Liver and friends Flashcards
(133 cards)
Liver failure definition
Hepatic failure occurs when the liver loses the ability to regenerate or repair, so that decompensation occurs. It is characterised by:
- hepatic encephalopathy
- abnormal bleeding
- ascites
- jaundice
Liver failure epidemiology
Globally, viral infection accounts for the majority of cases of liver failure, however, paracetamol overdose is the leading cause in the UK.
Liver failure aetiology
Toxins - chronic alcohol abuse, paracetamol poisoning
Infections - viral heapatitis, adenovirus, epstin-barr virus
Neoplastic - hepatocellular carcinoma or metastatic carcinoma
Metabolic - Wilson’s disease, alpha-1-antitrypsin deficiency
Pregnancy-related - acute fatty liver of pregnancy
Vascular - ischaemia or veno-occlusive disease, Budd-Chiari syndrome
Others - autoimmune liver disease (PBC, PSC), unknown cause - 15%
Liver failure pathophysiology
Dependent on cause
Liver failure signs and symptoms
Mental state showing dowsiness and possibly confusion
Jaundice
Abdominal distention and abdominal masses including:
- possible massive ascites and anasarca (general swelling) due to fluid distribution and hypoalbuminemia
- hepatomegaly and splenomegaly
Cerebral oedema with increased ICP may produce papilloedema (optic disc swelling, seen on fundoscopy)
Liver palms (palmar erythema [reddening of the thenar and hypothenar eminences])
Asterixis (tremor on wrist extension)
Signs of hepatic encephalopathy
Liver failure 1st line investigations
Bloods:
- likely to see iron-deficient anaemia
- may show thrombocytopenia (low platelets)
- raised INR
- markedly raised transaminases (AST and ALT) but alkaline phosphate may be high or normal
- raised bilirubin
- high ammonia
- glucose can be dangerously low
- blood cultures - patients are very susceptible to infection
Imaging:
- doppler ultrasound - look for patents hepatic vein, carcinoma and ascites
- imaging of the head - cerebral oedema
Liver failure management
Conservative: fluids and analgesia
Possibility of liver transplantation should be considered at an early stage
Underlying cause should be assessed and managed
Treat complications:
- ascites - diuretics
- cerebral oedema - Mannitol
- bleeding - Vitamin K
- encephalopathy - Lactulose
- sepsis - sepsis 6, antibiotics
- hypoglycaemia - dextrose
Liver failure complications
Infection is a big problem - spontaneous peritonitis is common
Cerebral oedema may be associated with intracranial hypertension and death
Haemorrhage from oesophageal varices is a major complication
Cholelithiasis (gallstones) definition
The presence of solid concretions in the gallbladder. Usually form in the gallbladder but may enter into the bile ducts (choledocholithiasis). Symptoms occur if a stone obstructs the cystic, bile or pancreatic ducts. In the developed world most gallstone are made of cholesterol.
Cholelithiasis (gallstones) aetiology
Mostly due to cholesterol composed stones forming in the gallbladder.
Around 5% of gallstone are black pigment stones. These consist of polymerised calcium bilirubinate. Patients with chronic haemolytic anaemia, cirrhosis. cystic fibrosis and ilial disease are at a higher risk of black pigment stones.
Brown pigment gallstones result from stasis and infection and form in the bile ducts. May be due to bacterial infection or biliary parasites although in the west they are more commonly from biliary stricture, either inflammatory or neoplastic.
Cholelithiasis (gallstones) risk factors
Age, female sex, overweight, oestrogen (pregnancy/exogenous)
Cholelithiasis (gallstones) pathophysiology
Symptoms and complications result when stones obstruct the cystic and/or bile ducts. Transient obstruction of the cystic duct results in biliary pain (biliary colic). More persistent obstruction leads to acute cholecystitis (inflammation of the gallbladder).
Mirizzi syndrome is an uncommon condition where a large gallstone is impacted in the cystic duct or neck of the gallbladder, compresses the common bile duct and causes obstruction and jaundice.
If gallstones pass into the bile ducts causing obstruction, the result can be biliary and acute cholangitis (inflammation of the bile duct system)
Stone passage through the distal bile duct cab culminate in obstruction at the ampulla. Acute biliary pancreatitis results from the increase in pancreatic ductal pressure and reflux of pancreacticobiliary scretions into the pancreatic duct.
