title: [Diagnostic value of human neutrophil peptide in spontaneous bacterial peritonitis].
abstract: OBJECTIVE
  To investigate the correlation between human neutrophil peptide (HNP) and spontaneous bacterial peritonitis (SBP) in order to assess the diagnostic value of quantitative measurement of these alpha-defensins.
  
  
  METHODS
  Seventy-seven patients with cirrhosis and ascites were divided into two groups according to diagnosis of SBP (n = 45 with SBP and n = 32 without SBP). Twenty-eight healthy individuals were analyzed as controls. HNP was detected by double-antibody sandwich assay. Peripheral white blood cell (WBC) counts, neutrophil ratio, and levels of procalcitonin (PCT) and C-reactive protein (CRP) were determined by standard methods. Receiver operating characteristic (ROC) curves were used to compare the diagnostic values of HNP, PCT and CRP in SBP.
  
  
  RESULTS
  There were no significant differences between the three groups (SBP, non-SBP, and healthy controls) for WBC count ((6.01+/-2.25)*109 /L, (4.85+/-1.94)*109 /L, and (5.49+/-1.76)*109 /L; F = 2.91, P more than 0.05) and neutrophil ratio (70.70%+/-10.42%, (68.20%+/-8.97%, and 69.50%+/-8.69%; F = 3.07, P more than 0.05). However, compared to the non-SBP group and the healthy controls, the SBP group showed significantly higher levels of HNP ((9.99+/-3.33) ng/ml and (8.92+/-2.30) ng/ml vs. (17.66+/-6.40) ng/ml; q = 3.20 vs. 3.52, P less than 0.05), serum CRP ((15.08+/-9.95) ng/ml and (5.96+/-2.91) ng/ml vs. (31.32+/-18.65) mg/L; q = 11.03 vs. 3.69, P less than 0.05), and positive rate of PCT (25.0% and 10.0% vs. 62.2%; X2 = 10.41 vs. 15.40, P less than 0.0125). The areas under the curve (AUC) showed the following descending trend: HNP more than PCT more than CRP (0.719, 0.707, and 0.629 respectively). Using cut-off points of 10 ng/ml for HNP, 0.5 ng/ml for PCT, and 8 mg/L for CRP, the respective sensitivities for diagnosis of SBP were 71.1%, 62.2%, and 73.3%, the respective specificities were 71.9%, 75.0%, and 56.3%, and the respective Youden's indexes were 0.430, 0.372, and 0.296.
  
  
  CONCLUSIONS
  HNP is closely related to SBP and can diagnose SBP as reliably as PCT. CRP may help to diagnose SBP, but the results from routine blood testing did not show sufficient statistical significance for diagnosing SBP.
authors.affiliation: School of Medicine, Shandong University, Jinan 250012, China.
authors.forename: Yan-xue
authors.initials: YX
authors.lastname: Gong
authors.forename: Su-nan
authors.initials: SN
authors.lastname: Cui
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Ming-ming
authors.initials: MM
authors.lastname: Wang
authors.forename: Nan
authors.initials: N
authors.lastname: Guo
mesh_terms: D000328:Adult; D000368:Aged; D001424:Bacterial Infections / Q000097:blood / Q000175:diagnosis*; D002097:C-Reactive Protein / Q000378:metabolism; D002116:Calcitonin / Q000097:blood; D015740:Calcitonin Gene-Related Peptide; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010538:Peritonitis / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology; D011498:Protein Precursors / Q000097:blood; D023084:alpha-Defensins / Q000097:blood*
chemical_list: C000606589:CALCA protein, human; D011498:Protein Precursors; D023084:alpha-Defensins; C406413:human neutrophil peptide 1; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide