Influence of irradiation on resistance to infection.

The following tissue damage has been described after whole body X-radiation: destruction of the intestinal mucosal lining with ulceration and hemorrhage, destruction of lymphoid tissue and of bone marrow, severe leucopenia and thrombocytopenia, and damage to capillary endothelium (1, 2). The observations on germfree animals by Gordon and Scruggs at the Lobound Institute have shown that if the radiation damage is sufficiently severe death will ensue in the absence of complicating infection (3). Germfree rats, however, survive lethal doses of X-radiation significantly longer than conventional animals. Animals and men do not live in a germfree environment, and it is now well established that infection as a consequence of weakened defenses is a very frequent lethal complication of whole body X-radiation in the LD50 to LDIoo range of dosage. In atomic bomb casualties (1), after the second week, heavily infected ulcerated lesions in the skin, mucous membranes, and respiratory tract