JH IM Board Review - Acute and Chronic Liver Disease I Flashcards
Evaluation of elevated liver tests - When to fully evaluate?
Persistently or markedly (more than 10 times normal for aminotransferases or more than 4 times normal for alkaline phosphatase [AP]) elevated liver tests should ALWAYS BE FULLY EVALUATED.
AST and ALT values can guide us how?
Greater than 1000 IU/mL ==> Indicative of ACUTE viral, toxic, or ischemic hep.
==> Alcoholic hep almost NEVER raises aminotransferases above 400 IU/mL.
Which tests are the liver function tests and what do they reflect?
- Bilirubin.
- PT.
- Albumin.
==> REFLECT SYNTHETIC CAPACITY OF THE LIVER.
ALBUMIN HALF-LIFE:
3 WEEKS.
Contrary to the popular term “LFTs” …?
Aminotransferases and AP are NOT true liver function tests.
Dx - Investigating elevated liver enzymes - 1st step:
- Look at PATTERN of elevation ==> Dictates the evaluation process and diseases to be considered.
- A careful history and a review of patient’s medications, both prescribed + OTC, are CRITICAL.
Dx - Investigating elevated liver enzymes - Elevated aminotransferases should first be evaluated by …?
Serologic and biochemical tests.
Dx - Investigating elevated liver enzymes - Elevated bilirubin OR AP should be evaluated by an …?
US of the biliary tree + Anti-mt antibody.
Dx - Investigating elevated liver enzymes - If ascites is present …?
DOPPLER studies of hepatic veins to r/o outflow obstruction of the liver.
Dx - Investigating elevated liver enzymes - When to liver Bx?
Should be considered when diagnostic confirmation in required or if serologic and biochemical tests have NOT revealed the cause of the liver enzyme abnormality.
Elevated AP + GGT or 5-nucleotidase - What to do next?
- US (w/ Doppler if ASCITES present) + AMA.
- If AMA (+) or US normal ==> LIVER Bx.
- If AMA (-) or US shows dilated ducts ==> MRCP +/- ERCP.
Elevated AST and ALT - What to do next?
- Viral serologies, ANA, SMA, Iron studies, ceruloplasmin, AAT.
- Bx if above not helpful or to stage disease.
Summary of common liver disorders - Autoimmune hep:
- Elevated AST, ALT.
- Dx ==> ANA, SMA, Igs.
- Give prednisone + aza, transplant.
Summary of common liver disorders - PBC:
- Elevated AP.
- AMA.
- UDCA, transplant.
Summary of common liver disorders - PSC:
- Elevated AP.
- ERCP, MRCP, pANCA.
- Stenting of strictures, transplant.
Acute liver failure (ALF) is defined as …?
An onset of coagulopathy (ie INR >1.5) and encephalopathy within 26 WEEKS of disease presentation + WITHOUT Hx of liver disease.
==> Jaundice is often present as well.
MCC of ALF in the USA and Worldwide?
USA ==> Acetaminophen (35-40%).
Worldwide ==> Viral hep.
No specific cause of ALF is identified in approx. …% of cases.
20%.
ALF presentation - Pts may present with encephalopathy, the severity of which is related to …?
THE PRESENCE OF CEREBRAL EDEMA.
==> Cerebral edema can result in BRAINSTEM HERNIATION ==> LEADING CAUSE OF DEATH IN ALF.
ALF presentation - Patients who present with jaundice and then develop encephalopathy after several days have …?
WORSE PROGNOSIS.
ALF Presentation - Other important key points:
- Often complicated by SEPSIS, MULTI-ORGAN FAILURE (renal failure, pancreatitis), GI BLEEDING, COAGULOPATHY ==> Spontaneous hemorrhage.
- Widespread hepatocyte necrosis leads to loss of glycogen stores and impaired gluconeogenesis, causing HYPOGLYCEMIA.
ALF - Prognosis can be made using which criteria?
- King’s college criteria.
2. Clichy criteria.
King’s college criteria - Indicators of poor prognosis in ALF - Acetaminophen toxicity:
Arterial pH <7.3 after adequate fluid resuscitation OR all of the following within a 24h period:
- PT >100 (INR >6.5).
- Serum Cr >3.4mg/dL.
- Grade 3 to 4 HE.
