Background: We studied whether predialysis serum levels of positive acute phase markers such as alpha1-antitrypsin (AT), and complement components C3 and C4 could identify the presence of chronic inflammation in maintenance hemodialysis (HD) patients.
Methods/results: In 103 stable HD patients, AT directly correlated with C-reactive protein (CRP) (P < 0.005), alpha1 acid-glycoprotein (P < 0.005), fibrinogen ( P < 0.05), lipoprotein (a) (P < 0.01) and von Willebrand factor antigen (P < 0.05), while C3 and C4 were not related to any of these inflammatory markers. In the patients with elevated CRP and hypoalbuminemia, the mean AT value of 1.74 +/- 0.50 g/L was higher (P = 0.008) than that of 1.38 +/- 0.27g/L in the subjects with normal CRP and albumin. Using the above cut-off levels, the positive and negative predictive values of AT on the presence of severe inflammation were 0.86 and 0.62, respectively, and the sensitivity and specificity were 86% and 73%, respectively.
Conclusion: Serum AT levels above 1.74 g/L and below 1.38 g/L may select the HD patients with severe inflammation from those without. Measurements of C3 and C4 are not helpful in this situation.