Is this worsening rash related to occupational exposures?

Case 3:

During the past year, a 48-year-old man has had joint pain as well as this worsening rash on his hands. He is a construction worker, and he attributes the symptoms to his occupational exposure. He does not want to complain for fear of losing his job.

Answer on next page

The lesions of contact dermatitis are less well-defined than those of psoriasis. Lichen planus is less scaly than psoriasis. Palmar keratoderma is generally not erythematous. RA is in the differential of psoriatic arthritis; the presence of psoriatic skin and nail lesions in this patient suggested the latter diagnosis. Laboratory tests can differentiate RA from psoriatic arthritis.The presence of scaly erythematous plaques, subungual hyperkeratosis, and onycholysis pointed to the diagnosis of psoriasis, A, with psoriatic arthritis and dactylitis. Because treatment with methotrexate or cyclosporine was not an option for this patient, he elected to use an injectable biologic agent, and his condition significantly improved. It is important to be aggressive to minimize the development of destructive joint changes and to coordinate care with a rheumatologist if you are not comfortable with the various treatment options. The sudden onset of psoriasis with dactylitis would also suggest the need to test for HIV infection because there is an association between the two conditions.