title: Assessment of dysplastic hematopoiesis: lessons from healthy bone marrow donors.
abstract: BACKGROUND
  According to WHO 2008 guidelines, the required percentage of cells manifesting dysplasia in the bone marrow to qualify as significant is 10% or over in one or more hematopoietic cell lineages, but this threshold is controversial. No 'normal' values have been established. Therefore, we investigated dyshematopoiesis in bone marrow aspirate squash preparations of 120 healthy bone marrow donors.
  
  
  METHODS
  Bone marrow squash slides of 120 healthy unrelated bone marrow donors were examined independently by 4 experienced morphologists. Samples were taken from the first aspiration during the harvest. Bone marrow preparation and assessment were performed according to WHO recommendations and ICSH guidelines.
  
  
  RESULTS
  More than 10% dysmyelopoiesis could be detected in 46% of bone marrow aspirate squash preparations with 26% in 2 or more cell lineages and 7% in 3 cell lineages in healthy bone marrow donors. Donors under the age of 30 years exhibited more dysgranulopoietic changes and dysmegakaryopoietic changes (P<0.001) compared to the older donors. Female donors showed more dysgranulopoietic changes than male donors (P = 0.025). The concordance rate between the 4 investigators was modest in dysgranulopoiesis but poor in dyserythropoiesis and dysmegakaryopoiesis.
  
  
  CONCLUSIONS
  The poor reliability of the 10% cut off was partly related to the proximity of the current criteria to the observed cut-off mean values of the normal population. These findings question the current WHO threshold of the 10% or over necessary for the percentage of cells manifesting dysplasia to be considered significant, and suggest that either a higher threshold would be more appropriate or different thresholds should be set for each lineage.
authors.affiliation: Medizinische Klinik und Poliklinik I, Universitätsklinikum Dresden, Fetscherstraße 74, 01307 Dresden, Germany. stefani.parmentier@uniklinikum-dresden.de
authors.forename: Stefani
authors.initials: S
authors.lastname: Parmentier
authors.forename: Johannes
authors.initials: J
authors.lastname: Schetelig
authors.forename: Kerstin
authors.initials: K
authors.lastname: Lorenz
authors.forename: Michael
authors.initials: M
authors.lastname: Kramer
authors.forename: Robin
authors.initials: R
authors.lastname: Ireland
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schuler
authors.forename: Rainer
authors.initials: R
authors.lastname: Ordemann
authors.forename: Gabi
authors.initials: G
authors.lastname: Rall
authors.forename: Markus
authors.initials: M
authors.lastname: Schaich
authors.forename: Martin
authors.initials: M
authors.lastname: Bornhäuser
authors.forename: Gerhard
authors.initials: G
authors.lastname: Ehninger
authors.forename: Frank
authors.initials: F
authors.lastname: Kroschinsky
mesh_terms: D000293:Adolescent; D000328:Adult; D001853:Bone Marrow / Q000473:pathology*; D019070:Cell Lineage; D015331:Cohort Studies; D004920:Erythropoiesis / Q000502:physiology*; D005260:Female; D006098:Granulocytes / Q000473:pathology*; D006410:Hematopoiesis / Q000502:physiology*; D006801:Humans; D008297:Male; D008533:Megakaryocytes / Q000473:pathology*; D008875:Middle Aged; D015588:Observer Variation; D011379:Prognosis; D014019:Tissue Donors; D055815:Young Adult