Abnormal granulocytopoietic cell morphology Myelokathexis 2017-06-18T14:13:54Z The word myelo-kathexis is derived from the Greek words for marrow (myelo) retention (kathexis). Unlike other forms of severe neutropenia, myelokathexis is characterized by granulocytic hyperplasia in the bone marrow, which contains neutrophils with cytoplasmic vacuoles, nuclear hypersegmentation, and pyknotic nuclear lobes connected by thin filaments. Impaired egress of mature neutrophils from bone marrow causing neutropenia.