Hematologic changes in dogs with non-infectious and vector-borne infectious inflammatory diseases
- Autores: Antonio Meléndez Lazo
- Directores de la Tesis: Laia Solano Gallego (dir. tes.), Josep Pastor Milán (dir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2018
- Idioma: español
- Tribunal Calificador de la Tesis: Maria Grazia Pennisi (presid.), Rafaela Cuenca Valera (secret.), Rafael Barrera Chacón (voc.)
- Programa de doctorado: Programa de Doctorado en Medicina y Sanidad Animales por la Universidad Autónoma de Barcelona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TESEO
- Resumen
Inflammation is common in a large variety of pathologic conditions affecting dogs, including neoplasia, immune-mediated, metabolic and vector-borne diseases. The latter are highly prevalent in our geographic area and are frequently accompanied by several hematologic and biochemical changes that can be detected as part of a first step screening in diagnostic workup. Clinicopathological changes in vector-borne diseases show some discrepancies among studies and information about these changes in some of them is limited. In addition, periodical update of these alterations is desirable following advances in diagnostic techniques and analyzers’ technology.
Reticulocyte parameters have become available in the last years for veterinary medicine. They are provided by many laser-based hematology analyzers that measure reticulocyte, including point-of-care hematological analyzers. These parameters, especially reticulocyte mean hemoglobin content (CHr) and reticulocyte hemoglobin equivalent (Ret-He), are fast, inexpensive and sensitive markers of iron-deficiency in people and dogs. Some studies have also documented the importance of these parameters as markers of inflammation in human medicine. However, limited information is available about reticulocyte parameters in other conditions apart of iron-deficiency in dogs.
Therefore, the main objective of this doctoral thesis was to investigate hematologic changes associated with non-infectious and vector-borne inflammatory processes with special emphasis in reticulocyte parameters.
Firstly, in study 1, several reticulocyte parameters in dogs grouped in different etiopathological categories were investigated. A linear positive correlation between C-Reactive Protein (CRP) and reticulocyte volume distribution width (RDWr), percentage of microcytic reticulocytes (%MicroRet) and percentage of reticulocytes with low CHr (%LowCHr) was found. Negative linear correlations were found between CRP and reticulocyte mean volume (rMCV), percentage of macrocytic reticulocytes (%MacroRet), CHr and percentage of reticulocytes with high CHr (%HighCHr). Sick dogs with inflammation demonstrated by high CRP showed higher RDWr and %LowCHr, and lower CHr, %HighCHr and medium and high-fluorescence reticulocytes when compared to sick dogs with normal CRP.
In study 2, hematological parameter including CHr in dogs infected with Mycoplasma haemocanis, Anaplasma phagocytophilum, Ehrlichia canis and Babesia spp. evaluated and compared with the existing literature. The most relevant findings were the presence of decreased CHr in co-infected dogs when compared with dogs infected with M. haemocanis or E. canis alone. Furthermore, a high prevalence of PCR positive dogs for M. haemocanis was found, with the majority of them revealing several hematologic alterations such as non-regenerative anemia, neutrophilic leukocytosis, monocytosis and thrombocytopenia.
Then, canine leishmaniosis (CanL) was the focus of studies 3 and 4. We studied clinicopathological findings in dogs with CanL at the time of diagnosis and evaluated the different clinical classification systems proposed on the literature. Hematologic and serum biochemistry alterations were similar to those previously described but, interestingly, azotemia was rare in contrast to previous studies, although proteinuria was common, indicating glomerular damage but preserved renal function. When dogs were classified among all the studied classification systems in categories of mild, moderate and severe disease, the agreement was poor, with only 3 out of 51 dogs classified at the same category for all classification systems. This disagreement may lead to different treatment and follow-up regimens depending on the classification system used.
Finally, the utility of reticulocyte indices at the time of diagnosis and during one- year treatment follow-up in dogs with CanL was studied. Additionally, inflammation and oxidative stress were assessed through the measurement of CRP, ferritin, haptoglobin and paraoxonase-1. Although sick dogs showed lower CHr than control dogs, changes in reticulocyte parameters were of limited utility for diagnosis and treatment monitoring purposes.
In conclusion, we demonstrated changes in reticulocyte parameters in dogs with inflammation and vector-borne diseases and provided an update for clinicopathological changes in various vector-borne diseases.
