title: The role of procalcitonin in febrile neutropenic patients: review of the literature.
abstract: BACKGROUND
  Procalcitonin (PCT) has been increasingly used as an inflammatory marker to identify patients with systemic infection. Moreover, PCT guidance allowed significant reduction of antibiotic therapy in patients with respiratory disease. The aim of this qualitative review was, therefore, to evaluate the role of PCT measurements in febrile neutropenic patients in differentiating between various causes of fever and to investigate the value of PCT levels in terms of diagnosing infection or predicting outcome in these patients.
  
  
  METHODS
  A MEDLINE search was performed using the keyword 'procalcitonin' crossed with 'febrile neutropenia', 'neutropenia', 'fever', 'bone marrow transplantation', and 'stem cell transplantation', and limited to human studies published between January 1990 and October 2006. Bibliographies of identified articles were also searched. Predefined variables were collected from the articles, including year of publication, study design, number of patients included, age group, disease group, markers other than PCT, and study results.
  
  
  RESULTS
  From the 30 articles included, PCT seems to be able to discriminate fever due to systemic forms of infection from non-infectious etiologies. Patients with fungal infection may have a delayed increase in PCT levels. PCT has a minimal role, if any, in discriminating Gram-negative from Gram-positive infections. PCT may be useful in outcome prediction in patients with febrile neutropenia but is not superior to interleukin-6 or C-reactive protein concentrations for this purpose.
  
  
  CONCLUSIONS
  Despite lack of standard definitions, heterogeneity of study populations, and small numbers of patients included in some studies, our review provides important insight into the value of PCT as a diagnostic and prognostic tool in patients with febrile neutropenia.
authors.affiliation: Department of Anaesthesiology and Intensive Care, Friedrich-Schiller-University, Erlanger Allee 103, Jena, Germany.
authors.forename: Y
authors.initials: Y
authors.lastname: Sakr
authors.forename: C
authors.initials: C
authors.lastname: Sponholz
authors.forename: F
authors.initials: F
authors.lastname: Tuche
authors.forename: F
authors.initials: F
authors.lastname: Brunkhorst
authors.forename: K
authors.initials: K
authors.lastname: Reinhart