Professor of Internal Medicine Iowa State University Ames, AL, United States
Abstract:
Background: Definitive diagnosis of feline chronic enteropathies (CE), i.e., food-responsive enteropathy (FRE), steroid-responsive enteropathy (SRE), and intestinal small cell lymphoma (SCL) is difficult. Leukocyte ratios have been investigated as easily attainable and cost-effective markers of chronic gastrointestinal inflammation in humans and dogs. Their role in the diagnosis of feline CE has not been reported.
Aims: To compare the blood neutrophil-to-lymphocyte (NLR), neutrophil-to-monocyte (NMR), and lymphocyte-to-monocyte (LMR) ratios in healthy cats (HC) and cats with FRE, SRE, and SCL, and to investigate the performance of these ratios as discriminative biomarkers. Animals: Multi-institutional retrospective analysis of healthy cats (n=73) and cats diagnosed with FRE (n=59), SRE (n=56), and SCL (n=33) from 2010-2022.MethodsNeutrophil, lymphocyte, and monocyte counts were extracted from the routine hematological profiles of all cats. NLR, NMR and LMR were calculated and compared by Mann-Whitney U tests. ROC curves investigated the performance of these ratios as biomarkers at the p <0.05 level of significance.
Results: SCL group (median:8.26; range:0.57-94.71) had higher NLR compared to the SRE (median:4.84; range:0.85-44.60;p=0.0024) and FRE (median:3.64;range:0.53-113.00;p=0.028) groups. SCL group (median:2.47;range:0.28-100.00) had lower LMR compared to the SRE (median:6.00;range:0.67-88.00;p=0.012) and FRE (median:8.32;range:0.50-60.13;p=0.001) groups. HC had lower NLR (median:2.24;range:0.38-40.00) compared to the FRE, SRE, and SCL groups (all p p<0.001). AUCs differentiated SCL from SRE using NLR (0.65,CI:0.52-0.77) and LMR (0.66,CI:0.54-0.79) and FRE from SRE using NMR (0.61,CI:0.51-0.71).
Conclusions: The NLR, NMR and LMR may serve as biomarkers for differentiating phenotypes of feline CE.
