A Case Of Urticaria (Hives)

A 45 Year old woman presents to her doctor complaining of itching and red patches on her skin of the legs, arms and abdomen. It first appeared 2 weeks back and has been increasing since then. She recalls having similar symptoms in the past at least 4 times . She relates it to start whenever she drinks citrus fruit juice. She was prescribed antihistamines and her symptoms gradually improved. She was advised to avoid food that trigger the allergy.

Case Discussion:

Hives also known as Urticaria is a skin reaction that presents as a red, raised, itchy skin rash. It appears and fades repeatedly. It usually happens due to an allergy.
Chronic hives is defined when the symptoms last more than six weeks or recur over months or years.

Pathophysiology; Whenever there is an allergic reaction triggered by a substance-allergen , body releases histamine . Histamine causes tiny blood vessels t leak fluid which accumulates in the skin causing the rash and swelling.

Causes : Females and young adults are more prone to utricaria. Each individual may develop symptoms due to a particular allergen to which his/her body responds and produces histamine.
Some of the common causes include:

• Medicines
• Insect bites
• Scratching
• Temperature changes
• Stress
• Exercise
• Sunlight
• Particular food

Clinical features: Hives appear suddenly as swollen, red bumps, patches or welts on the skin. Hives usually itch but sometimes patients can complain of burning or stinging sensation. 

Some patients may identify the allergen that triggered the rash. 

The rash affects almost any part of the body including face, arms, hands, legs and toes. In most cases a welt will disappear after a few hours only to be replaced by new ones. These welts vary in size and shape. Urticaria itself is not life threatening but it does cause discomfort and interferes with sleep due to itching. Patients daily activities might be effected if it is recurring frequently. 

In severe cases there is swelling of the lips or cheeks and may progress to angioedema which might be life threatening.

Diagnosis: 
In acute cases (symptoms lasting < 6 weeks) generally no laboratory studies are indicated.
For chronic or recurrent cases basic laboratory work like CBC, ESR, Thyroid stimulating hormone (TSH) and antinuclear antibody (ANA) is indicated.

Management: The main stay of therapy for both acute and chronic urticaria is patient education, avoiding triggers and using antihistamines.
Sometimes chronic utricaria becomes difficult to treat and causes considerable discomfort to the patient. The first line of treatment is usually a second generation anti histamine like cetrizine or loratidine which causes less sedation as compared to first generation anti histamines.
Systemic glucocorticoids can be used for episodes of severe disease but should not be used for long term because of side effects.
If patient does not respond to anti histamines the second step is to either increase the dose of current anti histamine or to add another anti histamine or a leukotrine receptor antagonist like monteluekast.
Patient still does not responding are considered as refractory and may need anti inflammatory medications like dapsone or salphasalazine or immunosuppresants like cyclosporine.