ACP-L21 & 22 HBP Pathology

The liver is located between the right 5th intercostal space and below the costal margin, at the mid-clavicular line.

The liver has 2 lobes, divided into 8 segments, and is covered by Glisson's capsule. It has a hexagonal structure.

The liver receives blood from both the portal vein (75%) and the hepatic artery (25%).

These are connections between the portal vein and the systemic circulation. There are 6 important ones.

Oesophageal varices are a consequence of portal hypertension, occurring in the lower oesophagus.

Liver biopsies are used to diagnose liver masses with inconclusive imaging, stage known liver disease, and plan treatment.

A percutaneous liver biopsy is done through the skin, but it carries risks like tumour seeding and bleeding.

Bilirubin, produced by the breakdown of red blood cells, is processed by the liver. It can then be excreted into bile or urine.

Signs of chronic liver disease include jaundice, pruritus, and ascites.

Portal hypertension causes varices in the oesophagus, and can lead to caput medusae and haemorrhoids.

Yellowing of the skin and eyes due to high bilirubin levels in the blood.

High levels of bilirubin in the blood.

Jaundice caused by increased bilirubin production.

Jaundice due to liver dysfunction.

Jaundice caused by blockage in bile ducts.

Bilirubin that hasn't been processed by the liver.

Bilirubin that has been processed by the liver.

Inherited condition causing mild jaundice.

High blood pressure in the portal vein, leading to complications like esophageal varices.

Brain dysfunction caused by liver failure.

Kidney malfunction caused by liver failure.

Fluid buildup in the abdomen caused by liver disease.

Enlarged spleen.

Vomiting blood.

Swollen veins in the esophagus.

Kernicterus is a serious neurological condition caused by high levels of bilirubin in the bloodstream. It can be fatal. The cause is a deficiency in the UDP-glucuronosyltransferase (UDP-GT) enzyme, which is responsible for processing bilirubin.

Portal hypertension refers to increased pressure within the portal vein system. It can arise from pre-hepatic (before liver), hepatic (within liver), or post-hepatic (after liver) causes.

Cirrhosis, a scarring of the liver, leads to portal hypertension due to increased vascular resistance and functional vasoconstriction.

Pre-hepatic portal hypertension is caused by problems in the portal vein before it reaches the liver. This could be due to thrombosis (blood clot), congenital stenosis (narrowing), or compression from a mass.

Post-hepatic portal hypertension is caused by problems after the blood leaves the liver, such as heart failure, venous thrombosis, or the Budd-Chiari syndrome.

Cirrhosis is a chronic liver disease where healthy liver tissue is replaced by scar tissue, causing the liver to harden and lose its ability to function properly.

Cirrhosis can lead to portal hypertension, ascites, jaundice, and other complications which can be life-threatening.

Cirrhosis is classified into two main types: macro-nodular (e.g., viral hepatitis) and micro-nodular (e.g., alcoholic fatty liver disease).

A TIPS procedure is done to relieve portal hypertension by creating a new channel connecting the portal vein to the hepatic vein, bypassing the damaged liver.

A TIPS procedure is usually done when there's significant portal hypertension, often due to cirrhosis, and to prevent complications like variceal bleeding.

Resorption of internal bleeding leads to hemoglobin degradation, which in turn releases proteins that can contribute to variceal bleeding.

Complications of variceal bleeding can include anemia due to blood loss, infection, and liver failure.

Pre-renal failure is a condition where the kidneys are not getting enough blood flow, leading to a decreased ability to filter waste.

Non-alcoholic fatty liver disease (NAFLD) is a common condition where fat builds up in the liver, not caused by excessive alcohol consumption.

NAFLD is linked to metabolic syndrome, which includes central obesity, hypertension, hyperglycemia, hypertriglyceridemia, and low HDL-C.

NAFLD is very common, with a prevalence of 27% in Hong Kong. It is the most frequent cause of chronic hepatitis in HK

Estrogen has a protective effect against NAFLD, especially in pre-menopausal women.

Both NAFLD and Alcoholic Liver Disease (ALD) share similar pathological features, often indistinguishable.

In macrovesicular steatosis, fat accumulates within liver cells, displacing the nucleus.

NAFLD can be asymptomatic or cause hepatomegaly and mildly deranged liver function tests.

There is no specific cure for NAFLD, but lifestyle modifications like weight loss, exercise, and a healthy diet are crucial.

A chronic autoimmune disease characterized by the destruction of small bile ducts in the liver, causing inflammation and scarring. This often leads to liver failure.

An autoimmune disease that causes inflammation and scarring of the bile ducts, both inside and outside the liver. It can lead to cholestasis (bile buildup) and liver failure.

PBC mainly affects intrahepatic bile ducts (within the liver), while PSC involves both intrahepatic and extrahepatic bile ducts (outside the liver). PBC is more common in women, while PSC is more common in men. PBC is associated with anti-mitochondrial antibodies, while PSC is associated with anti-neutrophil cytoplasmic antibodies.

This describes the characteristic appearance of the bile ducts in a cholangiogram (imaging test) of someone with PSC. The bile ducts are narrowed and appear like beads strung together.

This appearance on a cholangiogram is highly suggestive of PSC, helping in its diagnosis. It indicates the specific pattern of bile duct scarring and narrowing characteristic of the disease.

PBC often occurs alongside Sjogren's syndrome, a condition that causes dryness of the eyes and mouth.

PSC is often linked to inflammatory bowel diseases such as ulcerative colitis and Crohn's disease.

Cholangiograms are imaging tests that visualize the bile ducts. They can be performed endoscopically (ERCP) or using magnetic resonance imaging (MRCP). They help diagnose PSC and other biliary diseases.

An elevated ALP level in the blood is often a sign of liver disease, particularly PBC and PSC. It indicates that the bile ducts are not functioning properly, leading to an accumulation of bile.

Common symptoms include fatigue, jaundice (yellowing of skin), itching, abdominal pain, and dark urine. However, many patients are asymptomatic in the early stages.