Side Effect: Low Blood Immunoglobulin (Low IgG Levels)

What is Low Blood Immunoglobulin (Low IgG Levels)?

Hypogammaglobulinemia, or low levels of immunoglobulins (IgG, IgA, IgM) in the blood is a condition where the body does not product enough “B lymphocyte antibodies.” Specifically, IgG antibodies are necessary for fighting off infections. When patients have low IgG levels, they may have recurrent bacterial infections, sinus infections, and pneumonia.

What does Low Blood Immunoglobulin (Low IgG Levels) look like?

Low IgG levels are characterized by a decrease in level of immunoglobulins in the blood, which can be detected by blood tests. In some cases, clinicians might order genetic tests to identify underlying causes of the condition. Typically, low IgG levels are not felt by patients, but symptoms involve frequent and recurring infections. These include fatigue, plus:

• Respiratory infections; sinus infections, bronchitis, pneumonia
• Ear infections
• Gastrointestinal infections: diarrhea
• Skin infections

Who gets Low Blood Immunoglobulin (Low IgG Levels)?

An IgG deficiency (or low levels) can affect anyone, but certain factors can increase the risk. When patients are immunodeficient (primary or secondary), this can significantly increase their risk. Primary immunodeficiency is when patients are born with genetic conditions that affect their immune system. Secondary immunodeficiencies happens when other conditions or treatments, like chemotherapy, are given. Radiation therapy and bone marrow transplant are two other examples in patients with cancer that increase risk. This is because these therapies can lead to bone marrow suppression and decrease production of immunoglobulins, as well as destroy the immune cells in the body. Certain types of cancer (ex: lymphomas) can directly affect the immune system and increase risk as well.

How to prevent Low Blood Immunoglobulin (Low IgG Levels)

In patients with cancer, prevention can be difficult as a lot of therapies can affect the immune system. Some steps to minimize the risk of infections are:

• Good hygiene: regular handwashing and avoiding close contact with people who are sick
• Vaccinations: staying up-to-date with recommended vaccines
• Healthy lifestyle: balanced diet, regular walking or exercise as able, adequate sleep, and managing stress

Additionally, patients with cancer will have immune function monitored during treatment. Use of growth factors to stimulate production of immune cells is sometimes utilized. In some patients, preventing infections involves administration of immunoglobulin replacement therapy. This is an intravenous (IV) infusion to replace the missing or deficient immunoglobulins in the blood.

How to treat Low Blood Immunoglobulin (Low IgG Levels)

Similar to prevention, low IgG levels can be treated through replacing immunoglobulins. This involves regular infusions to boost the body’s immune function. The most common strategies for low IgG level treatment are listed below:

• Antibiotics (used to treat bacterial infections):
  
  • Amoxicillin (Amoxil®)
  • Sulfamethoxazole/trimethoprim (Bactrim®)
  • Azithromycin (Zithromax®)
  • Clarithromycin (Biaxin®)
  • Ciprofloxacin (Cipro®)
  • Levofloxacin (Levaquin®)
• Immunoglobulin replacement therapy
  
  • Intravenous immunoglobulin (IVIG) given through a vein (IV)
    
    • Gammagard®
    • Gamunex-C®
    • Privigen®
    • Octagam®
    • Flebogamma®
  • Subcutaneous immunoglobulin injected under the skin
    
    • Hizentra®
    • Cuvitru®
    • HyQvia®