Procalcitonin (PCT) and C-reactive Protein (CRP) as severe systemic infection markers in febrile neutropenic adults
1 Disciplina de Hematologia e Hemoterapia – Departamento de Clínica Médica at the Faculty of Medicine of the University of São Paulo, Brazil
2 Pesquisa e Desenvolvimento – Departamento de Doenças Infecciosas e Parasitárias at the Faculty of Medicine of the University of São Paulo, LIM54, Brazil
3 NUCAMP – Núcleo de Consultoria e Apoio em Metodologia de Pesquisa e Estatística, Departamento de Pediatria at the Faculty of Medicine of the University of São Paulo, Brazil
4 Av. General Ataliba Leonel, 93 cj112, São Paulo – SP, 02033-000, Brazil
BMC Infectious Diseases 2007, 7:137 doi:10.1186/1471-2334-7-137Published: 22 November 2007
Procalcitonin (PCT) is an inflammatory marker that has been used as indicator of severe bacterial infection. We evaluated the concentrations of PCT as a marker for systemic infection compared to C-reactive protein (CRP) in patients neutropenic febrile.
52 adult patients were enrolled in the study. Blood sample was collected in order to determine the serum concentrations of PCT, CRP and other hematological parameters at the onset of fever. The patients were divided into 2 groups, one with severe infection (n = 26) and the other in which the patients did not present such an infection (n = 26). Then PCT and CRP concentrations at the fever onset were compared between groups using non parametric statistical tests, ROC curve, sensitivity, specificity, likelihood ratio, and Spearman's correlation coefficient.
The mean of PCT was significantly higher in the group with severe infection (6.7 ng/mL versus 0.6 ng/mL – p = 0.0075) comparing with CRP. Serum concentrations of 0.245 ng/mL of PCT displayed 100% de sensitivity and 69.2% specificity. PCT concentrations of 2,145 ng/mL presented a likelihood ratio of 13, which was not observed for any concentration of CRP.
PCT seems to be an useful marker for the diagnosis of systemic infection in febrile neutropenic patients, probably better than CRP.