Patients with confirmed or suspected conditions with a resistance to vitamin D or
parathyroid hormone (PTH) will be admitted for diagnosis and treatment, and inclusion in
other studies pertaining to similar conditions.
This study will provide information about problems relating to calcium in the blood, urine,
and bones. Patients in this study will undergo a general evaluation / check-up to give
researchers an idea of each person's condition or disease. Patients will receive treatment
based on their diagnosis and asked to provide specimen samples for further research studies.
Patients with confirmed or suspected states with resistance to vitamin D or parathyroid
hormone (PTH) will be admitted for diagnosis and treatment and for inclusion in other
protocols. These states include hypocalcemia, rickets, osteomalacia,
pseudohypoparathyroidism. Resistance to a factor is manifested by deficient bioeffect
despite high levels of the factor in blood. Patients will be tested with multiple indices of
mineral metabolism to establish the diagnosis and examine the spectrum of the underlying
disorder. The principal therapies will be combinations of calcium, phosphate, and a vitamin
D analog. Selected patients will have localization and surgery to remove a tumor that causes
renal wasting of phosphate. Patients will be considered for entry into other research
- INCLUSION CRITERIA:
Patients of any age or sex with vitamin D resistance, rickets, osteomalacia,
pseudohypoparathyroidism, pseudo-pseudohypoparathyroidism, or suspicion of these or
related disorders based upon the appropriateness of their problem to ongoing
Current investigations are focused primarily upon subjects with target tissue resistance
to 1,25-dihydroxyvitamin D, pseudohypoparathyroidism, and pseudo-pseudohypoparathyroidism.