Specimen Collection Manual and Test Catalog

1 mL aliquot of serum; minimum 0.2 mL.

Allow to clot. Centrifuge 10 minutes at 3000 rpm.

Refrigerated (preferred). Room temperature or frozen specimen also acceptable.

Room Temperature: 7 days. Refrigerated: 14 days. Frozen: 90 days.

Stability limits exceeded.

Evaluation of the response to pneumococcal vaccination is best accomplished by comparing pre-vaccination and post-vaccination antibody levels. A 2- to 4-fold increase in type-specific antibodies measured 4-6 weeks after vaccination is expected in immunocompetent adults. The number of serotypes for which a 2- to 4-fold increase is observed varies greatly among individuals; a consensus panel has suggested that individuals older than 5 years should respond to at least approximately 70% of pneumococcal serotypes. Adults > 65 years old may exhibit a smaller (< 2-fold) increase in type-specific antibody levels.

Serotype designations are American nomenclature, with Danish nomenclature in parentheses. Studies from the 1980s using radioimmunoassay suggested that vaccine-induced S. pneumoniae type-specific antibody levels of approximately 2.0 mcg/mL were protective against invasive pneumococcal disease. Newer methods (ELISA and multiplexed immunoassay) incorporating an adsorption step to remove cross-reactive antibodies yield results that are comparable to each other, but are lower than those obtained with the original radioimmunoassay. Rigorous studies of protective antibody levels as determined by the newer methods have not been performed. In addition to antibody quantity, protection also depends on antibody avidity and opsonophagocytic activity.

Serotypes 1, 3, 4, 5, 8, 9 (9N), 12 (12F), 14, 19 (19F), 23 (23F), 26 (6B), 51 (7F), 56 (18C), 68 (9V).

Streptococcus pneumoniae IgG Ab (14 Serotypes)., PN14, Quest test code 19564

The MAID procedure measures IgG antibodies recognizing 14 type-specific pneumococcal polysaccharide antigens included in the polyvalent vaccine (1, 3, 4, 5, 8, 9, 12, 14, 19, 23, 26, 51, 56, and 68). A 2- to 4-fold increase in type-specific antibodies measured 4-6 weeks after vaccination is expected in immunocompetent adults. The number of serotypes for which a 2- to 4-fold increase is observed varies greatly among individuals; a consensus panel has suggested that individuals older than 5 years should respond to at least approximately 70% of pneumococcal serotypes. Adults > 65 years old may exhibit a smaller (< 2-fold) increase in type-specific antibody levels.