GC025 A Jaundiced And Incoherent Patient Liver Failure
Liver failure is a severe deterioration of hepatic function resulting in jaundice, hepatic encephalopathy (manifesting as confusion and incoherence), coagulopathy, and potential multiorgan dysfunction due to the liver's inability to perform its synthetic, metabolic, and detoxification functions.
A Jaundiced and Incoherent Patient: Liver Failure
This lecture by Prof. Wai-Kay Seto covers the clinical scenario of a patient presenting with jaundice and altered mental state — the classic presentation of liver failure with hepatic encephalopathy. It is one of the most commonly tested GC topics because it integrates pathophysiology, data interpretation (LFT, INR, ammonia), prognostic scoring (Child-Pugh, MELD, King's Criteria), and emergency management.
How the lecture fits in:
- GC 025 focuses on liver failure definitions, categorization, etiologies, prognostic factors, hepatic encephalopathy (precipitants, diagnosis, grading, management), coagulopathy, and ALF management.
- GC 026 (next lecture) covers the downstream complications of cirrhosis — ascites, SBP, varices, hepatorenal syndrome, portal hypertension, HCC.
- Together, GC 025 + 026 form the complete liver failure–cirrhosis–complications arc.
Learning Objectives (from slides):
- Define and categorize liver failure (ALF vs ACLF vs decompensated cirrhosis)
- Understand aetiologies of each category
- Know prognostic scoring systems and their limitations
- Understand the pathogenesis, grading, diagnosis, and management of hepatic encephalopathy
- Manage complications of liver failure (infections, coagulopathy, cerebral oedema)
- Know specific treatments for ALF causes (NAC, antivirals, activated charcoal)
Do not merge the two HE pathways
The lactulose–rifaximin pathway in this note is for overt HE in cirrhosis/portosystemic shunting. In acute liver failure, conventional ammonia-lowering therapy has no established evidence base and lactulose can cause ileus/bowel distension; neurological monitoring, airway protection, cerebral-oedema prevention and urgent transplant-centre care take priority. [10]
1. Liver Failure: Definitions and Categorization
Liver failure is categorized into three types: Acute Liver Failure (ALF), Acute-on-Chronic Liver Failure (ACLF), and Decompensated Cirrhosis. [1]
This is the fundamental framework. Each category has different aetiologies, different prognostic tools, and different management strategies.
ALF = Development of severe acute liver injury with encephalopathy and impaired synthetic function (INR ≥ 1.5) in a patient WITHOUT pre-existing cirrhosis/chronic liver disease, usually within an illness of < 26 weeks. [1,10,11]
Why each criterion matters:
- Encephalopathy: proves the liver injury is severe enough to cause systemic toxicity (ammonia crossing the blood-brain barrier)
- INR > 1.5: proves synthetic function is critically impaired — the liver can no longer make clotting factors (especially Factor VII, half-life ~6 hours, making PT/INR the most sensitive acute marker of liver synthetic failure) [2]
- No pre-existing cirrhosis: distinguishes ALF from ACLF — this distinction matters for prognosis and transplant criteria
| Subtype | Jaundice-to-Encephalopathy Interval | Cerebral Oedema | INR | Bilirubin | Prognosis |
|---|---|---|---|---|---|
| Hyperacute | 0–1 week | Common | Very prolonged | Least raised | Moderate |
| Acute | 1–4 weeks | Common | Prolonged | Raised | Poor |
| Subacute | 4–26 weeks | Infrequent | Less prolonged | Raised | Poor |
Key Clinical Feature
Clinical features of ALF are "not obvious" [1] — the lecture emphasizes this because unlike decompensated cirrhosis with ascites, spider naevi, etc., ALF patients may look deceptively well early on. Jaundice may even be late, especially in paracetamol poisoning. The INR is your sentinel marker.
Organ-by-organ clinical features of ALF (from lecture slide) [1]:
| Organ/System | Clinical Feature |
|---|---|
| Liver | Loss of metabolic function → ↓gluconeogenesis (hypoglycaemia), ↓lactate clearance (lactic acidosis), ↓ammonia clearance (hyperammonaemia), ↓synthetic capacity (coagulopathy) |
| Brain | Hepatic encephalopathy, cerebral oedema, intracranial hypertension |
| Kidney | Frequent dysfunction or failure |
| Lungs | Acute lung injury, ARDS |
| Heart | High-output state, frequent subclinical myocardial injury |
| Adrenal gland | Inadequate glucocorticoid production → contributes to hypotension |
| Bone marrow | Frequent suppression, especially in viral and seronegative disease |
| Circulating leucocytes | Impaired function and immunoparesis → high risk of sepsis |
| Pancreas | Pancreatitis, particularly in paracetamol-related ALF |
| Portal system | Portal hypertension may be prominent in subacute disease and can be confused with chronic liver disease |
| Systemic | Systemic inflammatory response, high energy expenditure and catabolism |
The slide uses the APASL-style description: an acute hepatic insult with jaundice and INR > 1.5, followed within 4 weeks by ascites and/or encephalopathy in a patient with underlying chronic liver disease. [1]
Critical points:
- There is no single universal ACLF definition. APASL centres the acute hepatic insult and short interval; EASL-CLIF centres acute decompensation plus organ failure; current AASLD guidance requires rapid deterioration in chronic liver disease plus liver failure and at least one extrahepatic organ failure. State which system you are using. [12,13]
- The chronic liver disease might be undiagnosed [1] — a patient may present for the first time with what appears to be ALF, but on investigation turns out to have pre-existing cirrhosis (e.g., splenomegaly on imaging, thrombocytopenia, stigmata of CLD on exam)
- 28-day mortality > 20% is part of the slide/APASL framing; reported short-term mortality varies substantially with the consortium definition and number of organ failures. [1,12]
This is covered in detail in GC 026 but is mentioned here as the third category. It represents the development of symptomatic cirrhotic complications (ascites, variceal bleeding, HE, HRS, HCC) in a patient with known chronic liver disease.
