Date Published: November 10, 2011
Publisher: BioMed Central
Author(s): Amin Kanani, Robert Schellenberg, Richard Warrington.
Urticaria (hives) is a common disorder that often presents with angioedema (swelling that occurs beneath the skin). It is generally classified as acute, chronic or physical. Second-generation, non-sedating H1-receptor antihistamines represent the mainstay of therapy for both acute and chronic urticaria. Angioedema can occur in the absence of urticaria, with angiotensin-converting enzyme (ACE) inhibitor-induced angioedema and idiopathic angioedema being the more common causes. Rarer causes are hereditary angioedema (HAE) or acquired angioedema (AAE). Although the angioedema associated with these disorders is often self-limited, laryngeal involvement can lead to fatal asphyxiation in some cases. The management of HAE and AAE involves both prophylactic strategies to prevent attacks of angioedema (i.e., trigger avoidance, attenuated androgens, tranexamic acid, and plasma-derived C1 inhibitor replacement therapy) as well as pharmacological interventions for the treatment of acute attacks (i.e., C1 inhibitor replacement therapy, ecallantide and icatibant). In this article, the authors review the causes, diagnosis and management of urticaria (with or without angioedema) as well as the work-up and management of isolated angioedema, which vary considerably from that of angioedema that occurs in the presence of urticaria.
Urticaria (hives) is a common disorder, occurring in 15-25% of individuals at some point in life [1,2]. It is characterized by recurrent, pruritic (itchy), pink-to-red edematous (swollen) lesions that often have pale centers (wheals) (see Figure 1). The lesions can range in size from a few millimeters to several centimeters in diameter, and are often transient, lasting for less than 48 hours [1-4]. Approximately 40% of patients with urticaria also experience angioedema (swelling that occurs beneath the skin) .
The diagnosis of urticaria, with or without angioedema, is based primarily on a thorough clinical history and physical examination. Based on the history and physical exam, diagnostic tests may also be considered to help confirm a diagnosis of acute, chronic or physical urticaria.
Strategies for the management of acute urticaria include avoidance measures, antihistamines and corticosteroids. For urticaria, antihistamines are the mainstay of therapy. Corticosteroids and various immunomodulatory/ immunosuppressive therapies may also be used for more severe cases, or for those patients who experience a poor response to antihistamines (see Figure 3).
The diagnosis of HAE and AAE is based upon a suggestive clinical history (i.e., episodic angioedema in the absence of urticaria affecting the skin, gastrointestinal and upper respiratory tracts) and the presence of abnormalities in specific complement proteins. Complement studies that should be ordered for patients with suspected HAE and AAE include: C4 (the natural substrate for C1) level, C1q level, C1 inhibitor antigenic level, and C1 inhibitor functional level . These studies should be performed when the patient is not receiving treatment, since the use of therapeutic interventions for AAE or HAE can alter laboratory results.
The treatment of idiopathic angioedema is similar to that of urticaria. The condition responds well to prophylactic antihistamines. In some individuals, corticosteroids are required. Alcohol and NSAIDs can exacerbate this condition and, therefore, avoidance is advised.
Urticaria is a common disorder that often presents with angioedema. It is generally classified as acute (lesions occurring for < 6 weeks), chronic (lesions occurring for > 6 weeks) and physical (lesions result from a physical stimulus). The disorder can usually be diagnosed on the basis of clinical presentation and history, however, diagnostic tests may be helpful for confirming the diagnosis. Second-generation, non-sedating H1-receptor antihistamines represent the mainstay of therapy for both acute and chronic urticaria; first-generation sedating antihistamines may be used as adjunctive therapy in patients with nocturnal symptoms. For severe, refractory chronic urticaria, short courses of oral corticosteroids and certain immunosuppressant and immunomodulatory therapies may be beneficial.
• Urticaria is a common disorder characterized by recurrent, pruritic (itchy) lesions with pale centers (wheals) that usually subside within 48 hours; it is often associated with angioedema.
Dr. Amin Kanani has received consulting fees and honoraria for continuing education from Scherring, GlaxoSmithKline, King Pharma, Merck Frosst, Novartis, CSL Behring and Talecris Biotherapeutics.