Congenital testicular hypoplasia

This disease is also known as seminiferous tubular hypoplasia or primary microtesticular disease or Klinefelter syndrome (Klinefelter syndrome). Described by Klinefelter, Reifenstein, and Albright in 1942, it is characterized by small testes, azoospermia, and increased gonadotropin in urine. In 1959, Jacobs and others found that the sex chromosome of patients with this disease was 47, XXY, which is one X chromosome more than normal men, so the disease is called 47, XXY syndrome. The fundamental defect is that the male has one more X chromosome, and the common karyotype is 47, XXY or 46, XY / 47, XXY.