title: Retrospective study of reticulocyte indices as indicators of iron-restricted erythropoiesis in dogs with immune-mediated hemolytic anemia.
abstract: Iron-restricted erythropoiesis can occur as a result of an absolute deficiency of iron stores, inflammation-mediated iron sequestration, or functional iron deficiency (in which release of stored iron is slower than the iron uptake by erythroid precursors during intense erythropoiesis). Reticulocyte indices are used to identify iron-restricted erythropoiesis, with the reticulocyte hemoglobin content (CHr) being the most commonly used index in human patients. Dogs with immune-mediated hemolytic anemia (IMHA) may have iron-restricted erythropoiesis caused by inflammation-mediated iron sequestration and/or functional iron deficiency, which could contribute to anemia severity and blunt the regenerative response in some dogs. To investigate this possibility, reticulocyte indices were examined retrospectively in 14 dogs (2-15 years of age; 9 spayed females, 1 intact female, 4 neutered males) with IMHA, and no clinical evidence of blood loss was found to suggest absolute iron deficiency. Five dogs (34%) had CHr below the preestablished lower reference limit (24.5 pg), and hematocrit was significantly lower in these dogs (p = 0.042, nonpaired t-test). Our results suggest that some dogs with IMHA may have iron-restricted erythropoiesis as a result of functional iron deficiency, inflammation-mediated iron sequestration, or (less likely) absolute iron deficiency. Further study is warranted to evaluate if dogs with IMHA may benefit from parenteral iron therapy.
authors.affiliation: Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN (Schaefer)Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY (Stokol) dschaefe@utk.edu.
authors.forename: Deanna M W
authors.initials: DM
authors.lastname: Schaefer
authors.affiliation: Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN (Schaefer)Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY (Stokol).
authors.forename: Tracy
authors.initials: T
authors.lastname: Stokol
mesh_terms: D000743:Anemia, Hemolytic / Q000175:diagnosis / Q000662:veterinary*; D000818:Animals; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis*; D004285:Dogs; D004920:Erythropoiesis; D005260:Female; D007501:Iron / Q000097:blood; D008297:Male; D011237:Predictive Value of Tests; D012156:Reticulocytes / Q000166:cytology*; D012189:Retrospective Studies
chemical_list: D007501:Iron
keywords: Canine; functional iron deficiency; iron sequestration; reticulocyte hemoglobin content