Clinical verification of serum procalcitonin measurement in sepsis

: To evaluate the clinical application of measuring procalcitonin (PCT) level for diagnosis of bacterial sepsis in patients with and without systemic inflammatory response syndrome(SIRS), we studied the relationship between blood culture (BC) and serum PCT level in clinical 207 cases. In addition, we evaluated the time courses of PCT and other inflammatory markers: tumor necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6), E-selectin, WBC count and C-reactive protein (CRP) in 5 bacterial septic patients with SIRS. Serum PCT showed sensitivity of 41% and specificity of 61%, while BC showed specificity of 88%. In 27 BC-positive cases, serum PCT was significantly elevated in gram-negative bacterial sepsis. We observed 11 cases with BC(+) and serum PCT below 0.5 ng/ml. Major causes of these discrepancies were probably due to gram-positive bacterial infection, local bacterial infection or pretreatment with broad-spectrum antibiotics. In contrast, 10 cases with BC(-) and serum PCT over 10 ng/ml were presumably due to some cytokine elevation caused by virus infection or collagen diseases. In 5 cases studied for inflammatory markers, TNF-alpha level elevated earlier than the others and followed by PCT, IL-6, WBC, CRP, and E-selectin. It was suggested that the measurement of serum procalcitonin in septic patients is clinically useful marker to diagnose gram-negative bacterial septic patients with SIRS.