From Wikipedia - Reading time: 6 min
| Generalized bullous fixed drug eruption | |
|---|---|
| Other names | Bullous drug eruption,[1] multilocular bullous fixed drug eruption[2]: 554 |
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| Drug eruption: Bullous dermatitis medicamentosa caused by sulfathiazole. | |
| Specialty | Dermatology |
Generalized bullous fixed drug eruption (GBFDE) most commonly refers to a drug reaction in the erythema multiforme group.[3]: 129 These are uncommon reactions to medications, with an incidence of 0.4 to 1.2 per million person-years for toxic epidermal necrolysis and 1.2 to 6.0 per million person-years for Stevens–Johnson syndrome.[3]: 129 The primary skin lesions are large erythemas (faintly discernible even after confluence), most often irregularly distributed and of a characteristic purplish-livid color, at times with flaccid blisters.[2]: 554
A rare and severe variation of fixed drug eruption, generalized bullous fixed drug eruption involves blisters and erosions involving at least 10% of the body's surface area, affecting three of the six anatomic sites: the head and neck, the anterior and posterior trunk, the upper and lower extremities, and the genitalia.[4]
Fixed drug eruptions are linked to anti-infective (ß-lactam antibiotics, tinidazole, and acyclovir), analgesics (acetaminophen (paracetamol), mefenamic acid, and metamizole), non-steroidal anti-inflammatory drugs (NSAIDs), anti-epileptic (carbamazepine), psychoactive (barbiturates, codeine, and others), and other miscellaneous medications (omeprazole, contrast media, loratadine, and allopurinol).[4]
In cases where the clinical presentation is unclear, a skin biopsy may be necessary to confirm the diagnosis of GBFDE. A subepidermal blister or denuded epidermis, vacuolar alterations at the dermo-epidermal junction, and a variable number of necrotic keratinocytes within the lesional intact epidermis are characteristic histopathologic findings of GBFDE.[5]
Antihistamines and topical steroids are used in symptomatic therapy. Antibiotics should be given if an infection is thought to be present.[6] It is also important to counsel the patient to stay away from the offending medication.[7]