Leucémie/lymphome T de l'adulte HTLV-1+

Adult T-cell leukemia/lymphoma (ATLL) is a lymphoproliferative disorder of mature T cells caused by human T-cell lymphotropic virus (HTLV-1). The clinical features of the disease can vary greatly. The most common acute subtype is characterised by a combination of generalized lymphadenopathy, hepatosplenomegaly, skin rash, hypercalcemia and circulating neoplastic cells. The diagnosis is suggested by the morphological, immunophenotypical and genetic characteristics of neoplastic cells, histopathological and immunohistochemical features of involved tissues and serological status of patients (HTLV-1 healthy carriers). To confirm the diagnosis it is necessary to show the clonal integration of HTLV-1 in neoplastic cells. Whatever the clinical subtype the prognosis is poor because of cell resistance to conventional intensive chemotherapy.     

Une nouvelle méthode de dosage direct du LDL cholestérol

LDL cholesterol (LDLC) is a major cardiovascular risk factor worldwide. National and International consensus panels have chosen this parameter for individual risk assessment and of monitoring lipid-lowering therapy in current medical practice. Recommendations for LDLC measurement are based on an indirect method, a calculation by Friedewald formula, which tends to underestimate LDLC as a function of increasing plasma triglycerides (TG).A new method for the direct measurement of LDLC was developed by SEBIA, combining an enzymatic measurement of cholesterol, with automated agarose gel electrophoresis. We have evaluated this method in comparison with ultracentrifugation and Friedewald formula on fresh serums from 725 subjects including 512 dyslipidemics [1]. The method is linear, sensitive and precise (total error = +2.88%, recommended < 4%, Freidewald = −6.72%). Serum storage at +4°C up to 3 days or at −80°C up to a week did not interfere with final results. Contrary to calculation, which tends to underestimate LDLC levels as a function of increasing plasma TG, the direct method was well correlated (r = 0.94) and stable for LDLC levels up to 5.07 g/L as compared with ultracentrifugation, whatever the level of TG even above 18 g/L.Thus at recommended decision cut-points, mean bias never exceeded +3%, contrary to calculated LDLC for which bias exceeded −20% at a TG level of 2.5 g/L. In hypertriglyceridemic subjects for whom cardiovascular risk is now established, the new method detects about 6 times more high-risk subjects with LDLC levels above the recommended cut-points. In these subjects Friedewald formula tended to underestimate LDLC, giving rise to risk assessment underestimation and inappropriate therapy.The new method allows a reliable assessment of LDLC, comparable in routine practice with what would be obtained by ultracentrifugation on the same serums. Precision, reproducibility and concordance are significantly improved compared with calculation by Friedewald formula, particularly in subjects with moderate to high plasma triglyceride. These results underscore the necessity for direct methods for the measurement of LDLC in routine practice, for risk assessment and monitoring of patients with a high risk of cardiovascular disease.