Cytological artifacts masquerading interpretation

Cytological artifacts are important to learn because an error in routine laboratory practice can bring out an erroneous result.

The aim of this study was to analyze the effects of delayed fixation and morphological discrepancies created by deliberate addition of extraneous factors on the interpretation and/or diagnosis of an oral cytosmear.

A prospective study was carried out using papanicolaou and hematoxylin and eosin-stained oral smears, 6 each from 66 volunteer dental students with deliberate variation in fixation delay timings, with and without changes in temperature, undue pressure while smear making and intentional addition of contaminants. The fixation delay at room temperature was carried out at an interval of every 30 minutes, 1 day and 1 week and was continued till the end of 1 day, 1 week, and 1 month, respectively. The temperature variations included 60 to 70°C and 3 to 4°C.

Light microscopically, the effect of delayed fixation at room temperature appeared first on cytoplasm followed by nucleus within the first 2 hours and on the 4(th) day, respectively, till complete cytoplasmic degeneration on the 23(rd) day. However, delayed fixation at variable temperature brought faster degenerative changes at higher temperature than lower temperature. Effect of extraneous factors revealed some interesting facts.

In order to justify a cytosmear interpretation, a cytologist must be well acquainted with delayed fixation-induced cellular changes and microscopic appearances of common contaminants so as to implicate better prognosis and therapy.