King’s college criteria - Indicators of poor prognosis in ALF - NON-acetaminophen causes of ALF:
PT >100sec (INR >6.5) and HE (irrespective of grade). OR ANY 3 of the following:
- Wilson, idiosyncratic drug reaction, seronegative, or indeterminate hepatitis.
- Jaundice >7days before HE.
- Age <10 OR >40.
- PT >50 (INR >3.5).
- Bilirubin >17mg/dL.
ALF - Tx - Monitor which parameters?
- PT.
- pH.
- Glucose.
- Liver enzymes.
- Cultures.
- Fluid and electrolytes balance + CVP.
ALF - Tx - What to give?
- Enteral feeding, dextrose infusion, thiamine.
- PPI or H2 antagonists.
- N-acetylcysteine for ALL causes.
ALF - Tx - Mechanical ventilation?
To protect airways in pts with delirium.
ALF - Tx - Other important actions to take?
- Elevate head of bed.
- Hyperventilate initially.
- Induce hypothermia.
- Administer mannitol if serum osmolarity is less than 320 mOsm to keep ICP low; avoid procedures that may elevate the ICP.
- ICP monitor, when available, should be used to monitor perfusion pressures and ICP.
- Continuous venovenous hemofiltration for renal failure.
ALF - Tx - Clotting factors:
Incl. recombinant VII ==> ONLY FOR ACTIVE BLEEDING or before invasive procedures.
ALF - Tx - Disease-specific Tx?
- Penicillin G and silibinin for Amanita poisoning.
- Acyclovir for herpes hep.
==> There is some evidence that supports empiric use of acyclovir in idiopathic cases.
ALF - Tx - Transplantation:
Early transfer to liver transplantation center results in improved survival.
Drug-induced liver injury (DILI):
- MCC of ALF (>50%) in the USA.
- 6% of all adverse reactions involve the liver.
- DILI is the MC REASON for postmarketing withdrawal of medications.
- Reactions can be dose-dependent OR idiosyncratic.
DILI - Symptoms:
Range from ASYMPTOMATIC to nonspecific complaints, such as fatigue, nausea, vomiting, and/or mild RUQ pain.
DILI - Can follow several patterns of injury:
- Hepatitis.
- Cholestasis.
- Mixed cholestatic hep.
- Progressive bile duct injury ==> VANISHING BILE DUCT SYNDROME.
==> Injury pattern can give clue to offending agent.
Hepatic injury caused by various medications - Nonspecific or viral-like hep?
- Aspirin.
- Amiodarone.
- Diclofenac.
- INH.
- Methyldopa.
- Nitrofurantoin.
- Phenytoin.
- PTU.
- Sulfonamides.
Hepatic injury caused by various medications - Cholestasis:
- Carbamazepine.
- Chlorpromazine.
- Cotrimoxazole.
- Haloperidol.
- TCAs.
- Estrogens.
- 17-alpha steroids.
Hepatic injury caused by various medications - Steatosis:
- Alcohol.
- Prednisone.
- Tetracycline.
- Valproic acid.
- Amiodarone.
- Zidovudine.
Hepatic injury caused by various medications - Granulomatous hepatitis:
- Allopurinol.
- Quinidine.
- Sulfonamides.
- Sulfonylureas.
Hepatic injury caused by various medications - Veno-occlusive disease:
- Antineoplastics.
- Azathioprine.
- Pyrrolizidine alkaloids.
Hepatic injury caused by various medications - Adenomas and HCC:
Estrogens and anabolic steroids.
DILI - Other key features to keep in mind:
- Some cases can be immune-mediated, and HYPEREOSINOPHILIA is present (both in serum and on liver biopsy).
- Most biochem parameters return to normal after eliminating the offending agent.
DILI - Dx:
- Dx OF EXCLUSION: First exclude other more common causes of liver disease.
- Rechallenging with the suspected drug is NOT recommended.
==> If the liver injury is immune-mediated, 2nd exposure may be more severe than the initial episode.
Liver monitoring schedule for hepatotoxic medications - Every month?
- Azathioprine.
- All azoles (eg fluconazole).
- Protease inhibitors.
Liver monitoring schedule for hepatotoxic medications - Every month for 3 months, then every 3 months?
- Niacin.
2. Tacrine.
Liver monitoring schedule for hepatotoxic medications - Every 3 months?
- Amiodarone.
- Antiepileptics.
- Diclofenac.
- Statins.
