Augmented polymorphonuclear chemiluminescence in patients with secondary hyperparathyroidism

Area of Science:

• Nephrology
• Immunology
• Endocrinology

Background:

• Secondary hyperparathyroidism (HPT) is common in uremia.
• Altered leukocyte function is observed in uremic patients.
• The specific role of secondary HPT in immune dysfunction requires clarification.

Purpose of the Study:

• To investigate the effect of secondary HPT on polymorphonuclear leukocyte (PMN) function.
• To assess the impact of serum intact parathyroid hormone (iPTH) levels on PMN chemiluminescence (CL).
• To evaluate changes in PMN function following parathyroidectomy.

Main Methods:

• Studied two groups of patients: mild (Group 1) and severe (Group 2) secondary HPT.
• Assessed PMN chemiluminescence (CL) in the presence of autologous and normal serum.
• Conducted cross-incubation studies with patient sera and normal PMNs.
• Monitored iPTH levels and other biochemical markers (calcium, phosphorus, creatinine, BUN).
• Evaluated PMN function before and after subtotal parathyroidectomy.

Main Results:

• PMNs from patients with severe secondary HPT (Group 2) showed significantly augmented CL with autologous serum.
• Sera from Group 2 patients enhanced CL in normal PMNs, indicating serum factors mediate the effect.
• PMNs from Group 2 patients exhibited reduced CL with normal serum.
• Successful parathyroidectomy led to decreased iPTH levels and improved PMN CL and serum-induced CL.
• The observed effects did not correlate with calcium, phosphorus, creatinine, or BUN levels.

Conclusions:

• Secondary HPT is directly or indirectly responsible for altered leukocyte function in uremia.
• Marked elevation of iPTH is particularly associated with impaired PMN function.
• Parathyroidectomy can reverse the functional changes in leukocytes associated with secondary HPT.