Scleritis (inflammation of sclera) is a strong indication of the underlying medical problem. It can be due to fungal, viral or parasitic infection, trauma, exposure to chemicals, poisonous gases or due to post-surgical complications.
Mast cells are granulated cells typically found in connective tissue. These cells mediate immune responses to foreign particles. In particular, they release large amounts of histamine and enzymes in response to antigen recognition.
Histamine is a substance that is released from specialized cells called mast cells when they are activated, often as part of an allergic immune response. This test measures the amount of histamine in the blood or urine. Mast cells are large tissue cells found throughout the body. They are present mainly in the skin, the lining of the intestine and air passages, and the bone marrow. Mast cells are part of the body's normal response to injury as well as allergic (hypersensitivity) responses. They contain granules that store a number of chemicals, including histamine and tryptase, which are released when mast cells become activated.