Primary and Secondary Immunodeficiency
Primary and Secondary Immunodeficiency
The immune system is composed of many cells types, proteins and chemical messengers that work to fight infections. Some individuals are born with a genetic variation that affects a component of their immune system which manifests as recurrent, severe and/or unusual infections. This is referred to as primary immunodeficiency. There are over 400 different primary immunodeficiencies that have been identified and it is estimated that they affect about 1 in 10,000 individuals. Because the immune system is not functioning properly, in some individuals this can be complicated by either autoimmunity (where the immune system attacks various parts of the body) and/or an increased risk of developing malignancy.
Secondary immunodeficiencies refer to other conditions that cause immune suppression and present similarly to primary immunodeficiencies. Secondary immunodeficiencies can result from the use of immunosuppressive medications for other conditions, malnutrition, certain malignancies and HIV/AIDS.
Diagnosis
Primary and secondary immunodeficiencies are diagnosed based on a reported history of recurrent/severe infections as well as certain blood tests that assess various aspects and function of the immune system. In some cases, genetic testing is performed to look for genetic variations that are known to cause disease. Listed below are 10 warning signs for possible immunodeficiency in adults as adapted from https://immunodeficiency.ca:
1. Two or more new ear infections within 1 year
2. Two or more new sinus infections within 1 year, in the absence of allergy
3. One pneumonia per year for more than 1 year
4. Chronic diarrhea with weight loss
5. Recurrent viral infections (colds, herpes, warts, condyloma)
6. Recurrent need for intravenous antibiotics to clear infections
7. Recurrent, deep abscesses of the skin or internal organs
8. Persistent thrush or fungal infection on skin or elsewhere
9. Infection with normally harmless tuberculosis-like bacteria
10. A family history of Primary Immunodeficiency
Treatment
The specific treatment for primary and secondary immunodeficiencies depends on what part of the immune system is affected and the severity of the immunodeficiency. Treatment options vary and can include close observation, long term use of antimicrobials on a regular basis to prevent infection, and/or administration of antibodies (immunoglobulins) from healthy donors which are given either intravenously or subcutaneously. A bone marrow transplant is where the immune system of the affected individual is replaced with the immune system from a healthy donor and is generally only done in children with certain primary immunodeficiencies.