Liver Flashcards
What is chronic liver failure?
Loss of the liver’s ability to regenerate or repair.
What are the types of chronic liver failure?
- Fulminant hepatic failure: within 8 weeks of onset of underlying illness
- Late-onset hepatic failure: 8-26 weeks since onset
- Chronic decompensated hepatic failure: latent period >6months.
What are the causes of chronic liver failure?
Toxins: • Alcohol • Paracetamol poisoning (most common acute cause) Infections: • Viral hepatitis • EBV • CMV. Neoplastic: • Hepatocellular carcinoma. Metabolic: • Wilson’s • A1At deficiency • Haemochromatosis. Others: • Acute fatty liver of pregnancy • Ischaemia • Autoimmune liver disease.
What is the pathophysiology of chronic liver disease?
Generally destruction of the hepatocytes, the development of fibrosis in response to chronic inflammation. The destruction of the architecture of the nodules of the liver removes the ability of the liver to adequately perform functions, repair and regenerate.
What are the symptoms of chronic liver disease?
- Jaundice
- Ascites
- Variceal haemorrhage secondary to portal hypertension
- Hepatic encephalopathy
- Mental state shows drowsiness and confusion due to cerebral oedema.
What do the investigations in chronic liver disease show?
- Raised bilirubin
* Glucose low as no glucogenesis.
How do you treat chronic liver failure?
- Treat symptoms e.g. mannitol for hepatic encephalopathy
* Liver transplant.
What are the complications of chronic kidney failure?
Infection and haemorrhage.
What is cirrhosis?
Not a specific disease. Is an end stage of all progressive chronic liver diseases, which once fully developed is irreversible and may be associated clinically with symptoms and signs of portal hypertension and liver failure. Characterised by loss of normal hepatic architecture, nodular regeneration and bridging fibrosis.
What are the causes of cirrhosis?
Common: • Chronic alcohol abuse • Non-alcoholic fatty liver disease • Hepatitis B±D • Hepatitis C.
Others:
• Primary biliary cirrhosis
• Autoimmune hepatitis (presents as high ALT)
• Hereditary haemochromatosis (iron overload)
• Wilson’s disease
• Alpha-Antitrypsin deficiency
• Drugs e.g. amiodarone and methotrexate.
What is the pathophysiology of cirrhosis?
- Chronic liver injury results in inflammation, matrix deposition, necrosis and angiogenesis which all cause fibrosis.
- Liver injury causes necrosis and apoptosis, releasing cell contents and reactive oxygen species (ROS)
- This activates hepatic stellate cells and tissue macrophages (Kupffer cells)
- Stellate cells release cytokines that attract neutrophils and macrophages to the liver and so there is further inflammation and necrosis which causes fibrosis
- Results in severe reduction in liver function as fibrosis in non-functioning.
What are the two types of cirrhosis?
- Micronodular cirrhosis: regenerating nodules usually <3mm in size with uniform involvement of the liver. Often caused by alcohol or biliary tract disease
- Macronodular cirrhosis: nodules of varying size and normal acini (functioning unit of liver) may be seen within larger nodules. Often caused by chronic viral hepatitis.
What is decompensated cirrhosis?
When the liver is damaged to the point that it cannot function adequately and overt clinical complications (such as jaundice, ascites, variceal haemorrhage and hepatic encephalopathy) are present. Events causing decompensation include infection, portal vein thrombosis and surgery.
What are the symptoms of compensated cirrhosis?
- Asymptomatic
* Non-specific e.g. weight loss, weakness, fatigue.
What are the symptoms of decompensated cirrhosis?
- Jaundice
- Pruritis
- Abdominal pain due to ascites.
What are the signs of cirrhosis?
- Bruising
- Leukonychia: white discolouration on nails due to hypoalbuminaemia
- Clubbing of the fingers
- Palmar erythema
- Spider naevi
- Dupuytren’s contracture
- Xanthelasma: yellow fat deposits under skin usually around eyelids
- Ascites
- Jaundice
- Oedema due to decreased albumin in blood.
What are the best indicators for liver function?
Serum albumin and prothrombin.
Low albumin and long prothrombin means malfunction.
What are the investigations in cirrhosis?
