ALF CLF Flashcards
Definition of acute liver failure
Acute liver failure is a syndrome of acute liver dysfunction without underlying chronic liver disease.
ALF characterised by + Key presentations
Coagulopathy
HE
3 subtypes of ALF
- Hyperacute: HE within 7 days of noticing jaundice. Best prognosis as much better chance of survival and spontaneous recovery.
- Acute: HE within 8-28 days of noticing jaundice
- Subacute: HE within 5-12 weeks of noticing jaundice (ALF may be defined up to 28 weeks). Worst prognosis as usually associated with shrunken liver and limited chance of recovery.
Epidemiology of ALF
ALF is the primary indication for liver transplantation in around 8% of cases within Europe.
Acute liver injury (ALI): severe acute liver injury from a primary liver aetiology. Characterised by impaired liver function but hepatic encephalopathy is absent, unlike in ALF that cause ALF
- Viral (Hepatitis A, B and CMV) - most common worldwide
- Other infections e.g. yellow fever, leptospirosis, EBV
- Drug-induced liver injury - paracetamol and non-paracetamol (e.g. alcohol, anti-depressants, NSAIDs)
- Wilsons
- Budd chiari
- Toxin induced
Secondary liver injury (SLI): similar to ALI but no evidence of a primary liver insult that cause ALF
- Ischaemic hepatitis
- Liver resection(post-hepatectomy liver failure)
- Severe infection(e.g. malaria)
- Malignancy infiltration(e.g. lymphoma)
- Heat stroke
ALF pathophysiology
DIrect liver insult > massive hepatocyte necrosis and apoptosis > liver doesnt carry out normal function
As ALF progresses what happens
hyperdynamic circulatory state with low systemic vascular resistance due to a profound inflammatory response
Causes poor peripheral perfusion and multi-organ failure
Marked cerebral oedema occurs in ALF what does this lead to
Morbidity and mortality in ALF
Due to hyperammonaemia causing cytotoxic oedema and increased cerebral BF
S + S of ALF
- HE - altered mental status, confusion
- Jaundice
- Right upper quadrant pain(variable)
- Hepatomegaly
- Ascites
Primary investigations of ALF
FBC
U&Es
LFTs
Blood Glucose
LDH
ABG
Imaging for ALF
- Ultrasound - to see liver size and underlying liver pathology
- Doppler ultrasound - to assess patency of hepatic and portal veins
- Chest x-ray
- CT abdomen and pelvis - examine liver architecture, volume, vascular integrity etc
Management of ALF
- Treat underlying cause
- Good nutrition - thiamine and folate supplementation
Major complications of ALF
- Acute kidney injury/ hepatorenal syndrome
- Metabolic disturbance
- Hypoglycaemia
- Haemorrhage (e.g. GI Bleeding)
- Cerebral dysfunction (e.g. seizures, irreversible brain injury).
- Patients are at risk of high output cardiac failure due to low vascular resistance from the widespread inflammatory response.
- Sepsis
Definition of CLD
Chronic liver disease is caused by repeated insults to the liver, which can result in inflammation, fibrosis and ultimately cirrhosis.
CLD is generally defined as progressive liver dysfunction for six months or longer. The end result of chronic liver disease is cirrhosis, which describes irreversible liver remodelling.