These Questions & Answers originally appeared in the IDF monthly e-newsletter, Primary Immune Tribune. Click here to subscribe.
Question: My doctor is going to test me for Specific Antibody Deficiency. I had a doctor test this many years ago, and the results were “borderline.” What is the specific criteria for determining the results of the Pneumovax-23 challenge test, also known as the Pneumococcal polysaccharide vaccine (PPSV)? What is the amount of expected increase in serotype titer levels?
Answer: This is an area of varying opinion. There may not be general agreement on the criteria for determining an adequate response from PPSV vaccine challenge. Most clinical immunologists use a criteria of 2 fold over baseline, if the baseline is already over 1.3 mcg/ml, and/or generating a protective level of specific antibody over 1.3 mcg/ml. Another criteria is that following immunization with the vaccine, 50-70% of the 23 serotypes should be protective (>1.3 mcg/ml) or a 2 fold increase.
Another thing to consider is those who do produce a protective response to the vaccine but the antibody levels drop off rather quickly within 6 months. This is called memory phenotype Specific Antibody Deficiency. For further information, please consult your medical advisor or use Ask IDF in your IDF My Account to contact us.
Question: I have CVID, and I am considering a trip to Nepal. Would vaccinations be helpful?
Answer: It is important to discuss this with your healthcare provider to determine which vaccines you can get. If any of the recommended vaccines are “live,” then these usually are not recommended in those with an antibody deficiency. You can receive “non-live” or “killed” vaccines as these will not hurt you, but this does not necessarily mean you will be protected, as you may not produce a response to the vaccines.
Whether you are on immunoglobulin replacement therapy plays a role, as well. If you are getting Ig, the antibodies in the product you infuse technically protect you.
You can go to the CDC’s website to see what vaccines are recommended by destination. Click here.
For additional travel tips from IDF, click here.
These answers should not be used as a substitute for professional medical advice. In all cases, patients and caregivers should consult their healthcare providers. Each patient’s condition and treatment are unique.