Question

Peanuts are one of the most common causes of food allergy in the United States and Europe. They are also a leading cause of food-induced anaphylaxis and death, which usually follow inadvertent exposures. Allergy to peanuts is an IgE-mediated, mast-cell-dependent, immediate-hypersensitivity reaction. There are numerous reports of the transfer of allergen-specific IgE-mediated hypersensitivity by bone marrow transplantation. We report a case of peanut allergy transmitted through combined liver-and-kidney transplantation.
Hypersensitivities can be described as immediate, subacute, or delayed. How do these sensitivities diff er? What evidence did the doctors use to determine that the peanut allergy was an immediate hypersensitivity?

Answer 1

As evident by the wording being "immediate, subacute, and delayed", types of hypersensitivities differ based on how quickly the side-effects manifest in someone exposed to them.

• Immediate hypersensitivity has an almost immediate side-effect when exposed to someone.  
• Subacute hypersensitivity is something that manifests some time after its exposure. This type of hypersensitivity is commonly found with slow exposure, and can be treated even months after its first exposure.
• Delayed hypersensitivity is something that manifests itself years after exposure, and not all at once.

Peanut allergies (both when tested on people to see what effects it will have in a lab and when broken down chemically and mathematically) is something whose side effects manifest almost immediately whether it be minor itching or even mass swelling. Even without major testing, one could deduce with almost certainty that in almost all cases, there is an immediate hypersensitivity to peanut allergies when provoked.