The clinical value of PCT levels in bacteria identification in ICU patients with bloodstream infection

Objective To investigate the clinical value of procalcitonin (PCT) levels in bacteria identification in intensive care unit (ICU) patients with bloodstream infection. Methods There were 540 cases of patients with bloodstream infection in our ICU between December 2007 and December 2013. The PCT levels and bacteria were identified. The application effectiveness of PCT levels in the bacteria identification was studied. Results The G+ bacteria infection rate was 49.63% (268/540), G- bacteria infection rate was 38.52% (208/540), and the fungal infection rate was 11.85% (64/540). The patients of G- bacteria had significant difference with G+ bacteria and fungal infection (P 0.05). When PCT>2.04 ng/ml, the sensitivity and specificity that applying serum PCT level to identify the between G- and G+ bacteria were 82.18% and 76.09%, respectively. When PCT>3.16 ng/ml, the sensitivity and specificity that applying serum PCT level to identify the between G- and fungus bacteria were 59.42% and 65.73%, respectively. Conclusions The identification between G- bacteria and G+ bacteria, fungi with applying PCT level in bloodstream infections had high accuracy. When the PCT levels was greater than 2.04 ng/ml, the occurrence of G- bacteria was greater risk of infection. The accuracy of PCT level identifying the G+ bacteria and fungi was poor. Key words: Calcitonin/BL; Bacterial infections/BL/MI; Intensive care units