Biology of Humans 6th Edition by Judith Goodenough,Betty McGuire

Exercise 7

In this chapter, we learned about allergies. We saw that following first exposure to an allergen, plasma cells produce IgG antibodies that are specific for that allergen, which bind either basophils or mast cells. This binding causes the cells to release histamine. In turn, histamine produces the redness and swelling we identify as allergy symptoms. We also considered anaphylactic shock, an extreme, potentially fatal allergic response. In anaphylactic shock, blood collects in capillaries, causing extremely low blood pressure. Air tubules constrict and make breathing difficult. Anaphylactic shock occurs within minutes after a subsequent exposure to the triggering allergen. You can read the entire study here: J. Ching et al., "Peanut and fish allergy due to platelet transfusion in a child," Canadian Medical Association Journal [April 7, 2015] 187(6); doi:10.1503/cmaj.141407 According to a report in the Canadian Medical Association Journal, children can develop allergies after blood transfusions. The report presents the case of an 8-year-old boy who was given a blood transfusion as part of treatment for brain cancer. Less than 2 weeks after the transfusion, the boy, who had no known food allergies previously, went into anaphylactic shock after eating salmon. The emergency room personnel noted that his blood pressure was low. The doctors treated the boy with antihistamines and advised him to carry an EpiPen (an epinephrine injector). Four days later, the boy ate a chocolate peanut butter cup. His lips swelled and he vomited. An allergy test revealed that the boy was allergic to fish and nuts. The boy's oncologist called the center that supplied the blood for transfusion and learned that the donor had food allergies to fish, shellfish, and nuts. The doctor concluded that IgG antibodies in the donor's plasma triggered food allergies in the recipient. Within a few months, the allergies ended, because the boy's blood no longer contained IgG antibodies.
Based on the evidence cited in the case report, do you think that the doctor's conclusion about the cause of the allergies is valid Why or why not