• Background and Design.—
The hemophagocytic syndrome (HPS) is characterized by fever, wasting, generalized lymphadenopathy, hepatosplenomegaly, and pancytopenia, often with associated coagulopathy. The most common cutaneous manifestations are panniculitis and purpura. Cytophagic histiocytic panniculitis fits within the spectrum of HPS, and the most consistent histopathologic feature in HPS is a proliferation of mature histiocytes that exhibit prominent erythrophagocytosis and cytophagocytosis. The clinical spectrum, the underlying causes, and the histopathologic features found in HPS are broad. The characteristic phagocytic histiocytes seen in HPS have been confused with malignant histiocytes in the past, but are now known to be reactive. The clinical findings, histologic, and immunohistochemical features of 10 cases of HPS with cutaneous lesions were reviewed. Immunohistochemical markers included KP-1, βF-1, UCHL-1, L-26, MAC-387, factor XIIIa, and S100 protein.
The HPS was associated with T-cell lymphoma and/or viral infection. Most biopsy specimens showed edema and hemorrhage with a lymphohistiocytic infiltrate and prominent histiocytic cells showing erythrophagocytosis and, in some cases, cytophagocytosis. The histiocytic cells showed positive reactions for KP-1 and negative reactions for the lymphoid markers. In all cases the lymphoid cells showed a mixed pattern with most cells positive for βF-1 and UCHL-1, and a small percentage positive for L-26.
In HPS, the prominent phagocytic histiocytes are reactive and are stimulated by T-cell lymphocytes, either neoplastic or in response to viral infection. Many of the findings in the HPS may also be due directly or indirectly to cytokines produced by proliferating T-cell lymphocytes and/or reactive phagocytic histiocytes.(Arch Dermatol. 1992;128:193-200)
Smith KJ, Skelton HG, Yeager J, Angritt P, Wagner K, James WD, Giblin WJ, Lupton GP. Cutaneous Histopathologic, Immunohistochemical, and Clinical Manifestations in Patients With Hemophagocytic Syndrome. Arch Dermatol. 1992;128(2):193-200. doi:10.1001/archderm.1992.01680120065005