If a gallstone erodes through the gallbladder wall, a cholecystoenteric fistula can develop leading to duodenal obstruction (Bouveret syndrome) or obstruction in the narrowest segment of an otherwise healthy bowel causing gallstone ileus.
Cholelithiasis (gallstones) signs and symptoms
Gallstones themselves are common and are usually asymptomatic unless causing obstruction and/or inflammation.
Right upper quadrant or epigastric pain is the most common symptom of cholelithiasis and is caused by obstruction of the cyctic duct or obstruction and/or passage of a gallstone through the common bile duct.
Biliary pain:
- radiated to the right back or shoulder
- responds to analgesia
- often occurs 1hr after food
- may have associated nausea and vomiting
- becomes increasingly intense then stabilizes
These symptoms together with fever and abdominal tenderness (Muphy’s sign: pain on palpation during inspiration) indicates the development of acute cholecystitis. A distended, tender gallbladder may be palpable in acute cholecystitis
Cholelithiasis (gallstones) 1st line investigations
Biliary colic due to a stone in the neck of the gallbladder or cystic duct is unlikely to be associated with significant abnormalities of tests. Acute cholecystitis is usually associated with moderate leukocytosis and raised inflammatory markers (eg CRP).
FBC - leukocytosis with AC
Bilirubin - may be raised. More significant elevation is consistent with bile duct obstruction
LFTs - elevated alkaline phosphate is consistent with bile duct obstruction
Serum lipase or amylase - identify or exclude acute pancreatitis
Blood cultures - if infection is suspected
Cholelithiasis (gallstones) gold standard investigations
Abdominal ultrasound scan
- may show gallstones, distended gallbladder, thickened gallbladder was
May follow up with MRCP if no bile duct stone seen
Endoscopic retrograde cholangiography - better but less commonly used
Cholelithiasis (gallstones) differential diagnosis
Acute cholangitits: classic findings are fever and chills, jaundice and abdominal pain (charcot’s triad)
Chronic cholecystitis
Peptic ulcer disease
Acute pancreatitis - serum amylase and lipase, inflammation on CT scan
Cholelithiasis (gallstones) management
Analgesia
IV fluids if needed
Antiobiotic therapy (if suspected sepsis)
Laparoscopic cholecystectomy
Percutaneous cholecystostomy if unfit for anaesthesia and surgery
Cholelithiasis (gallstones) prognosis
Intreated acute acalculous cholecystitis has mortality up to 50%
Acute cholangitis defintiion
Previously known as ascending cholangitis, acute cholangitis is an infection of the biliary tree most commonly used by obstruction
Acute cholangitis aetiology
- most common aetiology is cholelithiasis (gallstones) leading to choledocholithiasis (gallstones in the bile duct) and biliary obstruction
- iatrogenic biliary injury leading to strictures of the biliary tree
- sclerosing cholangitis cause up to a quarter of cases
- chronic pancreatitis (with stenosis and stricture of the distal common bile duct)
- radiation-induced biliary injury
- complication of chemo
Acute cholangitis risk factors
Age, gallstones, strictures, surgery on the biliary system
Acute cholangitis pathophysiology
Obstruction of the common bile duct initially results in bacterial seeding of the biliary tress, possibly via the portal vein, and when combined with bacterial contamination, can lead to acute cholangitis. As the bile duct pressure increases, extravasation of the bacteria into the bloodstream occurs. If not recognised and treated this will lead to sepsis.
Acute cholangitis key presentations
Classic presentation is Charcot’s triad: fever jaundic and right upper quadrant pain. Pale stool, pruritus (itch associated with liver disease)
Acute cholangitis 1st line investigations
Transabdominal ultrasound - if there are signs of severe cholangitis or patient is high risk for sepsis
Subsequent abdominal CT scan if ultrasound is inconclusive.
Bloods
- FBC - look at white count
- coagulation profile - PT may be raised with sepsis
- CRP - raised
- LFTs - raised
- U&Es - raised urea with severe disease
- blood cultures - usually gram -ve
Arterial blood gas including lactate is spesis is suspected - low bicarbonate with raised anion gap; metabolic acidosis; raised lactate