2. Aetiologies of Liver Failure
Drug-related causes are the most important: [1]
- Paracetamol overdose
- Idiosyncratic drug reactions
- Herbal-related
Acute viral hepatitis (HAV / HEV / acute HBV)
Pregnancy-related causes (acute fatty liver of pregnancy / HELLP syndrome) — rare
Why paracetamol is #1: Paracetamol is metabolized by CYP2E1 to NAPQI, which is normally detoxified by glutathione. In overdose, glutathione is depleted → NAPQI accumulates → direct hepatocyte necrosis. This is dose-dependent and predictable, unlike idiosyncratic reactions.
Why herbal hepatotoxicity is highlighted: Prof. Seto dedicates multiple slides to this because it is extremely relevant in the Hong Kong clinical context.
In the historical local cohort shown on the slide, HILI (herb-induced liver injury) accounted for 22% of 122 inpatient acute-hepatitis cases, equal to conventional DILI at 22%. [1]
-
102 types of hepatotoxic herbs have been reported in the literature [1]
-
This small, single-centre chart is local and more than a decade old; it illustrates clinical relevance but should not be quoted as current Hong Kong prevalence.
-
The photographed handwritten multi-herb prescription and the loose pills, capsules and branded products make the practical point: record the exact formula/product, ingredients if known, dose, start/stop dates, indication, prescriber/source and product batch/packaging. Ask the patient or family to bring photographs or the original container.
-
Herbal medications in tablet/capsule form are especially dangerous because patients may not consider them "medicines" and fail to report them
-
Always ask about herbal medicine, wild mushrooms and health supplements in the drug history. Many published herb–injury associations have variable causality strength, and multi-ingredient/adulterated products make culprit attribution difficult. [14]
Visual safety lesson: wild mushrooms
The newspaper images show that foraged-mushroom poisoning can progress from gastroenteritis to fulminant liver failure and transplantation. If amatoxin poisoning is possible, contact the poison-information/transplant service urgently; identify the specimen if this can be done safely and do not wait for liver injury before specialist management.
Exam Trap
When a question says "unremarkable past health" with ALF, and lists possible causes — think paracetamol overdose, acute viral hepatitis, or herbal/drug injury. Do NOT pick "red wine 1 day prior" (alcohol rarely causes acute liver failure from a single episode) or "atorvastatin" (statins cause hepatotoxicity very rarely). See 2022 MCQ Q39 [3] — the answer was acute hepatitis E, not red wine or atorvastatin.
HBV-related: [1]
- Severe exacerbation of HBV
- Immunosuppressive agents (steroids, rituximab etc.)
Infections:
- Superimposed HAV / HEV
- Other systemic infections (Pneumonia / UTI / soft tissue etc.)
External agents:
- Alcoholic hepatitis
- Hepatotoxic drugs / herbs
Why immunosuppressants matter: In an HBV carrier, immunosuppressive therapy (especially rituximab, which depletes B cells) can cause massive HBV reactivation. This is why all patients should be screened for HBV before chemotherapy/immunosuppression.
Specific "Hepatotoxic" Drugs: [1]
- Paracetamol (overdose)
- NSAIDs
- Statins (actually very rare)
- Anti-TB drugs (isoniazid, rifampicin, pyrazinamide)
- Other antimicrobials
- Anticonvulsants
- Rheumatological (methotrexate, azathioprine)
- Amiodarone
Why this list matters: In any exam question where a patient develops deranged LFTs, you MUST screen this list. Anti-TB drugs are a particularly common exam scenario (isoniazid is the main culprit for hepatotoxicity; rifampicin can cause cholestatic hepatitis).
High Yield
Statins are listed as hepatotoxic but the lecture explicitly notes this is "actually very rare." [1] This is an exam discriminator — examiners may try to trick you into blaming statins for liver failure when another cause is more likely.
