[Multiple osteonecroses and venous thrombosis: one case of patient with a novel mutation of protein C (N102S) and heterozygous for FV Leiden]. / Ostéonécroses et thromboses veineuses multiples : un cas de patient porteur d'une nouvelle mutation de la protéine C (N102S) et hétérozygote pour le facteur V Leiden.

The association of a thrombo-embolic venous disease and multiple osteonecroses occurring in the presence of biological risk factors for thrombosis is rarely described in the literature. We report here the case of a 35-year old patient with such clinical manifestations. This patient is heterozygous for a novel mutation of the protein C gene (N102S) and for FV Leiden polymorphism. The clinical history is characterized by numerous thrombo-embolic venous episodes associated with several episodes of epiphysis osteonecrosis requiring two hip total prostheses and two knee total prostheses. The particular clinical features here are the multiple osteonecroses and the unusual localisation of brain and genital thromboses. The absence of both venous thromboembolic and osteonecrosis events in the relatives presenting the same genetic pattern suggests broad phenotype variations in the clinical expression of these genetic abnormalities. In osteonecrosis associated with thrombophilia, some authors have proposed treatment with stanazolol, which increase circulating protein C concentration. The effectiveness of this drug among such patients should be evaluated by clinical studies.

[Role of the hemostasis laboratory in the etiologic approach to deep vein thrombosis]. / Place du laboratoire d'hémostase dans la démarche étiologique des thromboses veineuses profondes.

Thrombophilia is characterized by an inherited or acquired defect in the blood coagulation pathway leading to an increased risk for thrombosis. The etiological approach following confirmed venous thrombotic events should rule out medical or chirurgical risk factors. Thrombophilia should be sought by laboratory tests. The recent discovery of a blood coagulation defect: inherited resistance to activated protein C which is found to 20% of patients with former thrombotic events has changed current laboratory approach. Deficiencies of one of the anticoagulant proteins (antithrombin III, protein C, protein S) are found in 10% of the patients, similar to the frequency of antiphospholipid antibodies. These tests may be difficult to interpret immediately after the thrombotic event because of various factors such as inflammatory states or anticoagulant treatments. Therefore this abnormal tests should be confirmed on a later sample analysis far from the event. The discovery of an inherited blood coagulation pathway defect may affect the duration of treatment, prophylaxis in situations with circumstantial risk factors and requires familial analysis. Inherited resistance to activated protein C may be associated with another inherited defect leading to an increased risk for thrombosis.

Cyclical shock with hyperglobulinemia.

Two personal cases are compared with CLARKSON's case, enabling one to describe a syndrome arising in adults without a family history, and characterised by episodes of repeated shock (cyclical shock) with hemoconcentration and hypoproteinemia. The physiopathological mechanism is an acute hyperpermeability. Two cases out of three took a fatal course, with a negative autopsy. In the three cases, the presence of light kappa chain IgG type monoclonal dysglobulinemia was proven. The diagnosis of multiple myeloma can be excluded. Comparison of this syndrome with periodic disease and primary amyloidosis can be envisaged.