HIVES
Hives (Urticaria) is a common skin condition characterized by red bumps or welts that itch. Individual lesions usually last for less than 24 hours. Hives are categorized as either acute (lasting less than 6 weeks) and chronic (lasting longer than 6 weeks). Acute hives may be related to an external trigger (foods, insect stings, medication reactions, etc.) whereas chronic haves are thought to be more autoimmune in nature. Depending on your history our physicians may suggest environmental, food, or drug allergy testing. Certain labs (bloodwork) may be indicated in some circumstances. Treatment usually involves a stepwise approach including histamine blockade (H1, H2 blockers), biologic therapy (Xolair), or use of immunosuppressants.
Possible Causes of Hives
- INFECTIOUS DISEASE – viral infections (most common cause of acute urticaria), hepatitis, infectious mononucleosis, bacterial, parasitic or fungal infections
- MEDICATIONS – penicillin, other antibiotics, aspirin, insulin, vaccines, allergy injections, morphine, demerol, codeine, etc
- ENVIRONMENTAL ALLERGENS – grass, animal dander or saliva, insect stings, etc
- FOODS – eggs, milk, wheat, soy, peanuts, treenuts, fish, shellfish and other foods
- AUTOIMMUNE or NONINFECTIOUS CAUSES – autoimmune hives (most common cause of chronic hives), collagen vascular disease, malignancy, thyroid disease, hormonal changes
- PHYSICAL AGENTS – cold, heat, sunlight, pressure, vibratory, exercise
- PSYCHOLOGICAL FACTORS – Stress, anxiety
Evaluation and Treatment
Acute hives not associated with angioedema or respiratory distress is usually self limited and evaluation may include testing for possible triggers.
Chronic hives require an extensive evaluation with history, physical exam, allergy testing and laboratory testing for the immune system, liver, kidney, thyroid and collagen vascular diseases. Special tests will be sent for anti-thyroid antibodies and high affinity IgE receptor (FceR1) antibody to look for autoimmune hives. Age appropriate cancer screening is recommended. 55% of patients will not have an identifiable trigger for their hives.
