Variant Klinefelter Syndrome With Xq Trisomy (47,X,i(X)(q10),Y): A Case Report and Review of the Literature.

Variant Klinefelter syndrome (VKS) presents with variable phenotypes, caused by the involvement of different genetic abnormalities leading to delays in confirming diagnosis and, therefore, delays in early management of this disorder. We describe a male with VKS and trisomy Xq resulting from an isochromosome X(i(Xq10)). He had characteristics of classical KS such as azoospermia, hypergonadotropic hypogonadism with elevated follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels, and bilateral atrophic testes. He achieved a normal intelligence level. However, we observed a normal stature appropriate for his height. There was no history of developmental delays or learning problems during childhood. His karyotype was found to be 47,X,i(X)(q10),Y, which indicates that extra copies of the long arm of Xq (trisomy Xq) have phenotypic expression. In conclusion, Trisomy Xq does not affect stature and neurological development and does not express classical phenotypes during early childhood. Hence, the cytogenetic screening of sex chromosomal abnormalities is important in cases of hypergonadotropic hypogonadism and testicle abnormality, which can help in appropriate genetic counseling.