w21 liver & Gastrointestinal pATHOLOGY Flashcards
What is the structures in the system
oesoophagus
liver
stomach
small intestine
large intestine
appendix
What side of the body does the liver sit on
right ; over ribs
what organ weighs over 2% of an adults body weight
liver
LO
Normal liver function
Viral Hepatitis
Cirrhosis
Appendiciti
Name 4 functions of liver
Amino acid synthesis
Carb metabolism
Fat metabolism
Protein synthesis
Carbohydrate Metabolism in the liver digests ______ food into _____
sugary food - glucose to glycogen
Glycogenesis
formation of glycogen FROM glucose
Glycogenolysis
bdown of glycogen > glucose
Gluconeogenesis
synthesis of glucose from certain aacids, lactase or glycerol
Carbohydrates
They are the prime source of energy to do work. They are hydrolyzed to their monomeric units. These are further metabolised and converted to Glucose. Glucose is used by cell so as to form Energy(ATP). They are necessary for cellular respiration in the mitochondria.
lipids
second source of energy. If sufficient glucose or carbohydrates are not present then the body will produce Acetyl Co A from the fatty acids by the process of Beta-Oxidation. Acetyl Co A enters the mitochondria and takes part in Krebs Cycle to produce 14 ATP. Fatty acids are a very high source of energy. The fatty acid which is 18 carbon long can produce 8–9 molecules of Acetyl Co-A.
Proteins and amino acids
last source of E ; hard to extract E from to form ATP
Fat metabolism by liver involves
cholesterol synthesis, production of triglycerides (fats). (used in gluconeogenesis too)
Protein synthesis by liver inv.
liver produces, albumin, coagulation factors I (fibrinogen), II (prothrombin), V, VII, IX, X and XI,
What metabolites are formed from haemoglobin bdown by liver
bilirubin & biliverdin (added to bile as pigment)
What is Hypoalbumina
fluid excess ; into interstitial compartmts = excess swelling of liver»_space;> odema
what colour is bilirubin
yellow
What is drug metabolism by the liver
bdown or modifies toxic substances (e.g., by methylation) and most medicines.
Preferably, the toxins are conjugated to avail excretion in bile or urine.
Ammonia is converted to _____ by the liver
urea
What is the composition of haemoglobin
s 2α, 2β polypeptide chains and 4 haem molecules
What is bilirubin
yellow pigment of bile from heme bdown in OLD RBCs ; travels to liver and secreted into bile by liver
What is Serum Bilirubin a test of
liver function ; shows liver ability to take up, process & secrete BRubin into bile
when reticuloendothelial system bdowns old RBCs in spleen whats the waste product
- lipid and water insoluble form BRubin
what is free/unconjugated bilirubin & why cant it be excreted
(indirect) BRubin ; lipid& H20 insoluble needs to be made h20 soluble to be excreted in urine
Albumin
carries bilirubin to liver to convert to conjugated (direct) soluble form for excretion in urine
What enzyme is necessary for bilirubin conjugation
glucuronyl transferase
What can disturb liers ability to conjugate bilirubin
lack of GCronyl transferase or presence of drugs that interfere w glucuronyl transferase
red cell destruction, heme protein catabolism & bone marrow erthyropoiesis lead to heme breakdown which produces…
bilirubin
Describe pathway of bilirubin metabolism (using image on ipad)
bilirubin ; unconj. BR + albumin to liver ; glucuronyl transferase conjugates BR in liver ; now h20 soluble is secreted through bile duct to small intestine ; some in SI some goes to circulation
need to describe bacterial deconjugation & fecal stercobilinogen
whats the difference between indirect and direct bilirubin
bilirubin that is conjugated with glucuronic acid while the indirect bilirubin is not conjugated to the liver and it attaches to the carrier protein albumin.
How can testing show find out if bilirubin is indirect or not
Conjugated bilirubin is water-soluble and reacts directly when dyes are added to the blood specimen. The non-water soluble, free bilirubin does not react to the reagents until alcohol is added to the solution. Therefore, the measurement of this type of bilirubin is indirect.
Name a few manifestations of liver disease
jaundice ; pale stool ; dark urine ; itching ; swelling of abdomen ; fatigue ; bruising ; hepatic coma
What causes jaundice in liver disease
hemolysis ; obstruction to bile duct ;
What is jaundice
Jaundice is a yellow coloration of the skin, mucus membranes, or eyes. Other features of Jaundice include, pale or clay coloured stool, dark or borown cloured urine. The yellow coloring comes from bilirubin, a byproduct of heme released from old red blood cells.
How do pale stools occur in LDisease
bile pigment secretion blocked from bile duct obstruction ; no Brubin in small intestine so no colour
Dark urine occurs cos high levels of ______ bilirubin are excreted in urine
conjugated
Common symptom of LD is itching which is from bilirubin deposits in the
skin
Explain why abdominal swelling occurs
decreased albumin in blood > decreased osmotic pressure
= fluid accumulation in tissues
loss of nutrients, minerals and vitamins causes the general symptom of
fatigue
Esy brusing and bleeding occur from liver disease as..
liver failure means clotting factors usually made to prevent bleeding by liver are not heavy enough
Failure to remove toxins by liver can lead to what manifestation of LD
hepatic coma
Failure to remove toxins by liver can lead to what manifestation of LD
hepatic coma
Failure to remove toxins by liver can lead to what manifestation of LD
hepatic coma
Hepatic coma would only occur in late stages of disease (T/F)
true
Why is ammonia levels affected by liver disease
LFailure - ammonia (toxic) cant be converted. to urea - stays in the blood circulation = toxicity symptoms
ammonia is turned into what and released by what
urea by liver ; urine
Elevated bilirubin conc in blood can be from what 4 things
either by increased prod.,
decreased conjugation,
decreased secretion by the liver, or
blockage of the bile ducts
What can cause lead to elevated levels of unconjugated/indirect bilirubin in the blood
accelerated erythrocyte hemolysis in blood, absence of glucuronyl transferase, or hepatocellular diseases such as hepatitis
what is Unconjugated hyperbilirubinemia
elevated levels of unconjugated/indirect bilirubin in the blood
Elevated levels of conjugated/direct bilirubin is caused by
obstruction of the biliary ducts, as with gallstones or hepatocellular diseases such as cirrhosis or hepatitis.
