A 3 year old child presents with a history of repeated sinopulmonary infections caused by encapsulated organisms. Which of the following is most likely to be deficient in this case?
Deficiency of IgG2 results in recurrent sinopulmonary infections with encapsulated organisms. Deficiency of IgG1 - Bacterial infections (Diptheria, tetanus) Deficiency of IgG3 - Viral infections Deficiency of IgG4 - Parasitic infections IgG is the only maternal immunoglobulin that is normally transpoed across the placenta and provides natural passive immunity to the newborn. Maximum placental transfer - IgG1 Minimum placental transfer - IgG2 Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition
IgG4
IgG3
IgG2
IgG1
Immunology