Diagnosis of sHPT made with blood work showing normal or low calcium, with elevated parathyroid hormone (PTH) levels.
- PTH levels are appropriately elevated to compensate for chronic hypocalcemia (low calcium).
Most causes of sHPT (Vit D deficiency, gastric bypass surgery / celiac disease, and renal leak) are treated medically (see Hyperparathyroidism Overview for more details).
- The exception to this is chronic or progressive kidney disease.
Effects of chronic or progressive kidney disease causing sHPT.
- As PTH levels increase higher and for a longer period:
- Phosphorous levels can increase dangerously high.
- Bones can progressively thin (renal osteodystrophy) causing bone pain and increased risk for fracture from a simple fall.
- Muscle weakness develops.
- Increased cardiovascular morbidity (heart attack, heart failure, stroke, and high blood pressure) can occur.
Treatment of progressive or chronic kidney disease causing sHPT.
- Initial treatment should always be medical management:
- ‘Calcimimetics’ – suppress PTH production while minimizing intestinal calcium and Phosphorous absorption (keeps calcium and phosphorous levels low).
- Cinacalcet 2004 FDA approval for sHPT patients on dialysis (prescribed by a nephrologist).
- Parathyroidectomy (surgery) for sHPT is considered when medical management with calcimimetics has failed:
- 2009 KDIGO guidelines – CKD stages 3 – 5 with:
- PTH levels > 9 x normal levels (~ 700 depending on the lab test being used).
- Uncontrolled hyperphosphatemia (high phosphorous levels).
- Anticipated kidney transplant in the next 6 months.
- Bone fracture attributed to renal osteodystrophy (bone thinning).
- Calciphylaxis – blood vessels near the skin calcify, the skin loses blood supply, and a painful ulcer forms on the skin.
- Extra-skeletal calcification – calcification outside of the bones which can include the cornea, joints, lungs, blood vessels.
- Skin itching, muscle weakness, and bone / joint pain effecting quality of life.
- Parathyroidectomy in sHPT has been shown to improve:
- Pruritis (itching), muscle function, left ventricular (heart) function, anemia, health related quality of life, cognition, coronary artery calcification, rate of bone fractures, mortality 3 years after surgery.
- For more information read Parathyroidectomy for Kidney Related Hyperparathyroidism.
