Evaluation of reticulocyte hemoglobin content in dogs affected by neoplastic disease

Background. Reticulocyte hemoglobin (RETIC-HGB) is a parameter provided by hematology analyzer that has recently been shown to be valuable for the early diagnosis of iron deficiency anemia. Furthermore, in human medicine it has been proposed that reticulocyte hemoglobin content may represent an easy diagnostic tool for monitoring iron deficiency anemia in patients with neoplastic disease undergoing chemotherapy. Objectives. To assess the correlation between total iron and RETIC-HGB and to evaluate the relationship between RETIC-HGB and erythroid parameters in dogs affected by various types of neoplasia. Materials and Methods. 153 CBCs were performed in a different group of dogs (43 not anemic/RETIC-HGB normal; 50 not anemic/RETIC-HGB reduced; 60 anemic) to assess the correlation with total serum iron. Also, 354 CBCs were performed by ProCyte DX (IDEXXTM) from 121 dogs with neoplastic disease: 31 epithelial, 58 discrete round cell, 19 mesenchymal and 13 other. Results. RETIC-HGB shows a significant correlation with iron levels in the overall study population (p < 0.0001) as well as in the subgroup of anemic subjects (p=0.0004). Reduced RETIC-HGB was observed in 38.54% of CBCs from patients with neoplastic disease. A correlation was observed between RETIC-HGB and RBC (r=0.13; p=0.0195), Hct (r=0.23; p=0.0001), Hb (r=0.28; p<0.0001), MCV (r=0.41; p<0.0001), MCH (r=0.69; p<0.0001), MCHC (r=0.39; p<0.0001), RDW (r=-0.24; p<0.0001). Conclusions. The correlation between RETIC-HGB in neoplastic subjects is stronger against erythrocyte indices which are related to iron content and especially to MCH. RETIC-HGB can be considered a marker for the early diagnosis of iron-deficiency erythropoiesis in anemic subjects and is a useful tool for pre-chemotherapy assessment.