Klinefelter syndrome
Genetic condition arising due to acquiring extra ‘X’ chromosomes
Commonest type is 47XXY, but also others i.e. 48XXXY
More number of ‘X’ = severe learning disability
Differentials for syndromes of ‘Tall Men’:
– Marfan syndrome
– Klinefelter syndrome
– Fragile-X syndrome
– Kallman syndrome
– Beckwith-Wiedemann syndrome
– Sotos syndrome
Clinical features:
Neonates have
– hypotonia
– undescended testes
– microphallus
Older boys have
– tall stature
– long limbs
– small testes (<4ml)
– gynecomastia
– learning problems
– behavioural problems
– Primary gonadal failure with
– Hypogonadotrophic hypogonadism
– Infertility
Complications:
– Infertility
– Risk of breast cancer
– Osteoporesis
Management:
– Developmental support
– Learning support in school
– Testosterone replacement can
induce puberty &
prevent osteoporosis