title: Detection of hypodense eosinophils by Percoll multilayer density gradient centrifugation in subjects with normal or slightly elevated eosinophilia. Poor reproducibility and eosinophils of density < 1.077 g/ml.
abstract: In patients with marked hypereosinophilia 'hypodense' and 'normodense' eosinophils have been found after density gradient centrifugation. Subsequently this terminology has also been used in studies of patients with milder eosinophilia. However, in these cases the differentiation between normo- and hypodense eosinophils was less clear. This might be due to the high imprecision of the test of density gradient centrifugation, as demonstrated in the first part of this study: the mean within-assay variance of the number of eosinophils in the different density layers was 35%. It was calculated that the test must be performed eight times to obtain an estimate of the true mean for the individual patient. In the second part of the study, the absolute number of 'hypodense eosinophils' in groups of patients with asthma (adults and children) and rheumatoid arthritis (adults) were compared to normal controls. Although a difference in the absolute number of hypodense eosinophils between groups of patients and controls could be demonstrated, the high imprecision of the test of density gradient centrifugation suggested that the technique used was not useful in an individual with normal or slightly elevated eosinophils in the peripheral blood.
authors.affiliation: Department of Immunology, Allergy and Rheumatology, University of Antwerp, Belgium.
authors.forename: M M
authors.initials: MM
authors.lastname: Moens
authors.forename: C H
authors.initials: CH
authors.lastname: Bridts
authors.forename: L S
authors.initials: LS
authors.lastname: De Clerck
authors.forename: H P
authors.initials: HP
authors.lastname: Van Bever
authors.forename: W J
authors.initials: WJ
authors.lastname: Stevens
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000473:pathology; D001249:Asthma / Q000473:pathology; D002469:Cell Separation; D002499:Centrifugation, Density Gradient; D002648:Child; D004802:Eosinophilia / Q000473:pathology*; D004804:Eosinophils / Q000166:cytology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011205:Povidone; D012822:Silicon Dioxide
chemical_list: C016039:Percoll; D012822:Silicon Dioxide; D011205:Povidone