The patient is a 72-year-old teacher who presents with pruritus affecting his upper back and scalp for the past seven days after cleaning a chicken coop.

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The patient is a 72-year-old teacher who presents with pruritus affecting his upper back and scalp for the past seven days after cleaning a chicken coop.

The pruritus causes him to scratch, resulting in excoriation. The itch disturbs his sleep and makes focusing on daily tasks difficult. He reports that he has previously had similar symptoms which have been self-limiting, resolving after a few weeks, but has not previously sought medical attention.

He is not aware of any close contacts with similar symptoms.

On examination, there is excoriation and erythematous papules and erosions on the back and scalp, with crusting and hypopigmented patches surrounding the sites of excoriations. The digital webs and groin are spared. There are no signs of bleeding or dermatitis.