NV Flashcards
(256 cards)
Blood supply to liver?
2/3 from Portal v.-deoxygenated, rich in nutrients; 1/3 from hepatic a. - provides O2 to liver cells
Fxns of the liver?
Metabolism (carbs, lipids, AAs), Synthesis (albumin, clotting factors, VLDL, LDL, HDL, cholesterol, glycogen), Catabolism (ammonia–>urea; hormones, detoxifies foreign cmpds/drugs/chemicals), Storage (glycogen, TGs, Fe++, Cu++, fat-sol. vits), Excretion (bile, endogenous waste), Blood reservoir, Endocrine
Enzymes involved in AA metab., present in cytosol of hepatocytes, are elevated in hepatic injury
AST, ALT (serum transaminases)
ALP
enzyme removes PO4 groups, found in liver, bone and intestines as diff. isoenzymes, in bile duct/liver cells, elevated in cholestatic disorders
Most sensitive enzyme indicator of liver disease?
GGT (gamma glutamyl transpeptidase)- enzyme inv. in glutathione metab., and drug detox
When GGT and ALP are elevated together this indicates?
Hepatobiliary disease
Get decreased serum levels of this protein in liver disease but level does NOT correlate with severity of disease?
Albumin (protein produced by liver, maintains normal oncotic pressure)
Etiologies of Acute Hepatitis ?
Viral (72%), Acetaminophen OD, response to meds (ie Cipro), excess alcohol, Autoimmune, Metabolic disorders, circulatory disorders
Clinical Manif. of Severe Acute Hepatitis
Acute encephalopathy, coagulopathy, ARF, GI bleeding, Infection/Sepsis, Resp. failure, Cardiovascular collapse
Poss. outcomes of Acute hepatitis?
May: 1) Resolve w/ supportive therapy,
2) Proceed to Acute Liver Failure,
3) Develop into Chronic Hepatitis
(liver has large regen. capacity, hepatocytes divide even during necrosis/chronic injury)
What serum measurements are markers of Biliary exretory fxn?
Bilirubin, ALP, GGT
Histo features they look for when evaluating for liver hepatitis?
Spotty/lytic necrosis, Ballooning degen., Interface hepatitis, Confluent necrosis, bridging necrosis
Acute Hepatic Failure is clinical syndrome that results from?
inadequate liver fxn due to either diminished # of hepatocytes or impaired fxn; MC due to chronic liver disease, may result from compensated chronic disease w/ sudden flare of activity (acute-on-chronic LF)
Acute Hepatic Failure (AHF) → Hyperammonemia →?
Hepatic encephalopathy (behavioral changes, rigidity, hyperreflexia, Asterixis, EEG changes)
how does AHF → Coagulopathy?
decreased production of clotting factors →bleeding diathesis and incr PTT,
hypersplenism/marrow suppression → Thrombocytopenia,
liver fails to clear activated factors from circ → DIC
Microvesicular steatosis?
multiple tiny droplets of fat that do NOT displase the nucleus- seen in acute fatty liver of pregnancy and toxic rxn to drugs (such as tetracycline, valproate)
Lab findings of AHF?
elevated serum AST, ALT, hyperammonemia, hypoalbuminemia
Hepatorenal syndrome?
Functional RF w/o intrinsic morphologic abnormalities, decr renal perfusion, systemic vasodilation →compensatory renal vasoconstriction→ decr GFR,
Renal fxn normalizes if liver fxn returns to normal
Def of Chronic Liver Disease?
Various liver diseases + abnormal tests lasting 6+ months assoc. w/ progressive fibrosis, ultimately → cirrhosis
Pathogenesis of Liver Cirrhosis?!
Stimulation of Ito/stellate cell by ROS, Gfs, IL-1 produced by damaged hepatocyte→ myofibroblast-like cell: produces smooth m. actin, GFAP →→ collagen deposited→ fibrosis →cirrhosis
Etiologies of Chronic liver disease?
NAFLD, Hep B/C, Alcoholic LD, Hereditary hemochromatosis, alpha-1 antitrypsin deficiency, Wilson’s disease, PBC/PSC, Autoimmune hepatitis
Pathophys changes in liver cirrhosis that →alterations on microvasculature architecture ?!
Loss of Sinusoidal cell fenestrations, Shunt development, High-pressure, fast-flowing vessels WITHOUT solute exchange, loss of functional integrity
Regenerative nodules?
micro (<3mm) and macro (3+ mm) from regeneration of liver cells in canals of Hering (progenitors of parenchymal and bile duct cells), seen in Cirrhosis
Morph of Cirrhosis
Bridging fibrous septa: fibrosis c/o delicate bands or broad scars surrounding multiple adjacent lobules,
Disruption of ENTIRE liver architecture by fibrous scars,
Regenerative nodules,
alterations in microvasculature