Thrombocytopenia and pseudothrombocytopenia: a clinical and laboratory problem.

During a 4-month period, the patients with thrombocytopenia (N = 14) at a haematological outpatient clinic were subjected to a special laboratory investigation. Evidence of pseudothrombocytopenia was found in 5 of the patients. 1 patient with a giant platelet syndrome associated with deficient platelet function was also found. It is concluded that pseudothrombocytopenia and various thrombocytopathies provide a significant confounding factor in the management of patients with alleged thrombocytopenia. It is therefore suggested that the initial diagnostic work-up of alleged thrombocytopenia patients should include an assessment of platelet morphology in addition to an overall haemostatic test (bleeding time) and platelet function tests.