title: Hyposplenism: comparison of different methods for determining splenic function.
abstract: Asplenic patients are at risk for pneumococcal sepsis. Patients with hyposplenic function, such as associated with sickle cell disease (SCD), are also at risk. However, tests to assess splenic function are either unavailable or lacking standardization. The aim of this study was to compare different methods for determining splenic function. Eighteen patients with SCD (i.e., 10 heterozygous (SC) and 8 homozygous (SS) SCD patients), and eight splenectomized patients were compared to 10 controls. All subjects underwent spleen scintigraphy, after which functional splenic volumes (FSV) were calculated. FSV was compared to immunological function and B cell-subsets, as well as phagocytic function represented by the presence of Howell Jolly bodies (HJB) and percentages of pitted red cells (PIT). Heterozygous SCD (SC) patients had increased splenic volumes, but diminished FSV, homozygous SCD (SS) patients were asplenic. Splenectomized and SS patients had a strongly reduced phagocytic and immunological function. SC patients had reduced anti-polysaccharide responses without an increase in PIT. FSV correlated significantly with phagocytic and immunological function. HJB were indicative of splenic dysfunction, HJB absence was not indicative of normal functioning splenic tissue. Although visualizing HJB is methodologically advantageous to PIT, both are valid biomarkers of splenic dysfunction. The amount of non-switched memory B cells is strongly correlated to FSV.
authors.affiliation: Department of Infectious Diseases Tropical Medicine and AIDS, Academic Medical Center, Amsterdam, The Netherlands. a.j.lammers@amc.uva.nl
authors.forename: A J Jolanda
authors.initials: AJ
authors.lastname: Lammers
authors.forename: Alexander P N A
authors.initials: AP
authors.lastname: de Porto
authors.forename: Roelof J
authors.initials: RJ
authors.lastname: Bennink
authors.forename: Ester M M
authors.initials: EM
authors.lastname: van Leeuwen
authors.forename: Bart J
authors.initials: BJ
authors.lastname: Biemond
authors.forename: J Carel
authors.initials: JC
authors.lastname: Goslings
authors.forename: Jan
authors.initials: J
authors.lastname: van Marle
authors.forename: Ineke J M
authors.initials: IJ
authors.lastname: ten Berge
authors.forename: Peter
authors.initials: P
authors.lastname: Speelman
authors.forename: Joost B L
authors.initials: JB
authors.lastname: Hoekstra
mesh_terms: D000328:Adult; D000368:Aged; D000755:Anemia, Sickle Cell / Q000503:physiopathology; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology; D004908:Erythrocyte Inclusions / Q000648:ultrastructure; D004912:Erythrocytes; D004913:Erythrocytes, Abnormal / Q000648:ultrastructure; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D010587:Phagocytosis; D011877:Radionuclide Imaging; D012805:Sickle Cell Trait / Q000503:physiopathology; D013670:Sodium Pertechnetate Tc 99m; D013154:Spleen / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D013156:Splenectomy / Q000009:adverse effects; D013158:Splenic Diseases / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D014611:Vaccination; D055815:Young Adult
chemical_list: D000941:Antigens; D013670:Sodium Pertechnetate Tc 99m