Abstract: Background – Reticulocyte counts (RETIC) are considered the gold standard in detecting an erythroid bone marrow response (BMR) in anemic and non-anemic dogs. Reticulocytosis without anemia (RWA) is a potential indicator of disease. Geographical and breed variations may render differing prevalence of anemia or RWA and differing performance of RBC indices to detect a BMR.
Objective – This study aimed to determine prevalence of anemia, performance of RBC indices to detect a BMR, and prevalence of RWA of dogs in Taiwan.
Animals – Final analysis population consisted of 149,076 dogs.
Methods – A cross sectional, retrospective analysis of CBC samples from ProCyte Dx® hematology analyzers in Taiwan from December 1, 2018 through December 31, 2020, assessed sensitivity and specificity of increased MCV and decreased MCHC (MCV/MCHC) results to detect reticulocytosis.
Results – Among 149,076 dogs included, 11.8% (n=17,600) had reticulocytosis (RETIC > 110K/µl) and 21.8% (n=32,474) had anemia (HCT < 37.3%). Of 32,474 anemic dogs, 17.8% (n=5,789) had reticulocytosis. Of 116,602 dogs without anemia, 10.1% (n=11,776) had reticulocytosis. Sensitivity/specificity of MCV/MCHC to detect BMR was 4.3% and 99.4%, respectively compared to RETIC across all dogs. Among anemic dogs, sensitivity/specificity of MCV/MCHC to detect BMR was 9.6% and 99.2%, respectively. Among non-anemic dogs, sensitivity/specificity of MCV/MCHC to detect BMR was 1.6% and 99.5%, respectively.
Conclusions and clinical importance –Most regenerative anemias and cases of RWA did not have combined increased MCV and decreased MCHC. To avoid overlooking potential illness, RETIC should be evaluated regardless of whether patients have anemia or not.
