=====Acute Liver Failure=====
  *A specific term used to refer to:
    * acute abnormality of [[wiki:labs:#Liver_Function_Tests|Liver Function Tests]] in someone //**without underlying liver disease**// as opposed to Acute on Chronic Liver disease and others
    * is associated with a coagulopathy which is different from the coagulopathy of sepsis. The coagulopathy required is determined as: INR >1.5 or prolonged PT
    * and have altered consciousness.
  *'ALF' with coagulopathy but no change in consciousness is termed //**Acute Liver Injury**//
  *ALF begins as ALI with 2 to 3 fold increase in transaminases, coagulopathy and jaundice

<WRAP round box>__Exceptions to the 'previous liver disease' rule__ include: the //de novo// presentation of autoimmune hepatitis, Budd-Chiari syndrome and Wilson disease as these will not have been diagnosed before, and those patients who have evidence of liver pathology but did not have //overt// disease. They all share the same poor prognosis.</WRAP>

[{{ :wiki:gastroenterology:acliverfailureclasses.jpeg?400| //**Different classification systems for Acute Liver Failure**//}}]

^  Acute Liver Failure is often graded:  ||
^hyperacute  |• <10/7 from onset of jaundice to encephalopathy\\ • severe coagulopathy\\ • markedly increased transaminases\\ • modest if any increase in Bilirubin  |
^acute/fulminant  |• 10-30/7 from onset of jaundice to encephalopathy\\  |
^subacute  |• 5-24/52 from onset of jaundice to encephalopathy\\ • mild/moderate coagulopathy\\ • milder increase in transaminases\\ • deep jaundice\\ • often have splenomegaly, ascites  |


^Classification of Hepatic encephalopathy (West Haven criteria) ||
^Stage ^Clinical |
^I |Euphoria, depression, some disorientation, slurred speech, sleep disturbance, may have asterixis|
^II |Lethargy, moderate disorientation, asterixis |
^III |marked disorientation, can be roused when somnolent, asterixis |
^IV |coma, initially reacting to painful stimuli |

----
**Management, especially transplant, is then dependent on aetiology:**
  *malignant infiltration
  *hypoxic/ischaemic - AST +++ (usually >2x ALT), often with normal Bili (similar to Paracetamol OD picture)
  *other systemic and infective related - autoimmune, malaria, dengue, rickettsiosis, viruses and fungi
  *HepB, HepA and HepE
  *some toxins - yellow phosphorous
  *drugs - paracetamol, anti TB agents, antibiotics (nitrfuratoin, ketokonazole), antiepileptics (phenytoin, valproate), NSAIDs
  *other - unknown cause despite Ix

====Management====
  *fluid resuscitation and possibly vasopressors
  *attention to pre-emptive causes - ischaemia/hypoxia/OD etc
  *administration of coagulation factors is not advised
  *ulcer prophylaxis
  *N-acetyl cysteine if paracetamol OD
  *treatment or prevention of encephalopathy is problematic - regimens to treat ↑ammonia levels in chronic liver disease have not been beneficial in prevention in the acute illness
  ***liver transplant** (the only curative Rx) based on scoring systems - eg. Kings' College, Clichy criteria, MELD, CK/modified MELD, BiLE score


^  Kings' College criteria  ||
^Paracetamol OD |**art pH <7.25**.. or 2 of:\\ • INR<6.5\\ • C>300μmol/L\\ • encephalopathy grade 3-4|
^other causes |**INR>6.5**.. or 3 of:\\ • age<10 or >40y\\ • aetiology unclear or medication\\ • INR>3.5\\ • Bili >300μmol/L|

===MELD score===
  *The Model for End-Stage Liver Disease, or MELD, is a scoring system for assessing the severity of chronic liver disease
  *MELD uses the patient's values for serum bilirubin, serum creatinine, and the international normalized ratio for prothrombin time (INR) to predict survival. Calculated according to the following formula:
    *MELD = 3.78×ln[serum bilirubin (mg/dL)] + 11.2×ln[INR] + 9.57×ln[serum creatinine (mg/dL)] + 6.43 (conversion from μmol/L to mg/dl, multiply by 0.0113. To convert mg/dl to μmol/L, multiply by 88.4)
MELD scores are reported as whole numbers, so the result of the equation above is rounded.

===Child-Pugh score===
  *used to assess the prognosis of chronic liver disease, mainly cirrhosis
  *5 clinical measures of liver disease with each measure scored 1–3, with 3 indicating most severe derangement. Either the PT or INR should be used not both.

^Measure ^1 point ^2 points ^3 points |
^Total bilirubin, μmol/L (mg/dL) |< 34 (< 2) |34–50 (2–3) |> 50 (> 3) |
^Serum albumin, g/dL |> 3.5 |2.8–3.5 |< 2.8 |
^Prothrombin time, prolongation (s) |< 4.0 |4.0–6.0 |> 6.0 |
^INR |< 1.7 |1.7–2.3 |> 2.3 |
^Ascites |None |Mild (or suppressed with medication) |Moderate to severe (or refractory) |
^Hepatic encephalopathy	|None |Grade I–II |Grade III–IV |
  *Chronic liver disease is classified into Child–Pugh class A to C, employing the added score from above

^Points ^Class ^One-year survival ^Two-year survival |
^5–6 |A |100% |85% |
^7–9 |B |80% |60% |
^10–15 |C |45% |35% |

==References include:==
[[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221437/|Acute Liver Failure review 2011]]\\ 
[[https://www.nejm.org/doi/full/10.1056/NEJMra1208937|Acute Liver failure review NEJM 2013]]\\ 
[[https://easl.eu/wp-content/uploads/2018/10/LiverFailure-English-report.pdf|Management of Acute Liver Failure: Journal of Hepatology 2017]]\\