Pseudo-storage pool disease due to platelet degranulation in EDTA-collected peripheral blood: a rare artifact

We report a patient who was referred for acute myocardial infarction and presented a pseudo-storage pool disease. The platelets from the blood collected with ethylene diamine tetra-acetic acid (EDTA) were moderately underestimated by the automated analyser, stained poorly on the blood smear and appeared agranular under the microscope. This artifactual anomaly does not occur in samples anticoagulated with citrate, heparin or the mixture citrate theophyline adenine dipyridamole. Reports of EDTA-induced pseudo-storage pool disease are scarce, possibly because underestimation of this poorly explained and difficult to diagnose phenomenon.