Evaluation of serum levels of IL-17, IL-20 AND IL-22 IN psoriatic patients from north india and their correlation with disease severity

Background: Convincing evidence suggests that Psoriasis is an inflammatory disease. Inflammatory response in psoriasis is mediated by over expression of proinflammatory cytokines produced by Th1 cells and relative under expression of Th2 cytokines. These cytokines induce chemokines and other effecter cells via production of IL-17, IL-20 and IL-22, thus play role in pathogenesis of Psoriasis. Objective: To correlate the serum level of IL-17, IL-20 and IL-22 with Psoriatic lesions and area affected with Psoriasis in North India. Patients and Methods: In this study we calculated serum levels of IL-17, IL-20 and IL-22 in 150 Psoriatic patients as well as 200 healthy controls. Further the level of cytokines was assessed by ELISA and correlated to disease severity measured by psoriasis area severity index (PASI) score. Results: The present study includes 150 Psoriatic patients (101 males and 49 females) of age group 18-75 years with mean and SD of age 39.55±14.65. The mean and SD of PASI was 15.10±11.96, ranged from 0.3-49.2. Observations revealed that serum level of IL-17 in psoriatic patients was found 143.78±33.99 pg/ml. Serum level of IL-22 among studied psoriatic patient was found 74.42±24.08 pg/ml and serum level of IL-20 was found to be 96.73±26.52 pg/ml. Limitations: Follow-up of psoriatic patients was not done. A larger sample size would have validated the results further. Conclusion: Results show significant difference in serum level of IL-17, IL-20 and IL-22 in Psoriatic patients as compared to healthy controls. As it was observed that serum cytokines were significantly elevated in psoriatic patients, thus present study correlated the elevated level of serum cytokines with disease severity.