- Herbal remedies.
- NSAIDs (other) ==> 3-6months.
Autoimmune hep (AIH) should be considered when?
Aminotransferases are elevated, the patient has negative viral serologies, and no drug injury is implicated.
2 types of AIH:
- BOTH more common in WOMEN.
2. Distinction between subtypes is NOT particularly useful with respect to management.
Type 1 AIH:
80%.
==> Peak incidence between 16-30.
==> More than 20% of pts are >60yr.
Type 2 AIH:
20%.
==> Typically presents ACUTELY IN CHILDHOOD.
AIH - Concommitant autoimmune diseases:
- Thyroiditis.
- Type I DM.
- SLE.
- Sjogren syndrome.
AIH - Dx:
- Elevated liver enzymes with negative viral hep serologies + Elevated gamma globulin (esp. IgG).
- Supported by histology of interface hep, plasma cells, portal tract inflammation.
- Autoantibodies NOT invariably present.
Serologic features of AIH variants - Type 1 (classic):
- SMA +/-.
- ANA +/-.
- Anti-F actin +/-.
- Antisoluble liver antigen/ Liver pancreas antigen +/-.
Serologic features of AIH variants - Type 2:
- Anti-liver kidney microsomal type 1 ab +.
2. Anti-liver cytosol 1 +/-.
AIH - Tx indications:
- Aminotrans 10 times normal.
- Aminotrans 5 times normal + 2 times up gamma globulin.
- Significant inflammation +/- necrosis on liver biopsy.
==> Many clinicians treat AIH before the aminotrans reach this degree of elevation.
AIH - Initial Tx:
Prednisone +/- aza for at least 18 to 36 months (majority of pts require lifelong Tx).
AIH - Tx for pts not responsive to standard regimen:
May require more potent immunosuppressives ==> Mycophenolate mofetil, cyclosporine, or tacrolimus.
AIH - After cessation of Tx …?
80% of pts in remission, eventually RELAPSE.
==> 50% within 6 months.
AIH - Liver tranplantation for …?
Decompensated cirrhosis.
AIH - After transplantation?
30% recurrence rate, with an average time to recurrence of 5 years.
PBC - Disease of the small or large bile ducts?
SMALL bile ducts.
PBC - 1st degree relatives have how higher risk?
50-100-fold higher relative risk compared to general population.
PBC - Age?
Median = 50yrs.
Broad range ==> 20-90.
PBC - Women or men?
90% are women.
PBC - Long-term survival?
Excellent in those responding to treatment in the 1st year of Tx (70% survival after 20years).
PBC - How is response to Tx measured?
By fall in AP to within 1.67x upper limit of normal.
PBC - Elevated total cholesterol?
UNCLEAR effect on CV risk.
==> Mostly HDL. Classic dogma is no increased risk, but this has recently been challenged.
PBC - Dx:
95% HAVE AMA.
==> Less than 1% of healthy population has AMA.
==> ANA also in most cases.
PBC - Tx:
UDCA 13-15mg/kg/day.
- Improves transplant-free survival.
- Improves liver chemistries.
- Slows histological progression.
UDCA - Exact mechanism is unclear:
Possibly:
- Incr. canalicular excretion of toxic bile acids.
- Inhibits intestinal bile acid reabsorption.
- Scavenges ROS.
Should be UDCA stopped at some time?
NEVER. Continued indefinitely.
PBC - What to give for pruritus?
Bile acid sequestrants (cholestyramine/colestipol) for pruritus.
==> 2nd line ==> Rifampin, opioid antagonists, SSRIs.
PBC - Transplantation:
Should be considered once cirrhosis and jaundice develop.
==> 5yr post-transplant survival is 80% (among the highest for all liver diseases.
==> Recurrence rate POST-transplantation is 20-25%.
PSC is a disease of …?
MEDIUM and LARGE bile ducts.
PSC - Median age:
40.
PSC - Most cases (80%) are associated with …?
IBD (particularly UC).
PSC - What percentage of pts with UC have PSC?
2.5%-7.5%.
UC + PSC and CRC?
INCREASED RISK OF COLON CANCER IN PTS WITH UC AND PSC.
What percentage of PSC pts have Crohn?
10-15%.
PSC and cholangiocarcinoma?
10y cumulative incidence is 7-9%.
PSC - Median survival?
