title: The behavior and diagnostic utility of procalcitonin and five other inflammatory molecules in critically ill patients with respiratory distress and suspected 2009 influenza a H1N1 infection.
abstract: OBJECTIVE
  During the 2009 influenza A H1N1 pandemic, it became difficult to differentiate viral infections from other conditions in patients admitted to the intensive care unit. We sought to evaluate the behavior and diagnostic utility of procalcitonin, C-reactive protein and four other molecules in patients with suspected 2009 Influenza A H1N1 infection.
  
  
  METHODS
  The serum levels of procalcitonin, C-reactive protein, tumor necrosis factor α, interferon γ, interleukin 1β, and interleukin 10 were tested on admission and on days 3, 5, and 7 in 35 patients with suspected 2009 H1N1 infection who were admitted to two ICUs.
  
  
  RESULTS
  Twelve patients had confirmed 2009 influenza A H1N1 infections, 6 had seasonal influenza infections, and 17 patients had negative swabs. The procalcitonin levels at inclusion and on day 3, and the C-reactive protein levels on day 3 were higher among subjects with 2009 influenza A H1N1 infections. The baseline levels of interleukin 1b were higher among the 2009 influenza A H1N1 patients compared with the other groups. The C-reactive protein levels on days 3, 5, and 7 and procalcitonin on days 5 and 7 were greater in non-surviving patients.
  
  
  CONCLUSIONS
  Higher levels of procalcitonin, C-reactive protein and interleukin-1β might occur in critically ill patients who had a 2009 H1N1 infection. Neither procalcitonin nor CRP were useful in discriminating severe 2009 H1N1 pneumonia. Higher levels of CRP and procalcitonin appeared to identify patients with worse outcomes.
authors.affiliation: Universidade Federal de Minas Gerais, Faculdade de Medicina (UFMG), Hospital das Clínicas UFMG, Unidade Coronariana, Belo Horizonte/MG, Brazil. mbspaiva@yahoo.com.br
authors.forename: Mariana Benevides Santos
authors.initials: MB
authors.lastname: Paiva
authors.forename: Fernando Antônio
authors.initials: FA
authors.lastname: Botoni
authors.forename: Antônio Lúcio
authors.initials: AL
authors.lastname: Teixeira
authors.forename: Aline Silva de
authors.initials: AS
authors.lastname: Miranda
authors.forename: Clara Rodrigues Alves de
authors.initials: CR
authors.lastname: Oliveira
authors.forename: Jamila de Oliveira
authors.initials: Jde O
authors.lastname: Abrahão
authors.forename: Guilherme Marques
authors.initials: GM
authors.lastname: Faria
authors.forename: Vandack
authors.initials: V
authors.lastname: Nobre
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D016638:Critical Illness; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000150:complications / Q000175:diagnosis*; D053583:Interleukin-1beta / Q000097:blood*; D008297:Male; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D060888:Real-Time Polymerase Chain Reaction; D012128:Respiratory Distress Syndrome / Q000209:etiology*; D014777:Virus Diseases / Q000175:diagnosis; D055815:Young Adult
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D053583:Interleukin-1beta; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide