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Acute leukemia should be considered if there are blasts on blood smear; in this case special blood tests (especially bone marrow aspiration and biopsy) are the next steps of diagnostic evaluation. Red blood cell fragments (schistocytes) are common in microangiopathic hemolytic anemias (such as TTP and DIC). Appearance of dacrocytes (“teardrop” erythrocytes) and nucleated erythrocytes should lead to further bone marrow investigation, since these findings are indicative of primary myelofibrosis and myelodysplastic syndrome. Elevated blood lactate dehydrogenase (LDH) and indirect bilirubin, combined with low haptoglobin level and a positive direct antiglobulin test (direct Coombs test), are common in patients with Evans syndrome, a disorder presenting with autoimmune hemolytic anemia and thrombocytopenia (both processes may occur at the same time, or, more commonly, different times) as a consequence of anti-platelet and anti-erythrocyte antibodies. Elevated LDH combined with renal function impairment may indicate TTP or hemolytic uremic syndrome (HUS). Blood coagulation tests disturbance: prolonged prothrombin time (PT), low fibrinogen and elevated D-dimers are typical for DIC. Elevated liver enzymes with or without elevated bilirubin, LDH and alkaline phosphatase should lead to the investigation of hepatic disease (viral hepatitis, drug-induced or toxic hepatitis), cirrhosis, and viral infection such as cytomegalovirus (usually only liver enzymes and LDH are elevated). Serological tests for viruses, blood cultures, anti-platelet antibodies, bone marrow biopsy and many other diagnostic tests can be performed at the discretion of the physician according to the presenting signs and course of the disease. One treatment approach is to direct treatment to the etiology of thrombocytopenia (e.g. discontinuation of the drug that caused thrombocytopenia, treatment of the underlying infection, immunoglobulin G (IgG) replacement, chemotherapy directed at CLL). Unfortunately, only in a minority of cases is the etiology of thrombocytopenia clear and the cause found. In addition, in some cases “curing” the underlying medical cause of the ITP may not change the platelet count. In a case of severe bleeding, if the etiology of thrombocytopenia is unknown, but not thought to be immunologic, platelet transfusion can be used to provide an immediate platelet increase. In contrast, if the underlying cause is immune, the effect from platelet transfusion may be minimal and at best very short-lived, and it should be reserved only for life-threatening bleeding (ideally transfused following intravenous immunoglobulin to “protect” the platelets). If the cause of thrombocytopenia is unknown and there are no contraindications, such as infections, corticosteroids may be used to increase the platelet count. More specific treatment plans usually depend on the underlying etiology of the thrombocytopenia.