Immune Deficiencies

What is an immune deficiency?

An immune deficiency is characterized by the body’s inability to fight infections. Patients with an immune deficiency have recurrent infections, prolonged infections, and sometimes require hospitalization to treat severe infections. The most common sites of infection are the lungs, sinuses, ears, and skin.

What are the causes of immune deficiencies?

There are many types of immune deficiencies, some of which are associated with other disorders, such as autoimmune disorders, gastrointestinal disorders, and cancers.  Some immune deficiencies are due to a genetic mutation that has been identified, but in many others the cause is unknown.

How is an immune deficiency diagnosed?

A diagnosis of an immune deficiency is usually made based on a complete medical history and physical examination.  In addition, multiple blood tests may be ordered to confirm the diagnosis, including antibody levels, antibody function, cell counts, and immune cell function.  Patients often receive a vaccine and the body’s response to the vaccine is measured in the next 4-6 weeks. Some patients may also need imaging of the lungs or sinuses.

Treatment

The treatment depends on the type of immune deficiency that is diagnosed.  In some types of immune deficiency where the body does not make enough antibodies or does not make functional antibodies, we can replace those antibodies.  This is called immunoglobulin replacement, and is often abbreviated as IVIG (intravenous immunoglobulin) or SCIG (subcutaneous immunoglobulin).  The risks, benefits, and burdens of immunoglobulin replacement will be discussed with the patient and family before deciding on this type of treatment.

Management also includes prompt treatment of infections. Rarely, antibiotics are prescribed prophylactically to prevent an infection.  The patient should not receive any live viral vaccinations (such as the one given for measles, mumps, rubella (MMR) and chickenpox (varicella)), because the patient could develop the disease for which the vaccine was given.

For specific types of severe immune deficiencies, bone marrow or hematopoietic stem cell transplantation is the best treatment option.  This involves taking cells that are normally found in the bone marrow (the soft, spongy tissue found inside the bones that is responsible for the development of blood cells), and giving them back either to the patient or to another person.  The goal of transplantation is to provide a complete immune system, and therefore the patient no longer has significant problems fighting infections.