**2. Conclusion**

IgE-mediated immunologic pathways [9]. In addition, some drugs such as vancomycin, narcotic analgesics, barbiturates, neuromuscular blockers, and radiocontrast agents may cause urticarial eruption via direct mast cell degranulation [9, 10]. Nonsteroidal anti-inflammatory drugs may also trigger urticaria by interfering with arachidonic acid metabolism via cyclooxygenase 1 enzyme inhibition. This blockage leads to increased synthesis of cysteinyl leukot-

Physically induced urticarias are thought to occur as a result of increased mast cell sensitivity to environmental stimuli. Physical factors that may trigger urticaria include ultraviolet light, pressure, vibration, exercise, water contact, cold or heat exposures, and increased body

Systemic diseases can also be the underlying cause of urticaria. Therefore, the presence of any accompanying systemic symptoms is significant. Autoimmune and rheumatologic diseases constitute the majority of this group [12]. Systemic diseases include cutaneous vasculitis, systemic lupus erythematosus, celiac disease, diabetes mellitus, Sjögren's syndrome, rheumatoid arthritis, autoimmune thyroid disease, and mastocytosis [1, 12]. Malignancies may also trig-

Elementary lesion of urticarial eruption is papule or plaque with erythema and edema. Circumscribed, pink-to-red lesions elevated from the skin vary in size and shape. These plaques which may tend to merge with central pallor can affect any region of the body [14]. Pruritus is the main annoying symptom which mostly interferes with daily activities of the patients [15]. Although a single urticarial lesion is transient, repetitive character of the eruption is a significant problem. Lesions persisting beyond 24 h with residual petechia or hyperpigmentation, especially if accompanied by systemic symptoms such as fever and arthralgia, may suggest urticarial vasculitis in differential diagnosis and warrant skin biopsy [16].

Angioedema may accompany urticaria if the mast cells in the deeper dermis and subcutaneous tissue were involved in reactions. When this occurs, the lips and eyelids are the regions mainly affected [1]. Urticaria may also be a component of severe systemic allergic reactions, anaphylaxis, and so patients should always be examined for accompanying signs and symptoms such as flushing, swollen lips and tongue, difficulty in breathing, hoarse voice, hypotension, dizziness, hypotonia, syncope, nausea, vomiting, abdominal pain, and incontinence [17].

Diagnosis of urticaria is mostly based on anamnesis and physical examination. Due to the transient nature of the rash, there may be no lesions during a doctor visit. In this case, the clinical history of intensely pruritic lesions that heal within a few hours may be the only clue for urticaria diagnosis. In uncertain cases, asking patients to take a photo when they have a rash is a helpful method. It may be advisable to mark a single lesion and note the time it appeared and disappeared to determine the duration. Observation of characteristic erythematous and edematous papules and plaques supports the diagnosis. Association with angioedema and/or

Skin biopsy is not indicated for the diagnosis of urticaria unless there is suspicion of urticarial vasculitis or mastocytosis. If vasculitis is suspected, an additional skin sample should be taken

rienes. This form of urticarial reaction is called pseudoallergy [10].

4 A Comprehensive Review of Urticaria and Angioedema

ger urticaria and the disease tends to be persistent in this case [13].

anaphylaxis should always be kept in mind and questioned [1, 2].

temperature [11].

Generally, the disease is self-limited and it shows regression in a few weeks for most cases. Some patients may have persistent symptoms for months or years and the disease is considered chronic beyond 6 weeks.

If possible, the prevention of trigger is the first step of treatment. Treatment aim is to control symptoms with minimal side effects. H<sup>1</sup> antihistamines are the drugs most commonly used for this purpose. Second-generation H<sup>1</sup> antihistamines, such as cetirizine and loratadine, are used as first-line treatment options. These newer, non-sedative antihistamines are more preferred than first-generation ones such as hydroxyzine and diphenhydramine. First-generation antihistamines may have also the disadvantage of anticholinergic side effects in addition to their sedative effects. In unresponsive cases, dose increment up to fourfold of standard therapeutic doses is recommended by the latest guidelines [1, 21]. Increasing the dose of a particular antihistamine is thought to be superior to the combined use of multiple antihistamines at standard doses [21]. H<sup>2</sup> antihistamines may be used in combination with H<sup>1</sup> antihistamines.

Short-term systemic glucocorticoid therapy may be administered in addition to antihistamines for acute urticarial attacks, particularly when accompanied by angioedema [1]. Longterm usage of systemic glucocorticoids is not recommended because of potential side effects.

Antileukotrienes, such as montelukast and zafirlukast, are generally added to antihistamines as second-line treatment options in chronic cases refractory to high-dose antihistamines. Immunosuppressive agents, especially cyclosporine, are efficient to treat chronic urticaria but potential side effects must always be kept in mind. Dapsone, hydroxychloroquine, sulfasalazine, and mycophenolate are other less recommended drugs for the treatment of urticarial [1, 21]. Omalizumab, which is a safer alternative to those mentioned above, has recently come to the forefront in the treatment of chronic urticaria. It is an anti-IgE monoclonal antibody which has a good efficacy and safety profile [22, 23]. It also has the ease of use with monthly subcutaneous injections.

Since chronic urticaria treatment may become complicated, treatment switch, or combination is not surprising for most cases.
