Clinical Report: Omalizumab-Induced Bullous Erythema Multiforme

Overview

This case study presents a 36-year-old female patient who developed bullous erythema multiforme (BEM) following omalizumab treatment for chronic spontaneous urticaria. Initial treatment included methylprednisolone and IVIG, which was ineffective. The condition improved with increased methylprednisolone dosage and the addition of oral upadacitinib.

Background

Bullous erythema multiforme is an acute immune-mediated mucocutaneous disease that can be triggered by various medications, including biologics like omalizumab. Understanding the potential for such adverse reactions is crucial for clinicians.

Data Highlights

No numerical data or trial data available in the source material.

Key Findings

• A 36-year-old female developed BEM after receiving omalizumab for chronic spontaneous urticaria.
• Symptoms included generalized wheals, fever, chills, and fatigue 17 days post-injection.
• Laboratory tests showed elevated eosinophil count and IgE levels.
• Skin biopsy revealed focal epidermal necrosis and massive eosinophilic infiltration.
• Initial treatment with methylprednisolone and IVIG was ineffective.
• Condition improved with increased methylprednisolone dosage and addition of oral upadacitinib.

Clinical Implications

Clinicians should be vigilant for rare adverse reactions such as BEM in patients receiving omalizumab.

Conclusion

This case highlights the potential for omalizumab to induce BEM.

Related Resources & Content

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5. Erythema Multiforme - StatPearls - NCBI Bookshelf
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8. Erythema Multiforme - StatPearls - NCBI Bookshelf
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10. Adverse Cutaneous Reactions to Monoclonal Antibodies: Stevens-Johnson Syndrome, Toxic Epidermal Necrolysis, Erythema Multiforme, and Fixed Drug Eruption – A Systematic Review