Di guglielmo first called attention to a condition characterized primarily by neoplastic hyperplasia of erythroblastic tissue. Later on, both acute and chronic forms of this disorder were recognized. In addition, it was noted that usually there was neoplastic myeloid involvement as well. It is generally accepted now to refer to cases of leukemia in which neoplastic erythroid hyperplasia is striking but which usually also demonstrate some neoplastic myeloid involvement as Di Guglielmo's syndrome and to group these with the myeloproliferative disorders. It may and frequently does arise de novo as other acute leukemias or may be found as a sequel to other myeloproliferative diseases.
Recently, several reports have appeared describing various chromosomal abnormalities noted in some patients with Di Guglielmo's syndrome.1-5 As with other acute leukemias, the abnormalities are multiple and vary from patient to patient. However, all these reports cite hypodiploidy as a constant feature. We recently studied