Specific Antibody Deficiency (SAD) Investigation

           In class we have been discussing the structure and function of the different classes of anitbodies we find in our immune system. Our body contains five classes on immunoglobulins which include IgA, IgG, IgD, IgE, and IgM. Out of these five IgG is the immunoglobulin who has the main role in protection against infections, as it protects us from bacteria and viruses. SAD is a disorder in which a person has normal levels of all immunoglobulins except IgG. Due to the fact that IgG having a main role in protecting against infection, it is common for patients with SAD to experience recurrent infections. Particularly it has been found that IgG acts against the sugar coat of illnesses such as Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenza. This is because IgG produces molecules against the pathogens that cause upper and lower respiratory infections.

            However, as crucial as IgG is to our immune system, our bodies are equipped with other components that also help in fighting off infections such as T cells, complements proteins, other WBCs and IgA. This explains why some patients diagnosed with SAD rarely get sick. This means that their other components are working well together and compensating for the deficiency of IgG. In general, the infections suffered by patients with SAD are not as severe as those suffered by patients who have combined deficiencies of IgG, IgA and IgM. For example diseases such as X-linked Agammaglobulinemia (XLA) or Common Variable Immune Deficiency. Although, often patients with SAD will come to the physician’s office with a single severe pneumonia or other infection.

          Although recurrent infections in the ears, sinuses, bronchi or lungs is usually a pretty good indicator of SAD, to diagnose precisely diagnose one must measure the total amount of immunoglobulins. Treatment for SAD usually can be treated with antibiotics, unless the infection has taken a severe course. In this case Ig replacement therapy is considered. Children are more likely to outgrow SAD through close monitoring and immunizations such as pneumococcal vaccines. If diagnosed as a teenager or adult it is less likely that the deficiency will be resolved on its own. In both scenarios close monitoring of the Ig levels is crucial.

 

 

 

"Specific Antibody Deficiency." Immune Deficiency Foundation. N.p., 2013.

        Web. 19 Oct. 2016. <http://primaryimmune.org/about-primary-

         immunodeficiencies/specific-disease-types/specific-antibody-         deficiency/>.