Thank you for your inquiry.
Unfortunately, the issue brought up by your inquiry is controversial. According to the best of my knowledge, different opinions exist regarding whether the response to pneumococcal vaccination in a patient with relatively protective pre-vaccination titers and normal immunoglobulins can determine the need for immunoglobulin replacement therapy. In the final analysis, clinical judgment is used to make the decision as to whether or not to administer immunoglobulin in such cases.
As you can see in Summary Statement 30 copied below, from a recent practice parameter(1), one can make a diagnosis of specific antibody deficiency based upon a poor response to pneumococcal immunization in spite of the fact that both the response to immunization with protein antigens and total immunoglobulin levels are normal. Although this does not guarantee that protective levels to pneumococcus would be normal pre-immunization, it clearly states that hypogammaglobulinemia is not a sine qua non for the diagnosis of specific antibody deficiency.
Thank you again for your inquiry and we hope this response is helpful to you.
(1) The Journal of Allergy and Clinical Immunology
Volume 130, Issue 3, Supplement , Pages S1-S24, September 2012
Use and interpretation of diagnostic vaccination in primary immunodeficiency: A working group report of the Basic and Clinical Immunology Interest Section of the American Academy of Allergy, Asthma & Immunology
"Summary "Statement 30: A diagnosis of specific antibody deficiency (SAD) can be made if the response to PPV23 is deficient but the responses to protein antigens (eg, tetanus toxoid or diphtheria toxoid), conjugate vaccines (Haemophilus influenzae type b, PCV7, or PCV13), or both are intact and total immunoglobulin levels are normal. (III C)"
Phil Lieberman, M.D.