IL19 and acne: The mean of IL-19 serum concentration of group of patients with mild acne vulgaris is 18.38 ± 9.59 pg/ml, that of group of patients with moderate acne vulgaris is 21.23 ± 11.99 pg/ml, and that of group of patients with severe acne vulgaris is 31.19 ± 20.36 pg/ml.