Systemic effects include: [1]
- General non-specific malaise
- Encephalopathy
- Ascites
- Jaundice (usually late stage)
- Fetor hepaticus (usually late stage)
- Circulatory changes: ↑CO, ↓peripheral resistance, ↓renal blood flow
- N₂ metabolism: ↑NH₃, ↓urea, amino acid abnormalities, ↓albumin
- Skin changes due to vasodilatation: spider angioma, palmar erythema
- Endocrine changes: hypogonadism, hyperaldosteronism
- Defective coagulation, ↓platelet, ↑fibrinolysis
Why each effect occurs — from first principles:
| Effect | Mechanism |
|---|---|
| Encephalopathy | ↓hepatic detoxification of ammonia → crosses BBB → astrocyte swelling |
| Ascites | Portal hypertension + ↓albumin (↓oncotic pressure) + hyperaldosteronism (Na/H₂O retention) |
| Jaundice (late) | Hepatocyte damage → ↓conjugation/excretion of bilirubin |
| Fetor hepaticus | Dimethyl sulfide from failed hepatic metabolism — sweet, musty smell |
| ↑CO, ↓PVR | Splanchnic vasodilation from NO/prostacyclins → effective hypovolemia → compensatory ↑CO |
| ↓Renal blood flow | Splanchnic vasodilation → ↓effective circulating volume → renal vasoconstriction (hepatorenal syndrome) |
| ↑NH₃, ↓urea | Failed urea cycle — liver cannot convert ammonia to urea |
| ↓Albumin | ↓hepatic synthetic function (albumin half-life ~21 days, so late marker) |
| Spider angioma / Palmar erythema | Hyperestrogenism from ↓hepatic estrogen metabolism → arteriolar vasodilation |
| Hypogonadism | ↑estrogen, ↓testosterone from failed hepatic metabolism + ↑SHBG |
| Hyperaldosteronism | ↓hepatic clearance of aldosterone + RAAS activation from ↓effective circulating volume |
| Haemostatic disturbance | ↓procoagulant factors and platelets occur alongside ↓natural anticoagulants, ↑vWF and endothelial/fibrinolytic changes; the net state may favour bleeding or thrombosis |
Important Caveat from Lecture
Vibration-controlled transient elastography (FibroScan) is the non-invasive method to stage fibrosis. [1]
Why this matters: Liver biopsy is the gold standard for fibrosis staging but is invasive (bleeding risk, sampling error). FibroScan measures liver stiffness in kPa — higher values indicate more fibrosis. It is widely used in Hong Kong for HBV/MASLD patients.
Fibrosis staging progression [1]:
- F1 — Portal fibrosis (isolated fibrosis around portal tracts)
- F2 — Portal fibrosis with few septa
- F3 — Septal fibrosis (multiple bridging septa)
- F4 — Cirrhosis (dense interconnected fibrous bands with nodule formation)
FibroScan example values [1]:
| Fibrosis Stage | Liver Stiffness (kPa) | Shear-Wave Velocity (m/s) |
|---|---|---|
| F0 (no fibrosis) | 3.0 | 1.0 |
| F2 (moderate fibrosis) | 7.7 | 1.6 |
| F4 (cirrhosis) | 27 | 3.0 |
These values are a visual demonstration, not universal diagnostic cut-offs. Liver-stiffness thresholds vary with aetiology, device and protocol; acute hepatitis/inflammation, cholestasis, venous congestion and a recent meal can transiently raise stiffness. Do not stage fibrosis from one number without the clinical context.
5. Prognostic Scoring Systems
Child-Pugh Score: [1]
| Parameter | 1 point | 2 points | 3 points |
|---|---|---|---|
| Bilirubin (µmol/L) | < 34 | 34–51 | > 51 |
| Albumin (g/L) | > 35 | 28–35 | < 28 |
| INR | < 1.7 | 1.7–2.3 | > 2.3 |
| Ascites | None | Mild | Refractory |
| Encephalopathy | None | Gr 1–2 | Gr 3–4 |
| Class | Score | Significance |
|---|---|---|
| A | 5–6 | Compensated; good prognosis |
| B | 7–9 | Significant functional compromise |
| C | 10–15 | Decompensated; poor prognosis |
For bilirubin: 1 mg/dL = 17.1 µmol/L [1]
Disadvantages of Child-Pugh: [1]
- Limited discrimination — only 8 levels between Child B and C
- Same score for different values of bilirubin, albumin, PT
- Subjective assessment of ascites and encephalopathy
- Variability of PT and albumin across laboratories
- Albumin and PT measurements can be "manipulated" (e.g., albumin infusion, FFP transfusion)
Exam Intelligence
The Child-Pugh score is asked in virtually every exam cycle. The 2021 SAQ Q5 [5] directly asked students to "Name TWO prognostic models that can be used to grade the severity of cirrhosis" — answer: Child-Pugh score and MELD score. Know the components cold.
MELD = 3.8 × logₑ(bilirubin mg/dL) + 11.2 × logₑ(INR) + 9.6 × logₑ(creatinine mg/dL) + 6.4 [1]
Very good in prediction of 3-month mortality, useful to prioritize patients for liver transplant. [1]
Why MELD is better than Child-Pugh:
- Uses only objective laboratory values (bilirubin, INR, creatinine) — no subjective ascites/encephalopathy grading
- Continuous scale rather than categorical (A/B/C)
- Includes creatinine — critical because renal failure in liver disease (hepatorenal syndrome) is a major mortality driver
- Used worldwide for transplant allocation
The equation above is the original MELD formula shown by the lecture, not a formula to calculate by hand for contemporary allocation. The slide next shows MELD-Na, which added sodium because hyponatraemia independently predicts mortality. Hong Kong Hospital Authority material confirms MELD/PELD-based prioritisation but the exact live allocation calculation must be checked with the transplant programme. In the United States, OPTN replaced MELD-Na with MELD 3.0 in July 2023; MELD 3.0 adds albumin and sex and updates the coefficients. [15,16]
Poor Prognostic Factors for ALF — Non-Paracetamol (King's Criteria): [1]
Irrespective of grade of encephalopathy:
- PT > 100 sec
OR 3 of the following:
- Age < 10 or > 40
- Duration of jaundice before encephalopathy > 7 days
- PT > 50 sec
- Bilirubin > 300 µmol/L
- Non-A Non-B, halothane, or idiosyncratic drug reaction
For Paracetamol Poisoning: [1]
- Arterial pH < 7.30 after adequate fluid resuscitation
OR
- all three: INR > 6.5 (approximately PT > 100 sec), creatinine > 300 µmol/L, and Grade III–IV encephalopathy
Why pH < 7.3 matters: persistent acidaemia after resuscitation reflects severe systemic and hepatic metabolic failure. Lactate measured after resuscitation is also used by specialist centres as an additional dynamic prognostic marker.
