Serum concentration of cystatin C is not affected by cellular proliferation in patients with proliferative haematological disorders

Background Recent reports have shown elevated concentrations of serum cystatin C (CC) in patients with solid tumours. The aim of our study was to investigate whether patients with proliferative haematological disorders have increased serum concentrations of CC compared with normal subjects. Methods Full blood count, serum CC, beta(2)-microglobulin (beta(2)M) and serum creatinine were determined in 27 apparently healthy subjects and 35 patients with proliferative haematological disorders. Creatinine clearance was calculated using the Cockroft-Gault formula. Results CC and beta(2)M showed a significant correlation with each other (r = 0.96, P<0.0001). Serum beta(2)M (P = 0.001) and the serum beta(2)M: CC ratio (P = 0.001) were significantly higher in the patients with normal renal function than in controls, but serum CC was not significantly different (P = 0.08). CC did not show a significant correlation with blood count parameters. Discussion Compared with beta(2)M and the beta(2)M:CC ratio, serum CC is not influenced by cell proliferation in haematological disorders.