The microscopic examination is a vital part of the routine urinalysis.
It is a valuable diagnostic tool for the detection and evaluation of renal and urinary tract disorders as well as other systemic diseases. The best specimen for the routin urinalysis is the first morning specimen.
The sediment should be examined as soon as possible after collection;
But it may be refrigerated for a few hours if the examination cannot be performed immediately.
Mix the specimen and then place 10-15ml of urine into a centrifuge tube
Centrifuge at 2000rpm for 5 min.
Pour off the supernatant fluid,and resuspend the sedment in the urine draine back down from the side of the tube.
Flick the bottom of tube to mix the sediment,and place a drop of sediment on a slide.
Cover with a cover slide and examine immediately.

Note: the sediment should be viewed first low power magnification(100x). Switch to high power(400x)when necessary to delineatethe structures that are seen.
Casts can be counted under low power magnification(100x),and the average number in 10-15fields is reported(e.g1-3 hyaline cast/LPF).
Red blood cell, white blood cell,and epithelial cell are counted under high power(400x),and average number in 10-15 fields is reported (e.g 20-25/HPF).
Clinical implications for different tybe of casts:
1-RBC cast:
A/glomerulonephritis
B/ renal infarction
2-WBC cast:
A/pyelonephritis
B/lupus nephritis
3-Epithelial cell cast:
A/nephritis
B/glomerulonephritis
4-Hyaline cast:
A/malignant hypertension
B/chronic renal disease
5-Granular cast:
A/pyelonephritis
6-Waxy cast:
A/chronic renal disease