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 B 2 -microglobulin (B 2 -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 B 2 -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 B 2 -m. Any events (especially infections) in the preceding 10-day period were recorded. Results. At baseline, 100% of all B 2 -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 B 2 -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 B 2 -m to HD vintage. Conclusions. In this study, the strong positive correlation of B 2 -m to PCT probably signifies that the (mainly subclinical) infections increase B 2 -m production in CHD patients intensifying the problem of HD-related amyloidosis.

Diagnostic and prognostic value of procalcitonin for early intracranial infection after craniotomy

“…A diagnostic index with good sensitivity and specificity is highly essential in clinical settings to detect intracranial infection and guide clinicians to take necessary interventions, improve the prognosis of patients, and reduce the hospitalization time and economic burden. PCT has been widely studied in recent years for the early diagnosis of bacterial infection severity, treatment effect, disease prognosis and as reference for antibiotic use (24 –26). …”

Plasma calprotectin in chronically dialyzed end-stage renal disease patients

“…The concentration of beta-2 microglobulin in plasma and other body fluids increases in proportion to lost kidney function, as it is normally eliminated by the process of glomerular filtration followed by reabsorption and catabolism by the proximal tubular cells. Blumberg et al [30] reported correlation of beta-2 microglobulin with dialysis vintage, whereas beta-2 microglobulin production and tissue accumulation enhance the rate of progression of dialysis-related amyloidosis [31]. In our study, the significant correlation of plasmatic calprotectin with beta-2 microglobulin and with dialysis vintage could be explained by the increased time-dependent production and secretion of cytokines due to blood contact with bio-incompatible parts of HD membranes and the relevant impact of infections that activate immunocompetent cells.…”

Chronic inflammation in end-stage renal disease and dialysis

“…β2-microglobulin is considered as a prototypical middle molecule and is traditionally used as a marker of middle molecule removal. Both in pre-dialysis CKD and in dialysis patients [ 22 ], β2-microglobulin has been associated with several deleterious outcomes like pro-inflammatory processes [ 23 ], as well as with vascular stiffness [ 24 ], bone remodelling [ 25 ] or cognitive dysfunction [ 26 ]. Cytokines are another kind of middle molecule that show increased circulating concentrations along with the decline of renal function.…”