PMC10081908_01
Generalized bullous fixed-drug eruption. (a, b) A positive rechallenge phenomena and reappearing of generalized bullous formation after restarting of metformin. (c, d) Bullous formation with central dusky appearance after restarting of metformin on the lower extremities and perineum.
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They flared up and widespread skin denudation and bullous lesions occurred with erosions and ulcers compatible with a positive rechallenge test to the metformin (Figures 1(c) and 1(d)).
Histopathology of fixed-drug eruption associated with metformin. The histopathologic feature shows vacuolar interface dermatitis, necrotic keratinocytes, and eosinophil infiltration.
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Histopathology demonstrated vacuolar interface dermatitis, apoptotic keratinocytes, and pigment incontinence associated with eosinophil infiltration that were consistent with bullous FDE (Figure 2).
Postinflammatory hyperpigmentation in generalized fixed-drug eruption. A positive dechallenge phenomenon and subsiding of the bullous formation after the discontinuation of the metformin.
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After discontinuation of metformin, the progression of the disease was stopped (Figure 3) and the patient was treated with oral prednisolone (40 mg daily) and cyclosporine-A (100 mg daily).