Klinefelter Syndrome

Synonyms

48,XXYY Syndrome

49,XXXXY Syndrome

Klinefelter Syndrome, Variants

Klinefelter Syndromes

Klinefelter Syndromes, Variants

Klinefelter's Syndrome

Klinefelters Syndrome

Syndrome, Klinefelter

Syndrome, Klinefelter's

Syndrome, Variants Klinefelter

Syndrome, XXY

Syndrome, Xxyy

Syndromes, Klinefelter

Syndromes, Variants Klinefelter

Syndromes, XXY

Syndromes, Xxyy

Trisomies, XXY

Trisomy, XXY

XXXY Male

XXXY Males

XXY Syndrome

XXY Syndromes

XXY Trisomies

XXY Trisomy

Xxyy Syndrome

Xxyy Syndromes

A form of male HYPOGONADISM, characterized by the presence of an extra X CHROMOSOME, small TESTES, seminiferous tubule dysgenesis, elevated levels of GONADOTROPINS, low serum TESTOSTERONE, underdeveloped secondary sex characteristics, and male infertility (INFERTILITY, MALE). Patients tend to have long legs and a slim, tall stature. GYNECOMASTIA is present in many of the patients. The classic form has the karyotype 47,XXY. Several karyotype variants include 48,XXYY; 48,XXXY; 49,XXXXY, and mosaic patterns ( 46,XY/47,XXY; 47,XXY/48,XXXY, etc.).