Diagnostic And Clinical Significance Of Serum Levels Of D-Lactate And Diamine Oxidase In Patients With Crohn’s Disease

Background:Crohn’s disease(CD)is a chronic intestinal inflammatory disease whose etiology remains unknown.Currently,there is no cure for Crohn’s disease.The goal of medical treatment is to control and maintain the intestinal inflammation within the range of remission stage.The endoscopy examination is mostly used to make diagnosis,to assess the severity of disease and to evaluate the recovery of intestinal mucosa after treatment.However,endoscopic procedure is costly,invasive,time-consuming and associated with risk of multiple complications.An ideal laboratory marker that can detect disease activity and monitor the effectiveness of treatment,and also provide a prognostic value for relapse or recurrence of the disease is clinically desirable.Two biomarkers have been extensively studied in CD: C reactive protein(CRP)and erythrocyte sedimentation rate(ESR).It has been shown that these two markers correlate significantly with endoscopic lesions,risk of relapse and with the response to therapy.However,the sensitivity and specificity of these two markers are far from being satisfactory.When CD patients suffer from a systemic infection or autoimmune connective tissue diseases,the two biomarkers are not sufficiently accurate to detect the disease activity,which leads to late treatment due to inability to make a timely diagnosis.Development of a set of new monitoring biomarkers that are more sensitive and specific is clinically important.D-Lactate(D-LA)and diamine oxidase(DAO)are two indicators that reflect the intestinal barrier function and may be related to the activity of the disease.Objective:To explore the application value of D-Lactate and diamine oxidase in the judgment of Crohn’s disease activity.Methods:A total of 59 CD patients were enrolled in this study.Enzyme-Linked Immunosorbent Assay(ELISA)was used to quantitatively detect the content of D-Lactate and the diamine oxidase levels in sera obtained from patients and 28 healthy controls.The correlation between these two biomarkers and disease activity scores was assessed.In addition,the ROC curve was used to evaluate the diagnostic accuracy of these two biomarkers.Results:The levels of D-LA in the serum of CD patients in the active stage and remission stage were(16.08±4.80)mg/L and(11.16±3.17)mg/L,respectively,and the difference was statistically significant(t=4.67,P<0.001).DAO levels were significantly higher in patients with the active stage compared to controls.The levels of D-LA and DAO in CD patients were positively correlated with the disease activity(r=0.68,0.53,P<0.05).The area under the curve ROC(AUC)when CD activity was diagnosed with D-LA and DAO alone was 0.815 and 0.748,respectively.The diagnostic efficacy of the two biomarkers was not significantly different from that of erythrocyte sedimentation(ESR)and hypersensitive c reactive protein(CRP)(P>0.05).However,area under the curve was 0.861(0.746,0.937)when the diagnosis was performed using a combination of D-LA,DAO,CRP,and ESR,which was significantly higher than when CRP or ESR were tested(P<0.05).Conclusions:D-LA and DAO have a good prognostic value for CD activity.Rational combined use of biomarkers can significantly improve the diagnostic efficiency.