Microscopic Sediment – Red Blood Cells
„ Red blood cells
„
Pathological finding - cannot appear in filtrate
if nephron is intact. result of damage / injury
to glomerular membrane,
▸
or urinary tract
▸
strenuous exercise (marathon
runners)
Microscopic Sediment – Red Blood Cells
„ differentiate:
Hemoglobinuria – free hemoglobin in urine
„ Hematuria – presence of intact RBCs in urine
„
„ Can you have positive blood on dipstick &
negative microscopic for RBCs?
„ Can you have positive microscopic for
RBCs and yet negative dipstick?
Microscopic Sediment – Red Blood Cells
„
Result of bleeding along urinary tract
„ Bleeding in nephron – red cell casts formed when
the RBCs get caught in precipitating protein
„ Bleeding in lower GU tract – no protein or casts
ƒ 160x mag
Microscopic Sediment – Red Blood Cells
„ Red Blood Cells
„ Although NV = 0-2 hpf, an occasional RBC
is more significant than occasional WBC.
„ Detection
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High power magnification
Reduced light
yellow - red sheen (sometimes blue-green)
Intact disc or may be crenated
Highly retractile, smooth surface, round
In dilute or alkaline urine appear as ghost or
shadow cells
Microscopic Sediment – Red Blood Cells
„ Urine RBCs can be easily confused with:
Yeast - - generally refract light differently,
may have buds, and often are more egg
shaped
„ Bubbles or oil droplets - large variation in
size. Even more refractile / and have
‘hard’ appearing edges.
„ Confirmation – test for hemoglobin - by
dipstick, which is most sensitive to free
hemoglobin, rather than intact RBCs
„
Microscopic Sediment – Red Blood Cells
„ Red Blood Cells
„ High magnification
„ Hypertonic urine resulting in some crenated
Microscopic Sediment – Red Blood Cells
„
RBCs of various shapes & different levels of
magnification
Microscopic Sediment – Red Blood Cells
„
fresh RBCs in the urine are often due to lower urinary
tract problems
Microscopic Sediment – Red Blood Cells
„
When RBCs are subjected to osmotic pressures
from having been in the urine for longer periods of
time, they become more dismorphic
Microscopic Sediment – Red Blood Cells
„ RBC can even get small ‘blebs’ on them, making
them appear similar to budding yeast.
Microscopic Sediment – Red Blood Cells
Microscopic Sediment – Red Blood Cells
„ Must be differentiated from yeast
„ @ 160 x