title: The diagnostic value of neutrophil: lymphocyte ratio in adults with suspected acute appendicitis.
abstract: OBJECTIVE
  To validate the use of neutrophil : lymphocyte ratio (NLR) in diagnosing appendicitis.
  
  
  METHODS
  Patients who had had an appendicectomy but where no post-operative histology was available and those under the age of 16, or those who had undergone an interval appendicectomy in a non-emergency setting were excluded from this study. The NLR, WCC, CRP and NLR x CRP were recorded for all patients and these were then compared to their postoperative histology. To determine whether NLR on admission to hospital was an independent predictor of positive appendicitis histology, a multiple logistic regression model was constructed, using factors with a p-value of 0.1 or less in univariate analysis.
  
  
  RESULTS
  One thousand one hundred and seventeen (1117) patients who underwent an appendicectomy between January 2005 and January 2009 were included in this study. The median age was 34 years, with a range of 16-94 years. The area under the ROC curve for NLR was 0.836, compared to 0.779 for WCC, 0.732 for CRP and 0.815 for NLR x CRP.
  
  
  CONCLUSIONS
  The results of this study suggest that as an adjunct to clinical examination, NLR appears to be of greater diagnostic accuracy than either WCC or CRP alone.
authors.affiliation: Department of General Surgery, Cambridge University Hospitals NHS Foundation Trust. sheraz_markar@hotmail.com
authors.forename: S R
authors.initials: SR
authors.lastname: Markar
authors.forename: A
authors.initials: A
authors.lastname: Karthikesalingam
authors.forename: A
authors.initials: A
authors.lastname: Falzon
authors.forename: Y
authors.initials: Y
authors.lastname: Kan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001062:Appendectomy; D001064:Appendicitis / Q000097:blood* / Q000175:diagnosis* / Q000601:surgery; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D009504:Neutrophils; D011237:Predictive Value of Tests; D012372:ROC Curve; D055815:Young Adult
chemical_list: D002097:C-Reactive Protein