9.5-12 YEARS from diagnosis to death or liver transplantation.
PSC - Small or large duct PSC has better prognosis?
SMALL.
PSC - Diagnosis:
Made by ERCP and MRCP ==> demonstrates strictures or beading of the intrahepatic or extrahepatic bile ducts.
PSC - Gold standard for Dx:
ERCP. (But invasive)
PSC - Dx - MRCP:
Sens ==> 80% or more.
Spec ==> 87% or more.
PSC - Role of liver Bx in Dx:
Classically shows periductal concentric fibrosis (“onion skin”) but is often nondiagnostic, especially in early disease.
- Not essential for the Dx of PSC.
- Can be helpful in assessing possible overlap syndromes and liver fibrosis.
PSC - Tx - UDCA:
- Low dose (13-15mg/kg/day) may improve biochem tests but does NOT alter symptoms, progression to cirrhosis, or survival.
- Some experts advocate for the use of low-dose UDCA if there is a reduction in AP after 6 to 12 months of use.
- High-dose (28-30mg/kg/day) UDCA may be associated with increased serious adverse events and is NOT recommended.
PSC - Screening for:
- IF CONCOMMITANT COLITIS ==> Annual screening for CRC.
2. ANNUAL screening for gallbladder mass lesions and cholangiocarcinoma with serum CA 19-9 and MRI/MRC.
PSC - Liver transplantation:
Should be offered to those with advanced liver disease or repeated bouts of cholangitis.
PSC - Recurrence after transplant:
20-25% of pts 5-10 yr after transplantation.
Alcoholic liver disease (ALD) - How much drink?
> 60g/day ==>HEAVY drinkers.
==> 10-35% of heavy drinkers develop ALD.
Cirrhosis develops in how many heavy drinkers?
8-20%.
ALD - Variables contributing to higher likelihood of ALD:
- Incr. quantity of ingested alcohol.
- Malnutrition.
- Female gender.
- Concommitant HCV.
Alcoholic cirrhosis - Prognosis:
WORSE than other causes of cirrhosis.
==> HRS is a frequent cause of death.
Patient with ALD may have CO-EXISTING:
- CARDIOMYOPATHY.
- Pancreatic insufficiency.
- +/- neurotoxicity.
ALD - Serum Igs?
IgA is often ELEVATED.
ALD - Role of liver Bx:
Can be used to stage fibrosis + exclude other forms of liver disease.
ALD - Histopathology:
Varies depending on the nature of injury:
- Macrovesicular steatosis.
- Lobular inflammation.
- Ballooning degeneration (in alcoholic hepatitis).
- Parenchymal necrosis (in alcoholic hepatitis).
- Periportal fibrosis, or cirrhosis.
- Mallory bodies are a classic finding on Bx, but are NOT specific for ALD.
ALD - Tx - Most critical component of Tx:
ABSTINENCE.
ALD - Tx - How to reduce alc craving and consumption?
BACLOFEN given orally 5mg 3 times a day for 3 days followed by 10mg 3 times a day can reduce alcohol craving and consumption.
ALD - Tx - Reversal of portal HTN?
Possible after prolonged abstinence.
ALD - Tx - Nutrition?
IMPORTANT.
==> Nutritional intervention may be at least as efficacious as corticosteroid therapy in the Tx of acute alcoholic hep.
ALD - Tx - Steroids:
PREDNISOLONE 40mg/day for 4 weeks +/- taper over 2 to 4 weeks may offer MODEST benefit in improving short-term survival in acute alcoholic hep.
The discriminant function (DF)= …?
4.6 x [PT - control (in seconds)] + Serum bilirubin (in mg per deciliter) determines the severity of disease.
DF scores of …?
32 or GREATER predict 30-50% mortality at 1 month.
==> This signals the need to consider medical therapy.
Long-term survival benefits of corticosteroids in acute alcoholic hep have …?
NOT BEEN SHOWN.
ALD - Tx - Role of pentoxifylline:
400mg 3times daily for 4 weeks may improve short-term survival in acute alcoholic hep by decreasing the risk of HRS.
ALD - Tx - When to consider pentoxifylline?
When DF score 32 or greater if steroids are CONTRAINDICATED (eg active infection).
Pentoxifylline is …?
A PDE inhibitor ==> ALSO reduces the production of inflammatory cytokines such as TNF-alpha, IL-5, 10, 12.