Anaphylaxis

Anaphylaxis is a hypersensitive reaction due to contact through allergens. These allergens induce an immediate immune response that is life threatening in most occasions. Anaphylactic reactions produce various clinical symptoms such as urticaria, respiratory congestion and gastrointestinal disturbances. Anaphylactic response is caused by certain type of compounds which may include proteins, pollen, venom, hormones and also some food extracts. The immunoglobulin E or IgE is responsible for the onset of anaphylactic reaction when exposed to an allergen.

Mechanism of anaphylactic reaction

A series of reactions take place in the body when anaphylaxis is triggered. The IgE which has a half-life of two days, binds to the fragment crystallizable or FC receptor part of the basophils and mast cells. This process is activated when the person comes in contact with an allergen which in turn mediates cellular de granulation and their release of biogenic amines such as histamine and serotonin. The effects of these biogenic amines may include the smooth muscles which generally constrict at the bronchiolar region and broncho capillary venules. It also causes the arteriole dilation.

Anaphylactic responses are of different types and are associated with allergen sources of different kinds such as pollen, food, insects and also some drugs. It happens because of the antigen contact to which the patient had been previously exposed. This type of antigen is also called an allergen. Systemic anaphylaxis is a serious condition in which the mast cells of the connective tissue become activated resulting in dangerous effects such as airway obstruction, swelling of the epiglottis and ultimately suffocation. Systemic anaphylaxis proceeds into another condition called anaphylactic shock which happens because of suffocation induced by the respective allergen. In addition to these, anaphylaxis may also result because of extreme physical exercise. This condition is also called exercise induced urticaria. Allergies to food like eggs and milk are common among infants. Other than these, underlying conditions such as hay fever, asthma and eczema may also induce anaphylaxis if untreated.

Anaphylactic shock is widely reported in people after consuming foods such as peanuts and Brazil nuts. Such food products induce the anaphylactic reaction in an instant causing severe discomfort and sometimes death. Many people also experience anaphylactic reactions because of penicillin administration. Some reactions of anaphylaxis also include excess production of mucous in the mouth, nose and throat. Atopic patients are highly susceptible to anaphylaxis. Patients having an underlying atopic condition produce high amount of IgE antibodies and hence they must be monitored carefully.

Diagnosis of Anaphylaxis

Anaphylactic reaction is diagnosed based on clinical symptoms such as skin rash (insect bites), hoarse voice, chest congestion, breathing difficulty, diarrhea, vomiting and abdominal cramps. Identification of the source is the predominant factor in the diagnosis of anaphylactic reactions. Thorough examination of the cause with immediate life saving measures must be done. Anaphylaxis can be fatal if not managed properly.

Anaphylaxis Treatment

Avoid foods that induce the condition. In the case of anaphylactic reaction, medical attention must be sought immediately. Oral medications such as Benadryl or diphenhydramine are given. EpiPen or injectable epinephrine is the drug of choice to control the anaphylactic reaction. Intravenous antihistamine drugs and oral steroids are given for a period of time to prevent the reoccurrence of the anaphylactic reactions.