title: Comparison of 16S rRNA gene PCR and blood culture for diagnosis of neonatal sepsis.
abstract: Septicemia is a common cause of morbidity and mortality among newborns in the developing world. However, accurate clinical diagnosis of neonatal sepsis is often difficult because symptoms and signs are often nonspecific. Blood culture has been the gold standard for confirmation of the diagnosis. However, the sensitivity is low and results are usually not promptly obtained. Therefore, the diagnosis of sepsis is often based on clinical signs in association with laboratory tests such as platelets count, immature/total neutrophils ratio (I/T), and a rise in C-reactive protein (CRP). Polymerase chain reaction (PCR) methods for the detection of neonatal sepsis represent new diagnostic tools for the early identification of pathogens.
  
  
  METHODS
  During a 4-month prospective study, 16S rRNA PCR was compared with conventional blood culture for the diagnosis of neonatal bacterial sepsis. In addition, the relationship between known risk factors, clinical signs, laboratory parameters, and the diagnosis of sepsis was considered.
  
  
  RESULTS
  Sepsis was suspected in 706 infants from the intensive neonatal care unit. They all were included in the study. The number of positive cultures and positive PCR results were 95 (13.5%) and 123 (17.4%), respectively. Compared with blood culture, the diagnosis of bacterial sepsis by PCR revealed a 100.0% sensitivity, 95.4% specificity, 77.2% positive predictive value, and 100.0% negative predictive value. In this study, Apgar scores at 5 min, weight, icterus, irritability, feeding difficulties, gestational age (GA), premature rupture of membrane (PRM), platelets count, I/T, and a marked rise in CRP were important in establishing the diagnosis of sepsis in the newborn. In addition, weight, GA, PRM, irritability, duration of antibiotic usage, mortality rate, and number of purulent meningitis cases were significantly different between early-onset sepsis and late-onset sepsis.
  
  
  CONCLUSIONS
  16S rRNA PCR increased the sensitivity in detecting bacterial DNA in newborns with signs of sepsis, allowed a rapid detection of the pathogens, and led to shorter antibiotic courses. However, uncertainty about the bacterial cause of sepsis was not reduced by this method. 16S rRNA PCR needs to be further developed and improved. Blood culture is currently irreplaceable, since pure isolates are essential for antimicrobial drug susceptibility testing.
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: C L
authors.initials: CL
authors.lastname: Liu
authors.affiliation: Department of clinical laboratory, children's Hospital, 430030 Wuhan, PR China.
authors.forename: H W
authors.initials: HW
authors.lastname: Ai
authors.affiliation: Department of clinical laboratory, women and children hospital, 430030 Wuhan, PR China.
authors.forename: W P
authors.initials: WP
authors.lastname: Wang
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of clinical laboratory, children's Hospital, 430030 Wuhan, PR China.
authors.forename: H B
authors.initials: HB
authors.lastname: Hu
authors.affiliation: Department of clinical laboratory, women and children hospital, 430030 Wuhan, PR China.
authors.forename: T
authors.initials: T
authors.lastname: Ye
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: X H
authors.initials: XH
authors.lastname: Zhu
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: F
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: Y L
authors.initials: YL
authors.lastname: Liao
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: G
authors.initials: G
authors.lastname: Ou
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: L
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: M
authors.initials: M
authors.lastname: Sun
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: C
authors.initials: C
authors.lastname: Jian
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Chen
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: L
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: B
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: L
authors.initials: L
authors.lastname: Tian
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: B
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China.
authors.forename: S
authors.initials: S
authors.lastname: Yan
authors.affiliation: Department of clinical laboratory, Tongji hospital, Tongji medical college, Huazhong university of science and technology, 430030 Wuhan, PR China. Electronic address: tjszyong@163.com.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Sun
mesh_terms: D001424:Bacterial Infections / Q000175:diagnosis* / Q000235:genetics* / Q000401:mortality; D001431:Bacteriological Techniques; D001769:Blood / Q000382:microbiology*; D002681:China; D003470:Culture Media; D003906:Developing Countries; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008297:Male; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012307:Risk Factors; D018805:Sepsis / Q000175:diagnosis* / Q000235:genetics* / Q000401:mortality; D015996:Survival Rate; D062606:Tertiary Care Centers
chemical_list: D003470:Culture Media; D012336:RNA, Ribosomal, 16S