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It is well recognized that the hospital may not be a safe place, and not just for patients with PI. Hospital-borne infections are a major issue for all patients, but can be more severe for patients with a compromised immune system. I don't understand the logic of requiring infusions in the hospital when home infusions, IV or SC, may save money and help reduce the risk of hospital borne infection.

The hospital can help by putting the patient in a private room in the infusion suite or at least having a separate area for routine infusions versus those who are in the clinic with infections. The use of masks by patients is probably not necessary but might make sense if the infusions are done in a large room with many patients. Most infections are transmitted hand-to-mouth. Thus, it is important for the infusion nurse to wash between patients, even if just running back and forth to check pumps or do vital signs. At a minimum, the use of an antibacterial hand wash will help

It is equally important for the patient and parents to wash, especially before eating. How many children play with the common toys in the clinic and then eat lunch or snacks? You don't have to be as paranoid as Monk on television, but some common sense precautions can reduce the risk of getting infections in the hospital as well as other places when you travel.

The key elements in diagnosing CVID are low levels of immunoglobulins in at least two classes, usually IgG and IgA, and decreased or absent specific antibody responses to immunization or infection. There are other, related, antibody defects, such as specific antibody deficiency with normal immunoglobulins, but a diagnosis of CVID implies that the levels are low for the patient's age. The decision to treat is not as straightforward.

A doctor would be more likely to treat a patient who had multiple infections that had not responded to conventional therapy. There must have been something that triggered the diagnostic evaluation for immune deficiency. Usually, that would be recurrent infections, but occasionally it might be done for arthritis, inflammatory bowel disease, swollen lymph nodes, or even a malignancy. Not all of these symptoms respond to IVIG. In addition, CVID, or Common Variable Immune Deficiency, is, well, variable. Some patients may have borderline low immunoglobulin levels or reduced but not absent antibody responses. It can evolve over time, with a borderline abnormality at initial diagnosis but a more severe defect a couple of years later. Thus, an initial decision to continue treatment with antibiotics might change to start IVIG once the defect is more severe.

There is no specific level that would trigger an automatic decision to start IVIG, though, in general, the lower the level the more likely it would be that IVIG would be started. Thus, it would be uncommon not to start IVIG in a boy with Bruton's agammaglobulinemia and an IgG level of 70 mg/dl, whereas a patient with CVID and an IgG level of 500 mg/dl might not be treated even though that level is still abnormal. Children normally have lower immunoglobulin levels than adults, so it is important that age appropriate normal ranges are used.

If you do not understand why your doctor has decided not to treat your daughter you need to ask, and keep asking until you understand. No one is born understanding the immune system, and you have earned a right to an education. You can learn more about CVID and other immune defects by visiting web sites from patient groups such as the Immune Deficiency Foundation or the Jeffrey Modell Foundation.

There have not been any documented complications from the long-term administration of immune globulin. The first patients started in the early 1950's and some continue to receive treatment. Obviously, there are side effects from IVIG, such as fever and chills, hives, headaches, and allergic reactions, as well as more serious, though rare complications such as reduced kidney function or blood clots. However, the risk of these complications does not increase over time.¹

Some patients receiving subcutaneous gammaglobulin complain of some thickening of the skin or scarring at the sites, but that seems to be the exception.

Gammaglobulin products have improved over the years, and lead to fewer side effects than the early products that were available during the first three decades of use.¹ Still, treatments should be done with attention to dose and rates of infusion to minimize the risk of any side effects.

There is no set of tests that is recommended for all patients. Most immunologists would check a blood count and check liver and kidney function at least once or twice a year. It is also recommended to check an IgG level at least once a year, but it might be important to check it more often if a patient continues to have infections or might have abnormal losses such as through chronic diarrhea. The routine use of x-rays is more controversial. It is reasonable to check a chest x-ray once a year, but if a patient has lung damage it might be necessary to check more often. In fact, some studies have shown that lung damage might progress even without obvious infections, yet not show up on a chest x-ray. CT or MRI scans might be necessary to detect the progression. Progressive lung damage might be an indication for more intensive IVIG therapy, even if there are not any overt lung infections, as well as a more extensive evaluation for other causes of lung damage such as gastro-esophageal reflux and aspiration.

There are many forms of PI, so one answer is not correct for everyone, but since most people refer to patients with antibody deficiency, we can focus on that set of immune defects. The primary protection from the MMR vaccine is due to the antibody response, even though it also induces some T cell immunity. Thus, if a child with PI cannot make antibodies, they won't benefit from the MMR. The good news is that IVIG contains enough antibodies from healthy donors to protect someone from getting measles, mumps, or rubella. It also protects against exposure to chicken pox. IVIG is not sufficient to treat any of these virus infections if given after the infection begins, so it must be present at or shortly after exposure. In general the MMR vaccine is safe, but it should not be given to patients with PI who have significant T cell defects.

Common Variable Immunodeficiency (CVID) is not one disease, but a collection of several genetic diseases that have different types of immune defects. These diseases share common manifestations: at least two of the major immunoglobulins (IgG, IgA, and IgM) are significantly low for age, and antibody responses to common bacterial and viral infections or immunizations are poor.

If a child truly has CVID, then it is very unlikely that he or she will "outgrow" it and no longer need to receive infusions of gammaglobulin. However, very young children, under 2 or 3 years of age, may have delayed maturation of the immune system and be low for age, but able to "catch up." This is known as Transient Hypogammaglobulinemia of Infancy.

All children start with IgG from their mothers, but they have low IgA and IgM. They have to start making their own immunoglobulins after birth. The normal values for children are developed for the "average" child, but just as some children walk or talk at different ages, some children take longer to develop their immune system. Most of these children have low immunoglobulins, but can make antibodies well, and so they do not need to get infusions of IVIG. But, some do have poor responses to infections and immunizations and get an unusual number or severity of infections. These children are sometimes diagnosed as CVID and treated. If the correct diagnosis is Transient Hypogammaglobulinemia then these children may "outgrow" their disease and no longer need to be treated.

It is sometimes difficult to distinguish between the two diagnoses in very young children, so it is appropriate to reevaluate children as they get older, say 5 or 6 years of age. Talk to your immunologist to see if reevaluation is appropriate for your child.

People with PI get infections more often and take longer to recover. However, when they are not experiencing an infection, they are likely to look like anyone else. There are many variables which affect whether a person with PI looks sick, including the type of PI and the type of therapy they are using. So a person with PI who's receiving therapy and who's not experiencing many infections may look healthy.

You can’t catch a primary immune disease. Primary Immune Deficiency (PI) is inherited, which means a person is born with altered genes received from his or her parents. People with PI are vulnerable to viral and bacterial infections, such as colds or sinusitis, and may “give” such an infection to another person, but the PI condition is not contagious. It is important to distinguish this from HIV infection, or AIDS, where the viral infection does destroy the T cells and therefore results in an immune deficiency. Because there is so much public awareness and concern about AIDS, it is important to explain the difference so that people will not be worried that they can become sick.