Measurement | Criteria |
---|---|
Age of patient | < 50 years |
Serum calcium concentration (above the upper reference value) | > 0.25 mmol/L (1.0 mg/dL) |
Skeletal injury | bone mineral density (DXA): T-score < -2.5 SD* |
spinal fracture (proven by XR, CT, MRI or VFA) | |
Renal impairment | creatinine clearance < 60 mL/min |
kidney stones or nephrocalcinosis (proven by XR, US or CT) | |
24-hour calcium in urine > 10 mmol/L (400 mg/day) or increased risk for kidney stones based on biochemical analysis |
Organ system | Function of PTH |
---|---|
Kidneys (leading role) | It increases calcium and decreases phosphate reabsorption, stimulates calcitriol production by increasing the synthesis of the enzyme 1-α hydroxylase in proximal tubules. |
Skeletal | It raises calcium levels in blood by increasing bone destruction (via osteoblast-mediated activation of osteoclasts) and decreasing the formation of new bone. |
Gastrointestinal system | It increases calcium absorption by stimulating the production of 1,25-dihydroxycholecalciferol. |
Other (minor role, experimental) | Metabolic effects (reduced glucose tolerance, changes in fat metabolism), effects on the liver, adipose tissue, cardiovascular system, neuromuscular function. |
Organ system | Symptoms and clinical signs |
---|---|
General | anorexia, polyuria, polydipsia, weight gain, anaemia |
Skeletal | |
Kidney | kidney stones, renal parenchymal calcifications, nephrocalcinosis, chronic renal impairment |
Neuromuscular | proximal muscle weakness, depression, decline in cognitive ability, psychosis |
Cardiovascular | arterial hypertension, arrhythmias, left ventricular hypertrophy, vascular wall and myocardial calcification |
Gastrointestinal | nausea, vomiting, constipation, ulcer disease, pancreatitis |
Rheumatological | gout, pseudogout |