Drug reaction with eosinophilia and systemic symptoms

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a severe, idiosyncratic reaction to certain medications. It is characterized by a combination of skin eruptions, hematologic abnormalities, lymphadenopathy, and internal organ involvement. The condition is potentially life-threatening and requires prompt recognition and management.

Clinical Features

DRESS syndrome typically presents 2 to 8 weeks after exposure to the offending drug. The hallmark features include:

• Fever: Often high-grade and persistent.
• Rash: A widespread, morbilliform or exfoliative dermatitis is common. Facial edema is also frequently observed.
• Hematologic abnormalities: Eosinophilia is a key feature, but leukocytosis and atypical lymphocytes may also be present.
• Lymphadenopathy: Generalized lymph node enlargement is often noted.
• Internal organ involvement: Hepatitis is the most common, but renal, pulmonary, cardiac, and neurological systems can also be affected.

Pathophysiology

The exact mechanism of DRESS is not fully understood, but it is believed to involve a complex interplay of genetic, immunological, and metabolic factors. Genetic predispositions, such as certain HLA alleles, have been associated with increased risk. Reactivation of human herpesvirus 6 (HHV-6) and other herpesviruses has also been implicated in the pathogenesis.

Common Offending Drugs

Several drugs have been associated with DRESS syndrome, including:

• Anticonvulsants: Such as phenytoin, carbamazepine, and lamotrigine.
• Antibiotics: Such as sulfonamides and minocycline.
• Allopurinol: Commonly used for gout.
• Antiretrovirals: Such as abacavir.

Diagnosis

The diagnosis of DRESS is primarily clinical, supported by laboratory findings. The RegiSCAR scoring system is often used to aid in diagnosis, which considers clinical features, laboratory findings, and the exclusion of other conditions.

Management

The cornerstone of management is the immediate withdrawal of the offending drug. Supportive care and systemic corticosteroids are commonly used to control inflammation and organ involvement. In severe cases, other immunosuppressive therapies may be required.

Prognosis

The prognosis of DRESS can vary. While many patients recover completely with appropriate management, some may experience long-term sequelae or even fatal outcomes, particularly if there is significant organ involvement.

Also see

• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Eosinophilia
• Hypersensitivity reactions