Hepatobiliary System Flashcards
characteristics of hepatitis viruses
families
HAV-RNA picornavirus HBV-DNA hepadnavirus HCV-RNA flavivirus HDV-RNA delta virus HEV- RNA hepevirus
hepatitis viruses: trasmission
HAV-fecal oral (overcrowding and poor sanitation, containated water or food, raw or steam shellfish in US)
HBV-paraenteral, sexual, maternal fetal
HCV-primary blood
HDV- paraetenteral, sexual, maternal fetal
HEV-fecal-oral, esp with waterbone epidemics
“vowels hit your bowels” do not depend on envelope so not destroyed in gut
hepatits viruses: carrier
HAV-No HBV-Yes HCV-Yes HDV-Yes HEV-No
hepatitis viruses: incubation
HAV-short (weeks) HBV- long (months) HCV-long HDV-superinfection (HDV after HBV)-short; coinfection(HDV with HBV)-long HEV-short
hepatitis viruses: HCC risk
HAV-No HBV-Yes:intergrates into host genome HCV-Yes from chronic inflammation HDV-Yes HEV-No
hepatitis viruses: notes to remember
HAV-Asymptomatic (usually), Acute, Alone (no carriers)
HBV- non
HCV- chronic, cirrhosis, carcinoma, carrier
HDV-defective virus, dependent o HBV; superinfection leads to decreased prognosis
HEV- high mortality in pregnant women, enteric, expectant, epidemic
pt with no apparent liver disease who have mild unconjugated hyperbilirubinemia provoked by classical triggers? name disease and triggers?
Glibert Syndrome
-hemolysis, fasting, physical extertion, febrile, illness, fatigue, and stress
normal total bilirubin-0.1-1.0; direct 0-0.3
Liver enzymes that test
- functionality (4)
- intactness (1-example)
- biliary tract (2, which is non-specific and which is?)
- prothrombin time, bilirubin, albumin, cholesterol
- transaminases (ie. aspartate aminotransferases)
- alkaline phosphatase (non-specific) , and gamma-glutamyl transferase
a moderately elevated alkaline phosphatase of unclear etiology should be followed up with measurement of?
gamma-glutamyl
-alkaline phosphatase can be elevated in a number of tissues.
homobox genes encode for
DNA-binding transcriptoin factors
debranching enzyme deficiency vs glucose-6-Phosphatase deficiency vs glycogen phosphorylase (liver and muscle invovlement)
Cori disease incomplete glycogen degradation. alpha 1,16-glucosidic branch points cannot be degraded- “small dextrin-like material accumulates within cytosol of hepatocytes”, no fatty liver,
- G-6-phosphatase (aka Von Gierke’s disease) hepatic steatosis, no muscle involvement
- aka McArdle’s syndrome affects muscles, exercise intolerance, muscle pain, cramping, myoglobinuria, low blood lactate after exercise and excess glycogen in muscle biopsy.
deficiency in acid maltase-action and location of enzyme, name of disease, presentation: glucose levels, other organ involvement? histo findings?
lysosomal enzyme has both alpha 1,4 and alpha 1,6 glucosidase activity. Pompe’s disease, no hypoglycemia, instead cardiomegaly and severe hypotonia. histo shows abnormal glycogen accumulation within lysosomes
location of portal vein on CT- aorta, liver, IVC
- look for celiac trunk emerging off aorta at T12/L1 level
- just medal or within right lobe of liver
- anterior to IVC
location of poly-A tail in mRNA and relation to consensus sequence
3’ end, downstream of concsensus sequenence (AAUAAA)
hepatic processing of bilirubin (3 steps ):
1) carrier-mediated uptake of bilirubin
2) conjugation with glucuronic acid by UGT (uridine diphosphate-glucuronyltransferase)
3) biliary excretion of water-soluble nontoxic bilirubin glucuronides
unconjugated vs conjugated bilirubin
- bound to albumin, water insoluble, can’t be filtered by kidney
- non bound to albumin, water soluble, can be filtered and removed by kidney
name 4 diseases that can lead to hyperbilirubinemias
- Gilbert syndrome=problem with bilirubin uptake=unconjugated bilirubinemia (mild jaundice, little clinical consequences)
- Crigler-Najjar syndrome type I=problem with bilirubin conjugation (UDP-glucoronosyltransferase)=unconjugated bilirubin (jaundice, kernicterus, early death)
- Dubin-Johnson syndrome=problem with excretion of conjugated bilirubin=conjugated bilirubinemia (black liver, benign)
- Rotor syndrome=mild conjugated hyperbiliirubinemia (no black, liver)
effect of cirrhosis on estrogen levels? testosterone levels? effect of estrogen levels on body (3)? not musty body odor because?
estrogen levels increase because of livers inability to break them down,
also results from increase sex hormone binding globulin which binds free testosterone.
leads to gynecomastia, testicular atrophy, and spider angiomata
musty body odor is due to hyperammonemia
thiamine serves as a co factor for which three key enzymes?
- transketolase (ribulose-5 phosphate to fructose-6 phosphate in HMP shunt)
- alpha-ketoglutarate dehydrogenase (alpha ketoglutarate to succinyl CoA in TCA)
- pyruvate dehydrogenase (pyruvate to Acetyl-CoA in glycolysis)
how is copper absorbed? excreted?
