TNF and psoriatic arthritis: Novel studies using tumor-necrosis factor alpha (TNF-alpha) inhibitors have shown great promise for recalcitrant inflammatory conditions such as plaque psoriasis, Crohn’s disease, hidradenitis suppurativa, (i.e., inflammatory skin disease that affects apocrine gland bearing skin in axillae, groin, etc.)psoriatic arthritis, and rheumatoid arthritis in various medical settings.7