The prevalence of intra-tumoral and distant thrombi, as well as tumour-cell emboli in canine neoplasia.

Macroscopic thromboembolic disease has been associated with canine neoplasia, whereas prevalence studies of concurrent microthrombi and tumour-cell emboli are lacking. This retrospective study investigated microthrombi and tumour cell emboli by reviewing pathology records of dogs diagnosed with lymphoma, sarcoma, carcinoma and mast cell tumours with a concurrent description of thrombi or emboli. Pathology reports and medical records of cases with either tumour biopsies and/or post mortems with a diagnosis of neoplasia were reviewed for the presence of microthrombi, macrothrombi and/or tumour-cell emboli and the association with tumour type. Of the 28 895 canine cases in the database, 21 252 (73.5%) were antemortem biopsy specimens and 7643 were post mortems (26.5%); 2274 solid tumours were identified, 2107 (92.7%) were antemortem biopsy diagnoses and 167 (7.3%) were post mortem diagnoses. The prevalence of solid tumour types in the database (28 895 cases) was 872 (3.0%) lymphoma, 722 (2.5%) sarcoma, 455 (1.6%) carcinoma and 225 (0.8%) mast cell tumour. The prevalence of microthrombi associated with these tumours was 58/2274 (2.6%). Intra-tumoral microthrombi were reported in 53/2274 (2.3%) cases, the majority in sarcomas (37/53, 69.8%). No macrothrombi were reported. Tumour-cell emboli were identified in 39/2274 (1.7%) cases, 31/39 (79.5%) were extra-tumoral or distant emboli, and carcinoma the most commonly associated tumour (29/39; 74.4%). Microthrombi were reported in 2.6% of cases, the majority in sarcomas and tumour-cell emboli were identified in 1.7% of cases, the majority carcinomas. Prospective investigations are necessary to explore the potential clinical and prognostic implications of microthrombi and tumour-cell emboli in canine neoplasia.

Neutrophil Myeloperoxidase Index in Dogs With Babesiosis Caused by Babesia rossi.

Babesiosis caused by the virulent tick-borne hemoprotozoan, Babesia rossi, results in a marked systemic inflammatory host response in dogs. Neutrophils form part of the innate immune response and contains myeloperoxidase (MPO) as the predominant component of the neutrophil lysosomal protein in azurophilic granules. The neutrophil myeloperoxidase index (MPXI), determined on the ADVIA hematology analyzer, is a quantitative estimate of intracellular MPO content. Objectives of this study were to: (a) compare MPXI in dogs with babesiosis with healthy control dogs; (b) compare MPXI in dogs that died from babesiosis with dogs that survived and controls; and (c) correlate the MPXI with the previously determined segmented and band neutrophil count and cytokine concentrations in dogs with babesiosis. Data for 140 dogs naturally infected with B. rossi and 20 healthy control dogs were retrospectively evaluated. Neutrophil counts and MPXI were determined on an ADVIA 2120 analyzer. Cytokine concentrations [interleukin (IL)-2, IL-6, IL-8, IL-10, IL-18, granulocyte-macrophage colony stimulating factor (GM-CSF), and monocyte chemo-attractant protein-1 (MCP-1)] were determined using a canine-specific multiplex immunoassay. The mortality rate of the Babesia-infected dogs was 11% (15/140). MPXI was significantly higher in Babesia-infected dogs (P = 0.033), and in Babesia-infected non-survivors (P = 0.011), compared with healthy control dogs. In Babesia-infected dogs a significant positive correlation was found between MPXI and IL-10 (r = 0.211, P = 0.039) and a significant negative correlation was found between MPXI and IL-8 (r = -0.350, P < 0.001). In Babesia-infected non-survivors, significant positive correlations were found between MPXI and IL-2 (r = 0.616, P = 0.033), IL-6 (r = 0.615, P = 0.033), IL-18 (r = 0.613, P = 0.034), GM-CSF (r = 0.630, P = 0.028), and MCP-1 (r = 0.713, P = 0.009). In Babesia-infected survivors, a significant negative correlation was found between MPXI and IL-8 (r = -0.363, P = 0.001). MPXI was correlated with pro-inflammatory cytokines in Babesia-infected dogs that died. The potential of MPXI as a novel marker of inflammation and prognosis in dogs infected with B. rossi, thus warrants further investigation.