Diagnosis and Management of DRESS Syndrome
The management of DRESS syndrome requires immediate discontinuation of the causative medication, hospitalization, and systemic corticosteroid therapy as the mainstay of treatment. 1
Diagnostic Approach
Step 1: Identify Key Diagnostic Features
- Skin rash (typically morbilliform, confluent, maculopapular eruption)
- Eosinophilia (>500 cells/μL)
- Systemic symptoms (fever >38°C)
- Internal organ involvement (liver, kidney, lung, heart)
- Temporal relationship to drug exposure (2-6 weeks after initiation) 2
- Lymphadenopathy
Step 2: Laboratory Evaluation
- Complete blood count with differential (look for eosinophilia, atypical lymphocytes)
- Liver function tests (elevated transaminases)
- Renal function tests (BUN, creatinine)
- Consider viral studies (HHV-6, HHV-7, EBV, CMV) 1
Step 3: Skin Biopsy (if diagnosis is uncertain)
- Look for interface dermatitis, perivascular lymphocytic infiltration with eosinophils
Step 4: Apply Diagnostic Criteria
- Use validated diagnostic criteria (RegiSCAR or Japanese consensus group) to confirm diagnosis 3
Management Protocol
Step 1: Immediate Actions
- Immediately discontinue the suspected culprit medication 1
- Hospitalize the patient; severe cases should be admitted to ICU or burn unit 1
- Consider photographic documentation of skin lesions for monitoring progression
Step 2: Systemic Corticosteroid Therapy
- For moderate cases: IV methylprednisolone 0.5-1 mg/kg/day 1
- For severe cases with significant organ involvement: IV methylprednisolone 1-2 mg/kg/day 1
- Convert to oral steroids once response is noted
- Taper steroids slowly over at least 4 weeks to prevent rebound 4, 1
Step 3: Supportive Care
- Topical emollients and high-potency topical corticosteroids for skin symptoms 4
- Oral antihistamines for pruritus
- Fluid and electrolyte management
- Nutritional support
- Infection prevention measures 1
Step 4: Management of Steroid-Resistant Cases
- Consider IVIG (1-2 g/kg) for steroid-unresponsive cases 5
- Alternative immunosuppressants like cyclosporine may be considered in refractory cases 1, 6
Step 5: Specialist Consultation
- Consult appropriate specialists based on organ involvement:
- Hepatology for liver involvement
- Nephrology for kidney involvement
- Pulmonology for lung involvement
- Cardiology for cardiac involvement 1
Step 6: Monitoring and Follow-up
- Daily monitoring of:
- Vital signs
- Skin involvement
- Complete blood count
- Liver and kidney function tests
- Other affected organ systems 1
- Continue treatment until:
- Resolution of skin manifestations
- Normalization of laboratory abnormalities
- Resolution of organ dysfunction 1
Important Considerations
Avoiding Common Pitfalls
- Delayed recognition: Early diagnosis is critical, especially after the 6th week of treatment with high-risk medications 1
- Premature steroid tapering: Can lead to rebound symptoms and worsening of condition 1
- Reintroduction of culprit medication: Must be permanently avoided, including structurally related compounds 1
- Inadequate monitoring: DRESS can have a prolonged course with flares during steroid tapering
Testing for Drug Causality
- Patch testing and delayed intradermal testing may help identify culprit drugs 4
- For DRESS, the sensitivity of patch testing is >50% for many drugs
- Testing should be delayed until ≥6 months after complete healing of reaction and/or ≥1 month after discontinuation of systemic corticosteroids 4
- Given the imperfect negative predictive value, patients with a negative test should still avoid the suspected culprit drug 4
Long-term Follow-up
- Monitor for potential sequelae including autoimmune diseases
- Provide patient education about avoiding culprit medication and cross-reactive drugs
- Create a comprehensive medical alert regarding drug allergy
By following this structured approach to diagnosis and management, dermatologists can effectively treat DRESS syndrome and minimize its potentially life-threatening complications.