From the Guidelines
A skin biopsy can be helpful in distinguishing DRESS syndrome from drug-induced lupus, though it is not always definitive. When considering the diagnosis of DRESS syndrome versus drug-induced lupus, it's crucial to understand the histopathological features that may aid in differentiation. In DRESS syndrome, skin biopsies typically show interface dermatitis with vacuolar changes, spongiosis, and a dense lymphocytic infiltrate with eosinophils in the dermis, as seen in various studies 1. The presence of significant eosinophilic infiltration is particularly characteristic of DRESS.
Key Histopathological Features
- Interface dermatitis with vacuolar changes
- Spongiosis
- Dense lymphocytic infiltrate with eosinophils in the dermis
In contrast, drug-induced lupus skin biopsies often show interface dermatitis with vacuolar degeneration of the basal layer, but typically lack the prominent eosinophilic component seen in DRESS. Additionally, drug-induced lupus may show immunoglobulin and complement deposition at the dermal-epidermal junction on direct immunofluorescence, which is not typically seen in DRESS, as noted in studies like 1. However, there can be overlap in histological features, so the biopsy should be interpreted alongside clinical presentation, laboratory findings (such as eosinophilia in DRESS and positive ANA in drug-induced lupus), and the specific medication history.
Clinical Considerations
- Clinical presentation
- Laboratory findings (eosinophilia, ANA)
- Medication history (e.g., minocycline, hydralazine, procainamide for drug-induced lupus; aromatic anticonvulsants, allopurinol, sulfonamides for DRESS syndrome)
Given the potential for overlap and the importance of integrating all available information, the decision to perform a skin biopsy should be based on the individual patient's presentation and the need for diagnostic clarity, considering the most recent and highest quality evidence available, such as that from 1.
From the Research
Distinguishing DRESS Syndrome from Drug-Induced Lupus
- DRESS syndrome and drug-induced lupus are two distinct conditions that can present with similar symptoms, making diagnosis challenging.
- A skin biopsy may be helpful in distinguishing between the two conditions, as it can provide valuable information about the underlying pathology.
Histopathological Features of DRESS Syndrome
- Studies have shown that the histopathological features of DRESS syndrome are characterized by interface dermatitis, eczematous patterns, and the presence of eosinophils and neutrophils 2.
- The association of two or three patterns in a single biopsy is significantly more frequent in cases of DRESS than in nondrug-induced dermatoses.
Role of Skin Biopsy in Diagnosis
- A skin biopsy can be helpful in the diagnostic process of DRESS syndrome, as it can provide information about the presence of eosinophils, neutrophils, and other inflammatory cells 3.
- However, the diagnosis of DRESS syndrome is often made based on a combination of clinical and laboratory findings, including the presence of fever, facial edema, lymphadenopathy, and organ involvement.
Comparison with Drug-Induced Lupus
- Drug-induced lupus is a rare adverse reaction to certain drugs, characterized by symptoms resembling those of idiopathic systemic lupus erythematosus (SLE) 4, 5, 6.
- The diagnosis of drug-induced lupus is often based on the presence of antinuclear antibodies (ANA) and other autoantibodies, as well as a history of exposure to a specific drug.
- A skin biopsy may not be as helpful in distinguishing drug-induced lupus from DRESS syndrome, as the histopathological features of drug-induced lupus are not as well characterized.