Hepatology Flashcards
Roles of the liver (6)
- Macronutrient metabolism (glucose, lipid, cholesterol, amino acid and protein – Urea cycle)
- Breakdown of xenobiotic compounds
- Secretion – Bile
- Storage – Vit A, D, B12, Cu, Fe
- Haematological function - phagocytosis, hemopoiesis
- Endocrine control of growth
What is the primary epithelial cell of the liver?
Hepatocytes
What is the secondary epithelial cell of the liver?
Cholangiocytes–> biliary epithelium
Glucose metabolism definitions
Glycolysis
Glycogenesis
Glycogenolysis
Gluconeogenesis
Ina diabetic state which of these 2 processes is increased?
Glycolysis- metabolic pathway that converts glucose to pyruvic acid while releasing energy
Glycogenesis- the formation of glycogen, the primary carbohydrate stored in the liver and muscle cells of animals, from glucose.
Glycogenolysis- biochemical pathway in which glycogen breaks down into glucose-1-phosphate and glucose. The reaction takes place in the hepatocytes and the myocytes.
Gluconeogenesis and glycogenolysis
Gluconeogenesis- generation of glucose from certain non-carbohydrate carbon substrates. Maintains blood sugar between meals and is stimulated by the diabetogenic hormones (glucagon, growth hormone, epinephrine, and cortisol)
Livers role with lipids
- Uptake, synthesis, packaging and secretion of lipids + lipoproteins
- Fatty acids are extracted from cholymocrons–> which in turn are formed by digested lipids from the gut
- Lipid soluble vitamin absorption (Vitamins A, D, E, and K)
- Cholesterol Homeostasis – HMG-CoA Pathway
- Ketogenesis
Ketogenesis process
Normally body metabolises carbohydrates leading to efficient energy production. In starvation states like diabetes, liver cells break down fatty acids and ketogenic amino acids into acetone (sweet breath).
ketoacidosis presentation
- Gradual drowsiness
- Vomiting
- Dehydration in T1DM
- Ketotic breath
- Coma
- Sighing Kussmaul breathing
Diagnosis of ketoacidosis
Hyperglycaemia (>11.0 mmol/L)
Acidaemia (pH <7.3)
Ketonaemia (>3.0 mmol/L)
Where are most of the coagulation factors produced?
liver
What are the vitamin K dependant clotting factors?
2, 7, 9, 10
Name 3 proteins produced by the liver that contribute to anticoagulation
protein C&S, heparin, antithrombin
What is DIC? Disseminated intravascular coagulation
in a severe systemic illness dying cells release procoagulant agents that activate coagulation, resulting in fibrin generation that occludes small vessels.
Platelets and clotting factors are used up and result in bleeding elsewhere.
in DIC Blood tests reveal?
thrombocytopenia, increased PT/INT and APTT, and raised D-dimer and fibrin degradation products. Treat by removing cause and supportive therapies (blood, platelets, FFP, cryoprecipitate).
Causes of DIC?
- Blood transfusion reaction.
- Cancer, especially certain types of leukemia.
- Inflammation of the pancreas (pancreatitis)
- Infection in the blood, especially by bacteria or fungus.
- Liver disease.
- Pregnancy complications (such as placenta that is left behind after delivery)
- Recent surgery or anesthesia.
How does liver disease contribute to bleeding disorder?
vit k
Bile is needed to absorb the lipid vitamins (Vitamins A, D, E, and K). Vitamin K is needed to produce the 2,7,9 and 10 clotting factors
