One of the most common signs of primary immunodeficiency is an increased susceptibility to infections.

CNN: Primary immunodeficiency

There are more than 70 types of primary immunodeficiency disorders, and signs and symptoms differ depending on the particular type of disorder you have.

CNN: Primary immunodeficiency

Baxter, one of several companies that make it, says it takes 130 plasma donations to make enough to treat one patient with primary immunodeficiency for a year.

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