Conjugated hyperbilirubinemia is
elevated levels of conjugated bilirubin in blood
When diagnosing LD ; elevated bilirubin levels show only that
the liver is not functioning
When diagnosing LD , high ALT enzyme levels show that
the liver cells are damaged
What is the norm range of albumin
3.9 to 5.0 g/dL
Hypoalbuminea is when the albumin levels fall ___ the normal range
under
Total bilirubin: normal range: 0.1–1.2 mg/dL. It is raised in prehepatic, hepatic, and post hepatic abnormalities
- Alanine transaminase (ALT): normal range 9 to 60 IU/L, elevated when liver cells are damaged
- Aspartate transaminase (AST): normal range 10 to 40 IU/L, It is raised in acute liver damage but is also present in red blood cells, and cardiac and skeletal muscle and is therefore not specific to the liver.
- Alkaline phosphatase (ALP): normal range 30 to 120 IU/L. ALP levels in plasma will rise with large bile duct obstruction, intrahepatic cholestasis or infiltrative diseases of the liver. ALP is also present in bone and placental tissue.
- Gamma glutamyl transpeptidase (GGT): normal range 0 to 51 IU/L. It is reasonably specific to the liver and a more sensitive marker for cholestatic damage than ALP. GGT is raised in alcohol toxicity (acute and chronic).
MAKE THIS A PROPER CARD
Name the three types of jaundice
pre-hepatic
intra-hepatic
post-hepatic
Describe pre-hepatic jaundice
when a condition speeds up the breakdown of red blood cells, causes include: malaria, sickle cell anaemia, thalassaemia. The bilirubin raised in the blood is unconjugated
Describe post-hepatic jaundice
Describe intra-hepatic jaundice
Pre hepatic jaundice causes excess hemolysis leads to
bdown by phagocytic cells (MpHs) in liver ; will liberate indirect BRubin = high unconj. in circulation ; yellowing cos of liberated BR when already deposited ; (cant move in fluid cos insoluble ?)
pre hepatic jaundice is pre cos
excess brubin produce before entering liver
Intra hepatic jaundice caused by
Viral hepatitis, alcoholic hepatitis, paracetamol overdose, leptospiroses and liver cancer.
Intra hepatic occurs when
liver inflammation compresses bile duct so conj. BR cant pass to intestine – stool colourless and from circulation goes to kidney filters = dark urine
Post hepatic jaundice is caused by
gallbladder stone obstructing bile duct, pancreatic cancer, bile duct stone or cancer and pancreatitis. The bilirubin raised in the blood is conjugated
Hepatitis is
inflamm. of liver
acute hepatitis is for______ or less and chronic is more than ___
6 months ; IS clears virus or chronic when unable to
Name causes of hepatitis
Drugs: paracetamol, isoniazid, ibuprofen, halothane, antibiotics(erythromycin, tetracyclines)
Toxins: poisonous mushrooms, and industrial chemicals such as vinyl chloride
alcohol
viral infections (A, B, C, D, E)
other infections: parasites (amoebic hepatitis, schistosomiasis) bacteria(leptospirosis) and Fungus
physical damage
Excess paracetamol usage can cause Hepatitis cos it causes
severe necrosis of liver
Hep A characteristics
Non enveloped; + strain RNA virus ; aka Picronavirus w 4 viral polypeptides (VPs)
what is a + strain RNA virus
non enveloped so RNA can directly bind ribosomes to prod. virus
FROM SLIDE CONT. HEP A B c LEFT
what is the incubation time for Hep A
15-50 days range ; average 30 days
acute inf = lifelong immunity
How can Hep A be transmitted
- fecal contam. food & h20
- contam.shellfish
Can Hep A be spread via saliva, kissing or sneezing
no
Is it 2 weeks before or after the manifestations show that a customer become contagious
before showing manifestation
After incubation HAV develop non-specific symtpoms inc. fever , malaise and anorexia.
j
What does it mean when it says Hep A infections inc. H epAV are anicteric and remain undetected
without jaundicce
Does Hep A prod. a chronic course of infection
no
Describe the general epidemiology of HAV
high in china, africa, greenland & south americe (need immuni
Hep A course using graph slide 12
What are the preventative measures against Hepatitis A
vaccine
cell-derived virus ; 2 doses administered 1 month apart
travellers get it before 3rd world countries
Anti-HAV IgM = acute infection
Anti-HAV IgG - suggest past infection (common for >50s)
liver enzyme levels raised
stool test for virus presence
most recover and become immune
Ag = viral protein
Anti HBC = Ab prod. by human against virus
DNA virus
non-enveloped ; has partial db stranded DNA
Hep B
42nm DNA virus
non enveloped , has partial db-stranded DNA
HBsAg ; HepS antigen triggers IR , AntiHBs prod.
look at structure img slide 14
How is Hep B transmitted
direct contact w blood or bodily fluids of an infected person
not spread by food, water or casual contact
