Inflammatory abnormality of the skin Unusual infection by anatomical site Unusual skin infection 2018-12-09T12:47:37Z Unusual skin infection Recurrent or unusual skin and mucous membrane infections are characteristic of T-cell deficiencies, phagocyte defects, and inborn errors of IL-17 immunity. Increased susceptibility to infection of the skin, nails, or mucous membranes, as manifested by recurrent or severe cutaneous or mucosal infection, or by skin or mucous membrane infection caused by an atypical or opportunistic organism.