BACKGROUND: Pigmented purpuric dermatosis (PPD) is a rare disease that is poorly understood but thought to result from inflammation of the capillaries causing extravasation of erythrocytes into the soft tissue. There are a variety of potential causes, including medications, such as acetaminophen and aspirin, abnormal humoral immunity, and excessive exercise. Although benign, PPD can be bothersome to patients due to associated pruritus, weeping, and poor cosmetic results. Treatment of this lesion is difficult, with no standardized regimen and a tendency for relapse once treatment is discontinued.

CASE REPORT: This case reports on a 77-year-old man who presented to an outpatient dermatology clinic with bilateral lower extremity edema with associated weeping and erythema for 1 year. A biopsy was conducted and resulted as PPD. He began treatment with excimer laser therapy after conservative and topical treatment options failed, with resolution of symptoms without recurrence for approximately 1 year.

CONCLUSIONS: PPD is notoriously difficult to treat, and historic treatment options include topical corticosteroids, oral supplements, and immunomodulators, all of which come with a range of adverse effects. However, new literature supports the use of phototherapy to treat PPD, with varying results. Previously implemented options include but are not limited to phototherapy with psoralen plus ultraviolet A, narrow band ultraviolet B, advanced fluorescence technology pulsed light, and fractional non-ablative 1540-nm erbium: glass laser, each with varying degrees of success. This case discusses the successful treatment of recalcitrant PPD with excimer laser therapy and maintenance of remission for approximately 1 year.

Keywords: Lasers, Excimer, Phototherapy, Pigmented purpuric eruption