case_images: PMC11779660_01
case_images: Clinical images of lichenoid eruption at presentation. A, Violaceous flat-topped papules and bullae on the right lateral aspect of the lower portion of the abdomen. B, Multiple lacy reticular erosions on the buccal mucosa and (C) hard palate consistent with erosive oral lichenoid eruption.
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case_images: Examination was notable for violaceous flat-topped papules, many with overlying bullae, over her lower extremities, abdomen, and back (Fig 1, A). Oral erosions were also noted on the hard palate and buccal mucosa with overlying lacy reticular Wickham striae (Fig 1, B, C).
case_images: Lichenoid interface dermatitis with papillary to focally reticular dermal perivascular lymphocytic infiltrate and admixed scattered eosinophils, consistent with a lichenoid drug reaction. (Hematoxylin-eosin stain; original magnification: x200)
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case_images: Pathology obtained from affected skin on the abdomen revealed a lichenoid interface dermatitis with a perivascular lymphoeosinophilic infiltrate and negative direct immunofluorescence (Fig 2).
case_images: Violaceous papules coalescing into large plaques, with peripheral collarettes of scale and bullae over the left lateral aspect of the lower extremity, 1 month into hydroxychloroquine and tacrolimus treatment.
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case_images: One week later the patient received another infusion of pembrolizumab leading to rash progression with more extensive violaceous plaques over the flank and extremities (Fig 3).
case_images: Clinical images of oral lichenoid eruption after treatment. A, Complete clearance of erosions on the buccal mucosa and (B) hard palate, 6 months into hydroxychloroquine treatment.
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case_images: Two months after hydroxychloroquine initiation, the patient was tapered off prednisone entirely, discontinued topical steroids, and her ICI was resumed; at this time, she was entirely clear of both oral and skin disease (Fig 4, A, B).