Serum IL-22 as a Novel Non-Invasive Biomarker in Diagnosis and Assessment of Activity in Ulcerative Colitis Patients

Abstract Background Ulcerative colitis (UC) is a multifactorial disease of unknown etiology. Mucosal healing is an important predictor of the course of disease and has therefore become the aim of UC treatment. Repeated endoscopies to identify mucosal inflammation are expensive. Interleukin (IL)22 is a member of the IL-10 family of cytokines that was recently discovered to be mainly produced by both adaptive and innate immune cells. Aim of the Work The aim of this study was to evaluate the role of serum IL-22 as a novel noninvasive biomarker in diagnosis and assessment of activity in ulcerative colitis patients. Patients and Methods This was a case control study that was conducted on 55 subjects at Ain shams university hospitals inpatients and outpatients settings throughout 6 months. Subjects were divided into 2 groups: Group (A): that included 40 patients with ulcerative colitis: 20 patients in clinical, laboratory and endoscopic remission and 20 patients in clinical, laboratory and endoscopic activity and Group (B) that included15 healthy controls. Results Statistical analysis revealed the following: Age ranges from 32_77 years and the mean age was 36 years in this study. Males were affected slightly more than females in our study. NO statistically significant difference found between three groups regarding HB, Total bilirubin, Creatinine and Urea, and there was statistically significant difference found between three groups regarding Platelets and AST, and there was highly statistically significant difference found between three groups regarding Wbcs, ALT, ESR, CRP and Albumin. For Interleukin 22, there was highly statistically significant difference found between three groups. There was highly statistically significant difference found between IL-22 (Pg/ml) and Colonoscopy, and there was statistically significant difference found between IL-22 (Pg/ml) and Histological examination, and there was no statistically significant difference found between IL-22 (Pg/ml) and Extend. Receiver operating characteristic curve (ROC) showed that the best cut off point of IL-22 (Pg/ml) to detect Patient group was found > 4.7 with sensitivity of 90.0%, specificity of 100%, PPV of 100.0%, NPV of 78.9% and total accuracy of 0.95%. Conclusion It is concluded that IL22 is an important marker of ulcerative colitis as it shows significant correlation with endoscopic and histological features, so it can be used instead of these interventions to achieve high satisfaction to patients.