Diagnostic Accuracy of Serum Procalcitonin for Spontaneous Bacterial Peritonitis Due to End-stage Liver Disease: A Meta-analysis

Abstract

Early diagnosis and prompt treatment of spontaneous bacterial peritonitis (SBP) due to end-stage liver disease is vital to shorten hospital stays and reduce mortality. Many studies have explored the potential usefulness of serum procalcitonin (PCT) in predicting SBP. The aim of this study is to evaluate the overall diagnostic accuracy of PCT levels for identifying SBP due to end-stage liver disease.After performing a systematic search of the Medline, Embase, and Cochrane databases for studies that evaluated the diagnostic role of PCT for SBP, sensitivity, specificity, and other measures of accuracy of PCT concentrations in serum for SBP diagnosis were pooled using random-effects models. A summary receiver operating characteristic curve was used to summarize overall test performance.Seven publications met the inclusion criteria covering 742 episodes of suspected SBP along with 339 confirmed cases. The summary estimates for serum PCT in the diagnosis of SBP attributable to end-stage liver disease were: sensitivity 0.82 (95% CI 0.79-0.87), specificity 0.86 (95% CI 0.82-0.89), positive likelihood ratio 4.94 (95% CI 2.28-10.70), negative likelihood ratio 0.22 (95% CI 0.10-0.52), and diagnostic OR 22.55 (95% CI 7.01-108.30). The area under the curve was 0.92. There was evidence of significant heterogeneity but no evidence of publication bias.Serum PCT is a relatively sensitive and specific test for the identification of SBP. However, due to the limited high-quality studies available, medical decisions should be carefully made in the context of both PCT test results and other clinical findings.

FIGURE 1

Flowchart showing the process for selecting eligible studies in this meta-analysis.

FIGURE 2

Methodological evaluation of the included studies according to QUADAS-2. Graphical display of the QUADAS-2 results showing the proportion of studies with high, low, or unclear risk levels of bias.QUADAS-2 = Quality Assessment of Diagnostic Accuracy Studies-2.

FIGURE 3

Forest plot of estimates of sensitivity and specificity for procalcitonin assays in the diagnosis of SBP. The point estimates of sensitivity and specificity from each study are shown as solid circles. Error bars indicate 95% CIs. CI = confidence interval, SBP = spontaneous bacterial peritonitis.

FIGURE 4

Subgroup analysis of prospective versus retrospective studies of procalcitonin in the diagnosis of SBP. The point estimates of sensitivity and specificity from each study are shown as solid circles. Error bars indicate 95% CIs. CI = confidence interval, SBP = spontaneous bacterial peritonitis.

FIGURE 5

Subgroup analysis of underlying diseases on the effect of procalcitonin in the diagnosis of SBP. The point estimates of sensitivity and specificity from each study are shown as solid circles. Error bars indicate 95% CIs. CI = confidence interval, SBP = spontaneous bacterial peritonitis.

FIGURE 6

Summary receiver operating characteristic curves summarize the overall diagnostic accuracy for procalcitonin assays. Each solid circle represents each study in the meta-analysis. Symbol size for each study is proportional to the study size.

FIGURE 7

Funnel graph for the evaluation of potential publication bias in procalcitonin assays. Symbol size for each study is proportional to the study size. The line in the center indicates the summary DOR. The Egger test for publication bias was not significant. DOR = diagnostic odds ratio.