What is Anaphylactic Shock?

What is Anaphylactic Shock?

What is Anaphylactic Shock?

Anaphylaxis or anaphylactic shock is the term used to describe a sudden, severe, and often life-threatening allergic reaction involving multiple organ systems.  It is triggered by exposure to an allergen, usually a protein that the immune system considers as ‘”foreign” substance.  These proteins are usually present in certain foods, insect venoms, natural rubber products, medications, etc.  Though the reaction can occur after the first exposure, it generally takes a few exposures before the sensitizing antibody (e.g., Immunoglobulin E or IgE) titers cross a threshold level to initiate the reaction.

Theoretically any food can trigger a reaction in a sensitized individual, but the most common foods implicated in these reactions are peanuts, tree nuts, fish, shellfish, and eggs.  More recently, several instances of anaphylaxis caused by mammalian meats have been described in the literature. The first of these mammalian meat allergies was diagnosed in Virginia.  The bite of the lone star tick has been determined to cause this unusual condition and the allergists at Black & Kletz Allergy have seen and manage quite a few cases of this disorder.  An unusual feature of the anaphylaxis that occurs in mammalian meat allergy is that the anaphylaxis is usually delayed many hours after ingesting a mammalian meat as opposed to occurring quickly after ingestion which tends to occur with more typical food allergy reactions.

Among anaphylaxis to insects, honey bees, yellow jackets, white-faced hornets, yellow-faced hornets, and wasps are the usual culprits in the Washington, DC, Northern Virginia, and Maryland metropolitan area.  Anaphylaxis to fire ants is also a fairly common problem, however, most of these cases occur in the southern U.S. where fire ants are much more prevalent.

Anaphylactic reactions to medications are not uncommon and penicillins are the most common group of drugs to cause this type of severe reaction. Latex is the usual natural rubber product that is responsible for a large number of anaphylactic reactions as well as local reactions.  Latex gloves, condoms, dental dams, and balloons are some of the common items that often cause these reactions.

Signs and symptoms of the reaction usually appear within a few minutes after exposure and progress rapidly unless promptly recognized and treated.  Generalized itching (i.e., pruritus), flushing, hives (i.e., urticaria), swelling of the soft tissues (i.e., angioedema), wheezing, and shortness of breath are the common manifestations of anaphylaxis.  In more severe cases, the reaction may progress to nausea, vomiting, and drop in blood pressure (i.e., hypotension) causing cold and clammy skin which is often referred to as “shock.”  In addition, individuals may experience dizziness, disorientation, and loss of consciousness.

These symptoms are mediated by certain chemicals such as histamine which are released from the body’s mast cells as a result of IgE antibodies adversely interacting with the offending protein.  Early recognition of the signs and symptoms of anaphylaxis and prompt injection of epinephrine (i.e., adrenaline) can arrest the progress of the reaction and can be life-saving.  It is important for individuals with an increased risk of anaphylaxis to be prescribed and taught how and when to use an epinephrine self-injectable device (e.g., EpiPen, Auvi-Q, Adrenaclick) for emergency treatment and know to then go immediately to the closest emergency room.  The board certified allergy doctors at Black & Kletz Allergy have over 50 years’ experience in the diagnosis and management of anaphylaxis.