Strong Correlation of B₂-Microglobulin (B₂-m) with Procalcitonin (PCT) in the Serum of Chronic Hemodialysis Patients: A Role for Infections in the Dialysis-Related Amyloidosis?

Abstract

Introduction. Infections trigger the activation of defensive cells capable to produce and release B₂-microglobulin (B₂-m). Procalcitonin (PCT), secreted by a wide range of human cells, included the aforementioned defensive cells, is generally considered a sensitive and specific marker of infection. In this prospective study, we examined the possibility that infections, as detected by increased levels of PCT, increase the serum levels of B₂-m in chronic hemodialysis (CHD) patients, possibly affecting the rate of progression of dialysis-related amyloidosis (DRA). Methods. For a period of four months, 76 CHD patients, 45 men/31 women, mean age 63 ± 15.7 years, with no residual renal function and in HD for 46 ± 50 months were studied bimonthly. Blood was drawn, at baseline T(0), two months T(2), and four months T(4), for measuring hematocrit (Ht), white blood cells (WBC), erythrocyte sedimentation rate (ESR), blood urea and serum creatinine, protein (albumin, globulin), C-reactive protein (CRP), and PCT και B₂-m. Any events (especially infections) in the preceding 10-day period were recorded. Results. At baseline, 100% of all B₂-m measurements were abnormal (>2.4 mg/L), 13.4% of PCT values were increased (>1.5 ng/mL), and 49.4% of CRP values exceeded the lower limit of 5 mg/L with no statistically significant differences between the results of the three periods of the study. Statistically significant, in all periods, was the linear positive correlation of B₂-m with PCT (T[0]: p < 0.001, T[2]: p < 0.004, T[4]: p < 0.001). Also, statistically significant (p < 0.005) was the positive correlation of B₂-m to HD vintage. Conclusions. In this study, the strong positive correlation of B₂-m to PCT probably signifies that the (mainly subclinical) infections increase B₂-m production in CHD patients intensifying the problem of HD-related amyloidosis.

Keywords:

• hemodialysis
• procalcitonin
• B₂-microglobulin