Marie-Christine Kyrtsonis1, Dimitrios Maltezas2. 1. Hematology Section, First Department of Propaedeutic Internal Medicine, National and Kapodistrian University of Athens Medical School, Laikon Hospital, Athens, Greece. Electronic address: mck@ath.forthnet.gr. 2. Hematology Section, First Department of Propaedeutic Internal Medicine, National and Kapodistrian University of Athens Medical School, Laikon Hospital, Athens, Greece.