Abnormal delayed hypersensitivity skin test UMLS:C1833172 This is an immune function test measuring the presence of activated T cells that recognize a certain substance. Delay in cutaneous immune reaction to specific antigens mediated not by antibodies but by cells. The delayed hypersensitivity test is an immune function test measuring the presence of activated T cells that recognize a specific antigen and is performed by injecting a small amount of the antigen into the skin. The area of the injection is examined 48-72 hours thereafter. HP:0002963 Abnormal T cell physiology