Drug eruptions — Clinical Case (Wikimedia Commons)

Diagnosis: Drug eruptions

Drug eruptions. A. Bullous dermatitis medicamentosa caused by sulfathiazole. B. Fixed drug eruption caused by phenolphtalein. C. Bullous erythema multiforme. D. Diffuse photosensitivity reaction.. Clinical photograph sourced from Wikimedia Commons (CC BY-SA 3.0). Attribution: Jmarchn.

Clinical Presentation

Morbilliform: symmetric erythematous macules/papules, often trunk first. Urticarial: wheals. Fixed drug eruption: well-demarcated violaceous plaques recurring at same site. SJS/TEN: targetoid lesions, mucosal erosions, epidermal detachment.

Clinical History

Detailed medication history with timeline is critical. New medications within 1-3 weeks for morbilliform, 4-8 weeks for DRESS. Previous drug reactions. Consider OTC medications, supplements, and recent contrast agents.

Treatment

Discontinue offending agent. Mild: topical corticosteroids, antihistamines. SJS/TEN: ICU care, wound management, consider IVIG or cyclosporine. DRESS: systemic corticosteroids with slow taper.

Differential Diagnosis

Viral exanthem, Morbilliform drug eruption, DRESS syndrome, SJS/TEN, Fixed drug eruption, AGEP

Key Learnings

DRESS has a longer latency (2-8 weeks) and involves internal organ dysfunction. SCORTEN predicts mortality in SJS/TEN. Always document drug allergies and consider cross-reactivity patterns.

Tags: drug eruption, adverse drug reaction, morbilliform, medication