- Liver biopsy
- LFTs: serum albumin and prothrombin time best indicators of liver function (raised bilirubin, aspartate amino transferase (AST) and alanine aminotransferase (ALT). Low albumin and long prothrombin means malfunction)
- Liver biochemistry
- FBC: low platelets (due to loss of thrombopoteitin)
- Transient elastography
- Abdominal ultrasound
- Abdominal CT
- Abdominal MRI
- Upper GI endoscopy for possible oesophageal varices.
What is the treatment for cirrhosis?
Treat underlying cause: • Alcohol abstinence • Antivirals for hepatitis C • Spironolactone for ascites. Liver transplant. Good nutrition. 6 month ultrasound screening for hepatocellular carcinoma.
What are the complications of cirrhosis?
- Coagulopathy: fall in clotting factors II, VII, IX and X
- Encephalopathy: liver flap (flapping tremor with wrist extended) and confusion/coma. This is when toxins e.g. ammonia make it into the brain and cause mental deficits
- Thrombocytopenia
- Hepatocellular carcinoma
- Hypoalbuminaemia
- Portal hypertension: ascites, oesophageal varices.
What are the causes of portal hypertension?
Pre-hepatic: due to blockage of portal vein before liver
• Portal vein thrombosis.
Intra-hepatic: resulting from distortion of liver architecture
• Cirrhosis (most common cause)
• Schistosomiasis
• Sarcoidosis
• Congenital hepatic fibrosis.
Post-hepatic: due to venous blockage outside of the liver
• Right HF
• Constrictive pericarditis
• IVC obstruction.
What is the pathophysiology of portal hypertension?
Following liver injury and fibrogenesis (e.g. due to cirrhosis), the contraction of activated myofibroblasts (mediated by endothelin, nitric oxide and prostaglandins) contributes to increased resistance to blood flow.
This leads to portal hypertension which causes splanchnic vasodilation and so a drop in BP. This means increased CO to compensate for BP and salt and water retention to increase blood volume which causes hyperdynamic circulation (increased portal flow). This leads to formation of collaterals between portal and systemic systems e.g. lower oesophagus and gastric cardia.
What are the signs of portal hypertension?
- Ascites
- Hepatic encephalopathy
- Splenomegaly
- Oesophago-gastric varices.
What is a varice?
A dilated vein at risk of rupture resulting in haemorrhage and can cause GI bleeding in the GI system.
When are varies likely?
- Around 90% of patients with cirrhosis develop gastro-oesophageal varices over 10 years but only a third will bleed
- Bleeding likely to occur in large varices or those with red signs at endoscopy and in severe lives disease
- Tend to develop in lower oesophagus and gastric cardia.
What are the causes of oesophagi-gastric varices?
Pre-hepatic: • Portal vein thrombosis. Intra-hepatic: • Cirrhosis (most common cause in UK) • Schistosomiasis (most common cause worldwide) • Sarcoidosis • Congenital hepatic fibrosis. Post-hepatic: due to venous blockage outside of the liver • Budd-Chiari syndrome (hepatic vein obstruction by tumour or thrombosis) • Right HF • Constrictive pericarditis • IVC obstruction.
What is the pathophysiology of varices?
At the oesophago-gastric junction, rectum and anterior abdominal wall (via umbilical vein) the portal and systemic capillary beds meet. If portal hypertension is present, the blood takes the path of least resistance which is through the systemic circulation and so bypasses liver and into heart. This causes detoxification and nutrition issues. As portal pressure increases, it can cause a gastric-oesophageal varices to form and rupture which cause massive haemorrhage.
Simply: as these vessels are thin and not meant to transport higher pressure blood, they can rupture. Rupture causes haematemesis and can also mean blood is digested which causes melaena.
What are the symptoms of varices?
- Haematemesis
- Abdominal pain
- Rectal bleeding.
What are the signs of varices?
- Hypotension
- Tachycardia
- Pallor
- Signs of chronic liver disease jaundice, easy bruising (liver not produced coagulation factors) and ascites
- Splenomegaly
- Ascites.
What is the investigation for varices?
Endoscopy.
What is the management for varices?
Blood transfusion if anaemic.
Medical:
• Beta blocker to reduce CO and so reduce portal pressure
• Nitrate to cause vasodilation and so reduce portal pressure
• Terlipressin (ADH analogue) to reduce portal pressure
Trans-jugular intrahepatic portoclaval shunt (TIPS).
