title: Plateletcrit: a sensitive biomarker for evaluating disease activity in Crohn's disease with low hs-CRP.
abstract: OBJECTIVE
  This study aimed to investigate whether PLT indices could act as non-invasive biomarkers for active Crohn's disease (CD).
  
  
  METHODS
  Altogether 130 CD patients and 130 age- and gender-matched healthy volunteers were retrospectively enrolled in the study. CD patients were further divided into patients with active disease (Crohn's disease activity index [CDAI] >150) and in remission. PLT indices including PLT count, mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR) and plateletcrit (PCT) were detected. High-sensitivity C-reactive protein (hs-CRP) and erythrocyte sedimentation rate (ESR) levels were also determined.
  
  
  RESULTS
  In active CD, PLT and PCT levels were notably higher but P-LCR and PDW levels were lower than those in healthy controls and patients in remission. PLT, PDW, P-LCR and PCT were significantly correlated with CDAI (P < 0.05). The receiver operating characteristic (ROC) curve showed that with a cut-off value of 0.28%, PCT achieved a sensitivity of 67% and a specificity of 63% for detecting active CD, with the area under ROC curve (AUROC) of 0.67, which was inferior to hs-CRP and ESR. For patients with active disease who had hs-CRP levels lower than 10.0 mg/L, PCT turned out to be the best index for monitoring disease activity (sensitivity 71%, specificity 85%, AUROC 0.77, P = 0.02).
  
  
  CONCLUSIONS
  PCT may act as a specific and sensitive biomarker for determining active CD, especially in patients with an hs-CRP level lower than 10.0 mg/L.
authors.affiliation: Department of Gastroenterology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Tang
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Zhi
authors.forename: Hui Min
authors.initials: HM
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Huang Wei
authors.initials: HW
authors.lastname: Chen
authors.forename: Qing Fan
authors.initials: QF
authors.lastname: Yang
authors.forename: Zhe Zhao
authors.initials: ZZ
authors.lastname: Liang
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000473:pathology / Q000502:physiology*; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D048429:Cell Size; D003424:Crohn Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D010976:Platelet Count; D012074:Remission Induction; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein
keywords: Crohn disease; biological markers; blood platelets; disease activity; inflammatory bowel diseases; plateletcrit