Liver disease Flashcards
What organ can repair itself
Liver
What are some of the functions of the liver
Digestion (production of bile)
Storage (glycogen, copper, iron, vitamins A, B12, D, E, K)
Synthetic (coagulation factors, albumin, thrombopoietin, IGF-1)
Breakdown (drugs, alcohol, toxins, ammonia, bilirubin)
Immune (filtration of blood, Kupffer cells, “sieve”)
Metabolism (carbohydrate, protein, lipids)
What things does the liver synthesise
Coagulation factors
Albumin
Thrombopoietin
IGF-1
What is the blood supply to the liver
Hepatic artery (25%)
Hepatic portal vein (75%)
What is the main cell within the liver
Hepatocytes
What shape are liver cells
Hexagonal shaped
What is the portal triad
Arteriole (hepatic artery)
Venule (Hepatic portal vein)
Bile duct (flows into common bile duct)
What does the bile duct transport
Bilirubin
What is the pathology of liver disease
Result of damage to the hepatocytes which leads to loss of functions
What can cause acute liver failure
Paracetamol overdose
Viral hepatitis (A, B, E)
What things cause chronic liver failure
Alcohol
Viral hepatitis (B, C)
Non-alcoholic fatty liver disease (NAFLD)
Other (haemochromatosis, autoimmune, Wilson’s disease, cystic fibrosis…)
What is cachexia
wasting of body and muscles due to impaired metabolic function
What is Encephalopathy
Brain disfunction (caused by build up of ammonia with liver failure)
What are some symptoms and signs of liver disease
Cachexia – wasting of body and muscles due to impaired metabolic function
Encephalopathy (brain disturbance) – build up of ammonia
Jaundice – build up of bilirubin
Excoriations – scratches on skin due to itching
Coagulopathy (easy bleeding) – loss of TPO and coagulation factors
Bruising – due to easy bleeding
Ascites (fluid in abdomen) – reduced albumin production (decreased oncotic pressure of blood)
Peripheral oedema – fluid in legs due to reduced albumin production (decreased oncotic pressure)
Palmar erythema – red palms due to elevated oestrogen levels
Gynaecomastia – development of breast tissue in males
How is acute liver failure treated and managed
Critical care (patients very unwell)
Supportive measures and invasive monitoring
IV fluids, IV glucose, vitamin K, blood products
NAC (N-acetylcysteine) if paracetamol overdose
Liver transplant – early consideration
How is a paracetemol overdose treated
NAC (N-acetylcysteine)
IV fluids/glucose
liver transplant if severe
What is the max paracetemol dose
4000mg in 24 hrs (2 tablets every 4-6 hours)
Why does excess paracetemol cause liver failure
The breakdown product (NAPQI) causes hepatocyte necrosis
What is NAC
N-acytylcysteine
Why is NAC given to patients who have overdosed on paracetemol
Prevents hepatocyte necrosis
What are the symptoms of paracetemol overdose
First 24 hours: nausea and vomiting
2-3 days: right upper abdominal pain, recurrence of nausea and vomiting
3-4 days: signs of acute liver failure
What is end stage liver failure called
Cirrhosis
What is the manifestation of cirrhosis
Chronic inflammation and damage to liver cells
Damaged cells are replaced with scar tissue (fibrosis)
50% five-year survival rate
What is HCC
Hepatocellular carcinoma
liver cancer
Can the liver repair itself once cirrhosis is reached
No
What can cirrhosis of the liver cause within the rest of the body
The fibrosis in the liver means increased resistance to hepatic portal vein blood flow
This results in the back pressure of blood in the portal system - portal hypertension
Causes varices (swollen blood vessels) - often at the lower part of oesophagus
What are the stages of the liver from healthy to cirrhosis due to liver disease
Normal
Fatty liver
Steatohopatitis
Fibrosis
Cirrhosis
What are the liver stages from healthy to cirrhosis with excessive alcohol use
Normal
Alcoholic fatty liver
Alcoholic hepatitis
Cirrhosis
Why does hep b and c cause liver disease
They infect hepatocytes, resulting in damage and loss of function
What diseases cause liver failure
Hep B and C
Haemochromatosis (Fe overload in liver)
Autoimmune hepatitis (antibodies against hepatocytes)
Wilson’s disease (Cu overload in liver)
What are the dental implications of liver disease
Bleeding risk
-Reduced coagulation factor production
-Reduced thrombopoietin (TPO) = thrombocytopenia
-Increased spleen breakdown of platelets (portal hypertension)
Impaired drug metabolism
-Careful with advanced/end-stage liver disease
-Less plasma proteins for drug binging (more free drug in blood)
-BNF
-Paracetamol safe (but consider half dose)
-Avoid NSAIDs (antiplatelet action)
-Intravenous sedation – avoid in severe impairment
Alcohol (many implications)
-Consent
-Oral cancer risk
-NCTSL
-Interaction with metronidazole = “disulfiram-like reaction”
What tests can be carried out to assess liver disease
Full Blood Count (FBC)
-Platelet count <50 x 10*9 /L needs discussed with a senior doctor
-? Platelet infusion
Liver Function Test (LFT)
-Bilirubin, albumin and liver enzymes (ALT, AST, ALP)
-Gives a picture of acute inflammation in liver
-Normal does not always mean normal liver
Coagulation screen
-Gives information about intrinsic and extrinsic pathways of coagulation cascade
-Useful in assessing liver’s synthetic function
INR
-Information about liver’s synthetic function
What is the function of the biliary system
Production and delivery of bile and pancreatic enzymes
What is the function of the gallbladder
stores and concentrates bile, releases bile when fat is detected in small intestine
What is bile
fluid which emulsifies lipids to aid in the digestion and absorption of fat from diet
What is the composition of bile
Water (97%)
Bile pigments (conjugated bilirubin)
Bile salts
Cholesterol
Phospholipids
What causes jaundice
Blockage to flow of bile = build up of bilirubin in blood circulation resulting in jaundice
How is bilirubin formed
Breakdown of haem
How is bilirubin excreted
Exits body in faeces as stercobilin
Gives faeces brown colour
Small percentage exits body in urine as urobilin
Gives urine yellow colour
What is the definition of jaundice
yellowish discolouration of skin or sclera due to high levels of bilirubin in blood
What diseases cause jaundice
Pre-hepatic
Increased RBC breakdown
Haemolytic anaemia
Malaria
Intra-hepatic
Alcoholic hepatitis
Viral hepatitis
Cirrhosis
HCC
Post-hepatic
Gallstones
Pancreatic cancer
What are the types of jaundice
Prehepatic
Hepatic
Posthepatic
What are the risk factors for gallstones
Fair
Female
Forty
Fat
What are gallstones
Small stones that form in gallbladder and can block flow of bile
Form from concentrated bile salts
What are some potential consequences of gallstones
If block flow of bile = back pressure on flow
Pain (fatty foods = contraction of gallbladder)
Jaundice
Pancreatitis
How are gallstones treated
Ultrasound
CT scan
ERCP (Endoscopic Retrograde Cholangio-Pancreatography)
Treatment
Laparoscopic cholecystectomy
“lap chole”
Why is there a poor prognosis for pancreatic cancer
Late detection (deep in abdomen = asymptomatic)
Early metastatic spread
Can present as post-hepatic jaundice
Compression of common bile duct
How is pancreatic cancer treated
Palliative care (stent)
Chemotherapy
Surgery – Whipple’s procedure
What age range is primarily affected by pancreatic cancer
Majority are adenocarcinoma
80% of diagnosis 60 - 80-year-olds
