Rare Case of 47XXY/46XX Mosaic Klinefelter Syndrome

This document discussed a rare case of 47XXY/46XX mosaic Klinefelter syndrome (KS), which is a genetic condition affecting male infertility. The case involved a 39-year-old male with symptoms such as fatigue, weight gain, and loss of libido, alongside physical characteristics like small testes, gynecomastia, and male pattern baldness. Chromosome analysis revealed a mosaic pattern with 83% of cells being 47XXY and 17% being 46XX. The study highlighted that KS mosaicism can lead to delayed diagnosis due to the variability in cell line distribution across tissues and the challenges in detecting the 46XX cell line in routine tests. The presence of a Y chromosome in the gonad was noted to determine the phenotype, and mosaic cases were found to be more androgenic and more likely to have spermatogenesis compared to non-mosaic KS.