What is IMMUNODEFICIENCY-HYPOGAMMAGLOBULINEMIA?

 

Hypogammaglobulinemia is a form of immunodeficiency characterized by an abnormally low (deficient) concentration of gamma globulin (antibodies) in the blood and increased risk of infection.


What is an antibody deficiency?
An antibody deficiency is an immune defect that limits the body’s ability to identify “foreign invaders” or pathogens. In a fully functional immune system, specialized cells produce antibodies, which contribute to immune defenses by binding to the invading cell or particle, identifying it for destruction. In patients with antibody deficiency, these specialized proteins may be missing, not working properly, or too few in number to be effective.
Antibody deficiencies are classified as either “primary” or “secondary”. Primary antibody deficiencies arise spontaneously from genetic errors and other mechanisms that are only partially understood. Primary antibody deficiencies can either involve all antibodies or be limited to specific types of antibodies.


What are symptoms of antibody deficiency?
Antibody deficiencies limit the ability of the immune system to recognize and respond to infections caused by bacteria or viruses. A patient with an antibody deficiency will therefore tend to have both more frequent and more severe infections, and infections will often be of longer duration. These patients are also less capable of “developing immunity” and as a result, often suffer from chronic and recurring infections.


Can antibody deficiency be treated?
YES.  Until a few years ago, the only form of active treatment for antibody deficiency was antibiotic therapy, and the only form of prevention was isolation. For children, this meant staying out of school and out of contact with other children and adults.  Today, however, antibody replacement therapy is available. Because antibodies are also known as immunoglobulins, the terms immunoglobulin therapy and intravenous immunoglobulin  (IVIg) therapy are also commonly used.  IVIg therapy replaces the antibodies that are missing. The infusion contains antibodies purified from the blood donated by American volunteer donors. These antibodies remain in circulation for about a month, just as they do in the body normally.


What is IVIg and what disorders is it used to treat?
IVIg is used for three purposes; for patients who do not make antibodies or gammaglobulin, for patients with specific infections, and for patients with autoimmune and inflammatory diseases. Some individuals make no or too few antibodies and thus suffer from recurrent infections. Sometimes the antibody producing cells (B-cells) of individuals have an intrinsic inability to make antibodies; these are patients with Primary Immunodeficiency diseases, and many require life-long IVIg infusions. Examples include X-linked Agammaglobulinemia and Common Variable Immunodeficiency.
Blood tests are available to determine if a patient has low antibodies and needs IVIg. Since this treatment is often life-long and very expensive, careful testing needs to be done prior to starting IVIg. Indeed, like other drugs, IVIg may have side effects, so its use is reserved for just a few patients.
A second use of IVIg is in the treatment of certain infections in which antibiotic or antiviral therapy is ineffective. Examples include severe parvovirus infection and chronic viral meningitis. These patients do not require life-long IVIg and it can be discontinued after the infection is controlled.
A final use of IVIg is in certain inflammatory and immunologic diseases, often of unknown causes. Examples include an acute fever-causing childhood disease termed Kawasaki disease, and a blood disease termed immune thrombocytopenia, where the blood platelet levels are low and the patient develops bruising or bleeding.


Can Immunotherapy control seizures?
Author: L Seiden and A Krumholz
The occurrence of seizures in systemic immune-mediated disorders demonstrates that epilepsy can be related to immunologic disorders. This raises the issues of whether immune mechanisms may be important in other, more common forms of epilepsy and whether immunotherapy merits further consideration.  Immunoglobulin therapy was first reported to be effective in epilepsy in 1977, when children with epilepsy were given intramuscular IgG to treat recurrent upper respiratory tract infections. Improvements in seizure frequency and behavior were noted. Subsequently, 16 children with Lennox-Gastaut syndrome were treated with intravenous IgG (IVIg), and significant improvement was seen in 8 of them. Since that time, several additional clinical trials have been published with similar results, reporting significant improvement in about half of cases.
In 1994, the first double-blind, placebo-controlled trial of IVIg for the treatment of epilepsy was published. Three different dosages were evaluated in 61 patients with intractable epilepsy of various etiologies. Significant clinical improvement, defined as a reduction in seizures by at least 50% after 6 months, was reported in 52.5% of the IVIg group, compared to 27.8% of the placebo group, with a p value of .095. No dose relationship was identified.
There is emerging clinical evidence that IVIg may be of value in several refractory seizure conditions. The details regarding which patients and at what point of the illness it should be used need to be investigated further.


Is it possible to outgrow an immune deficiency?
The most common immune deficiency that seems to resolve with age is transient hypogammaglobulinemia. These patients develop symptoms at approximately six months of age. This is about the time when the maternal antibodies are diminishing in the infant's circulation. At this point, the infant may not be able to completely maintain his/her immunoglobulins on his/her own. Infections may occur during this time. Serum immunoglobulins in the infant may ultimately reach normal levels at four to six years of age. Other immunodeficiencies, such as IgA deficiency, may also resolve with age.  It is not possible to know if a child with hypogammaglobulinemia has a transient form unless the child outgrows the condition.

 

  • b-facebook
  • Twitter Round