Flow cytometric ploidy analysis of testicular biopsies from sperm-negative wet preparations.

BACKGROUND The use of testicular sperm in assisted reproduction depends on the availability of sperm in wet preparations. It is not always possible to recover sperm from the testis, even with previous sperm-positive histopathological findings. The purpose of this study was to evaluate the sperm-negative wet preparation search results with flow cytometric ploidy analysis and histopathological examination. METHODS Two pieces of testicular tissue were obtained from azoospermic patients to investigate the spermatogenic status of the testis, and to determine the presence of sperm through a wet preparation. The testicular tissue was shredded and then vortexed; the cellular suspension was then processed for a wet preparation sperm search, while the residual tissue was exposed to enzymatic digestion for flow cytometric ploidy analysis. RESULTS A total of 38 patients had sperm-negative wet preparation results. Of those, six (16%) were shown to have haploid cells after flow cytometric analysis. Histopathological examination showed three samples with maturation arrest at the spermatid stage, and the other three at the spermatocyte stage. CONCLUSIONS Flow cytometric ploidy analysis can be used to verify the results of a wet preparation sperm search when no sperm were detected. Flow cytometric ploidy analysis can also reveal the presence of spermatids when no sperm are available.