King's College Criteria have high specificity but imperfect sensitivity: meeting them supports urgent listing; not meeting them does not make observation outside a transplant centre safe. Aetiology, coma grade, lactate, vasopressor requirement, renal failure and serial trajectory must be reassessed with the transplant team. [10,11]
High Yield
King's Criteria determine who needs emergency liver transplantation. Know both the paracetamol and non-paracetamol arms. The 2024 MCQ Q55 [6] tested indications for liver transplant — the correct answer was the patient with HBV developing bleeding tendency and HE after 2 weeks of jaundice (this is ACLF meeting transplant criteria).
Depends on 6 factors: [1]
- Cerebral: HE
- Respiration: SaO₂ / FiO₂
- Circulation: Need for vasopressor
- Liver: Bilirubin level
- Coagulation: INR level
- Kidney: Creatinine level
MELD score still useful. [1]
This resembles the CLIF-C Organ Failure framework — an organ-failure assessment adapted for cirrhosis. Do not confuse the six organ domains with the complete CLIF-C ACLF prognostic score, which additionally incorporates age and white-cell count. The number and severity of organ failures drive short-term mortality. [12,13]
6. Complications of Liver Failure
Associated Complications of Liver Failure: [1]
- Infections
- Variceal bleeding
- Ascites / Spontaneous bacterial peritonitis
- Hepatorenal syndrome
- Hepatic encephalopathy
- (Coagulopathy)
Reticuloendothelial dysfunction and reduced opsonization [1] Very common (especially respiratory/urinary) Bacteraemia up to 25% in fulminant hepatic failure Staph, strep and GNR most common The slide recommends broad-spectrum antibiotic prophylaxis Risk of fungal infection — especially Candida [1]
Why liver failure patients are immunocompromised:
- The liver contains Kupffer cells (resident macrophages) which form part of the reticuloendothelial system → they clear bacteria from portal blood (especially gut-derived organisms). In liver failure, this function is impaired.
- Complement and opsonin production is reduced → bacteria are not tagged for destruction effectively
- Gut bacterial translocation is increased (disrupted gut barrier in portal hypertension)
Current correction: surveillance, not automatic prophylaxis
Routine prophylactic antibacterial or antifungal therapy has not improved bloodstream-infection rates or short-term survival in adult ALF and is not recommended by current ACG guidance. Obtain admission and serial cultures/clinical surveillance, then start prompt empiric treatment when infection, SIRS or unexplained clinical deterioration is suspected; tailor therapy to local resistance patterns. Fungal investigation/treatment is risk- and evidence-driven, particularly during prolonged multiorgan support. [10,11]
The lecture-era slide gives platelet triggers of < 50 × 10⁹/L for bleeding/procedures and < 20 × 10⁹/L prophylactically. [1]
Prolongation of PT and INR: [1]
- PT/INR important prognostic indicators
- FFP only if active bleeding/invasive procedure
Why NOT to correct INR prophylactically: In liver failure, both procoagulant and anticoagulant factors change. INR measures only selected procoagulant pathways, so it is a prognostic/synthetic marker but does not reliably predict bleeding. Plasma can cause volume overload, worsen portal pressure and obscure the trajectory of a key prognostic value.
Current practical interpretation: [10,17]
- Do not transfuse plasma merely to reach a target INR; no evidence-based target INR exists in cirrhosis.
- For active major bleeding, use local haemostasis and a goal-directed transfusion strategy; correct fibrinogen and platelets when clinically indicated, ideally guided by the bleeding site/procedure and specialist/viscoelastic assessment.
- Procedure thresholds are procedure- and guideline-specific. For high-risk procedures, some societies use platelets > 30 × 10⁹/L and others > 50 × 10⁹/L; AASLD recommends an individualised approach rather than a universal trigger.
- ALF and cirrhosis are not interchangeable haemostatic states. In ALF, avoid routine factor replacement unless there is clinically significant bleeding or a high-risk invasive procedure.
7. Hepatic Encephalopathy (HE) — The Core Topic
This is the heart of the lecture and the reason for the "incoherent" in the title.
