Mechanisms of hyperuricemia in cyclosporine-treated renal transplanted children.
Mechanisms of hyperuricemia were investigated in 19 pediatric renal transplant recipients 6 months after transplantation. 51Cr-EDTA, PAH, lithium and sodium clearances, 24-hour urinary creatinine and urate excretions were measured. Ten patients had hyperuricemia. The hyperuricemic patients had lower EDTA, PAH, and urate clearances (mean 69.5 vs. 92.5, p < 0.05, 234 vs. 421, p < 0.05 and 4.3 vs. 10.6 ml/min/1.73 m2, p < 0.001, respectively). Serum urate concentration correlated with cyclosporine dose (r = 0.46, p < 0.05) and inversely with urate (r = -0.88, p < 0.001), and lithium (r = -0.55, p < 0.05) clearances. Urate clearance showed a significant positive correlation with lithium clearance (r = 0.66, p = 0.01) and an inverse correlation with fractional proximal tubular reabsorption (r = -0.63, p = 0.02). Results were not influenced by diuretic administration. Our data support increased proximal tubular urate reabsorption rather than decreased secretion as the mechanism in cyclosporine-induced hyperuricemia.
Children's Hospital, University of Helsinki, Finland.
J
J
Laine
C
C
Holmberg
D001379:Azathioprine / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000097:blood; D016572:Cyclosporine / Q000627:therapeutic use*; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000276:immunology / Q000502:physiology*; D008775:Methylprednisolone / Q000627:therapeutic use; D011188:Potassium / Q000097:blood; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D013997:Time Factors; D014184:Transplantation, Homologous; D014527:Uric Acid / Q000097:blood*
D007166:Immunosuppressive Agents; D014527:Uric Acid; D016572:Cyclosporine; D003404:Creatinine; D001379:Azathioprine; D011188:Potassium; D008775:Methylprednisolone