Perforating Plaque-Type Pretibial Sarcoidosis With Granulomatous Phlebitis

To the Editor: An 80-year-old woman presented with a 3-year history of asymptomatic lesions of the lower extremities. Physical examination showed well-circumscribed infiltrated erythematous to yellow plaques with slightly elevated borders involving pretibial skin (Fig. 1A). Histological examination revealed multiple noncaseating epithelioid granulomas with multinucleated giant cells in the dermis (Fig. 1B), accompanied by a mild lymphocytic infiltrate. There were nests of histiocytes in the epidermis, with focal epidermal thinning and an overlying mound of parakeratosis, suggesting transepidermal elimination/perforation (Fig. 1C). Muscular vein at the dermal–subcutaneous junction was surrounded by multinucleated giant cells with associated partial destruction of the muscular layer (Fig. 2A). Elastica van Gieson staining confirmed that the involved vessel was a vein and highlighted disruption, fragmentation, and loss of the elastic lamina in the areas infiltrated by sarcoidal granulomas (Figs. 2B, C). Dermal mucin deposition was not detected. Liver and kidney functions were normal, and blood glucose levels were within normal ranges. Angiotensin-converting enzyme and soluble IL-2 receptor serum levels were normal, and neither PR3-antineutrophil cytoplasmic antibody nor MPO-antineutrophil cytoplasmic antibody was detected. Computed tomography showed small nodular shadows and mediastinal lymphadenopathy. Ophthalmological examination revealed uveitis. Ulcers developed within the plaques, which were improved by application of topical alprostadil alfadex ointment.FIGURE 1.: A, Well-circumscribed erythematous plaques with mild scales and slightly elevated erythema at the periphery of the lower leg. B, Histological features showing noncaseating epithelioid cell granulomas with lymphocyte infiltration in the dermis (×40). C, Sarcoid granuloma within the epidermis, along with parakeratosis in the overlying stratum corneum (×400). Transepidermal elimination of sarcoidal granulomas is indicated by arrows.FIGURE 2.: A, Granulomatous phlebitis at the dermal–subcutaneous junction is characterized by an angiocentric infiltrate of histiocytes and multinucleated giant cells in and around the affected vessel wall with partial destruction of the muscular layer (×200). B, Elastica van Gieson staining revealed that the involved vessel is a vein (×200). Dense infiltration of sarcoidal granulomas with cuffing around and in the affected vessel walls. C, Disruption, fragmentation, and loss of the elastic lamina are observed at higher magnification (×400).We diagnosed this patient's cutaneous lesions on the lower extremities as plaque-type sarcoidosis. Necrobiosis lipoidica (NL) should be included in the differential diagnosis because NL is a granulomatous dermatosis commonly affecting pretibial sites, and NL-like lesions can be seen in systemic sarcoidosis.1 However, in our case, necrobiotic degeneration of collagen surrounded by inflammatory granulomatous reaction was not observed. Also, this patient did not have diabetes. Leukocytoclastic or granulomatous vasculitis is sometimes observed in cutaneous sarcoidosis.2–8 In a previous report, granulomatous vasculitis was observed in over 30% of patients (12/42), among whom venous involvement was observed in 11 patients.3 In a review by Yazdani Abyaneh et al,4 granulomatous vasculitis in sarcoidosis is characterized by its association with chronic sarcoidosis and clinical presentation with ulcers and livedo; while subcutaneous veins and arteries can be involved,4 and dermal venules are affected more often.3 Histopathology of sarcoidal vasculitis in dermal or subcutaneous vessels was characterized by dense infiltration of sarcoidal granulomas cuffing around and in the affected vessel walls, and disruption and loss of the elastic lamina. Previous studies have suggested that granulomatous vasculitis, necrotizing granulomas, and hyaline degeneration were possible causes of ulceration in sarcoidosis; however, the mechanism of ulceration remains uncertain. A recent review collected 34 cases, in which 85% (29/34) involved the legs, and other locations such as the face, arms, trunk, and genital area were also affected.9 Another survey of 22 Japanese patients with ulcerative sarcoidosis also revealed that leg ulcers were most common (n = 16). Two patients had ulcers in multiple locations (unknown:1).10 Our patient developed small ulcers within the plaque, which responded to topical therapy. Transepidermal elimination is sometimes seen in sarcoidosis, as we reported previously.11,12 Recently, Ismail et al13 reviewed reports on transepithelial elimination in sarcoidosis and demonstrated that histological features of transepidermal elimination of sarcoidal granuloma are not rare. Transepidermal elimination features were observed in cutaneous sarcoidosis involving the face, lower extremities, vulva, and scalp. In a case reported by Hagari et al,14 transepidermal elimination was observed in the sarcoidosis plaques on the lower leg, similar to our case. In conclusion, this is a unique case of cutaneous sarcoidosis affecting both the muscular vein and epidermis.