title: The utility of biomarkers in differentiating bacterial from non-bacterial lower respiratory tract infection in hospitalized children: difference of the diagnostic performance between acute pneumonia and bronchitis.
abstract: The aim of this study is to investigate the utility of several biomarkers in differentiating bacterial community-acquired lower respiratory tract infection (CA-LRTI) from non-bacterial CA-LRTI in children and the difference of their diagnostic performance between pneumonia and bronchitis. A retrospective cohort study composed of 108 pediatric patients hospitalized for CA-LRTI was performed during 2010-2013. Based on the findings of chest X-ray and sputum samples, patients were divided into 4 categories, group of bacterial pneumonia or bronchitis, and non-bacterial (viral or etiology-unknown) pneumonia or bronchitis. Peripheral white blood cell and neutrophil counts, and serum C-reactive protein (CRP) and procalcitonin (PCT) levels were compared among the 4 groups. Finally, 54 patients were the subject of this study. In the patients with pneumonia, serum CRP and PCT levels were significantly elevated in the group of bacterial pneumonia (CRP: p = 0.02, PCT: p = 0.0008). The area under the receiver operating characteristic curve for PCT for distinguishing between bacterial and non-bacterial pneumonia was the largest, and sensitivity, specificity, positive predictive value and negative predictive value of PCT were best among 4 markers. On the other hand, in the patients with bronchitis, neutrophil count was significantly decreased in non-bacterial bronchitis whereas no significant differences of WBC count, CRP level or PCT level were seen. In conclusion, PCT was the most useful marker to differentiate bacterial pneumonia whereas neutrophil count contributed most to the discrimination of bacterial bronchitis. The diagnostic performance of biomarkers may be different between pneumonia and bronchitis.
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan. Electronic address: hoshina@pediatr.med.kyushu-u.ac.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hoshina
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Etsuro
authors.initials: E
authors.lastname: Nanishi
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kanno
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Hisanori
authors.initials: H
authors.lastname: Nishio
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kusuhara
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Hara
mesh_terms: D000293:Adolescent; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D001991:Bronchitis / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology; D002097:C-Reactive Protein / Q000378:metabolism*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000382:microbiology; D003937:Diagnosis, Differential; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils; D018410:Pneumonia, Bacterial / Q000097:blood / Q000175:diagnosis*; D011024:Pneumonia, Viral / Q000097:blood / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011498:Protein Precursors / Q000097:blood*; D012372:ROC Curve; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide
keywords: C-reactive protein; Diagnostic performance; Lower respiratory tract infection; Neutrophil count; Procalcitonin; White blood cell count