He was 12 years old when he ate his last meal. He did not know what anaphylactic shock was, but that’s what happened to him after traces of peanut in his food triggered a severe immune response.
Explore this issueApril/May 2009
His lungs were transplanted into a 42-year-old female with no prior history of peanut allergy. Seven months after the transplant, she suffered anaphylactic shock after eating a peanut butter cookie. She survived but suffered a second anaphylactic shock later that same year. After doctors questioned her, she recalled that the first episode had occurred four days after the transplant. Skin prick testing confirmed sensitization to peanuts. This kind of peanut allergy transfer from donor to recipient has also been described after liver transplantation.
Food allergies happen when a person’s immune system reacts to proteins in what he or she has eaten. In an attempt to protect the body, the immune system produces antibodies to that food. Those antibodies then cause mast cells—allergy cells in the body—to release chemicals, one of which is histamine, into the bloodstream. Histamine then acts on a person’s eyes, nose, throat, lungs, skin, or gastrointestinal tract, causing the symptoms of the allergic reaction.
According to the Food Allergy & Anaphylaxis Network (FAAN), one in 25 adults and one in 17 children have food allergies. Statistics like these indicate a need for reliable manufacturing practices such as testing and proper labeling.
Once an allergic reaction begins—a true food allergy, not a food intolerance—it is impossible to predict how severe it will become. It has been observed that an allergy that persists into teenage or adult life is less likely to disappear.
Www.webmd.com explains how the timing and location of an allergic reaction depend on the complex process of digestion. For example, a person who is allergic to a particular food may first experience itching or tingling in the mouth. After the food is digested, abdominal symptoms such as vomiting, diarrhea, or pain may ensue. When the food allergens enter and travel in the bloodstream, they can cause a drop in blood pressure. Allergens reaching the skin can trigger hives or eczema; when they reach the lungs, they may cause asthma. These symptoms may occur within minutes, or they may take hours to start.
People who have a food allergy may also experience anaphylaxis, a severe allergic reaction that causes swelling of the mouth, throat, and airways leading to the lungs that results in an inability to breathe. In addition, anaphylaxis causes a dangerous drop in blood pressure, which can not only make someone dizzy or pass out but may quickly lead to shock and death. There is no medication in any form that can be taken before eating a certain food that will reliably prevent an allergic reaction to that food. The main treatment, injectable epinephrine, must be carried at all times.
The Food Allergy and Anaphylaxis Management Act (FAAMA), passed by the United States House of Representatives in April 2008, is an important bill that calls for creation of a uniform guidance document to help schools manage food allergies. The bill will direct the Secretary of Health and Human Services to develop a voluntary policy for schools to implement measures to prevent exposure to food allergens and to ensure a prompt response if a child suffers a potentially fatal anaphylactic reaction. The Senate Committee on Health, Education, Labor, and Pensions is to consider the bill within the coming months.
Some schools have responded to the dangers posed by food allergies by banning the major allergy-causing foods, creating, for example, so-called peanut-free zones. Unfortunately, until the peanut police can pat down every child and helpful laws can take effect, schools are limited in their ability to protect students.