About Allergy and Immunology
Allergy and Immunology is the medical sub-specialty that focuses on evaluation, diagnosis, and management of allergic diseases and disorders of the immune system. When the immune system has an abnormal reaction to a substance, it produces allergic antibodies, resulting in allergies and asthma. When the immune system malfunctions, it produces antibodies that attack and destroy healthy tissue in the body, resulting in autoimmune disorders. Immunodeficiency (or immune deficiency) is a state in which the immune system's ability to fight infectious disease is compromised or entirely absent.
An allergy is a hypersensitivity to substances in the environment. Allergies affect one out of four people in the United States and are the fifth leading chronic disease among all ages. Allergies can affect anyone of any age or gender.
Symptoms of an allergic reaction include coughing, sneezing, watery and itchy eyes, and a runny nose. In some cases, it can also cause hives, rashes, and difficulty breathing. When severe, it can even lead to death.
Common allergies include:
- Environmental Allergies – An allergic response to airborne irritants such as pollen from trees, grasses, weeds, dust mites, animal dander, and mold.
- Food Allergies – Foods that most often trigger an allergic reaction include peanuts, tree nuts, milk, eggs, fish, and shellfish.
- Allergic Rhinitis – The two types of allergic rhinitis are seasonal allergic rhinitis (hay fever) and perennial allergic rhinitis, which occurs year-round. Seasonal allergic rhinitis is caused by outdoor allergens such as pollen. Perennial allergic rhinitis is caused by indoor allergens such as dust mites, pet dander, and mold.
- Skin Allergies – A rash or irritation of the skin that occurs in response to ingested foods or medications, or when an allergen touches your skin.
- Stinging Insect Allergies – This allergy is due to the venom in bee stings, ant bites, mosquito bites, etc.
- Drug Allergies – Allergic reaction is an unwanted side effect of medication. Reactions to antibiotics (penicillin, sulfa, etc.), non-steroidal antiinflammatory drugs (Motrin, Aleve, ibuprofen, Toradol, aspirin, etc.), contrast dye, and blood pressure medications (ACE-inhibitors and diuretics) range from a mild localized rash to serious effects on vital systems.
Anaphylaxis is a severe allergic reaction. The patient can have serious breathing difficulties, and can even lose consciousness and die if not treated quickly. The allergic reaction may involve the whole body. Anaphylaxis is a medical emergency and requires immediate medical treatment.
Symptoms of anaphylaxis are listed below:
- Swelling of the lining of the mouth, tongue, lips and throat; causing breathing difficulty.
- Urticaria (hives)
- Nausea and vomiting.
- Cold and clammy skin.
- Rapid heartbeat.
- Feeling faint or lightheaded.
- An unexpectedly abrupt feeling of intense anxiety or impending doom.
Asthma is a chronic (long-term) lung disease that inflames and narrows the airways. Asthma causes recurring periods of wheezing (a whistling sound when you breathe), chest tightness, shortness of breath, and coughing. The coughing often occurs at night or early in the morning, but an asthma attack can occur at any time.
An asthma attack can happen when you are exposed to "asthma triggers." Your triggers can be very different from those of someone else with asthma. Some of the most common triggers are tobacco smoke, dust mites, outdoor air pollution, strong smells (such as perfumes or cleaning products) pet dander, and mold.
Autoimmune disorders consist of a large group of diseases characterized by abnormal functioning of the immune system that causes your immune system to produce antibodies against your own tissues.
Examples of autoimmune (or immune related) disorders include:
Celiac disease (celiac sprue)
Systemic lupus erythematosus
Immunodeficiency disorders occur when the body's immune response is reduced or absent. They impair the immune system's ability to defend the body against foreign or abnormal cells that invade or attack it (such as bacteria, viruses, fungi, and cancer cells). As a result, unusual bacterial, viral or fungal infections, and rare cancers may develop. Some immunodeficiency disorders shorten life span. Others persist throughout life but do not affect life span, and a few resolve with or without treatment.
There are two types of immunodeficiency disorders:
- Congenital (primary): These disorders are present at birth and are usually hereditary. They typically become evident during infancy or childhood. There are more than 200 congenital immunodeficiency disorders. All are relatively rare.
- Acquired (secondary): These disorders develop later in life and often result from use of a drug or from another disorder, such as diabetes or human immunodeficiency virus (HIV) infection. They are more common than congenital immunodeficiency disorders.
Conditions that irritate, clog, or inflame your skin can cause symptoms such as redness, swelling, burning, and itching. Allergies, irritants, your genetic makeup, and certain diseases and immune system problems can cause dermatitis, hives, and other skin conditions.
Contact Dermatitis - Contact dermatitis is the term used for a rash or irritation of the skin that occurs when allergens touch your skin.
Eczema - The term eczema is broadly applied to a range of persistent skin conditions. Symptoms include dryness and recurring skin rashes that are characterized symptoms such as redness, swelling, itching and dryness, crusting, flaking, blistering, and cracking.
Pruritus – Pruritus, the medical term for "itchy skin", can be caused by any number of medical conditions from allergic reaction to systemic disease. Pruritus is not a disorder, but an indication of another problem.
Urticaria - Urticaria is the medical term for "hives", "welts", or "wheals". Characterized by a red, raised, itchy skin rash, it is sometimes triggered by an allergic reaction. When symptoms last less than six weeks, it is called acute urticaria. If symptoms of urticaria continue for more than six weeks it is called chronic urticaria.
Angioedema – Angioedema is similar to urticaria, but occurs deeper inside the skin. The swelling causes a burning sensation and typically occurs on the face and neck, fingers, toes, and in the genitals of males and females.