DRESS syndrome

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What this article covers

• Overview

  Definition: drug reaction with eosinophilia and systemic symptoms (DRESS), also called drug-induced hypersensitivity syndrome, is a severe delayed T-cell-mediated drug reaction with skin and internal-organ involvement.

• Epidemiology

  Uncommon but serious: among the severe cutaneous adverse reactions, with mortality up to about 10 percent, usually from liver failure.

• Risk factors

  Specific culprit drugs: aromatic anticonvulsants (phenytoin, carbamazepine, lamotrigine), allopurinol, sulfonamides, vancomycin, and minocycline.

• Pathophysiology

  Delayed T-cell hypersensitivity: drug-specific T cells drive a systemic inflammatory response with prominent eosinophilia.

• Clinical features

  Facial edema: the hallmark, with a morbilliform eruption starting on the face and upper trunk and spreading.

• Differential diagnosis

  Stevens-Johnson syndrome / toxic epidermal necrolysis: mucosal erosions and skin sloughing with a positive Nikolsky sign, earlier onset.

• Diagnosis

  Establish with the RegiSCAR criteria: DRESS is scored using the RegiSCAR system, which combines fever, an extensive rash (often over 50 percent body surface area) with features suggesting DRESS…

• Management

  First-line, stop the culprit drug immediately and avoid the whole cross-reacting class permanently.

• Complications

  Fulminant hepatitis and liver failure: the leading cause of death.

• Prognosis

  Serious but usually recoverable: most patients recover with drug withdrawal and steroids, though mortality reaches about 10 percent, chiefly from hepatic failure.

• Prevention

  Never re-expose to the culprit drug or its class after DRESS, and document a class contraindication.