Confetti leucoderma can occur in a variety of unrelated skin disorders and is often a diagnostic challenge. We describe a 33year-old man with a history of mycosis fungoides and vitiligo. He developed disseminated 1-2 ...Confetti leucoderma can occur in a variety of unrelated skin disorders and is often a diagnostic challenge. We describe a 33year-old man with a history of mycosis fungoides and vitiligo. He developed disseminated 1-2 mm round- shaped leucodermic lesions 6 months after psoralen photochemotherapy and 12 months after systemic therapy with interferon. The skin lesions had a discrete hyperkeratotic scale. Multiple skin biopsies and immunohistochemical studies showed lamellar orthohyperkeratosis, papillomatosis, hypomelanotic keratinocytes but a normal number of melanocytes. Langerhans cells, in contrast, were reduced in lesional skin. Electron microscopy disclosed only a few type I and II melanosomes in lesional melanocytes, while keratinocytes were largely devoid of any melanosomes. This constellation of clinical, immunohistochemical and ultrastructural findings has not been reported before and distinguishes our case from leucoderma punctatum, idiopathic guttate hypomelanosis and disseminated hypopigmented keratoses. We suggest that the skin lesions observed in our patient represent an unusual response to ultraviolet damage to melanocytes followed by reactive epidermal hyperkeratosis.展开更多
Indeterminate cell histiocytosis is a rare disorder, in which the predominant cells have the characteristics of both Langerhans cells and macrophages. We, in this study, describe 18 patients and compare them with thos...Indeterminate cell histiocytosis is a rare disorder, in which the predominant cells have the characteristics of both Langerhans cells and macrophages. We, in this study, describe 18 patients and compare them with those previously publishe d. Most patients were adults with either solitary or multiple red-brown papules or nodules. While most lesions were con-fined to the skin, both conjunctival a nd bony involvement was seen. Histologically, the lesions showed patterns resemb ling those described for xanthogranulomas, with predominantly oncocytic (nine pa tients), spindled (five patients), scalloped (two patients) or vacuolated (two p atients) macrophages. The accompanying infiltrate was mainly lymphocytic, althou gh eosinophils and occasionally plasma cells were seen. All lesions were positiv e for macrophage markers, such as KP1 (GD68)-and Ki-M1p, as well as for S-100 protein and showed variable reactivity for CD1a. No Birbeck granules were seen ultrastructurally in one patient. Some patients shared features with sinus histi ocytosiswith massive lymphadenopathy. It is unclear whether this disorder is a s eparate entity or represents various macrophage disorders identified at various time points in the inflammatory response.展开更多
文摘Confetti leucoderma can occur in a variety of unrelated skin disorders and is often a diagnostic challenge. We describe a 33year-old man with a history of mycosis fungoides and vitiligo. He developed disseminated 1-2 mm round- shaped leucodermic lesions 6 months after psoralen photochemotherapy and 12 months after systemic therapy with interferon. The skin lesions had a discrete hyperkeratotic scale. Multiple skin biopsies and immunohistochemical studies showed lamellar orthohyperkeratosis, papillomatosis, hypomelanotic keratinocytes but a normal number of melanocytes. Langerhans cells, in contrast, were reduced in lesional skin. Electron microscopy disclosed only a few type I and II melanosomes in lesional melanocytes, while keratinocytes were largely devoid of any melanosomes. This constellation of clinical, immunohistochemical and ultrastructural findings has not been reported before and distinguishes our case from leucoderma punctatum, idiopathic guttate hypomelanosis and disseminated hypopigmented keratoses. We suggest that the skin lesions observed in our patient represent an unusual response to ultraviolet damage to melanocytes followed by reactive epidermal hyperkeratosis.
文摘Indeterminate cell histiocytosis is a rare disorder, in which the predominant cells have the characteristics of both Langerhans cells and macrophages. We, in this study, describe 18 patients and compare them with those previously publishe d. Most patients were adults with either solitary or multiple red-brown papules or nodules. While most lesions were con-fined to the skin, both conjunctival a nd bony involvement was seen. Histologically, the lesions showed patterns resemb ling those described for xanthogranulomas, with predominantly oncocytic (nine pa tients), spindled (five patients), scalloped (two patients) or vacuolated (two p atients) macrophages. The accompanying infiltrate was mainly lymphocytic, althou gh eosinophils and occasionally plasma cells were seen. All lesions were positiv e for macrophage markers, such as KP1 (GD68)-and Ki-M1p, as well as for S-100 protein and showed variable reactivity for CD1a. No Birbeck granules were seen ultrastructurally in one patient. Some patients shared features with sinus histi ocytosiswith massive lymphadenopathy. It is unclear whether this disorder is a s eparate entity or represents various macrophage disorders identified at various time points in the inflammatory response.
