The primary immunodeficiency community often identifies with zebras. This is based on an old saying students hear in medical school: “When you hear hoof beats, think horses, not zebras” They’re taught to focus on the likeliest possibilities when making a diagnosis, not the unusual ones. For patients with immune deficiencies, doctors need to look for zebras.
By the time I was diagnosed with Common Variable Immune Deficiency, (CVID), I’d been contending with relentless diarrhea (Collagenous Colitis), for seven years, and had lost my left lung, thanks to Coccidioidomycosis, (Valley Fever) and some other nasty fungi. Unfortunately, it is not uncommon for a diagnosis of CVID to take 7-8 years.
When blood tests revealed I was low in antibodies: IgG and IgA, and that I had lazy T-cells, I was finally diagnosed and started getting a four-hour infusion of Intravenous Immunoglobulin, (IVIG), every four weeks. IVIG contains the pooled immunoglobulin G (IgG) immunoglobulins from the plasma more than 1000 blood donors. Because it’s a treatment I’ll need for the rest of my life, I have an IV catheter that has been surgically placed under the skin on my chest called a Port-a-Cath. It’s a central IV line, meaning it goes straight to my heart. The port is a small reservoir, about the size of a thimble, with a silicone septum that gets pierced with a needle when I get my IVIG infusions. When not in use, it looks like a little misplaced third breast!
WHAT ARE PRIMARY IMMUNODEFICIENCIES?
Primary immunodeficiency diseases (PIDDs) are a group of more than 300 rare, genetic disorders that impair the immune system. Without a functional immune system people with PIDD are subject to severe infections, some of which can increase the risk of developing cancer. Some can be fatal. PIDDs may be diagnosed during infancy, childhood, or adulthood.
Here is a list of a few PIDDs:
Common Variable Immunodeficiency (CVID)
Chronic Granulomatous Disease (CGD)
DiGeorge Syndrome (DGS)
Selective IgA Deficiency
Severe Combined Immunodeficiency (SCID)
X-Linked Agammaglobulinemia (XLA)
While all the diseases differ, they all share one common feature: they are all caused by a defect in one of the functions of the body’s normal immune system. Because one of the most important functions of the normal immune system is to protect us against infection, patients with PIDD commonly have an increased susceptibility to infection.
Patients with PIDD experience infections of the skin, sinuses, throat, ears, lungs, brain, spinal cord, urinary and intestinal tracts. Because of their increased vulnerability to infection, the infections are often chronic and severe. Because of their susceptibility, patients with PIDD have recurring health problems and often developing serious and debilitating illnesses. However, with proper medical care, they can live relatively normal lives.
Common Variable Immune Deficiency is a disease that affects the immune system. A person with CVID is highly susceptible to infection from foreign invaders such as bacteria and viruses, and often develops recurrent infections in the lungs, sinuses and ears. Pneumonia is common in people with CVID. These recurrent infections often lead to chronic lung disease. It is also common for CVID patients to have chronic infection and inflammation in their intestinal, resulting in diarrhea and weight loss.
People with CVID have a higher risk of developing certain types of cancer, including a cancer of immune system cells called non-Hodgkin lymphoma and stomach cancer.
Symptoms of the disease can start anytime from childhood to adulthood. CVID is often diagnosed when a person is in their twenties or thirties. The life expectancy of individuals with CVID varies depending on the severity and frequency of illnesses they experience. Most people with CVID live into adulthood.
Treatment for CVID requires immunoglobulin replacement therapy, which replaces Ig subtypes lacking in the patient. Treatment is given at frequent intervals for life, and helps reduce bacterial infections and boost immune function. Before therapy begins, plasma donations are tested for known blood-borne pathogens, then pooled and processed to obtain concentrated IgG samples. Infusions can be administered in three different forms: intravenously (IVIG): subcutaneously (SCIG), and intramuscularly (IMIG).
The administration of IVIG requires the insertion of a cannula or needle in a vein, usually in the arms or hands. Because highly concentrated product is used, IVIG infusions take place every 3 to 4 weeks. Subcutaneous infusions slowly release the Ig serum underneath the skin, again through a needle, and takes place every week. Intramuscular infusions are no longer widely used, as they can be painful and are more likely to cause reactions.
People often experience adverse side effects to immunoglobulin infusions, including:
- swelling at the insertion site (common in SCIG)
- nausea (common in IVIG)
- fatigue (common in IVIG)
- muscle aches and pain, or joint pain
- fever (common in IVIG and rare in SCIG)
- hives (rare)
- thrombotic events (rare)
- aseptic meningitis (rare, more common in people with SLE)
- anaphylactic shock (very rare)
In addition to Ig replacement therapy, treatment may also involve immune suppressants, to control autoimmune symptoms of the disease, and high dose steroids like corticosteroids. In some cases, antibiotics are used to fight chronic lung disease resulting from CVID. The outlook for people varies greatly depending on their level of lung and other organ damage prior to diagnosis and treatment.
For more information about all the PIDD’s, check out these links: