What are these “bruises” on a man’s arm?

The occurrence of new bruises on his arms disturbs a 69-year-old man. He reports no history of trauma or use of aspirin or other anticoagulants. The patient denies hemoptysis, hematuria, hematochezia, epistaxis, and other bleeding.

Your workup includes which of the following?

A. Platelet count.

B. Urinalysis.

C. Prothrombin time.

D. Partial thromboplastin time.

E. All of the above.

F. None of the above.

(Answer on next page

Answer: Bateman, or actinic, purpura

Coagulation studies were not warranted here, F; the lack of widespread bruising and bleeding did not suggest a systemic problem.

Bateman, or actinic, purpura occurs in persons with a history of extensive sun exposure. As seen in this patient, the patches are confined to sun-exposed surfaces and arise on a background of sun-damaged skin. Treatment consists of daily applications of sunscreen to prevent further damage and to allow the skin to repair itself.