Diagnostic Criteria in Sézary's Syndrome: A Multiparameter Study of Peripheral Blood Lymphocytes in 32 Patients with Erythroderma

In order to define additional diagnostic criteria for the early diagnosis of Sézary's syndrome (SS), peripheral blood lymphocytes of 32 patients with erythroderma, including 8 patients with SS, 4 patients with erythrodermic mycosis fungoides, 14 patients with an erythroderma on the basis of atopic or chronic dermatitis, and 6 patients with erythrodermic psoriasis, were investigated by computer-assisted morphometry. The degree of nuclear indentation, expressed as the nuclear contour index (NCI), was measured on electron micro-graphs. The mean NCI and the percentages of cerebriform mononuclear cells (CMC), defined by a NCI ≥ 6.5, were calculated. In addition, the percentages of lymphocytes, T and B cells, and the distribution of T-cell sub-populations as defined by Fe-receptors (Tμ, Tγ) and monoclonal antibodies (OKT3, OKT4, OKT8, HLA-DR) were determined.Statistical analysis showed as most discriminating parameters for the differentiation between SS and benign forms of erythroderma: high percentages of lymphocytes (50% or more), an expanded OKT3+, OKT4+ population with an OKT4/OKT8 ratio > 10, a mean NCI value ≥ 5.5, the presence of more than 20% CMC, as well as the presence of cells with a NCI ≥ 11.5. The total leukocyte and lymphocyte counts, as well as the percentages of B, T, Tμ, and Tγ cells had limited value for the early diagnosis of SS