Micro UA part 2

Question 1

Casts
where are they formed?
shape?

Answer 1

formed only in the kidney nephron
loop of henely
distal tube
collecting duct

Shape represents tubule

Question 2

Structure of casts

Answer 2

parallel sides
rounded edges
some fragmented

Question 3

Composition of casts

Answer 3

tamm-horsfall (uromodulin)
glycoprotein excreted by RTE - lubrication

constant rate
makes up mucus
‘gels’
not detected by rgnt strip

Question 4

Formation of casts

Answer 4

tam-horsfall RTE protein
fibrils from network loose
futher matrix
urine comp attaches to matrix
cast detaches from RTE

Question 5

What is casts in urine called

Answer 5

cylinduria

occurs more readily if urine flow decreased
pH is acidic
increased electrolytes

Question 6

T/F forms of casts dont block the urine in the nephron

Answer 6

false

Question 7

patho vs non patho casts

Answer 7

patho: renal issue

non patho: dehydration

Question 8

Types of casts

Answer 8

elements/size/shape/time

hyaline - most common

Cellular - Rbc/wbc/rte

fatty

granular

broad - collecting duct
waxy - severe renal stasis

Question 9

Hyaline cast

Answer 9

most frequent
in loop of henely/distal/collecting

0-2 norm
low power

Noth path: excersise/dehydration/heat

Patho: acute glomer, pylnoneph, renal

Question 10

What do hyaline casts look like when they come from the henely loop?

Answer 10

wiggly tails

Question 11

Hyaline cast morphology

Answer 11

hard to see

sternheimer-malbin/phase contrast

parallel with round edges
few granules
cells will stick

Question 12

RBC casts

Answer 12

rbc embedded in matrix
not stuck on outside
free floating rbcs seen
“pos” on blood strip

Non path: rare - extreme exersice

Path: bleeding in nephron assoc w glomerulon

Question 13

If hgburia is present, what color is the rbc cast?

methgb?

Answer 13

orange/red color

methgb is brown/red

Question 14

What are hgb type casts associated with?

Answer 14

associated with aute tubular necrosis
very large amounts toxic to kidneys and result in renal failure

Question 15

WBC casts

Answer 15

wbc embedded in matrix
neutrophils
granular appearance, dont confuse w wbc clumps

Path: infections/inflamm

Question 16

Pylonephritis

Answer 16

upper uti

Question 17

Cystitis

Answer 17

lower uti doesnt produce wbc casts

Question 18

Bacteria casts

Answer 18

bacteria in cast
associated with pylonephritis

wbc and free floating bacteria present

confused w granular casts

RARE

confirm with gram stain

Question 19

RTE casts

Answer 19

very serious very rare
tubular destruction

diff from wbc casts use STAINING mononuclear structure

Question 20

Oval fat body casts

Answer 20

comp. of fat drop of oval fat body
refractile
confirm with polarized light and fat stain
Sudan III or Oil Red O

Cholesterols - maltese cross

Question 21

mixed cell

Answer 21

diff cell types

rbc/wbc: glomerul

wbc/RTE: plyonephritis

Question 22

Granular casts

Answer 22

pick up material from urine - degrade “granularity”
crystalize
rbc
wbc
CELLULAR MATERIAL FROM RTE MOST COMMON

Question 23

Granular casts start as

Answer 23

start as course and go to fine
must have urinary stasis occur for granular casts to form

Question 24

Waxy cast

Answer 24

long term urinary stasis
chronic renal failure
seen with other casts
occur from futher breakdown of gran. casts

brittle refract index
fiber
fragmented square endds
notches
dark pink

Question 25

Broad casts

Answer 25

renal failure casts
wider 2-6x than typical cast
very long term urinary stasis

can form from anytype of cast

MOST COMMON WAXY/GRANULAR

from distal tube due to dilation (wider walls)

collecting duct severe renal flow dec