Pathogenesis: [1]
(I) ↑Arterial ammonia:
- ↓Ability of liver to detoxify NH₃ to urea
- ↑Cerebral metabolic rate and permeability to NH₃
- ↑NH₃ → astrocyte damage
(II) ↑Proinflammatory state → ↑Blood-brain barrier permeability
- ↑Cerebral cytokines (e.g., TNF, IL-1β) leads to HE
Others: ↑Cerebral lactate, manganese accumulation in basal ganglia, GABA receptor upregulation [1]
Explanation from first principles:
-
Ammonia source: Gut bacteria (urease-producing organisms like E. coli) break down urea and amino acids → produce ammonia. Protein breakdown also generates ammonia. Normally, the liver converts ammonia to urea via the urea cycle.
-
Failed detoxification: When the liver fails, ammonia accumulates in the blood (hyperammonaemia).
-
Brain effect: Ammonia crosses the blood-brain barrier. In astrocytes, it is converted to glutamine by glutamine synthetase. Glutamine is osmotically active → astrocyte swelling → cerebral oedema (especially in ALF). In chronic HE, low-grade swelling causes functional impairment without overt oedema.
-
Inflammation amplifies: Systemic inflammation (e.g., from infections) increases BBB permeability and enhances the neurotoxic effect of ammonia. This is why sepsis is one of the most important precipitants of HE.
-
GABA upregulation: Endogenous benzodiazepine-like substances accumulate → enhanced GABAergic inhibitory neurotransmission → sedation, coma.
HE underlying mechanism diagram — what the image is teaching [1]:
The two arms synergise: ammonia-related astrocyte/metabolic stress makes the brain vulnerable, while systemic inflammation and cytokine signalling amplify neuroinflammation. This explains why the same ammonia value can accompany different clinical grades and why sepsis can abruptly worsen HE.
This is one of the most commonly examined areas. The lecture divides precipitants into two mechanisms:
Mechanism 1: ↑Nitrogen products
↑N₂ products through: [1]
- Dietary nitrogen load (lecture-era wording; do not infer routine protein restriction)
- Sepsis (catabolism → protein breakdown → ammonia)
- GI bleed (blood = high-protein load in gut → bacterial digestion → ammonia)
- Renal failure (↓renal ammonia excretion)
- Constipation (↑time for bacterial ammonia production in gut)
Mechanism 2: ↓Vascular volume → ↓O₂ delivery to liver
↓Vascular volume → ↓O₂ to liver, e.g.: [1]
- GI bleed
- Overdiuresis
- Excess paracentesis with inadequate albumin replacement
- Diarrhoea and vomiting
Other precipitants:
Sedatives [1] Electrolyte imbalance, especially ↓K [1] Acid-base imbalance [1] Artificial portal-systemic shunts (TIPS, surgery) [1]
Why hypokalaemia precipitates HE: Hypokalaemia causes intracellular alkalosis → alkalosis shifts the NH₄⁺/NH₃ equilibrium toward NH₃ (the unionized, lipid-soluble form that crosses the BBB). Also, hypokalaemia stimulates renal ammoniagenesis.
Why TIPS precipitates HE: TIPS (transjugular intrahepatic portosystemic shunt) creates a portal-systemic bypass → more ammonia-rich portal blood reaches the systemic circulation and brain. Previous or recurrent overt HE increases post-TIPS risk and requires careful selection; it is not accurately described as an automatic contraindication in every patient.
Exam-safe precipitant checklist
For a cirrhotic patient with new confusion, actively search for infection/SBP, GI bleeding, constipation, dehydration/over-diuresis, AKI, hypokalaemia or alkalosis, sedatives/opioids, non-adherence to lactulose, and a recent TIPS or other large portosystemic shunt. A normal habitual protein intake is not itself an indication to restrict protein.
The lecture next lists causes of fulminant acute liver failure, where HE arises from the primary hepatic insult. Its slide title also mentions ACLF, but ACLF still demands an active search for superimposed precipitants such as infection, GI bleeding, alcohol-associated hepatitis or HBV reactivation. [1,12]
Fulminant (Acute / ACLF): [1]
- Viral hepatitis
- Drugs (paracetamol, halothane, INAH)
- Metabolic (pregnancy, Reye syndrome, Wilson's disease)
- CVS (shock, heat stroke)
- Herbal medicines and health food products
| Grade | Mental state | Slide-derived bedside clues |
|---|---|---|
| Minimal/covert | Clinically normal examination but abnormal validated psychometric/neurophysiological testing | Impaired attention, reaction time or visuomotor performance |
| 1 | Trivial lack of awareness, shortened attention, sleep–wake inversion, anxiety/euphoria or irritability | Impaired handwriting or constructional apraxia may be an early clue |
| 2 | Lethargy/apathy, disorientation to time, obvious personality change or inappropriate behaviour | Asterixis, dysarthria, slowed responses |
| 3 | Somnolence to semi-stupor but responsive to stimuli, marked confusion and gross disorientation | Hyperreflexia/rigidity may appear; asterixis may become difficult to elicit |
| 4 | Coma, unresponsive to pain | Decerebrate responses may occur in severe disease |
The slide also maps progressively slower EEG activity and triphasic waves to higher grades. Treat that as supportive teaching, not a diagnostic table: EEG slowing/triphasic morphology is non-specific and EEG is mainly useful when non-convulsive seizures or another encephalopathy is a concern.
