Neutrophilic phlebitis is characteristic of intestinal Behçet's disease and simple ulcer syndrome.

AIM: To characterize the histological features of intestinal Behcet's disease and simple ulcer syndrome and to clarify the possible mechanisms involved in their development by analysing the type of inflammatory infiltrates in the diseased intestine and the expression of adhesion molecules on endothelial cells. METHODS AND RESULTS: Tissue samples from 10 patients diagnosed as having intestinal Behcet's disease or simple ulcer syndrome were studied. Immunohistochemical studies were performed on paraffin-embedded tissue using a labelled streptavidin-biotin method. In all cases, phlebitis was remarkably seen in submucosal inflammatory lesions, but the adjacent arteries were not affected. Inflammatory infiltrates around the affected vessels consisted of neutrophils and mononuclear cells, and neutrophils predominated over CD68+ macrophages and lymphocytes. The majority of mononuclear cells were CD3+ T cells, and CD4+ cells were more frequent than CD8+ T cells. As for adhesion molecule expression, intercellular adhesion molecule-1, but not vascular cell adhesion molecule-1, was expressed in most endothelial cells of the vessels with phlebitis, some of which were also positive for HLA-DR. CONCLUSION: Neutrophilic phlebitis may be involved in the pathogenesis of intestinal Behcet's disease and simple ulcer syndrome.

Malignant histiocytosis-like B-cell lymphoma, a distinct pathologic variant of intravascular lymphomatosis: a report of five cases and review of the literature.

Malignant histiocytosis (MH)-like B-cell lymphoma (BCL) is a neoplastic proliferation of large B cells clinically characterized by fever, hepatosplenomegaly, haemophagocytosis and abnormal laboratory data, without lymphadenopathy or skin lesions. Interestingly, most cases have been reported in Asian patients, and it is unclear whether MH-like BCL is biologically distinct from conventional large B-cell lymphomas. We report five Japanese patients with MH-like BCL. Biopsied specimens of bone marrow, liver and/or spleen showed infiltration of neoplastic B cells accompanied by haemophagocytosing histiocytes. Lymphoma cells were positive for CD19, CD20 and HLA-DR surface antigens, and negative for CD5 and CD10. In four cases elevated serum levels of interleukin (IL)-6 and the soluble IL-2 receptor isoform were noted, but not IL-1beta, IL-2 or tumour necrosis factor-alpha. Autopsies of two cases were pathologically diagnosed as intravascular lymphomatosis (IVL). Based on these observations, the current and nine previous cases reported as MH-like BCL in Japan were re-evaluated. They appear to form a peculiar variant of IVL, characterized by bone marrow involvement at presentation, haemophagocytic syndrome, and a rapidly aggressive clinical course, but rarely neurological complications or skin lesions. This variant may merit separate consideration because of the problems posed in the initial diagnosis and therapeutic approaches.