Changes

[[Image:Renal_osteodystrophy.jpg|thumb|right|200px|"Rubber jaw" in renal osteodystrophy. Image courtesy of Biomed Archive.]]

[[Image:Renal_osteodystrophy.jpg|thumb|right|200px|"Rubber jaw" in renal osteodystrophy. Image courtesy of Biomed Archive.]]

[[Image:Renal osteodystrophy.jpg|right|thumb|200px|Renal osteodystrophy (Image sourced from Bristol Biomed Image Archive with permission)]]

[[Image:Renal osteodystrophy.jpg|right|thumb|200px|Renal osteodystrophy (Image sourced from Bristol Biomed Image Archive with permission)]]

Primary hyperparathyroidism originates within the parathyroid gland itself and can be due to glandular hyperplasia or [[Neoplasia - Pathology|neoplasia]]. It is most commonly due to a solitary benign [[Adenoma|adenoma]] of either the [[Parathyroid Glands - Anatomy & Physiology|internal or external parathyroid gland]].<ref name>Merck Veterinary Manual, '''Primary Hyperparathyroidism''', accessed online 25/07/2011 at http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/40407.htm</ref>

Hyperparathyroidism is an '''[[Endocrine System - Anatomy & Physiology|endocrine]] disease''' caused by overactivity of the [[Parathyroid Glands - Anatomy & Physiology|parathyroid gland]] and consequent '''raised body levels of [[Calcium#Parathyroid Hormone|parathyroid hormone (PTH)]]'''. It occurs in many veterinary species and can be primary or secondary.  

Secondary hyperparathyroidism can be either renal or nutritional in origin:

'''Primary hyperparathyroidism''' originates within the parathyroid gland itself and can be due to '''glandular hyperplasia or [[Neoplasia - Pathology|neoplasia]]'''. It is most commonly due to a '''solitary benign [[Adenoma|adenoma]]''' of either the [[Parathyroid Glands - Anatomy & Physiology|internal or external parathyroid gland]].<ref>Merck Veterinary Manual, '''Primary Hyperparathyroidism''', accessed online 25/07/2011 at http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/40407.htm</ref>

Secondary renal hyperparathyroidism is a complication of chronic renal failure. This is due to hyperphosphataemia developing as a result of impaired glomerular filtration rate. Renal production of [[Calcium#Calcitriol|calcitriol]] is also reduced, exacerbating the resulting hypercalcaemia.

'''Secondary hyperparathyroidism''' can be either renal or nutritional in origin:

Secondary nutritional hyperparathyroidism is caused by excessive phosphorus intake causing a total or relative calcium deficiency by binding calcium in the gut and decreasing its absorption.  This encompasses bran disease in horses and also [[Metabolic Bone Disease|metabolic bone disease]] in reptiles.

Secondary '''renal hyperparathyroidism''' is a complication of '''chronic renal failure'''. This is due to '''hyperphosphataemia developing as a result of impaired glomerular filtration rate'''. Renal production of [[Calcium#Calcitriol|calcitriol]] is also reduced, exacerbating the resulting hypercalcaemia.

 

Secondary '''nutritional''' hyperparathyroidism is caused by excessive '''phosphorus intake''' causing a total or relative calcium deficiency by '''binding calcium in the gut and decreasing its absorption'''.  This category encompasses '''bran disease in horses and also [[Metabolic Bone Disease|metabolic bone disease]] in reptiles'''.

==Signalment==

==Signalment==