Endocrine Abstracts

Introduction: The decline of renal function is closely associated to increased parathyroid hormone secretion, resulting to secondary hyperparathyroidism because of: 1) hypocalcemia; 2) hyperphosphatemia; 3) reduced activity of calcitriol; 4) skeletal resistance to the calcemic action of parathyroid hormone (PTH) and 5) reduced secretion of the calcium-sensing receptor (CaSR) in the parathyroid glands.

The retention of phosphorus is considered to take an important role in the evolution of secondary hyperparathyroidism.

The recent use of vitamin D analogues (3rd G of calcitriol–elocalcitol, paricalcitol-) which bare eclectic affinity to its receptors repress the infusion of PTH and improve the secondary hyperparathyroidism.

Aim: The study of calcium (Ca), phosphorus (P) and intact parathyroid hormone (i-PTH) serum disturbances in end stage renal disease patients who were on haemodialysis (eGFR<15 ml/min per 1.73 m²).

Patients and methods: In 27 individuals undergoing hemodialysis (HD), the levels of calcium, phosphorus were determined using photometric method by the Roche biochemical analyser Modular P 800 and the i-PTH levels were measured by electrochemiluminescence method in Modular Analytics E 170 immunoassay analyser. The same parameters were determined in a control group (CG) consisting of 44 normal subjects.

Results: There was a statistically significant difference in i-PTH levels among HD and controls groups (P<0.001).

Statistically significant difference (P<0.001) is also observed in the levels of P between the patients (5.62±1.29 mg/dl) and the control group (3.78±0.51 mg/dl).

The levels of Ca in the control group (9.44±0.47 mg/dl) were significantly higher than the HD group (8.35±1.07 mg/dl) (P<0.001).

Conclusions: Even after the use of the new calcitriol analogues, secondary hyperparathyroidism continues to exist in chronically undergoing hemodialysis patients, though a number of patients present normal i-PTH values. The disturbances in calcium and phosphorus concentrations are noticed to be milder.