P6426Multinucleate cell angiohistiocytoma

Karina Ribeiro, MD, FTESM, S~ao Paulo, Brazil; Ana Paula Bucciaroni, MD, FTESM,S~ao Paulo, Brazil; Bruna Graziano, MD, FTESM, S~ao Paulo, Brazil; Gabriela Cezar,FTESM, S~ao Paulo, Brazil; Maria Cristina Camargo, FTESM, S~ao Paulo, Brazil;Ricardo Villa, FTESM, S~ao Paulo, Brazil; Sabrina Ribeiro, FTESM, S~ao Paulo, Brazil

Background: a patient with multinucleate cell angiohistiocytoma (MCAH).

Case report: a 74-year-old white woman presented with an asymptomatic purplepatch for 1 year. During the examination, a solitary, violaceous plaque of 1.5 cmwasobserved on the upper third of the left thigh. An excisional biopsywas performed, inview of the suspicion of Kaposi sarcoma (KS). The histopathologic examinationrevealed findings compatible with multinucleate cell angiohistiocytoma, withorthokeratotic epidermis, acanthosis, proliferation of well formed vascular channelson the reticular dermis, discretely desmoplastic, besides dendritic cells (fibrohis-tiocytic) with several nuclei on the dermis, discrete inflammatory infiltrated, madeof lymphocytes, mast cells, and occasional hemosiderophages.

Discussion: MCAH is a benign vascular proliferation of unknown etiology charac-terized by a solitary or multiple violaceous papules or plaques, between 1 and 15 cmin diameter. It generally affects the extremities of the body andmost rarely trunk andface. There is a higher incidence among women after their fourth decade. Thehistology reveals vascular hyperplasia, with proliferation of the cells of theconjunctive tissue, associated with the presence of multinucleated giant cells. It isclinically similar to KS.

Conclusion: MCAH is a benign, rare vascular disorder, an important differentialdiagnosis from KS, largely differing in prognosis and treatment.

APRIL 20

cial support: None identified.

Commer

P7117Necrotising infundibular crystalline folliculitis

Arif Aslam, MBChB, Salford Royal NHS Foundation Trust, Manchester, UnitedKingdom; Lynne Jamieson, MBChB, Salford Royal NHS Foundation Trust,Manchester, United Kingdom; Rebecca Brooke, MD, Salford Royal NHSFoundation Trust, Manchester, United Kingdom

A 73-year-old woman was referred to our dermatology department with a 12-monthhistory of an asymptomatic follicular papular eruption which had failed to respondto topical corticosteroids and oral antibiotics provided in primary care. Hersignificant medical history included a superficial spreading malignant melanomatreated 12 years ago. On examination there were well circumscribed widespreadwaxy erythematous crusted papules affecting the back and both lower legs (seephotos). Histologic examination was performed on an incisional biopsy on a lesionfrom the left lower leg (see photos). It showed partially squamous or fully squamouslined craters with appear to be centerd on follicular units. Within the crater there iskeratin, parakeratin, inflammatory, necrotic debris and amorphous material whichin some instances appears fibrillar. Calcification is also apparent. A PAS stain forfungal organismswas negative. The histologic appearances are those of a perforatingdisorder. The differential diagnosis includes perforating folliculitis, elastosis perfo-rans serpiginosa and a newly described entity necrotising infundibular crystallinefolliculitis (NICF). The histologic features in this case bear a striking resemblance tonecrotising infundibular crystalline folliculitis. Our patient responded to a 6-weekcourse of metronidazole with complete resolution of all the lesions (see photos).NICF is a folliculocentric disorder associated with filamentous crystalline deposits,enclosed by parakeratotic columns within partly necrotic follicular ostium andinfundibulum. It is an extremely rare condition with very few reported cases. It wasfirst reported in 2001 and it has been hypothesised that either physical or chemicalinjury or bacteria and Malassezia yeasts in the infundibulum of follicles may inducethe crystalline structures.

cial support: None identified.

Commer

13

P6020Scleroderma-like reaction to red tattoo ink

Jacqueline Fussell, MD, Geisinger Medical Center, Danville, PA, United States;Tammie Ferringer, MD, Geisinger Medical Center, Danville, PA, United States;Victor John Marks, MD, Geisinger Medical Center, Danville, PA, United States

Background: Hypersensitivity reactions to tattoos are variable. They can occurimmediately after tattooing up to decades later. The most commonly reported typesof reactions are lichenoid, granulomatous, sarcoidal, eczematous, and pseudolym-phomatous. Rarely have there been reports of scleroderma-like reactions.

Case report: A 38-year-old man presented with tenderness and pruritus isolated tothe red areas of a tattoo on his forearm. The black, red, and green skull had beentattooed at a professional tattoo parlor approximately 12 months before presenta-tion. Pruritus started about 2 months after tattooing. The red areas of the tattoo thenbecame warm, tender, and scaly. He was treated with oral clindamycin by hisprimary care physician due to concern for cellulitis, with no resolution ofsymptoms. He denied use of any topical medications to the area. At presentation,a punch biopsy of the affected area revealed features resembling lupus erythema-tosus, including interface dermatitis and follicular plugging but also deepersclerodermoid features were noted. He was treated with intralesional triamcinoloneacetonide 10 mg/mL and topical clobetasol 0.05% cream twice daily. At the 3-weekfollow-up, there was marked improvement of pruritus, tenderness, scaling, anderythema. Interestingly, he had no problemwith previous red tattoos not performedat a professional tattoo parlor. Also, patient had no history or symptoms ofscleroderma or other connective tissue disease and there were no lesions ofmorphea noted on examination.

Conclusion: This is an unusual case of lupus erythematosus and scleroderma-likereaction to red tattoo pigment. Dermal sclerosis and fibrosis have been noted inareas of tattoo months to years after tattooing but are throughout rather thanrestricted to a single pigment. Scleroderma-like hypersensitivity is a rarely reportedreaction to tattoo pigment and can occur in patients without signs of morphea orsystemic disease.

cial support: None identified.

Commer

P6331Seasonal variation in the incidence of lichen planuselike keratosis

Anne Neeley, MD, Saint Louis University, Saint Louis, MO, United States; NicoleBurkemper, MD, Saint Louis University, Saint Louis, MO, United States

Background: LPLK was first described in 1966 as solitary form of lichen planus. It isbelieved to represent chronic inflammatory involution of a solar lentigo orseborrheic keratosis. While many believe UV radiation plays a role in the pathogen-esis of LPLK, the true provocative stimulus is unknown.

Objective: The aim of this study was to demonstrate variation in the incidence ofLPLK from season to season. If LPLK are stimulated by exposure to UV radiation,there should be variation in their incidence in a climate with distinct seasons.

Methods: A search for all cases of LPLK signed out at our institution’s dermatopa-thology laboratory during the years 2007 to 2010 was performed usingourPowerPath database. Total number of specimens processed for hematoxylineeosinper monthwas used as a control. LPLK as ratio of total specimenswas plottedmonthby month using data from all 4 years.

Results: The search yielded 1680 cases diagnosed as LPLK. A statistically significantdifference (P \ .001) between the first 6 months and the last 6 months of thecalendar year was seen. There was no significant difference when the results werecompared season to season.

Limitations: The main limitation of this study is the variable lag time between onsetof a lesion and the date a biopsy was performed.

Conclusion: We found a significantly higher incidence of LPLK during the months ofJanuary-June when compared to July-December. The highest incidence was seen forthe months of February-June, suggesting a potential relationship with increased UVexposure during springtime months.

cial support: None identified.

Commer

J AM ACAD DERMATOL AB87