Abstract:
This is a descriptive study, to show the effect of fixation time (after
collection) of urine specimens on subsequent staining quality and
preservation of cells were evaluated in 300 smears prepared from 50
urine samples. Three limits of fixation were applied: immediate
fixation, fixation after two hours and fixation after four hours.
Of the 50 immediately fixed urine specimens, most of stained
smears showed very good staining quality constituting 36(72%)
followed by good, excellent and poor constituting, 7(14%), 3(6%) and
1(2%), respectively. Concerning staining quality of urine cells fixed
after two hours. Of the 50 specimens, 14(28%) smears have showed
well preserved cells, 25(50%) were partially degenerated cells and the
remaining 11(22%) were containing completely degenerated cells.
After
four
hours
of
fixation,
the
majority
containing
partially
degenerated cells, representing 25(50%) followed by completed
degenerated cells and well preserved cells constituting 20 (40%) and
5(10%) correspondingly. The staining quality for immediately fixed
smears and smears fixed after 2hours was categorized as, excellent (3
and 0) very good (36 and 1), good (9 and 20) and poor (2 and 20) for
both (immediate fixation and fixation after 2 hours) respectively. These
findings indicated that the preservation of urine cells as well as their
subsequent staining quality deteriorates with time and the difference
was statistically significant in each 2hours interval after the immediate
time of collection P< 0.001. Delay in fixation of urine specimens for
cytological investigations; significantly deteriorate the preservation of
cells as well as the subsequent staining quality. Sterility of collection
container doesn’t seem to affect the preservation and quality of
staining, particularly if the preparation is instantly fixed.
