Recurrent Chest Infections – Need to Test Immunoglobulin Levels
Background: Recurrent chest infections in those with COPD can cause coughing, chest congestion, shortness of breath, and “feeling sick all of the time.” These symptoms may improve with courses of antibiotics and prednisone, but may recur weeks after these medications are stopped.
One possible cause for repeated chest infections is a low level of antibodies.
Plasma cells, which are part of the body’s immune system, makes antibodies to fight off bacteria, viruses, and other invaders that could harm overall health.
The body makes several types of immunoglobulin antibodies called A, G, and M. They are abbreviated as IgA, IgG, and IgM. IgA is found at high levels in saliva, tears, and nasal secretions. IgG is found in blood and in tissue, while IgM is found in blood.
In some individuals, plasma cells do not produce normal levels of antibodies. This medical condition is called common variable immunodeficiency (abbreviated CVID). It is estimated that CVID occurs in one out of 50,000 individuals in North America.
Case Report: I recently saw a 69 year old female in my practice who was referred for repeated episodes of pneumonia. She reports five different times she was sick with pneumonia in the past 11 months. Main symptoms are cough which may or may not be productive of mucus, more shortness of breath, feeling tired, and low grade fever. Recent x-rays of the chest showed shadows in the right lower lung area. For each episode her primary care physician prescribed an antibiotic and higher doses of prednisone.
She also has severe COPD based on results of breathing tests. She smoked one and one-half packs of cigarettes per day for 35 years, but quit 9 years ago. She did not report any heartburn symptoms to suggest possible acid reflux.
As part of her evaluation, I ordered blood tests to measure levels of immunoglobulins. Her IgG level was below normal, while IgA and IgM levels were in the normal range. I made the diagnosis of common variable immunodeficiency and ordered: a CT scan of the chest to look for bronchiectasis; and replacement therapy with IVIG (immunoglobulin G).
Discussion: CVID was reviewed recently in the November-December 2016 issue of the Journal of Allergy and Clinical Immunology: In Practice (volume 4, pages 1039-1052). Usually, the person has recurrent sinus and/or chest infections. In the lungs, these repeated infections can cause thickening of the walls of breathing tubes and damage air sacs which creates a reservoir for bacteria (bronchiectasis) as shown in the figure below.
To diagnose CVID, your health care provider should measure levels of immunoglobulins (IgA, IgG, and IgM) in blood.
Replacement therapy is available if a person has a low level of IgG. The goal is to increase blood levels of IgG to normal to prevent future sinus and respiratory infections. Treatment is given intravenously (through an arm vein) every 4 weeks. This can be done at home or in an infusion center at the hospital. Studies confirm that IgG replacement reduces infections in those with CVID.
Figure C (bottom right) shows bronchiectasis with mucus inside the breathing tube and thickening of the wall.
If the person also has bronchiectasis, it is important to obtain a sample of sputum to identify the specific type of infection. Antibiotic therapy may be necessary for weeks to months.
CT scan of the chest shows cystic changes in the lungs due to bronchiectasis.