Their diagnosis is usually based on the presence of medical signs and symptoms, and all of them seem to begin at the capillary level and result from an endothelial dysfunction occasioned by the administration of chemotherapy, calcineurin inhibitors, granulocyte-colony stimulating factor (G-CSF), infections, and allogeneic-derived reactivity (7–9). This evidence concerns the gene CSF3 and endothelial dysfunction.