Chronic urticaria is defined as wheals (hives), angioedema (swelling), or both that has been continuously or intermittently present for at least 6 weeks, in contrast to acute urticaria which is an episode of less than 6 weeks duration. This condition is common affecting about half a million Americans. It has recently been the subject of two review articles: Chronic Spontaneous Urticaria in the JAMA and Chronic Urticaria in the NEJM. The latter paper is appended below.
Chronic urticaria can have an extremely deleterious effect on the quality of life similar to that of coronary artery disease before definitive treatment. The disorder is more common in women and typically appears after age 40. “Chronic urticaria has been categorized on the basis of consensus criteria and guidelines as spontaneous urticaria (previously designated as chronic idiopathic urticaria), in which urticaria, angioedema, or both occur in an unprompted fashion, or as inducible urticaria (previously designated as physical urticaria), in which urticaria, angioedema, or both are elicited by factors such as cold, heat, or pressure.” [All quotations are taken from the paper below]
While some patients have an underlying systemic disease associated with their urticaria, most do not. The disorder is evanescent. There are periods when the disease flares with intervals without lesions. Patients often take photos of their hives with their cell phones to show the presence of the urticaria to their doctors when there are no hives. It is the pruritus (itchiness) that degrades the quality of life. The hives can appear on any part of the body and vary in severity from minor to life-altering. A photo of a severe flare is below.i
“Lesions range from a few millimeters to several centimeters in diameter and resolve in less than 24 hours, without residual bruising. In an often-cited series, two thirds of patients had both urticaria and angioedema, with the remaining one third having only one or the other.” If the rash persists for more than 24 hours another diagnosis should be considered such as cutaneous vasculitis.
There is a chronic inducible form of the disorder. The two commonest forms are dermatographia and cholinergic urticaria. “Dermatographia (“skin writing”) entails local histamine release generated by pressure applied to the skin.” This phenomenon is common. As much as 5% of the population may have it, though few require treatment. “Cholinergic urticaria, induced by active or passive heating of the body, is also common, accounting for approximately 5% of all cases of chronic urticaria and up to 30% of the inducible form.”
The use of anti-inflammatory non-steroidal anti-inflammatory ( NSAIDS) drugs may provoke severe attacks of this syndrome. If there is no change in the disorder following a month of the discontinuance of NSAIDS they can be restarted assuming there is a genuine clinical reason for their use.
The satisfactory treatment of this disorder is often difficult to achieve. The first line of such treatment is the use of second generation antihistamines. If this regimen fails the dose can be increased to four times the standard amount. If such treatment fails the monoclonal antibody omalizumab is FDA approved for both asthma and chronic urticaria. The recommended dosage for chronic hives is 150mg or 300mg every 4 weeks. The drug is very expensive and the patient in need of it may have a difficult time getting his insurance carrier to cover it. Cyclosporine is also said to be effective for this disorder, but its use is off-label.
A stepped approach to treatment is below – taken from the paper below. Steroids may be used for short-term control. As this treatment is associated with profound complications when used long-term it should only be employed on a limited basis. In general, a patient with the disorder should receive no more than 30 days of steroids in a year and no more than 10 days at a time.
If the hives are limited to a small surface area topical steroids followed by a layer of petroleum jelly may provide temporary relief. Such treatment can be repeated as needed. Obviously, it is not practicable when a large portion of the skin is affected.
Unfortunately, the cause of chronic urticaria remains unknown. Though not life threatening its negative effect on the quality of life can be profound. Much research into the immune mechanisms responsible for the disorder is ongoing. In the interim, symptomatic treatment as outlined here and in greater detail in the review below can provide relief for a substantial fraction of patients afflicted with this disorder.
Chronic Urticaria – Click to download
The reference to antihistamines prompts me to ask when they became available to primary-care physicians. As a boy I had chronic asthma, eczema, and allergies to ragweed and several forms of pollen. When I started school in the 1949-1950 academic year, our family doctor was reluctant to prescribe one called Phenergan because of its sedating effect. It wasn’t until 1956 that I was given one called Teldrin, if my memory is accurate, which was less sedating. Were these first-generation antihistamines?
Yes. Examples of 2nd generation antihistamines:
Cetirizine (Zyrtec)
Desloratadine (Clarinex)
Fexofenadine (Allegra)
Loratadine (Claritin)