Dermatology MCQ - Inflammatory Dermatoses - Urticaria Management

A 32-year-old woman with a 9-month history of chronic spontaneous urticaria returns for follow-up. She has been taking loratadine 10 mg daily for the past 3 weeks with minimal improvement. She continues to experience widespread, pruritic wheals daily, which are significantly impacting her sleep and quality of life. According to current international guidelines, the most appropriate next step in management is:

A. Add a first-generation sedating H1-antihistamine (e.g., hydroxyzine) at bedtime.
B. Switch loratadine to a different second-generation H1-antihistamine.
C. Increase the dose of loratadine to 20 mg daily (or up to four times the standard dose).
D. Initiate a course of oral prednisone 40 mg daily for one week.
E. Order autologous serum skin testing and a comprehensive autoimmune panel.

Correct Answer: C. Increase the dose of loratadine to 20 mg daily (or up to four times the standard dose).

Answer & Explanation

Explanation:

This question tests knowledge of the evidence-based, stepwise approach to chronic spontaneous urticaria (CSU) management, as outlined by guidelines from organizations like the EAACI/GA²LEN/EDF/WAO.

Step 1 is a standard dose of a second-generation H1-antihistamine (e.g., loratadine 10 mg, cetirizine 10 mg, fexofenadine 180 mg). If, after 1-2 weeks, control is not adequate, the guidelines unequivocally recommend Step 2: increasing the dose of the second-generation H1-antihistamine up to fourfold.

• Why this is correct: This approach is supported by clinical trials demonstrating that higher doses are more effective and maintain a favorable safety profile, as second-generation antihistamines are highly specific for H1-receptors with minimal sedative or anticholinergic effects at these increased doses.

The other options are incorrect or not guideline-supported as the next step:

• A. Add a first-generation sedating H1-antihistamine: While sometimes used in practice for refractory itch at night, this is not the recommended second step. The significant side effects (sedation, cognitive impairment, anticholinergic effects) make them less desirable than simply increasing the dose of a safer, second-generation drug.

• B. Switch to a different second-generation H1-antihistamine: There is little evidence to support that switching between drugs in the same class is beneficial. If one second-generation antihistamine is ineffective, the guideline-recommended action is to increase its dose, not to switch to another.

• D. Initiate a course of oral prednisone: While systemic corticosteroids can be highly effective for short-term control of severe flares, they are not recommended for long-term management due to their well-known adverse effects. They should be reserved for acute exacerbations and used at the lowest dose and shortest duration possible. They do not have a role in the routine step-up protocol.

• E. Order autologous serum skin testing and a comprehensive autoimmune panel: Extensive laboratory workup is not indicated in routine CSU without suggestive history. These tests do not guide initial management steps and are considered in refractory cases in a specialized setting.

Key Associations for Urticaria Management

• Stepwise Management Protocol:

  1. Step 1: Standard dose of a second-generation H1-antihistamine.

  2. Step 2: Increase the dose of the second-generation H1-antihistamine (up to 4x standard dose).

  3. Step 3: Add omalizumab (anti-IgE), which is highly effective for refractory CSU.

  4. Step 4: Consider cyclosporine or other immunosuppressants (e.g., montelukast, dapsone) for cases failing omalizumab.

• Adjunctive Therapies: Patient education on trigger avoidance (if identified), cooling emollients, and avoiding NSAIDs (which can exacerbate urticaria in up to 30% of patients) are important.

• Prognosis: CSU has a variable course. Many patients experience remission within 1-5 years, but a subset has a more prolonged and treatment-resistant disease.

• Histopathology: Not used for diagnosis or management of routine CSU. A biopsy is only performed if urticarial vasculitis is suspected, showing leukocytoclasia (neutrophilic debris), fibrinoid deposits in vessel walls, and extravasated red blood cells.