Comparison of the diagnostic value of procalcitonin and C-reactive protein after hematopoietic stem cell transplantation: a systematic review and meta-analysis

Objective To conduct a systematic review and meta-analysis of the performance of the procalcitonin (PCT) diagnostic test for identifying infectious complications after hematopoietic stem cell transplantation (HSCT). Methods We searched EMBASE, MEDLINE, the Cochrane database, and reference lists of relevant articles, with no language restrictions, through December 2011. We selected original articles that reported diagnostic performance of PCT alone or compared with other biomarkers for identifying serious infections in HSCT recipients. We quantitatively evaluated test accuracy parameters with the use of forest plots, hierarchical summary receiver operating characteristic curves, and bivariate random effect models. Results We found 6 qualifying studies (studying 1344 episodes of suspected infection with confirmed infectious episodes) from 3 countries. These 6 studies examined both PCT and C-reactive protein (CRP) test performance. Bivariate pooled sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios were 0.66 (95% confidence interval [CI] 0.60-0.72), 0.72 (95% CI 0.65-0.79), 2.39 (95% CI 1.84- 3.09), and 0.47 (95% CI 0.39-0.57) for PCT, and 0.80 (95% CI 0.54-0.93), 0.73 (95% CI 0.56-0.86), 3.00 (95% CI 1.86-4.84), and 0.27 (95% CI 0.11-0.65) for CRP. In terms of area under the curve (AUC), CRP was superior to PCT in detecting infectious complications, with an AUC of 0.82 for CRP versus an AUC of 0.69 for PCT. Conclusion The pooled accuracy estimates of 6 different studies indicated only a moderate rule-out diagnostic value of both PCT and CRP in discriminating infection from other inflammatory complications following allogeneic HSCT.