GI14 - Blood Reticulocyte Hemoglobin Concentration as a Marker of Iron-deficient Erythropoiesis in Canine Chronic Inflammatory Enteropathy

Abstract:

Background: Non-regenerative normocytic normochromic anemia is documented in some dogs with chronic inflammatory enteropathy (CIE), but iron deficiency anemia (IDA) is rare. Decreased reticulocyte hemoglobin (Retic-HgB) concentration is an indicator of iron-deficient erythropoiesis (IDE), which precedes the development of IDA.

Objectives: To investigate the occurrence of IDE in canine CIE by routine hematological parameter assessment including blood Retic-HgB concentrations. Animals: 156 pet dogs with CIE (43 with protein-losing enteropathy [PLE]), 34 dogs with portosystemic shunt (PSS, disease-controls), and 50 blood donors (healthy controls).

Methods: Retrospective case-control study, including patient and clinicopathologic data extracted from electronic medical records. Results of Retic-HgB and other variables were compared and tested for possible associations with clinical and clinicopathologic variables. Delta-HgB was calculated as [(Retic-HgB in pg) - (MCH in pg)].

Results: 13% of dogs with CIE were anemic (PLE: 37%, non-PLE: 4%), but erythrocyte indices were not different from healthy dogs. Retic-HgB concentrations in CIE patients differed significantly from PSS but not from healthy controls, and correlated with MCH (ρ=0.55), MCV (ρ=0.43), and reticulocyte count (ρ=0.28). Retic-HgB concentrations did not differ between PLE and non-PLE cases, regardless of anemia presence, but PLE dogs had higher platelet counts (P=0.0002), erythrocytes of smaller volume (P=0.0246) and less hemoglobin (P=0.0008), and less frequently a negative delta-HgB. Conclusions and clinical importance: The overall prevalence of IDE was low (8%) in CIE patients in this study. However, an iron-restricted state appears more common in PLE cases, which highlights the need to monitor these cases and carefully consider iron supplementation.