[Oxidative potential of neutrophils in cyclosporine A treated children with idiopathic nephrotic syndrome]

Abstract

Cyclosporine A (CsA) is a potent immunosuppressant introduced to the treatment of idiopathic nephrotic syndrome (INS) in children. Besides beneficial effects on the clinical course of the disease, this drug may also influence the function of first line defence cells. The aim of the study was to assess the granulocyte generation of reactive oxygen intermediates (ROI) in children suffering from idiopathic nephrotic syndrome treated with cyclosporine A.

Material and methods: The study group consisted of 10 children (aged 4-18 yrs.) in at least 2 month-long remission of steroid-dependent INS treated with CsA (group A), 16 children in long-term remission (at least 18 months without treatment) of INS (group B). Twelve healthy age-matched children (group C) constituted control group. ROI generation was measured by the luminol-dependent chemiluminescence of whole blood using MLX Microtiter Plate Luminometer, Dynex. The following parameters were evaluated: spontaneous chemiluminescence, chemiluminescence induced by formyl-Met-Leu-Phe (fMLP), opsonized zymosan (OZ) and phorbol acetate (PMA).

Results: The primary results were corrected according to the absolute number of neutrophils and hemoglobin concentration. Final results were presented as relative luminescence units RLUmax (Relative Light Units Max). In children treated with CsA we found significantly increased spontaneous, fLMP and OZ stimulated chemiluminescence activity compared to patients from group C. Chemiluminescence tests conducted in the long-term remission of INS gave similar results with respect to neutrophil reactivity. CONCLUSION. The neutrophil function measured by spontaneous and receptor-dependent oxidative burst in children with either cyclosporine-induced or long-term treatment-free remission seems to be upregulated. The potential clinical implications of these observations remain to be established.