Correct clotting abnormalities with vitamin K and platelet transfusion.
Variceal banding: band put around varice using endoscopy.
When does alcoholic liver disease typically present?
In men aged 40-50s.
What is the simple pathophysiology of alcoholic liver disease?
- Fatty liver to alcoholic hepatitis to alcoholic steatosis to cirrhosis
- Reduced NAD+ and increased NADH in hepatocytes so less oxidation of fat and more fat synthesis which causes accumulation of fat in hepatocytes
- Increased reactive oxygen species damages hepatocytes
- Acetaldehyde reactive oxygen species damages hepatocytes
- Leads to inflammation and eventual cirrhosis.
What is the pathophysiology of alcoholic liver disease?
Fatty liver (steatosis):
• Metabolism of alcohol produces fat in liver
• Cells become swollen with fat (steatosis) with larger amounts
• Fat disappears on alcohol abstinence
• In some cases, collagen is laid down around central hepatic veins which causes cirrhosis without preceding hepatitis
• Alcohol directly affects stellate cells, transforming them into collagen-producing myofibroblast cells
• May progress to fibrosis and cirrhosis if alcohol is not stopped
• Hepatocytes contain macrovesicular droplets of triglycerides on biopsy
• Possibly as a result of mitochondrial damage.
Alcoholic hepatitis:
• In addition to fatty change, there is infiltration by polymorphonuclear leukocytes and hepatocyte necrosis
• If alcohol consumption continues, alcoholic hepatitis can progress to cirrhosis. They usually coexist
• Presence of mallary bodies and giant mitochondria
• Ballooned hepatocytes that contain eosinophilic material called Mallory bodies, surrounded by neutrophils. Fibrosis and foamy degeneration of hepatocytes is possible
Alcoholic cirrhosis:
• Classically of the micronodular type, accompanying fatty change and evidence may be present
• Final stage of alcoholic liver disease
• Destruction of liver architecture and fibrosis
• Regenerating nodules bring micronodular cirrhosis
• Mallory bodies also present.
What are the symptoms of fatty liver?
Usually no symptoms. Possible hepatomegaly on examination.
What are the symptoms of alcoholic hepatitis?
Rapid onset jaundice. Nausea, anorexia, encephalopathy, fever and ascites.
What are the symptoms of alcoholic cirrhosis?
May be asymptomatic. Usually present with complications of cirrhosis. Spider naevei are a classic.
What are the symptoms of alcoholic liver disease?
- RUQ pain
- Nausea
- Vomiting
- Diarrhoea.
What do LFTs show in alcoholic liver disease?
GGT and ALP very raised. AST and ALT mildly raised (increased AST>ALT ratio which is usually 2:1).
What does FBC show in alcoholic liver disease?
• FBC: thrombocytopenia (low platelets), hypoglycamia (low blood sugar), raised MCV.
What is the management for alcoholic liver disease?
Alcohol abstinence because if alcohol intake stops then fat will disappear, and liver goes back to normal.
Diazepam to treat delirium tremens after alcohol withdrawal.
IV thiamine to prevent Wernicke-Korsafodd encephalopathy.
Corticosteroids to control inflammation if there is no renal failure.
Diet high in vitamins and proteins.
What are complications in alcoholic liver disease.
Delirium tremens (withdrawal symptoms) commonly seen 12-48 hours after alcohol withdrawal: seizures, insomnia, vomiting, headache, sweating, palpitations and tremulousness. Treated with diazepam.
Wernicke-Korsakoff encephalopathy. Triad of: • Confusion • Ataxia • Nystagmus. Give IV thiamine to prevent.
What is non-alcoholic fatty liver disease likely caused by?
Insulin resistance.
Who does non-alcoholic fatty liver disease affect?
Affects individuals with metabolic syndromes: • Obesity • Hypertension • Diabetes • Hyperlipidaemia • Hypertriglyceridaemia.
What are the risk factors for non-alcoholic fatty liver disease?
- Obesity (70%)
- Diabetes (35-75%)
- Hyperlipidaemia (20-80%).
What is the pathophysiology of non-alcoholic fatty liver?
Results from fat deposition in the liver.