Cerebral oedema is uncommon in chronic HE but frequent in ALF. [1]
Why cerebral oedema differs between ALF and chronic HE: In chronic HE, astrocytes adapt by expelling osmolytes (myo-inositol, taurine) to compensate for glutamine accumulation. In ALF, the acute ammonia surge overwhelms these compensatory mechanisms → massive astrocyte swelling → cerebral oedema → raised ICP → herniation.
Confusion in cirrhosis — Differentials: [1]
- Drug- or alcohol-related
- Withdrawal state (e.g., delirium tremens)
- Head injuries
- CNS infections
- Systemic infections
- Metabolic disturbances (e.g., glucose)
- Psychiatric
- ...and more...
Clinical Pearl
Never assume confusion in a cirrhotic patient is HE — always exclude other causes first. A cirrhotic patient who drinks alcohol could be in delirium tremens (withdrawal). A patient who fell could have a subdural haematoma (especially with coagulopathy). Hypoglycaemia is common because the liver stores glycogen.
Diagnosis of HE: [1]
- Exclude other differentials
- The slide emphasises arterial ammonia:
- Normally 40% from bacterial action, 60% directly from protein breakdown
- Not always raised; may not correlate with severity of HE
- EEG abnormalities
- Other features:
- Fetor hepaticus
- Flapping tremor (asterixis)
- Psychometric tests: constructional apraxia (drawing a five-pointed star), number connection (Reitan's) test
Why ammonia doesn't always correlate with HE grade: Ammonia is one part of a multi-hit syndrome, and sampling/handling affects the result. Plasma ammonia should be measured in a patient with liver disease and unexplained delirium/encephalopathy, but it neither establishes HE nor grades its severity. A normal value should make you question the diagnosis and actively seek another cause. [18]
Complex psychometric tests for "Minimal" HE include the Inhibitory Control Test, Critical Flicker Frequency, and smartphone Stroop-type apps. [1]
The visual examples show constructional copying (five-pointed star), the Number Connection Test (connect 1→25 in sequence), computerised inhibitory-control testing, a critical-flicker-frequency headset and a colour–word Stroop app. These probe different domains and are influenced by age, education, language, vision and motor ability; use locally validated norms rather than one universal cut-off.
Minimal HE is the subclinical form — patients appear normal but have impaired psychomotor function. It can affect driving ability and quality of life, but screening and treatment are individualised rather than based on a single gold-standard test. [18]
7.7 Management of HE
Identify precipitating factors and correct if correctable, e.g., sepsis — especially look for SBP, ↓K, withdraw sedatives. [1]
This is the most important step. HE is often triggered by a reversible insult. Look for and treat:
- Infection (do a diagnostic paracentesis for SBP!)
- GI bleeding
- Electrolyte/acid-base disturbance
- Constipation
- Sedative drugs
A. Lactulose (First-Line)
Lactulose: [1]
- Non-absorbable disaccharide
- Degraded in colon by urease-negative lactobacilli
- Mechanism of action:
- Osmotic laxative (reduces transit time → less time for ammonia production)
- ↓Colonic pH:
- Inhibit urease-producing bacteria, especially E. coli
- Trap luminal NH₃ → NH₄⁺ (ionized form can't be absorbed)
- Draws NH₃ from mucosal blood to gut
- Target: 2–3 soft stools per day
- Can give enema form (useful in obtunded patients who can't take oral)
Why the pH mechanism is brilliant: Lowering colonic pH shifts the ammonia equilibrium:
- NH₃ (gas, absorbable) ⇌ NH₄⁺ (ion, not absorbed)
- Acidic environment favours NH₄⁺ → ammonia is trapped in the gut lumen → excreted in stool
Titrate to 2–3 soft bowel movements/day, not profuse diarrhoea: over-treatment can cause dehydration, hypernatraemia/hypokalaemia and paradoxically worsen HE. Protect the airway and choose the enteral/rectal route according to consciousness and aspiration risk.
B. Rifaximin (Second-Line / Adjunctive)
Rifaximin: [1]
- Non-absorbable antibiotic
- Alteration of colonic flora (especially urease-producing bacteria)
- Combined use with lactulose effective
- Also effective in reducing recurrence of HE
- Neomycin: potential nephrotoxicity/ototoxicity, no longer recommended
The Kaplan–Meier plot on the slide is from the landmark Bass et al. NEJM 2010 trial: at 6 months, remission was maintained in about 78% with rifaximin vs 54% with placebo (hazard ratio 0.42); most participants also received lactulose. The visual therefore supports adjunctive secondary prevention, not rifaximin replacing correction of precipitants or lactulose. Current EASL guidance recommends lactulose after the first overt episode and adding rifaximin after a further episode within 6 months. [18]
C. Fecal Microbiota Transplantation (FMT)
"Time will tell..." [1] — the image cites a small phase-1 capsule trial. FMT remains investigational for HE and is not routine clinical treatment; donor-derived infection transmission and product standardisation are important safety issues.
