Urinalysis part 2 Flashcards
what does hemoglobin bound to haptoglobulin cause?
hemolyzed plasma
where does excess unbound hemoglobin go?
urine
+/- hemoglobin casts
+/- damage to proximal tubular cells
what happens with acute syndrome of copper toxicity in sheep?
bolus of excessive amounts: feed/pastures
severe gastroenteritis and then hemolysis
what happens in chronic syndrome of copper toxicity in sheep?
days to weeks: low molybdenum/sulfur intake and/or hepatotoxic plants
precipitating stressors lead to disease
what do horses and camelids need to ingest to get red maple toxicosis?
wilted leaves of Acer rubrum
what does copper and red maple leaves cause to red blood cells?
oxidative injury
methemogloninemia
intravascular hemolysis due to oxidation
Heinz bodies due to denaturation of oxidized hemoglobin: extravascular hemolysis
what is a common cause of hemolysis in dogs?
zinc toxicity
what does zinc cause in dogs?
oxidation through inhibition of protective enzymes
possible multi-organ damage
what are some causes of intravascular hemolysis other than heavy metals and red maple?
infectious disease
immune mediated
red blood cell metabolic defects
envenomation
what is rhabdomyolysis?
muscle necrosis
what can be seen with rhabdomyolysis?
muscle enzymes elevated in serum: creatine kinase and AST
is anemia and hemolytic serum present with rhabdomyolysis?
not usually
in whom is pigment nephropathy common in?
large animals
what causes pigment nephropathy?
hemoglobin and myoglobin being broken down
nephrotoxic heme protein
what are the mechanisms of pigment nephropathy?
tubular obstruction by casts
tubular cells ingest hemoglobin
increased synthesis of vasoconstrictive molecules
_____________ can be toxic to renal tubules- cause of AKI
especially in humans and large animals
myoglobin
your patient has a positive heme (blood) reaction and red blood cells in the sediment. what is the best interpretation for these findings?
hemorrhage in the urinary tract
artifact if did cystocentesis (hit capillary)
your patient has a positive heme (blood) reaction, but there are no red blood cells in the sediment. what is the best interpretation for these findings?
skeletal muscle necrosis and myoglobinuria
intravascular hemolysis (red blood cells breaking down within blood vessels) and hemoglobinuria
where does bilirubin originate from?
destruction of old worn-out red blood cells by macrophages in the spleen
only _____________ bilirubin can cross the glomerular wall
conjugated
why can unconjugated bilirubin not cross the glomerular wall?
bound to albumin: too large
albumin already too large to cross
is bilirubin normal to have in the urine of most species?
no
in what species is some bilirubin normal in the urine? what amount?
dogs and ferrets with highly concentrated urine
trace to 1+
renal epithelium in ____________ can conjugate bilirubin
male dogs
what are some causes of bilirubinuria?
hemolysis
hepatic disease
bile duct obstruction