Healthy -> steatosis -> steatohepatitis -> fibrosis and cirrhosis.
Non-alcoholic steatohepatitis (NASH) is fat sometimes with inflammation and fibrosis. Is an important cause of “cryptogenic” cirrhosis.
What are the symptoms of non-alcoholic fatty liver?
Usually no symptoms, liver ache in 10%. • Fatigue and malaise • RUQ pain • Jaundice • Hepatomegaly.
What do LFTs show in non-alcoholic fatty liver?
Commonest cause of mildly elevated LFTs, raised ALT and sometimes AST.
What investigation distinguishes between NASH and NAFL?
Liver biopsy.
What is the management for non-alcoholic fatty liver?
Still no effective drug treatments. Weight loss works, the more the better.
What is acute pancreatitis?
Sudden inflammation and haemorrhaging of the pancreas due to its own digestive enzymes (autodigestion). Usually reversible.
What are the causes of pancreatitis?
Remember I GET SMASHED: I diopathic G all stones E thanol (alcohol) T rauma (kinfe wound injury) S teroids M umps/malignancy A utoimmune e.g. SLE S corpion stings H hyperlipidaemia and hypercalcaemia E ndoscopic retrograde cholangiopancreatography D rugs e.g. azathioprine, metronidazole, tetracycline, furosemide.
What is the pathophysiology of acute pancreatitis?
The pancreases releases exocrine enzymes that cause autodigestion of the organ. Final common pathway is increased intracellular calcium which causes the activation of intra-cellular proteases and the release of pancreatic enzymes. This can lead to acinar cell injury and necrosis which causes inflammatory cells and the release of mediators and cytokines to produce local inflammatory response. Can progress to multiple organ failure.
What is the pathophysiology of alcoholic induced acute pancreatitis?
- Increases zymogen secretion from acinar cells while decreasing fluid and bicarbonate in the ducts so thick and viscous pancreatic juice which can obstruct the pancreatic duct
- Blocked duct causes pancreatic juices to become backed up which increases pressure and may distend the ducts
- Zymogen granules may fuse with lysosomes which brings trypsinogen into contact with lysosomal enzymes converting it to trypsin and so digestive enzyme cascade activation and autodigestion of pancreas (acute pancreatitis)
- Alcohol also stimulates cytokine release so immune response and neutrophils release superoxides and proteases.
What is the pathophysiology of gallstone induced pancreatitis?
- Become lodged in the sphincter of Odi which blocks release of pancreatic juices
- Block the bile duct causing back pressure in the pancreatic duct
- Similar to alcohol.
What are the symptoms of acute pancreatitis?
- Epigastric pain radiating to the back, relieved by sitting forwards
- Nausea and vomiting
- Coma and multiple organ failure are possible and may delay diagnosis.
What are the signs of acute pancreatitis?
- Cullen’s sign (bruising around periumbilical region), this ecchymoses suggests necrotising
- Grey Turner’s sign (bruising on flanks), this ecchymoses suggests necrotising
- Tachycardia
- Abdominal guarding and tenderness
- Distension.
What enzyme is massively raised in acute pancreatitis?
Amylase.
What do the LFTs show in acute pancreatitis?
- Raised serum amylase (3x more than normal)
- Raised serum lipase (more sensitive than amylase)
- Lipase to amylase >2 suggests alcoholic
- Raised ALT and AST
- Elevated ALT >150 suggests gallstones.
What would show on an abdominal X-ray in acute pancreatitis?
Abdominal X-ray shows no psoas shadow (raised retroperitoneal fluid).
What is the management for acute pancreatitis?
- NG tube
- IV fluid and maintain electrolyte balance
- Pain relief
- May need bowel rest
- Treat complications.
What are the complications of acute pancreatitis?
- Acute respiratory distress syndrome is the leading cause of death
- Sepsis
- Pancreatic pseudocyst
- Hypovolaemic shock from ruptured vessels
- DIC
- Pancreatic necrosis
- Pancreatic ascites
- Pancreatic abscess.
What is chronic pancreatitis?
Persistent inflammation due to structure changes such as fibrosis, atrophy and calcification. Generally irreversible.
What are the 2 types of chronic pancreatitis?
- Large duct pancreatitis
* Small duct pancreatitis: tends not to be associated with calcification.
