[DIC and peripheral gangrene in a severe Plasmodium falciparum malaria: the coagulation-inflammation cycle with Plasmodium falciparum as a model]. / CIVD et gangrène périphérique dans un cas de paludisme sévère : le cycle coagulation-inflammation appliqué au Plasmodium falciparum.

Peripheral gangrene with disseminated intravascular coagulation (DIC) during severe Plasmodium falciparum malaria has already been described but is unfrequent. We report here the case of a 62-year-old man admitted in the intensive care unit of our hospital for severe Plasmodium falciparum malaria with disseminated intravascular coagulation (DIC) and peripheral gangrene of his toes that needed amputation. Pathophysiological mechanisms leading to DIC in malaria can be used as a model to explain the relation between coagulation and inflammation. Therapeutic targeting of coagulation, by acting on inflammation, could be useful to limit the coagulation-inflammation cycle.

[Peripheral blood Sézary cells and the diagnosis of Sézary syndrome]. / Recherche de cellules de Sézary dans le sang périphérique: morphologie ou immunophénotype?

Sézary syndrome (SS) is a rare and aggressive cutaneous lymphoma, and its diagnosis is based both on clinical, histological and biological features. None of these criteria taken alone is specific, and the two clinical observations reported here agree with this. Peripheral blood involvement, due to the presence of a variable number of Sézary cells, has been recently fully delineated by the ISCL/EORTC international organizations, and taken into account in the diagnosis and the prognosis of this syndrome. Identification and quantification of peripheral blood Sézary cells on the blood smear is an essential criterion for the diagnosis and is sufficient when associated with relevant clinical or/and histological grounds. Flow cytometry is another tool to demonstrate Sézary cells within the peripheral blood mononuclear cells. The authors discuss about the respective advantages and limits of morphology and flow cytometry in the identification and enumeration of circulating Sézary cells. Molecular biology is helpful in peculiar situations.

[Bone marrow necrosis in two patients with neoplastic disorders]. / Nécrose médullaire chez deux patients atteints de maladies cancéreuses.

Bone marrow necrosis is defined by extensive necrosis of the myeloid tissue and bone marrow stroma. Diagnosis is done on characteristic cytological pattern of the bone marrow aspiration and/or biopsy. We report two observations. The first patient, aged 75, has been hospitalized for fever, asthenia and lower back pain. An haematological malignancy was suspected after observation of a few peripheral blood blast cells, but necrosis was found on the bone marrow aspiration and could not lead to further haematological diagnosis. Within next days, the white blood cell count and the number of blasts increased, leading to the diagnosis of acute monoblastic leukaemia. A chemotherapy was started but the patient died 20 days after admission. The second patient, aged 28, has been hospitalized for severe bleeding a few days after the diagnosis of a metastatic gastric tumour. The bone marrow aspiration, made for the evaluation of a thrombocytopenia, showed a massive necrosis. The patient deceased shortly after hospitalization. According to literature, bone marrow necrosis is in most instances secondary to either an haematological malignancy (60%) or to a solid tumour (30%), but only at times observed with a non-malignant disorder. Bone pain, fever, cytopenias and elevated serum lactic dehydrogenase and alkaline phosphatase are frequently reported, but are mostly non specific of the diagnosis in these malignant conditions. Examination of the bone marrow leads to the diagnosis: cells are pycnotic, scarcely recognizable in a background of amorphous extracellular eosinophilic proteinaceous material, and histology shows disappearance of fat spaces with preservation of the bone tissue. Tissue hypoxemia due to microcirculation failure may be the main mechanism leading to the necrosis, whatever the related disorder. Supportive care together with specific therapy of the causal disease must be started promptly. The prognosis depends on the underlying illness and is generally very poor when extensive necrosis is observed.

New insight in antiplatelet therapy monitoring in cardiovascular patients: from aspirin to thienopyridine.

Antiplatelet therapy is used to reduce the risk of ischemic events in patients with cardiovascular disease. The balance of benefits and risks of antiplatelet drugs in cardiovascular disease has been evaluated in large-scale randomised trials, however the absolute benefit for an individual patient and a specific platelet-active drug needs further evaluation. Several well-conducted studies have demonstrated a substantial inter-individual variability in platelet responsiveness to drugs. The historical "gold standard" test of platelet function (optical aggregation) has been extensively used for measuring the effect of antiplatelet drugs, but has limitations. New tests developed (i.e. PFA-100®, VerifyNow®) may overcome some of these limitations but they do not correlate well with each other. Despite these unresolved methodological questions, several recent clinical studies, but not all, suggest a significant correlation between antiplatelet resistance status and serious vascular events. In these conditions, laboratory monitoring for antiplatelet therapies raises several questions: (i) the necessity of a consensus regarding the definition of resistance and the relevant test, (ii) the demonstration that biological resistance has clinical significance, and (iii) the clinical impact of individually adjusting the antiplatelet therapy. Therefore, it is not currently appropriate to test patients or to change therapy on the basis of such tests, other than in prospective and adequately powered clinical trials.