Roles of serum procalcitonin and C-reactive protein in the diagnosis of nonneutrocytic ascitic spontaneous bacterial peritonitis in liver cirrhosis / 中华消化杂志

ABSTRACT

Objective To investigate the diagnostic value of serum procalcitonin (PCT) and C-reactive protein (CRP) in nonneutrocytic ascitic spontaneous bacterial peritonitis (NASBP).Methods From January 2012 to January 2015,patients with liver cirrhosis and ascites were restropectively enrolled.Patients were divided into NASBP group and non-infective ascites group.The receiver operating characteristics curve (ROC) was used for assessing diagnostic accuracy of serum PCT and CRP.Patients with conventional SBP were set as controls.Data between two groups were compared using t test,Rank sum test,x2 test or Fisher exact test.The areas under ROC curve or Youden indeces were compared using Z test.Results A total of 30 patients were collected in NASBP group,51 patients in non-infective ascites group and 33 patients in conventional SBP group.There were no statistically significant differences in PCT and CRP levels between NASBP group and conventional SBP group [0.70(0.25～2.45) μg/L,(21.85-±-16.46) mg/L;0.90(0.33～3.56) μg/L,(31.78-±26.74) mg/L] both P＞0.05,and were both significantly higher than those of non-infective ascites group (0.20 (0.07 ～ 0.40) μg/L,Z=-3.38,t=4.64;(7.19±7.04) mg/L,Z=-3.89,t=-5.17,both P＜0.05).The optimal cut-off value of PCT and CRP in the diagnosis of NASBP was 0.43 ng/mL and 12.76 mg/L,respectively.According to the cut-off value above,PCT,CRP and PCT plus CRP in series and in parallel in the diagnosis of NASBP,the areas under curves were 0.725,0.848,0.737 and 0.806,respectively,and there was no significant difference in pairwise comparison between groups.The sensitivities were 70.0％,70.0％,53.3％ and 86.7％,respectively,there were statistically significant differences between inparallel and any other method (Fisher exact test,all P＜ 0.05).And there was no statistically significant difference (all P＞0.05).The specificities were 76.5％,88.2％,94.1％ and 74.5％,respectively.There was no statistically significant difference in PCT and CRP between combination in parallel and in series,while the differences in the other pairwise comparisons of combinations were statistically significant (Fisher exact test,P＜0.05).The Youden's indexes were 0.465,0.582,0.474 and 0.612,respectively,there was no statistically significant difference in pairwise comparison between groups (all P＞0.05).Conclusions All of serum PCT,CRP and the combination of them have good diagnostic value in NASBP with their own advantages which should be selected based clinical needs.