What care the causes of chronic pancreatitis?
- Repeated bouts of acute pancreatitis
- Alcohol abuse
- Cystic fibrosis (main cause in children)
- Tumours
- Pancreatic trauma (knife wound).
What is the pathophysiology of chronic pancreatitis?
Inappropriate activation (possibly prompted by alcohol) of enzymes within the pancreas leads to precipitation of protein plugs within the duct lumen, forming a nidus for calcification. This leads to ductal hypertension, and therefore pancreatic damage. In addition to cytokine activation, this causes pancreatic inflammation, morphological change and possible permanent loss of function. End result is pancreatic fibrosis.
With each bout of acute pancreatitis there is the potential for ductal dilatation and damage to pancreatic tissue.
Stellate cells lay down fibrotic tissue which causes narrowing of ducts and acinar cell atrophy.
In conditions like alcoholic acute pancreatitis, calcium deposits of various sizes can accumulate on plugs that form the ducts.
Healthy tissue is replaced by misshapen ducts, fibrosis and calcium deposits is chronic pancreatitis.
What are the symptoms of chronic pancreatitis?
- Epigastric pain that radiations to back, may be linked to eating meals
- Nausea and vomiting.
What are the signs of chronic pancreatitis?
Jaundice possible due to obstruction of the common bile duct.
Malabsorption due to endocrine dysfunction:
• Weight loss
• Steatorrhea
• Vitamin deficiency.
Exocrine dysfunction:
• Diabetes mellitus.
These are due to insulin and lipase deficiency.
What are the investigations in chronic pancreatitis?
- CT abdomen
- Abdominal ultrasound
- Abdominal X-ray to show calcifications
- ERCP/MRCP
- Bloods: may show low lipase and amylase as there may not be enough healthy tissue to make the enzymes. Faeceal elastase.
What is the management for chronic pancreatitis?
Lifestyle modification: less alcohol, healthier diet, more exercise.
Pain control.
Replace digestive enzymes (aids functionality and pain by down regulating the release of pancreatic enzymes) and nutritional supplements.
Insulin for diabetes.
Local resection to alleviate duct dilatation/duct stones.
What is the complication of chronic pancreatitis?
Diabetes.
What is biliary colic?
The term used for pain associated with the temporary obstruction of the cystic or common bile duct by a stone migrating from the gall bladder.
What are the symptoms of biliary colic?
The pain of stone-induced ductular obstruction is of sudden onset, severe but constant and has a crescendo characteristic.
Pain is temporary and stops when gallstone dislodges.
What is cholecystitis?
Inflammation of the gallbladder.
What causes cholecystitis?
Gallstone impaction into the cystic duct or gallbladder neck.
What is the pathophysiology of cholecystitis?
Large fatty meals stimulate CCK which signals bile release from the gall bladder. When the GB has a gallstone in it, the squeezing of the GB can get it lodged in the cystic duct. Bile stasis becomes a chemical irritant and stimulates mucosa in wall to release mucus and inflammatory enzymes which causes inflammation, distension and pressure build up. Bacteria can start to grow e.g. E. coli and invade into gallbladder wall to cause peritonitis.
What are the symptoms of cholecystitis?
- Midepigastric to RUQ pain
- Fever
- Nausea and vomiting.
What are the signs of cholecystitis?
- Murphy’s sign: tenderness that is worse on inspiration
* Muscle guarding.
What investigations are performed in cholecystitis?
- Ultrasound of abdomen
- FBC: high WBC count (leucocytosis)
- LFTs: to exclude liver/bile duct pathology.
What is the management of cholecystitis?
- Laparoscopic cholecystectomy
* Analgesia and fluids if needed.
What is the complication of cholecystitis?
Peritonitis.
What generally causes ascending cholangitis?
Gallstones.
What are the causes of ascending cholangitis?
Generally caused by gallstones.
Infection of the biliary tree e.g. E.Coli, Klebsiella, enterococcus (group D strep). Most often secondary to common bile duct obstruction by gallstones (choledocholithiasis).
Benign biliary strictures, often following surgery, malignancy or associated chronic pancreatitis.
Primary sclerosing cholangitis.
What are the risk factors for ascending cholangitis?
