The Clinical Value Of The Neutrophil-to-lymphocyte Ratio In The Diagnosis Of Adult-onset Still's Disease

Objective: The neutrophil-to-lymphocyte ratio(NLR)is the proportion of absolute neutrophil count to lymphocytes on routine complete blood count tests and has been studied as a simple marker of the systemic inflammatory response.This study was performed to evaluate the clinical value of NLR in the diagnosis of AOSD,so as to diagnose early and correctly.Methods: This retrospective study was performed in the First Hosptial of Jilin University between September 2014 and September 2017.Clinical data of 117 patients with “fever of unknown origin” were collected and analysed.Afer excluson,59 AOSD patients,58 non-AOSD patients and 98 healthy subjects as controls were enrolled to the current study.All clinical data were based on electronic medical records.Clinical characteristics,including age and gender were evaluated.Laboratory tests,including ferritin,ESR,CRP,the NLR,PLR LMR were evaluated.Statistical analyses were performed using SPSS software.Results: Compared with health controls,the NLR and PLR were remarkably higher in both AOSD and non-AOSD patients,while LMR was significantly lower(all P<0.001).AOSD patients showed higher NLRs,lower MLRs,and higher levels of ferritin,ESR,and CRP than non-AOSD patients(all P<0.001).When we compared PLR levels by AOSD and non-AOSD patients,those levels did not differ between 2 groups(13.40±11.12 vs 5.01±5.13,P=0.54).The NLR levels were not different between female and male in patients with AOSD,P=0.465.In receiver operating characteristic(ROC)curve analysis of the NLR for diagnosis of AOSD,the area under the curve(AUC)was highest at 0.839(95% CI=0.759–0.919)with a cutoff value of 6.95.The cutoff value showed the greatest sensitivity(79.7%),specificity(84.6%),and AUC value(0.839)as a diagnostic tool for AOSD.At the same time,combining Yamaguchi criterion and the levels of NLR to diagnose AOSD will have a high rate of specificity with 98.8%.Related parameters such as such as gender,NLR,ESR,and CRP detected by univariate logistic regression analysis were statistically related to AOSD.Multivariate logistic regression was performed to show the risk of AOSD patients in women was 3.821 times than that of men and the risk of having AOSD was increased by 1.199 times for every unit increase in NLR.Conclusions: The NLR is a valuable marker for the diagnosis of AOSD in the patients with fever of unkown origin.