Comparison of cytological and histological examinations in different locations of the equine uterus—an in vitro study

Effects of cycle stage and sampling procedure on interpretation of endometrial cytology in mares

“…However, interpreting these results we should remember that no diagnostic test is fully accurate. For example, some observations indicate that one biopsy sample is not fully representative of the whole uterus (Fiala et al, 2010), but in contrast to these observations Overbeck et al (2013) found no significant differences in PMN numbers in biopsy material collected post-mortem from different locations of the equine uterus. Additionally, Nielsen et al (2012) showed a strong correlation between the presence of PMNs in endometrial tissue determined by histology and pregnancy results on day 70, but there was no correlation between pregnancy detected on day 70 and results of cytological examination.…”

“…The Spearman rank test (r s ) was used for evaluation of correlation coefficients between the number of PMNs cells infiltrating the endometrial luminal epithelium and the stratum compactum and cytological results. Cohen's k coefficient was calculated to evaluate the agreement of PMNs (Cocchia et al, 2012;Overbeck et al, 2013). Level of significance was set at P ≤ 0.05.…”

“…The results of cytological examinations were compared the presence of infiltration by PMNs of the luminal epithelium and stratum compactum because histological examination of the endometrium is generally used as the reference standard for diagnosis of endometritis (Nielsen, 2005;LeBlanc et al, 2007;Nielsen et al, 2012;Overbeck et al, 2011Overbeck et al, , 2013Buczkowska et al, 2014). However, interpreting these results we should remember that no diagnostic test is fully accurate.…”

“…In criterion I a total of 300 cells were counted under oil immersion (1000× magnification) and the percentage of PMNs was recorded. When PMN cells represented more than 2% of all cells in the sample, it was considered positive for endometritis (Ball et al, 1988;Overbeck et al, 2011Overbeck et al, , 2013. In criterion II, the number of PMNs/HPF was determined according to Riddle et al (2007), as follows: 0-2 PMNs/HPF indicated no inflammation; 2-5 PMNs/HPF indicated moderate inflammation; and >5PMNs/HPF indicated severe inflammation.…”

“…The presence of PMNs in the endometrial luminal epithelium and the stratum compactum is considered by several authors to be the most accurate diagnosis of endometritis in the mare (Nielsen, 2005;LeBlanc et al, 2007;Overbeck et al, 2011Overbeck et al, , 2013, but from the practitioner's point of view, the best method for diagnosis of endometritis is cytological examination, because results are obtained shortly after sample collection, and this method is relatively inexpensive.…”