investigations

Last reviewed 01/2018

The laboratory results show:

  • low serum calcium
  • increased plasma phosphate - low in hypocalcaemia due to intestinal malabsorption or vitamin D deficiency
  • normal alkaline phosphatase - raised in hypocalcaemia due to chronic renal failure
  • skull radiology may reveal basal ganglia calcification
  • high PTH concentrations
  • in type I pseudohypoparathyroidism, urinary cAMP fails to rise following administration of PTH
  • in type II pseudohypoparathyroidism, urinary cAMP rises normally following PTH administration