M4U2: URINARY CASTS Flashcards
where are urinary casts formed ?
distal and collecting tubules
urinary casts have a core matrix of ? and other proteins such as ___ and ___
uromodulin or formerly known as tamm-horsfall protiein
albumin
immunoglobulin
Uromodulin is secreted by ___ and ___
renal tubular cells of
thick ascending limb LOH and by the DCT
This is referred to as the presence of casts in urine
cylinduria
The ___ and ___ produce casts with tapered ends
ascending LOH
DCT
Broad casts are formed either in ___ or ___ or in ____
pathologically dilated
atrophied tubules
collecting tubules
Casts are always renal in origin, and they are important indicators of ___
intrinsic renal disease
Disorders which casts may be present include ___ (4)
glomerular damage
tubular damage
renal inflammation
renal infection
Factors involved in cast formation
urinary stasis
increased urinary acidity
high solute concentration
presence of normal ionic or protein constituents
Tamm-Horsfall protein is excreted at a relatively constant rate and appears to increase in cases of ___ and ___
stress
excercise
Gelation of protein and the precipitation of solutes are enhanced in an alkaline or acidic environment ? and why ?
acidic
acidification and concentration of urine occur in the distal and collecting tubules, these tubules are the sited of most cast formation
Cast presence in urine is frequently accompanied by ____ but can be seen in the absence of this as wel
proteinuria
This factor of cast formation may account for the wrinkled and convoluted appearance of older casts
urinary stasis
Casts will dissolve in ___ urine and have a specific gravity of ____
alkaline and neutral
1.003 or less
