A 52-year-old white man was admitted to the hospital for anaphylaxis caused by multiple bee stings. His medical history was unremarkable. Physical examination showed he had a black lesion on his tongue, with hairlike projections that were palpable and covered much of the tongue. To the naked eye these appeared as discoloration (Figure). The lesion did not come off with scraping. The patient said he had had it for many years and denied any known cause. He was afebrile and his vital signs were stable. The rest of the physical examination was normal.

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