- absorbed in stomach in duodenum copper is used to form ceruloplasmin*
- senesecent ceruloplasmin and unabsorbed copper are secreted into bile and excreted in stool which is primary route for copper elimination (90-95%)
- other route is through renal tubular secretion (5-15%)
which one is a transcription factor? Ras or C-Jun
- c-Jun along with c-Fos bind DNA
- Ras is a proto-oncogene that codes for a membrane bound G-protein that does not bind to DNA
role of prokaryotic 16S mRNA
- found in 30S subunit.
- rRNA that binds to Shine-Dalgarno sequence upstream of start codon on bacterial mRNA. needed for initiation of protein translation
which rxn does HMP shunt provide energy for? not ADP to ATP phosphorylation because?
- creates NADPH which is an electron donor for anabolic rxns (cholesterol and fatty acid synthesis)
- ATP is not formed or used in HMP shunt
explain mechanism of liver injury in pt positive of HBsAg? not viral cytotoxic effect and hepatocyte necrosis with following secondary inflammation b/c
- CD8+ lymphocytes response to viral antigens on cell surface results in hepatocyte damage
- hep B virus has not direct cytotoxic effect
aspiration of hydatid cyst (aka?) can cause? appearance? pt pop? not septic shock b/c?
- aka echinoccocus granulosus cysts
- anaphylatic shock
- calcified cyst “eggshell calcification”
- mediterranean, middle east, southern south america, iceland, australia* and new zealand
- overwhelming bacterial infection causes septic shock
main toxicity of isoniazid
- hepatotoxic (or hepatatitis- fever, anorexia, and nausea)
- peripheral nerve damage if B6 is not also administered
side effects of all protease inhbitors
- lipodystrophy (buffalo hump-increased fat on back and abdomen and less in extremeties)
- hyperglycemia (increased insulin resistance can lead to DM)
- inhibition of p-450
why not give rifampin with protease inhibitors (HIV pt with TB?) give what instead?
b/c rifampin is P-450 activator and will decrease serum levels of rifampin (inhibitor)
-give rifiabutin instead
liver cancer associated with vinyl chloride, arsenic, or Thorotrast
hepatic angioscarcoma
-aggressive and poor prognosis
mc malignant hepatic lesion
met from another primary site
CT contract of liver with multiple nodules and bright round structure on right
- liver with met cancer
- bright structure is stomach with contrast
pathogenesis of Wilson’s disease. presentation. treatment
- too much non-ceruloplasmin -bound serum copper
- causes injury to liver, CNS, lenticular nucleus, and cornea
- penicillamine (copper chelator)
TATA box is needed for
transcription initiation
presentation of acute hepaptisis. not prolonged puritis and fatigue b/c
- fever and dark urine (increased bilirubin)
- puritis is seen in scleorising cholangitis (diffuse inflammation and fibrosis of biliary tract)
hepatocyte injury vs hepatocyte death
- ballooning degeneration, diffuse swelling
- lobular architectural disruption and confluent hepatocyte necrosis “bridging necrosis”
- both cause mononuclear inflammation in sinusoids and portal tracts
inheritance patterns of classical galatosemia vs Lesch-Nyhan syndrome
- autosomal recessive
- X-linked recessive
give examples of viruses that replicate by
-one stranded DNA-template double stranded DNA-progeny one stranded DNA
parvovirus B19
give examples of viruses with this replication pattern
double strained DNA-template double stranded DNA-progeny double stranded DNA
papovavirus, adenovirus, hepesvirus, poxvirus
give examples of viruses with this replication pattern
-double stranded DNA-template (+)RNA-progency double stranded DNA
hepadnavirus (HBV) b/c of reverse transcriptase DNA polymerase that creates an intermediate (+) RNA strand
give examples of viruses with this replication pattern
-one stranded (+) RNA-template
(-) RNA- progeny one stranded (+) RNA
poliovirus
give example of viruses with this replication pattern
-one stranded (+) RNA-template double stranded DNA- progeny one stranded (+)RNA
reovirus (HIV)
give example of viruses with this replication pattern
-one stranded (-)RNA-template (+) RNA-progeny one stranded (-) RNA
influenza, measles, rabies
newborns of all mothers with hep b are given what a birth? what is given afterwards?
- passive immunity with hep B immune globulin (HBIG)
- active immunization with recombinant HBV vaccine (once baby’s immune systems is mature)
glycogen storage disorder due to deficiency of
- glucose-6 phosphatase
- glycogen phosphorylase
- debrancher enzyme
- alpha-glucosidase aka acid maltase
- hepatosplenomegaly (enzyme in liver only not muscle), lactic acidosis. (Von Gierke’s disease)
- poor exercise tolerance, no lactic acidosis (McArdle’s disease)
- hepatosplenomegaly, muscle weakness. Cori or Forbes disease
- hepatoslemomegaly, caridomegaly, hypotonia (Pompe’s disease)
sucrose becomes
lactose becomes
maltose becomes
- fructose+glucose
- galatose+glucose
- glucose+glucose
name phases of gastrin release? what mediates them? what reduces gastrin release
- cephalic, gastric,and intestinal
- vagal and cholinergic mech. present of gastrin (causes release of histamine from ECLs) in stomach. protein in stomach (minor role)
- intestinal influences (peptitide YY)-binds to enterochromaffin-like cells (cells with histamine) to block it’s relaase
parasitic destruction of myenteric plexi in esophagus, intestines, and ureters. presentaiton?
Chagas disease (Trypanosoma cruzi) -achalasia, megacolon, and megaureter respectively