Procalcitonin and C-reactive protein as predictors of blood culture positivity among hospitalised children with severe pneumonia in Mozambique

Trop Med Int Health. 2012 Sep;17(9):1100-7. doi: 10.1111/j.1365-3156.2012.03035.x. Epub 2012 Jul 19.

Abstract

Objectives: To evaluate the benefits of using procalcitonin (PCT) and C-reactive protein (CRP) as pre-screening tools to predict blood culture positivity among Mozambican children with clinical severe pneumonia (CSP).

Methods: 586 children <5 years with CSP and no concurrent malaria fulfilled criteria to be included in the study groups. We determined PCT and CRP for all children with positive bacterial culture (BC+ group, n = 84) and of a random selection of children with negative bacterial culture (BC- group, n = 246).

Results: PCT and CRP levels were higher in the BC+ group than the BC- one (PCT: median 7.73 versus 0.48 ng/ml, P < 0.001; CRP: 177.65 mg/l vs. 26.5 mg/l, P < 0.001). In multivariate analysis, PCT was the only independent predictor of the group. To be used as pre-screening tool, PCT presented higher specificities for predetermined sensitivities (≥85%) than CRP. Pursuing a sensitivity of 95%, PCT could reduce the need for bacterial culture by 49% and overall diagnosis costs by 7-35% [assuming variable costs for PCT measurement (ranging from 10 to 30 USD) and a fixed cost of 72.5 USD per blood culture].

Conclusions: Among hospitalised children with CSP and absence of concurrent malaria, PCT pre-screening could help reduce the number of blood cultures and diagnosis costs by specifically targeting patients more likely to yield positive results.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteremia / diagnosis*
  • Biomarkers
  • C-Reactive Protein / analysis*
  • C-Reactive Protein / metabolism
  • Calcitonin / blood*
  • Calcitonin Gene-Related Peptide
  • Child, Preschool
  • Female
  • Hospitalization / statistics & numerical data*
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Mozambique / epidemiology
  • Pneumonia, Bacterial / blood*
  • Pneumonia, Bacterial / diagnosis
  • Protein Precursors / blood*
  • Severity of Illness Index

Substances

  • Biomarkers
  • CALCA protein, human
  • Protein Precursors
  • Calcitonin
  • C-Reactive Protein
  • Calcitonin Gene-Related Peptide