The psoriasis area and severity index (PASI) score sheet was adopted according to Fredriksson and Pettersson and Marks et al. [15, 16] for all patients as an indication of degree of severity. In mild cases, the extent of the disease does not exceed 10, while in severe cases, the extent of the disease is more than 30 based on the PASI score [17] . Informed consent was obtained after complete description of the study from each participant, according to the guidelines of the local ethical committee of the National Research Center.