Objective: The increase in serum procalcitonin (PCT) levels is a marker of severe systemic inflammation due to bacterial infection and renal excretion plays an important role in its elimination. The aim of this retrospective study is to investigate the relationship between serum inflammatory markers such as PCT, C-reactive protein(CRP), albumin, prealbumin levels, leucocyte count and estimated glomerular filtration rate(EGFR).

Materials and Methods: 1792 patients (1110 male, 682 female) with age mean±SD 54.4±20.2 years were included in this study. Patients were classified into two groups as; with infection (n=1715) and without infection (n=77), depending on CRP, albumin, prealbumin levels and leucocyte count. EGFRs of all patients were calculated and infectious group was classified into 3, as normal(EGFR³90, n=1007), mildly decreased(EGFR=60-89, n=229), modarete / severely decreased(EGFR<60, n=479). Serum PCT, CRP, albumin and prealbumin were statistically compared between groups. In both groups with and without infection correlation between EGFR and variables were assessed.

Results: In infectious group, patients with modarete/severely decreased EGFR had PCT, CRP levels and leucocyte count significantly higher than normal (all, p<0.001), mildly decreased EGFR (p<0.001, p=0.019, p=0.014, respectively) and albumin levels were significantly lower (p< 0.001). Patients with mildly decreased EGFR had significantly higher PCT and CRP levels than normal EGFR patients (p<0.001, p=0.003,respectively) and albumin and prealbumin levels were significantly lower (p=0.022, p<0.001 respectively). In infectious group, EGFR was negatively correlated with CRP (r=-0.219, p<0.001) and PCT (r=-0.500, p<0.001) and in noninfectious group EGFR was negatively correlated with PCT (r=-0.291, p<0.001).

Conclusion: PCT is an efficacious prognostic factor for systemic inflammation proceeding to renal dysfunction. Because renal dysfunction may effect PCT levels; the prognostic evaluation must be one of the concerns and PCT levels should be evaluated with EGFR, calculated just with age and serum creatinine.