Sandbox:Mounika
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Mounika Lakhmalla, MBBS[2]
Chronic Spontaneous Urticaria
Chronic spontaneous urticaria by definition is the presence of urticaria/hives, angioedema, or sometimes both for a duration of six weeks or longer. It affects adults more than children, and women are affected more often than men.
- Diagnosis of CSU is often clinical, based on the episodic appearance of characteristic urticarial lesions, with or without angioedema, on most days of the week, for a period of six weeks or longer. In 80 to 90 percent of adults and children with CSU, no specific etiology can be identified.
- Skin biopsy is not needed for routine diagnosis of CSU, although it is indicated to exclude urticarial vasculitis if there are signs or symptoms consistent with a vasculitic process or in the rare patients with features of mastocytosis.
- Tests used in investigation of pathogenesis include the autologous serum and plasma skin tests (ASST/APST), assays for autoantibodies directed against immunoglobulin (Ig)E or Fc-epsilon-RI, and also in vitro assessments of basophil function. However, these tests lack specificity and prognostic value, are not standardized across laboratories, and are not recommended for routine clinical use.
- Several hypotheses about the pathogenesis of chronic idiopathic urticaria have been proposed, although the data for each are incomplete, and none appear to be helpful for determining treatment or prognosis. The most accepted hypothesis involves histamine-releasing factors and defects in basophil signaling and/or function.
- CSU is a self-limited disease in the vast majority of patients.Spontaneous remission occurs in 30 to 50 percent of patients by one year, and the average duration of disease is two to five years. Up to 20 percent of patients still have symptoms persisting beyond five years. Those with more severe symptoms tend to have longer-lasting disease.
- Patients with chronic spontaneous urticaria are often frustrated and anxious
- Although no external cause is identified in most patients, numerous factors can aggravate the condition.
- Understanding these triggers and learning to avoid those that are relevant to the individual patient are critical components of successful management. Education should begin as soon as the diagnosis is made.
- H1 antihistamines are recommended as initial therapy for all patients with chronic spontaneous Urticaria.
- Less-sedating, second-generation agents (eg, cetirizine, levocetirizine, fexofenadine, loratadine, desloratadine)are more recommended over older first-generation agents (eg, hydroxyzine, diphenhydramine, chlorpheniramine, or mizolastine)
Treatment Response
- Around 50% of the patients may not achieve complete control of symptoms using standard doses of second-generation H1 antihistamines alone.
- a stepwise approach to increasing therapy is appropriate for this patient group(Non Responders).
- As we increase doses or as different agents are introduced, it is important to discontinue any that have not been beneficial, so that medications do not accumulate
One or more of the following interventions are recommended for those who have persistent symptoms:
- Increasing the dose of the second-generation H1 antihistamine to up to four times the standard dose (after which, international guidelines suggest adding Omalizumab)
- Adding a different second-generation antihistamine
- Adding an H2 antagonist
- Adding a leukotriene-receptor antagonist
- Adding a first-generation H1 antihistamine at bedtime
For patients whose symptoms persist, increasing the dose of first-generation H1 antihistamine gradually is suggested. These patients need to be informed about sedation and anticholinergic side effects.
Usage of Systemic glucocorticoids should be reserved for short-term control of refractory symptoms.
Symptoms that persist despite step 3 therapy or who are intolerant of dose advancement of first-generation H1 antihistamines are considered to have refractory disease.
Once symptoms are controlled, we continue the drug(s) required for control for a minimum of1 to 3 months before attempting to taper or discontinue medications.
We recommend extending this maintenance period even longer in patients whose symptoms were particularly difficult to suppress.