JH IM Board Review - Acute and Chronic Liver Disease II Flashcards
MC liver disorder causing elevated liver enzymes in the USA?
NAFLD.
NAFLD - Prevalence:
40%, depending on definition used and population studied.
NAFLD - Epidemiology and race:
1/3 of cases of chronic liver disease in the primary care setting.
==> HISPANICS HIGH, AFRICAN AMERICANS LOW.
NAFLD - Leading cause of death:
Cardiovascular disease.
How many pts with NASH eventually progress to cirrhosis?
15-20%.
MAIN risk factor for NAFLD:
Metabolic syndrome ==> Mainly, OBESITY + DM.
==> Insulin resistance is a hallmark.
NAFLD - AST and ALT:
Usually AST/ALT <1, UNLESS ADVANCED FIBROSIS OR CIRRHOSIS ==> Then AST/ALT >1.
NAFLD - Hepatomegaly caused by …?
Steatosis.
NAFLD - How to Dx:
LIVER BIOPSY = GOLD STANDARD.
==> Reveals either steatosis or steatonecrosis +/- fibrosis.
==> In advanced stages, histology loses characteristic fatty infiltration and may be called “cryptogenic” cirrhosis.
NALFD - Tx:
- Weight loss, strict glucose control, Tx of HTN, and lipid management are recommended.
- Vitamin E (800 IU/day) ==> Improves liver histology in biopsy-proven NASH. Unknown effects in pts with DM or cirrhosis.
NAFLD - Insulin sensitizers and lipid-lowering agents?
NOT CONCLUSIVELY SHOWN BENEFIT.
NAFLD - Liver transplantation:
Prognosis is worse in:
- Pts aged 60 or older.
- BMI 30 or greater.
- DM.
==> Recurrence of NAFLD and NASH after transplantation is well-described.
Hereditary hemochromatosis (HH) - Genetics:
- C282Y homozygotes ==> 85-90%.
- H63D homozygotes.
- C282Y/H63D compound heterozygotes.
==> Numerous other mutations eg S65C, G93R.
HH - Pathogenesis:
Incr. intestinal iron ABSORPTION:
==> Possibly caused by decr. production of the hepatic hormone HEPCIDIN, resulting in hepatic accumulation of iron.
HH - NON-HFE-related HH include mutations of:
- Hemojuvelin (HJV) gene.
- Hepcidin (HAMP) gene.
- Transferrin receptor 2 (TfR2) gene.
==> AFRICAN IRON OVERLOAD (Bantu siderosis) is a non-HFE-related HH that is worsened by dietary iron loading.
HH more common in men or women?
10X more common in men.
HH - Hepatomegaly when?
EARLY in the disease.
HH - HCC risk?
SIGNIFICANT once cirrhosis develops.
==> 5%/y.
HH - Dx - Which clues should prompt HFE mutation analysis?
- Transferrin saturation >45%.
- Elevated FERRITIN in high-risk groups.
==> Gene analysis to detect C282Y or H63D mutations.
HH - Dx - What is the next step if compound heterozygote (C282Y/H63D), C282Y heterozygote, or non-C282Y is found?
Need to r/o CONCOMITANT liver or hematologic conditions that may lead to 2o iron overload.
- LIVER ==> HCV, HBV, ALD, NAFLD.
- HEMATOLOGIC ==> Thal major, frequent blood transfusions, chronic hemodialysis.
HH - Dx - Liver Bx:
When:
- Ferritin >1000μg/L.
- Elevated liver enzymes.
==> To stage degree of fibrosis or cirrhosis, or when not C282Y homozygote to r/o other liver diseases.
HH - Dx - Screen 1st-degree members:
Either via serum transferrin saturation and ferritin.
==> Or by genetic testing.
HH - Tx - Phlebotomy:
1 unit WEEKLY or BIWEEKLY (as tolerated) until goal serum ferritin of 50 to 100μg/L, followed by maintenance phlebotomy at intervals.
HH - Phlebotomy can improve:
- Cardiac function.
- Diabetes.
- Skin hyperpigmentation.
HH - Phlebotomy CANNOT improve:
- Arthropathy.
- Established cirrhosis.
- Testicular atrophy.
- Cardiomyopathy.
HH - Tx - Iron chelation (deferoxamine):
Reasonable alternative when phlebotomy IS RESTRICTED BY ANEMIA.
==> It is also the 1st line therapy for iron overload because of ineffective erythropoiesis.
HH - Tx - What to avoid?
VITAMIN C.
AAT Def. - Lung and liver disease?
- ABSOLUTE AAT deficiency leads to LUNG disease ALONE.
2. RELATIVE AAT deficiency leads to LIVER +/- LUNG disease.
AAT def. - Lung disease results from …?
An imbalance between destructive neutrophil elastase + protective AAT in the lung.
AAT def. - Liver injury results from …?
Intrahepatocytic AAT accumulation within the RER.
MC GENETIC cause of PEDIATRIC LIVER DISEASE:
AAT deficiency.
MC genetic cause of COPD:
AAT def.
AAT def. - Clinical presentation as early as?
4-8 weeks.
- Persistent jaundice.
- Elevated aminotransferases.
- Hepatomegaly.
AAT def. - Portal HTN may develop in …?
Late childhood or early adolescence.
AAT def. may rarely be associated with:
- Necrotizing panniculitis.
2. WEGENER.
AAT def. - Dx - When to consider screening?
In adults with chronic idiopathic hepatitis OR cryptogenic cirrhosis.
AAT def. - Dx - How to screen first?
Using SERUM AAT levels.
AAT def. - Dx - When to obtain the phenotype?
Phenotype analysis if AAT level is below normal.
==> ZZ phenotype associated with advanced liver disease.
AAT def. - Histopathology:
PAS(+) + Diastase-resistant globules in hepatocytic ER.
AAT def. - Tx - Under investigation?
IV infusions of AAT derived from pooled plasma or obtained by recombinant DNA methods.
==> Under investigation for LUNG disease.
==> NOT successful for LIVER disease.
AAT def. - Tx - Liver transplantation?
The ONLY VIABLE THERAPY for the liver disease component ==> CURATIVE.
==> 5y post-transplant survival of 80-85% in adults.
Wilson - ATP7B mutation:
==> Decr. biliary EXCRETION of hepatocellular copper.
==> Cu accumulation in the liver + brain + cornea + kidneys with subsequent injury thought to caused by oxidative stress.
ATP7B mutation also prevents integration …?
Of copper into ceruloplasmin (ie apoceruloplasmin).
==> Shortens ceruloplasmin’s half-life ==> Causing lower blood concentration.
Wilson - Prevalence:
30/ million.
Wilson disease - Acute liver failure can present with …?
- COOMBS-NEGATIVE hemolytic anemia.
2. Acute renal failure.