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