Serum levels of 25-hydroxyvitamin D and IL17A and their association with acne severity in patients with severe and very severe acne vulgaris

Background Vitamin D deficiency and interleukin-17 (IL17) excess production have been detected in many inflammatory skin diseases. Acne vulgaris is a well-known inflammatory skin disease for which numerous treatment guidelines have been published, with limited success in several situations. Objective To evaluate the association between 25-hydroxyvitamin D [25 (OH) D] and IL17 levels from the patients' serum and acne vulgaris. To determine the therapeutic effect of vitamin D supplementation on severe acne. Patients and methods This case-control study was conducted on 30 patients with severe and very severe acne vulgaris. The severity of the disease was determined by Global acne grading system (GAGS). Moreover, 15 controls were recruited. Serum levels of 25 (OH) D and IL17A were measured at the baseline in all studied participants. After that, the patients with acne with detected vitamin D hypovitaminosis were given an oral dose of 4000 IU cholecalciferol daily for 3 months, and in this selected group, serum 25 (OH) D and IL17A levels along with GAGS score were measured again at the end of the treatment. Results The mean serum concentration of 25 (OH) D and IL17A in patients with severe acne was statistically different from the controls. Acne severity was negatively correlated with the vitamin D serum level and positively correlated with the IL17A serum level. After supplementation, significant improvement of both the median GAGS score and IL17A serum level was found. Conclusion Vitamin D deficiency might be related to the severity of acne vulgaris, and its supplementation may help ameliorate inflammatory lesions of severe acne through its immunomodulatory effect.