[Corticosteroid resistance thrombocytopenia in connective tissue disorders and vasculitis].

In rheumatic diseases there can appear deteriorations of the thrombocytes number in the sense of increase or decrease of this number.Thrombocytosis has 3 major causes: (1) reactive or secondary thrombocytosis; (2) family thrombocytosis and (3) clonal thrombocytosis. Thrombocytopenia, that is, decrease of the thrombocytes number below 150000/mmc is unusually in rheumatic diseases. Their mechanism of production can be central and peripheral. In the connective tissue disorders and vasculitis thrombocytopenia can has different causes: (1) decrease thrombocytes production; (2) splenic platelets sequestration; (3) peripheral platelets consumption; (4) peripheral immune mediated destruction of platelets. Thrombocytopenia is present in the following rheumatic diseases: systemic lupus erythematosus, antiphospholipid syndrome, rheumatoid arthritis, Felty syndrome, vasculitis. Steroids are the conventional first line therapy for immune thrombocytopenia. Corticosteroid resistance can develop as a result of deteriorations that appear to the any level of pathway action of corticosteroids.