Diet: [1]
- Avoid dietary protein restriction
- The slide quotes 40–60 g/day
- Dietitian input important
Important Paradigm Shift
Old teaching said "restrict protein in HE." This is harmful: protein restriction promotes sarcopenia, reducing the muscle mass that helps metabolise ammonia. Replace the fixed 40–60 g/day slide figure with the current weight-based target of 1.2–1.5 g/kg/day, with roughly 35–40 kcal/kg/day, small evenly distributed meals and a late-night snack. During active GI bleeding, manage the bleed and rapidly clear blood from the gut; do not create a prolonged protein-deprivation plan. [19]
Branch-Chained Amino Acids (BCAA): [1]
- Detoxify ammonia via production of glutamine
- Also function as nutritional supplement
- Mainly in protein-intolerant patients
L-Ornithine-L-Aspartate (LOLA): [1]
- Converts L-ornithine to glutamate in muscle
- Conversion uses ammonia to produce glutamine
Why these are "moderate effect only": They work by providing substrates for glutamine synthesis in muscle (an alternative site for ammonia detoxification when the liver fails). However, the glutamine produced can itself be converted back to ammonia in the kidney, limiting the net benefit.
These are alternative/add-on options for selected patients who do not respond to conventional therapy, not replacements for lactulose, precipitant control or transplant assessment. Oral BCAA can help patients unable to meet protein targets; the 2014 joint AASLD/EASL guidance specifically describes intravenous LOLA as an alternative/add-on. [19]
ALF Management: [1]
1. Supportive (standard ICU care)
2. Identify and remove/treat the insult:
- HBV → Treat HBV (tenofovir/entecavir)
- Paracetamol → N-acetylcysteine (NAC)
- Mushroom → Activated charcoal (slide shorthand; see correction below)
3. Manage complications:
- Infections
- Hepatic encephalopathy
- Increased ICP / Cerebral oedema
- Renal failure
- Metabolic complications: ↓Na, ↓glucose
4. High-volume plasma exchange*
5. Liver transplantation
Unproven/Experimental: [1]
- Liver support systems (e.g., MARS)
- N-acetylcysteine for all aetiologies
- G-CSF
- Plasmapheresis (high volume)
The slide visibly puts high-volume plasma exchange in both the main list and the “unproven/experimental” box. Read this as evidence in transition, not as two separate therapies.
Why NAC works in paracetamol overdose: NAC is a precursor of glutathione. By replenishing glutathione stores, it enables detoxification of NAPQI, the toxic metabolite of paracetamol.
In adults with established ALF, current guidance commonly starts empiric IV NAC while the cause is being clarified. It is the antidote for paracetamol toxicity and may improve transplant-free survival in selected early-stage non-paracetamol ALF; that is more current than labelling all non-paracetamol use simply “experimental.” Paediatric non-paracetamol ALF is different and should follow specialist paediatric guidance. [10,11]
Suspected amatoxin mushroom poisoning: activated charcoal is only one time-dependent component. The patient needs immediate poison-centre and transplant-centre involvement, aggressive fluid/electrolyte support, serial INR/glucose/renal/liver assessment and consideration of regionally available toxin-directed therapy. Do not let a transient symptom-free phase reassure you.
High-volume plasma exchange (HVP): an open randomised trial showed improved transplant-free survival and immune modulation, so EASL describes potential benefit when used early, particularly in patients who will not undergo transplantation. It remains a specialised adjunct/bridge and must never delay definitive transplant assessment. Artificial/bioartificial support such as MARS can improve biochemical or HE measures but has not shown a clear mortality benefit and should be confined to trials/specialist protocols. [10]
8.1 The ALF bedside priorities hidden inside the multisystem slide
- Call the transplant centre early—before King’s criteria are met—and transfer to an experienced ICU when feasible.
- Track trajectory: conscious level, pupils, glucose, lactate/pH, INR, bilirubin, ammonia, creatinine/urine output, sodium, haemodynamics and infection markers/cultures.
- Protect the brain: head up, minimise stimulation, avoid unnecessary sedatives; grade III–IV HE generally requires intubation. Treat intracranial hypertension in conjunction with neurocritical/transplant specialists.
- Support metabolism and organs: prevent hypoglycaemia, avoid hyponatraemia, provide enteral nutrition when safe, use renal replacement therapy for conventional indications and potentially severe hyperammonaemia, and avoid nephrotoxins/hepatotoxins.
- Do not mask prognosis: avoid routine plasma/platelet administration unless there is significant bleeding or a high-risk procedure.
9. Integration with Related Material
| Pattern | Predominant Elevation | Think... |
|---|---|---|
| Hepatocellular | AST, ALT ↑↑↑ | Hepatitis (viral, drug, autoimmune, ischaemic) |
| Cholestatic | ALP, GGT ↑↑↑, ± bilirubin | Obstruction (stone, tumour), PBC, PSC, drugs |
| Mixed | Both elevated | Drug reaction, infiltrative disease |
| Isolated ↑bilirubin | Bilirubin ↑, rest normal | Haemolysis, Gilbert's, Crigler-Najjar |
AST:ALT ratio clues [8]:
- AST:ALT > 2:1 → Alcoholic hepatitis
- AST:ALT ~1:1 with very high levels + ↑LDH → Ischaemic hepatitis
- ALT > AST → Viral hepatitis
Both cause prolonged PT. The parenteral vitamin K test differentiates:
- If PT corrects after IV vitamin K → cholestasis (the "factory" is fine, just lacking raw material)
- If PT does NOT correct → hepatocellular failure (the "factory" is broken)
The answer was livedoid reticularis (a vascular pattern from vasculopathy/thrombotic disorders, not CLD). The CLD stigmata are: jaundice, palmar erythema, spider angioma, Dupuytren's contracture, gynaecomastia, testicular atrophy, etc.
