Antibody response to pneumococcal vaccination as a function of preimmunization titer.

Background: The interpretation of an adequate response to the unconjugated 23-valent pneumococcal vaccine for serotypes having high preimmunization titers remains challenging.

Objectives: We sought to determine whether high preimmunization titers preclude a 4-fold or greater response to vaccination. Moreover, we sought to determine the effect of the following covariates on this response: absolute preimmunization titer value, age, sex, serum IgG level, and serum IgG subclasses.

Clinical manifestations of food allergy: differentiating true allergy from food intolerance.

Food allergy is an abnormal immunologic reaction to food proteins. In this article, we differentiate food allergy from food intolerance and other conditions that may mimic food allergy. We describe clinical presentations of food allergy, outline a practical approach for evaluating patients with suspected food allergy, and discuss recommendations for management.