Nitroblue tetrazolium test is used for-

This test is done to screen for chronic granulomatous disease. This disorder is passed down in families. In people who have this disease, ceain immune cells do not help protect the body from infections. People who have frequent infections in the bones, skin, joints, lungs, and other pas of the body may have this test donThe chemical NBT is added to the white blood cells in the lab. The cells are then examined under a microscope to see if the chemical has made them turn blue.