| Trap | Why Students Fall for It | Correct Approach |
|---|---|---|
| Blaming statins for ALF | Statins are "hepatotoxic drugs" | Lecture says "actually very rare" — look for paracetamol, herbs, viral causes first |
| Restricting protein in HE | Old teaching | Avoid routine restriction; aim about 1.2–1.5 g/kg/day with dietitian input |
| Treating acute and chronic HE identically | Both involve ammonia | Lactulose/rifaximin are for cirrhotic/portosystemic HE; ALF prioritises airway, cerebral-oedema care and transplantation |
| Correcting INR prophylactically | INR is prolonged so "must correct" | INR does not predict bleeding; use blood products for clinically significant bleeding or selected high-risk procedures |
| Diagnosing or grading HE from ammonia alone | Ammonia is central to pathogenesis | A high result is non-specific and poorly grades severity; a normal result should trigger a search for another diagnosis |
| Choosing "alcohol" as cause of ALF from a single binge | Alcohol causes chronic liver disease | A single binge rarely causes ALF; alcoholic hepatitis is usually ACLF |
| Quoting one ACLF definition as universal | The lecture gives one neat definition | Name the consortium: APASL, EASL-CLIF and AASLD definitions differ |
| Forgetting TIPS as HE precipitant | TIPS is a treatment for varices/ascites | TIPS creates a portosystemic shunt → bypasses liver → ↑ammonia to brain |
High Yield Summary
-
Classify liver failure correctly:
- ALF: acute illness, no pre-existing cirrhosis, INR ≥1.5 and encephalopathy
- ACLF: rapid deterioration on chronic liver disease with organ failure; specify the diagnostic system used
- Decompensated cirrhosis: ascites, variceal bleeding, encephalopathy or jaundice
-
Know the prognostic tools:
- Child–Pugh: bilirubin, albumin, INR, ascites and encephalopathy
- MELD-family scores: use the current locally implemented calculator, not the historical hand formula
- King's College Criteria: poor-prognosis ALF criteria; referral must occur before they are met
-
Cirrhotic HE—find and correct the precipitant first:
- Common precipitants: sepsis/SBP, GI bleeding, constipation, hypokalaemia, sedatives and TIPS
- Give lactulose to target 2–3 soft stools/day
- Add rifaximin for recurrent HE according to specialist guidance
- Do not routinely restrict protein
-
ALF management:
- ICU-level supportive care and early transplant-centre referral
- Treat the cause: N-acetylcysteine for paracetamol toxicity/empirically while clarifying adult ALF; nucleos(t)ide analogue for severe HBV
- Monitor and treat infection, hypoglycaemia, renal failure and cerebral oedema; do not routinely correct INR
Active Recall - Liver Failure & Hepatic Encephalopathy
[1] Lecture slides: GC 025. A jaundiced and incoherent patient liver failure.pdf (all pages) [2] Senior notes: Block A - Introduction to GI_Hepatology investigations (LFT, Endoscopy).pdf (pp. 8, 14) [3] Past papers: 2022 Fourth Summative MCQ.pdf (Q39, p. 15) [4] Senior notes: Block A - Jaundice after raw oysters_ acute hepatitis.pdf (p. 2) [5] Past papers: 2021 Fourth Summative SAQ.pdf (Q5, p. 6) [6] Past papers: 2024 Fourth Summative MCQ.pdf (Q11 p. 5, Q55 p. 21) [7] Senior notes: Block A - Gastrointestinal Data Interpretation.pdf (p. 6) [8] Senior notes: Ryan Ho GI.pdf (pp. 204, 206, 208) [10] EASL Clinical Practical Guidelines on the management of acute (fulminant) liver failure (2017) [11] ACG Clinical Guideline: Acute Liver Failure (2023) [12] AASLD Practice Guidance: Acute-on-chronic Liver Failure and the Management [13] AASLD: ACLF — A Tipping Point in Chronic Liver Disease (2025) [14] AASLD practice guidance on drug, herbal and dietary supplement-induced liver injury (2023) [15] Hospital Authority: Information for patients and families waiting for liver transplantation [16] OPTN: Improving Liver Allocation — MELD 3.0 FAQ [17] AASLD: Peri-Procedural Management of Bleeding Risk in Cirrhosis (2024) [18] EASL Clinical Practice Guidelines on hepatic encephalopathy (2022) [19] AASLD/EASL Practice Guideline: Hepatic Encephalopathy in Chronic Liver Disease (2014)
GC024 A Fatigued And Sleepy Patient
A clinical presentation in which persistent fatigue and excessive sleepiness suggest underlying conditions such as obstructive sleep apnea, hypothyroidism, anemia, or other systemic disorders requiring systematic evaluation.
GC026 Abdominal Distension: Ascites And Cirrhosis
Abdominal distension resulting from ascites, the pathological accumulation of fluid in the peritoneal cavity, most commonly caused by hepatic cirrhosis with portal hypertension and splanchnic vasodilation.