RESUMEN
Our aim was to investigate sperm nuclear chromatin condensation and its correlation with semen parameters and vitality test in infertile patients with spinal cord injury [SCI], varicocele, and idiopathic infertility. Sperm chromatin condensation was determined by aniline blue staining in 22 SCI-injured infertile men, 20 with varicocele, and 28 with idiopathic infertility. The results were compared with the semen analysis parameters and the hypo-osmotic swelling test results. Three grades of staining for sperm heads were distinguished: unstained, showing sperm maturity [G0]; partially stained [G1]; and completely stained, showing sperm immaturity [G2]. The total score was calculated as: [G0 * 0] + [G1 * 1] + [G2 * 2]. In all groups, the total staining score was higher than 75%, corresponding to a high degree of immaturity of sperm. Patients with SCI had a less sperm nuclear chromatin condensation and chromatin stability than patients with idiopathic infertility and varicocele [total scores, 98% versus 89% and 88%, respectively; P <.01]. All of the patients had normal hypo-osmotic swelling test results. Sperm counts for all patients were within the reference range. The mean percentages for normal motility and morphology of the sperm were 15.5% and 15% for patients with SCI, 43% and 15% for patients with varicocele, and 62.5% and 54% for patients with idiopathic infertility. There was no correlation between sperm nuclear chromatin condensation and semen analysis parameters. Aniline blue staining for sperm nuclear chromatin condensation is a method independent of semen analysis and demonstrates the internal structural defects of sperm. This method may have a predictive value in assessing fertility