Anti-MDA-5 Dermatomyositis Presenting with Rapidly Progressive Interstitial Lung Disease: A Cautionary Tale.

A 68-year-old Indian man presented with a pruritic eruption on his neck, back, elbows, knees, and the dorsum of his hands. He was initially treated for possible Lyme's disease by his primary care physician, but without improvement. Then he developed daily chills and fevers up to 101 °F, as well as shortness of breath. A chest radiograph showed patchy airspace opacities suggestive of atypical pneumonia, and the patient was treated with levofloxacin and prednisone. Although prednisone diminished the eruption, the patient continued to experience fever, malaise, and generalized weakness, at which point he was hospitalized. Blood cultures and an antinuclear antibodies (ANA) were negative and extensive lab workup was only notable for an elevated erythrocyte sedimentation rate (ESR) (63 mm/hr, Reference Range 0-22), mild transaminitis (AST 77 U/L, Reference Range 10-40), hyponatremia (131 mEq/L, Reference Range 135-145) and elevated ferritin (440, Reference Range 20-500). The patient was discharged on 20 mg of prednisone, with referral to rheumatology and dermatology for possible autoimmune diseases.

Primary Cutaneous CD8+ T-cell Lymphoma, an Indolent and Locally Aggressive Form Mimicking Paronychia.

CD8 T-cell lymphomas comprise a wide spectrum of lymphomas, many which have yet to be formally classified. We present a case of a 43-year-old woman with an enlarging tumor distal to the distal interphalangeal joint of the fourth finger, compressing the underlying nail matrix. Magnetic resonance imaging showed bony involvement of the underlying distal phalanx. Histology showed a dense epidermotropic and pandermal infiltrate composed of medium-sized, uniformly pleomorphic lymphocytes with cleaved nuclei, which raised the possibility of primary cutaneous CD8 aggressive epidermotropic cytotoxic T-cell lymphoma. However, the patient's clinical photograph was inconsistent with this diagnosis. Other diagnoses, such as primary cutaneous acral CD8 T-cell lymphoma-a provisional entity, were also considered but did not capture all the features of this patient's lymphoma. We propose to classify this case as a primary cutaneous CD8 T-cell lymphoma, an indolent and locally aggressive form.

Intraepidermal proliferation of Merkel cells within a seborrheic keratosis: Merkel cell carcinoma in situ or Merkel cell hyperplasia?

Intradepidermal proliferation of Merkel cells without any dermal component has been interpreted as either a hyperplastic process secondary to chronic ultraviolet radiation or a neoplastic process, namely Merkel cell carcinoma (MCC) in situ. The recent criteria that have been proffered to diagnose MCC in situ, unfortunately, are identical to those that have been applied to Merkel cell hyperplasia in the past, posing a diagnostic quandary when faced with an intraepidermal proliferation of Merkel cells. Most previously reported cases of MCC in situ have occurred within associated epithelial lesion that includes solar (actinic) keratosis and squamous-cell carcinoma in situ. Similarly, Merkel cell hyperplasia has been reported to occur in association with a variety of epithelial lesions as well as on chronically sun-damaged skin. Herein, a case of an intraepidermal proliferation of Merkel cells within a seborrheic keratosis is presented accompanied by a discussion on whether the proliferation represents another case of Merkel cell carcinoma in situ or an incidental hyperplastic process on chronically sun-damaged skin.