Procalcitonin could be a reliable marker in differential diagnosis of post-implantation syndrome and infection after percutaneous endovascular aortic repair. 
Thoracic endovascular aortic repair (TEVAR) is an emerging treatment modality, which has been rapidly embraced by clinicians treating thoracic aortic disease.  However, the clinical manifestations of systemic inflammatory response after TEVAR as post-implantation syndrome (PIS) resemble the perioperative infection.  This study aimed to evaluate changes and diagnostic value of procalcitonin (PCT) and other traditional inflammatory markers for infections after TEVAR.  We conducted a prospective clinical study that enrolled 162 consecutive aortic dissection cases, who underwent TEVAR in our institution between July 2011 and November 2012.  The PCT, C-response protein (CRP), erythrocyte sedimentation rate (ESR) and blood routine examination were monitored before the operation and on days 1, 2, 3 and 5 after the operation.  The diagnosis of infection was confirmed by the infection control committee with reference to Hospital Acquired Infection Diagnostic Criteria Assessment, released by the Ministry of Health of the People's Republic of China.  Post endovascular repair of thoracic aorta, PCT changes significantly at different time points (χ(2) = 13.225, P = 0.021), without significant difference between the PIS group and the control group (0.24 ± 0.04 vs.0.26 ± 0.10, P = 0.804).  PCT values were significantly higher in the first day after TEVAR than the preoperative levels (0.18 ± 0.03 vs. 0.11 ± 0.02, P < 0.001).  Compared with PIS patients, the level of PCT, CRP, White blood cell (WBC) and neutrophil (NEU) in the infection patients elevated significantly (relatively χ(2) = 6.062, P = 0.048; χ(2) = 6.081, P = 0.048; χ(2) = 11.030, P = 0.004; χ(2) = 14.632, P = 0.001).  According to the ROC analysis, the PCT levels in the first day after TEVAR (AUC = 0.785, P = 0.012) had better predictive values of infection than WBC, NEU CRP and ESR (AUC = 0.720, P = 0.040; AUC = 0.715, P = 0.045; AUC = 0.663, P = 0.274; AUC = 0.502, P = 0.991).  The best predictive index was the changes of PCT between preoperative and postoperative (PCT), which possess AUC as 0.803 (P = 0.014).  And PCT = 0.055 could be considered as an infection diagnosis cutoff value with a sensitivity of 83.3% and specificity 69.0%.  PCT provides better diagnostic value of infection compared with other inflammatory markers.  The potential applications of PCT in differential diagnosis of PIS and infection after percutaneous TEVAR deserve further studies.