RESUMO
<p><b>OBJECTIVE</b>To explore the correlation of the testosterone level with circulated endothelial progenitor cells in patients with Klinefelter's syndrome (KS) and its clinical significance.</p><p><b>METHODS</b>This study included 36 patients affected by non-mosaic 47, XXY KS, each with one or more cardiovascular risk factors. Serum hormone levels and the content of circulated endothelial progenitor cells were determined by radioimmunology and cell culture methods, respectively, and the measurement was repeated after 6 months of testosterone replacement therapy.</p><p><b>RESULTS</b>After testosterone replacement therapy, the testosterone level was increased from (8 +/- 3) to (24 +/- 10) nmol/L, while the content of endothelial progenitor cells ([41 +/- 48] cells/ml) showed no significant rise.</p><p><b>CONCLUSION</b>There is no obvious correlation between the testosterone level and the content of endothelial progenitor cells in KS patients.</p>