IL4 and Henoch-Schoenlein purpura: Furthermore, B. hominis has already been known to cause cutaneous hypersensitivity reactions by alternating the immune system via activation of specific Th2 immune cells producing interleukins including IL-3, IL-4, IL-5, and IL-13, and some immunological disorders such as urticaria, Hashimoto's thyroiditis, and Henoch-Schönlein purpura have been mentioned to be associated with B. hominis infection [11, 14, 15].