A patient is immunocompromised when one of the parts of their immune system is not functioning for any of a number of reasons. Immunocompromised patients are very susceptible to infection and are vulnerable to the rapid spread of diseases such as cancer. There can be several reasons why a patient might be immunocompromised, but in any event it is the result of a lack of white blood cells or the inability of a patient to produce antibodies. Some conditions that result in a patient being immunocompromised are: AIDS - from the destruction of T-cells by the HIV virus. See also Immunosuppresants