Article

Biomarkers of splenic function in infants with sickle cell anemia: baseline data from the BABY HUG Trial

Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390-9063, USA.
Blood (Impact Factor: 10.43). 03/2011; 117(9):2614-7. DOI: 10.1182/blood-2010-04-278747
Source: PubMed

ABSTRACT We evaluated spleen function in 193 children with sickle cell anemia 8 to 18 months of age by (99m)Tc sulfur-colloid liver-spleen scan and correlated results with clinical and laboratory parameters, including 2 splenic biomarkers: pitted cell counts (PIT) and quantitative Howell-Jolly bodies (HJB) enumerated by flow cytometry. Loss of splenic function began before 12 months of age in 86% of infants in association with lower total or fetal hemoglobin and higher white blood cell or reticulocyte counts, reinforcing the need for early diagnosis and diligent preventive care. PIT and HJB correlated well with each other and liver-spleen scan results. Previously described biomarker threshold values did define patients with abnormal splenic function, but our data suggest that normal spleen function is better predicted by PIT of ≤1.2% or HJB ≤55/10(6) red blood cells and absent function by PIT ≥4.5% or HJB ≥665/10(6). HJB is methodologically advantageous compared with PIT, but both are valid biomarkers of splenic function. This trial was registered at www.clinicaltrials.gov as #NCT00006400.

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    • "Howell-Jolly bodies are small nuclear remnants from erythroblasts that cannot be removed from red blood cells if the spleen is absent. In sickle cell disease, there is a strong correlation [3] between the number of red blood cells harbouring Howell-Jolly bodies, or the number of “pitted cells” (i e, red blood cells containing small vesicles) in circulation and the intensity of functional hyposplenism. In Plasmodium infections, the spleen contributes to innate resistance and limits the magnitude of parasitaemia. "
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    Malaria Journal 08/2013; 12(1):271. DOI:10.1186/1475-2875-12-271 · 3.49 Impact Factor
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    • "The evaluation of splenic function still rests chiefly on indirect markers, such as the pitted erythrocyte count, Howell Jolly body count, and Tc99m uptake. These tools have produced robust data regarding spleen function in vast longitudinal cohort studies of SCD infants (Rogers et al, 2011). However, the correlation between the results and the vulnerability to infection remains indirect. "
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    British Journal of Haematology 03/2012; 156(5):643-8. DOI:10.1111/j.1365-2141.2011.08999.x · 4.96 Impact Factor
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    • "This is potentially a rapid way of assessing splenic function , and correlates closely with pitted red cell counts and functional spleen scans . Few laboratories currently offer this assay ( Rogers et al , 2011 ) . "
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