Wednesday, 22 September 2010

MRCP revision battle 18.8: Pseudohypoparathyroidism

Pseudohypoparathyroidism is an autosomal dominant condition that occurs when a person is insensitive to PTH.

Features include:
  • short metacarpals (esp 4th and 5th)
  • short stature
  • round face
  • obese
  • low IQ
  • dental hypoplasia

It can be diagnosed by a failure of cAMP to increase after injection of parathyroid hormone.  More traditionally, the clinical picture of low calcium, high PTH and normal/raised alk phos is enough.

Treatment is with alfacalcidol.

It is worth noting it is associated with slipped femoral epiphysis.

To end today's battles on an almost comic note (and the fact I find this comic is a reflection that I really should get out more) there also exists a pseudopseudohypoparathyroidism, which is essentially the morphological features of pseudohypoparathyroidism but with normal biochemistry.  Hopefully that'll make you smile if it comes up!

A few questions on yesterday's battles are now online here, otherwise see you tomorrow!