Extraordinary Case Report“Macular Arteritis”: A Latent Form of Cutaneous Polyarteritis Nodosa?Al-Daraji, Wael MBBS, MSc, MRCP, MD*; Gregory, A Neal MPH, MD†; Carlson, J Andrew MD, FRCPC‡Author Information From the *Division of Pathology, School of Molecular Medical Sciences, Queen's Medical Centre, Nottingham, United Kingdom; †Upper Hudson Valley Dermatology, Castleton, NY; and ‡Department of Pathology, Albany Medical College, Albany, NY. Reprints: J. Andrew Carlson, MD, FRCPC, Division of Dermatopathology and Dermatology, Albany Medical College MC-81, 47 New Scotland Avenue, Albany, NY 12208 (e-mail: [email protected]). The American Journal of Dermatopathology: April 2008 - Volume 30 - Issue 2 - p 145-149 doi: 10.1097/DAD.0b013e31816407c6 Buy SDC Metrics Abstract Recently described macular arteritis presents as asymptomatic hyperpigmented macules, runs a chronic, indolent course, and shows lymphocytic arteritis at various stages of evolution ranging from fibrinoid necrosis to endarteritis obliterans. Herein, we present another case that was clinically suspected to be unilateral plantar pompholyx. A 47-year-old male presented with a 2-month history of persistent, reticulated, asymptomatic, nonblanching erythematous and brawny macules, and scattered, slightly scaly papules over the plantar instep of his left foot. Two punch biopsies extending to the subcutis revealed healed arteritis (endarteritis obliterans with fragmented elastic lamina) in the subcutis in one biopsy and purpura and hemosiderin deposition surrounding small subcutaneous arterioles and venules in the second. Additional histologic features included lymphocytic eccrine hidradenitis and chronic spongiotic dermatitis. Extensive laboratory work did not reveal evidence of systemic disease. Despite topical corticosteroid therapy, he has had persistent, asymptomatic disease after 6 months follow-up. The differential diagnoses considered included pigmented purpuric dermatitis, perniosis (chilblains), plantar eccrine hidradenitis, Buerger disease, livedo vasculopathy, and cutaneous polyarteritis nodosa. Cutaneous polyarteritis nodosa also runs a benign course and is denoted by muscular vessel vasculitis, which can resolve with retiform hyperpigmentation. Based on these overlapping clinical-pathologic features, macular arteritis might represent a latent, non-nodule forming chronic variant of cutaneous polyarteritis nodosa. © 2008 Lippincott Williams & Wilkins, Inc.