: Hypoproteinaemia, nephrotic syndrome, and protein-losing enteropathy

Cirrhosis

Chronic and diffuse hepatic fibrosis, and nodule formation.
An important cause of premature death.
Common causes include alcohol use, chronic viral hepatitis (e.g., B and C), non-alcoholic fatty liver disease, autoimmune diseases, and genetics like haemochromatosis.

Causes of Cirrhosis

Alcohol-related
Chronic viral hepatitis
Non-alcoholic fatty liver disease
Immune disorders
Biliary conditions (primary biliary cirrhosis)
Genetic disorders (e.g., haemochromatosis, Wilson's disease)
Others (e.g., cystic fibrosis)

Clinical Features of Hepatic Cirrhosis

Possible hepatomegaly (though sometimes small liver).
Jaundice
Ascites
Various circulatory, endocrine, and other changes.

Prognosis

Patients may have advanced disease and serious complication with a high mortality.
25% of patients usually survive 5 years from diagnosis.
Prognosis is good when the underlying cause is corrected (e.g., alcohol use, hemochromatosis, or Wilson's disease).

Portal Hypertension (PH)

Complication often associated with cirrhosis, but has other causes.
Normal hepatic venous pressure gradient is 5-6mm Hg.
Clinically significant portal hypertension occurs when the gradient exceeds 10mm Hg, and risk of variceal bleeding increases beyond 12mm Hg.

Classification of PH

Pre-hepatic, pre-sinusoidal
Intrahepatic pre-sinusoidal
Intrahepatic post-sinusoidal
Post-hepatic, post-sinusoidal

Complications of Portal Hypertension

Variceal haemorrhage (oesophageal, gastric, other)
Congestive gastropathy
Hypersplenism
Ascites
Iron deficiency anaemia
Renal failure
Hepatic encephalopathy

Viral Hepatitis

Common causes include hepatitis A, B, C, D, and E.
Other less common or rare causes such as CMV, Herpes simplex, yellow fever.

Viral Hepatitis - Features of Different Viruses

Details of different viruses, including group, nucleic acid, size, incubation, spread, presence or absence of chronic infection/prevention measures.

Complications of Acute Viral Hepatitis

Acute liver failure, cholestatic hepatitis, aplastic anaemia, chronic liver disease, and cirrhosis
Relapsing hepatitis

Autoimmune Hepatitis

Immune-mediated liver injury
Characterized by antibodies and T lymphocytes reactive to self-proteins.
Often associated with other autoimmune conditions and elevated IgG levels.

Conditions Associated with Autoimmune Hepatitis

Migrating polyarthritis, urticarial rashes, lymphadenopathy, Hashimoto's thyroiditis, thyrotoxicosis, myxoedema, pleurisy
Coombs positive haemolytic anaemia, transient pulmonary infiltrates, ulcerative colitis, glomerulonephritis, and nephrotic syndrome

Clinical Features of Autoimmune Hepatitis

Includes fatigue, anorexia, jaundice, fever, arthralgia, vitiligo, and epistaxis.

Acute Cholecystitis

Inflammation of the gallbladder, typically due to gallstone obstruction of the cystic duct.
Clinical features involve pain in the right upper quadrant and epigastrium, right shoulder, or interscapular region, fever, and less commonly, jaundice.

Choledocholithiasis

Gallstones in the common bile duct.
May be asymptomatic or manifest as abdominal pain, fever, pruritus, and/or dark urine. Jaundice is common, often pain-associated.