- Fair (Northern European and Hispanic)
- Female
- Fat (obese)
- Fertile (pregnancy, under 40).
What is the pathophysiology of ascending cholangitis?
Normally bacteria can’t go up the common bile duct as bile and pancreatic juices travel down and flush bacteria out. Obstruction of the common bile duct causes stasis of bile and invasion of bacteria from duodenum. This increases susceptibility to infection. High pressure on the common bile duct due to obstruction can causes spaces between the cells which allows the bacteria and the bile access to the blood stream which can cause bacteraemia and jaundice.
Can be obstructed by stone, cancer, stricture, parasite (ascaris). Also, infection can be introduced through intervention e.g. ERCP.
What are the symptoms of ascending cholangitis?
Charcot’s triad:
• Jaundice: dark urine and pale stools
• RUQ pain
• Fever.
What are the signs of ascending cholangitis?
Reynold’s pentad: • Jaundice • RUQ pain • Fever • Shock: hypotension and tachycardia • Confusion (bacteraemia causes septic shock so leaky vessels and hypotension so less blood to organs such as the brain and confusion).
Also rigors.
What is the definitive investigation for ascending cholangitis?
Endoscopic Retrograde Cholangiopancreatography (ECRP).
Can remove blockage.
What is very high if there is a bile duct obstruction?
Bilirubin.
What are the investigations in ascending cholangitis?
- Ultrasound abdomen to detect stone/stent/stricture
- FBC: raised WBCs, ESR and CRP, raised serum bilirubin (very high if bile duct obstruction) and serum alkaline phosphatase, ALP, AST, ALT
- ERCP is definitive. Can remove blockage
- Magnetic resonance cholangiopancreatography (MRCP) to locate stone
- LFTs
- CT
- Blood culture if septic.
What are the differentials for ascending cholangitis?
Biliary colic: RUQ pain only
Cholecystitis: RUQ pain and maybe fever.
What is the management for ascending cholangitis?
- IV antibiotics e.g. co-amoxiclav
- Fluids
- ERCP (endoscopic retrograde cholangiopancreatography to image/stent/remove stone
- Shockwave lithotripsy
- If this fails then laparoscopic/open cholecystectomy.
What is the complication of ascending cholangitis?
Sepsis.
What does bile contain?
Bile contains cholesterol, bile pigments (broken down from Hb) and phospholipids.
When do gallstones typically present?
<30. More common in Females.
What are the 2 types of gallstone?
Cholesterol gallstones (more common):
• Cholesterol supersaturation
• Nucleation factors
• Reduced gallbladder motility.
Pigmen gallstones:
• Chronic haemolysis (sphereocytosis and sickle cell) in which bilirubin production is increased
• Cirrhosis
• Possible as a complication of cholecystectomy and with duct strictures.
What are the risk factors for gallstones?
- Female
- Fat
- Fertile (pregnancy)
- Family history
- Forty (age)
- Obesity
- Smoking.
What is the pathophysiology of cholesterol gallstones?
- Cholesterol is held in solution by detergent action of bile salts and phospholipids which forms micelles and vesicles
- Only form in bile which has an excess of cholesterol (lithogenic bile) where there is a relative lack of bile salts and phospholipids
- The formation of cholesterol crystals and gallstones in lithogenic bile is promoted by factors that favour nucleation such as mucus and calcium
- Gallstone formation further promoted by reduced gallbladder motility and stasis.
What is the pathophysiology of pigment gallstones?
- Consist of bilirubin polymers and calcium bilirubinate
- Caused by excess of bilirubin
- Seen in patients with chronic haemolysis (e.g. hereditary spherocytosis and sickle cell disease) in which bilirubin production is increased and cirrhosis
- Pigment stones may also form in bile ducts after.
What are the symptoms of gallstones?
Majority of gallstones are asymptomatic.
Biliary or gallstone colic: sudden, severe but constant epigastric pain (may have a RUQ component and may radiate over right shoulder and scapular region). Pain usually increases for around 15 minutes, stays constant for a few hours then decreases once the stone has dislodged. Starts several hours after a meal. May be worse at night. Caused by a gallstone impacting on the cystic duct or the ampulla of vater.
Second most common is acute cholecystitis where distension of the gallbladder causes necrosis and ischaemia.
Nausea and vomiting and sweating.