Josep Pastor

Hematological analyses are widely used to assess the health and physiological status of animals, including fish. Automated hematology analyzers enable rapid and reproducible hematological measurements; however, their application in fish requires species-specific analytical validation due to the presence of nucleated blood cells. This study evaluated the analytical performance of the Sysmex XN-1000V hematology analyzer operated under avian settings (PLT-F channel), in juvenile gilthead seabream ( Sparus aurata ), one of the cornerstone species of Mediterranean marine aquaculture. Analytical validation included assessment of precision, linearity, carryover, and sample stability. Results were compared with manual reference methods (hemocytometer counts and blood smear-based estimates). In addition, the influence of two anticoagulants (lithium heparin and K₂EDTA) was examined, and the analyzer’s ability to detect lipopolysaccharide (LPS)-induced changes in non-erythroid cell population was evaluated. The analyzer showed good precision for most parameters (CV < 5%), although higher variability was observed for granulocyte percentage. Linearity was excellent (R ² ≥ 0.98), and carryover remained below 1% for all variables. Sample stability was significantly better at 4 °C than at room temperature (25 °C), supporting refrigerated storage for up to 24 hours prior to analysis. Comparison with manual reference methods revealed strong correlations and agreement for red blood cell counts and hematocrit, whereas discrepancies were identified in non-erythroid cells differentials. Among anticoagulants, lithium heparin yielded more consistent and reliable results than K₂EDTA. Erythrocyte-related parameters showed the highest analytical reliability, whereas the leucocyte differentiation within the non-erythroid fraction required complementary microscopic evaluation, particularly when assessing LPS-induced inflammatory changes. Overall, the Sysmex XN-1000V demonstrated suitable analytical performance for routine hematological assessment in gilthead seabream when operated under avian settings. These findings support its application in aquaculture health monitoring programs, provided that appropriate anticoagulants are used, samples are promptly processed or refrigerated, and automated results are complemented by microscopic review when leukocyte counts are suspected.

Monocytes are key cells of the immune system; various cell subsets have distinct phenotypic characteristics and functions. We characterized canine monocyte subsets in different hematologic disorders by analyzing peripheral blood cells for their expression of CD14 and major histocompatibility complex class II (MHCII). Flow cytometry data of canine blood samples were evaluated retrospectively. We assigned 132 total cases to one of the following categories: healthy, inflammatory, T-zone lymphoma/leukemia (TZL), T-cell chronic lymphocytic leukemia (CLL), B-cell CLL, T-cell stage V lymphoma (SVL), B-cell SVL, acute lymphoblastic or undifferentiated leukemia (ALL/AUL), or acute myeloid leukemia (AML). We analyzed age, sex, breed, light scatter properties, WBC count, CD14 ^pos cells, CD14 ^pos MHCII ^pos cells, CD14 ^pos MHCII ^neg cells, and the CD14 ^pos MHCII ^pos /CD14 ^pos MHCII ^neg ratio. All groups were compared with the healthy group. In healthy dogs, CD14 ^pos MHCII ^pos cells were larger and had a more complex internal structure than CD14 ^pos MHCII ^neg cells. Absolute numbers of CD14 ^pos MHCII ^neg cells were significantly increased in all groups except the TZL and B-cell SVL groups. Absolute numbers of CD14 ^pos MHCII ^pos cells were significantly increased in the T-cell CLL, B-cell CLL, and T-cell SVL groups, mildly increased in the inflammatory and TZL groups, and decreased in the ALL/AUL group. The CD14 ^pos MHCII ^pos /CD14 ^pos MHCII ^neg ratio was markedly decreased in both acute leukemia groups, being pos MHCII ^pos /CD14 ^pos MHCII ^neg ratio has not been identified previously as a hallmark of acute leukemia in dogs.

In dogs, the WDF and WNR scattergrams from the Sysmex XN-1000V enable a highly presumptive interpretation of mastocytemia. This is the first description of abnormal circulating mast cells using the Sysmex XN-1000V, which appears to function similarly to the previous analyzer, the Sysmex XT-2000iV.

Canine lymphoma is a common haematopoietic neoplasm. Immunophenotype is a major prognostic factor and may influence treatment recommendations. This study assessed the diagnostic performance of the Sysmex XN‐1000V white blood cell differential (WDF) scattergram to differentiate canine nodal large B‐cell and T‐cell lymphoma, using the percentage of highly fluorescent cells (%HFC) and visual WDF scattergram evaluation. A retrospective study was conducted on data from cases of cytologically diagnosed canine large cell lymphoma. Cases had concurrent lymph node aspirate cell suspensions in saline that were analysed using the Sysmex XN‐1000V and multiparametric flow cytometry (FC) for lymphoma classification as B or T‐cell. Large B‐cell lymphomas ( n = 86) showed significantly higher %HFC compared to large T‐cell lymphomas ( n = 17), with a median (IQR) of 50% (36–84) and 9.7% (3.9–19), respectively. The ROC analysis showed an AUC of 0.93, with an optimal cutoff of < 24.15 %HFC for identifying T‐cell lymphoma, achieving 88.24% sensitivity, 87.21% specificity, 57.69% PPV and 97.40% NPV. The following data is expressed as ‘overall‐percentage‐agreement (kappa value)’. Using the previous cutoff, the agreement between the %HFC classification and FC was 88.24% ( κ = 0.76). Regarding the WDF scattergram evaluation, the intra‐ and inter‐observer agreement were 86.27% ( κ = 0.71) and 67.65% ( κ = 0.55), respectively. Agreement between the WDF scattergram evaluation and FC was 77.45% ( κ = 0.55), and improved to 90.63% ( κ = 0.74) when just the confident cases were used. In conclusion, a preliminary assessment of the phenotype of canine nodal large cell lymphoma can be made using either the visual inspection of the WDF scattergram or the %HFC. This could serve as a cost‐effective, fast screening tool while awaiting definitive flow cytometry results.

A 12‐year‐old female spayed Border Collie dog was presented for evaluation of 6 months of intermittent hematuria and weight loss. A highly vascularized right renal mass deforming the renal architecture and paraneoplastic hypertrophic osteopathy were found. Cytologic evaluation of the mass obtained by fine‐needle aspiration guided by ultrasound revealed mesenchymal cells with a moderate amount of bluish cytoplasm, moderately defined cell borders, and spindle to stellate or roundish morphology. The nuclei were centrally located, with a coarse chromatin pattern, round to oval, and occasionally bean‐shaped. Usually, a single distinct nucleolus per nucleus with minimal size variation was noted. Anisocytosis and anisokaryosis were moderate. The cytologic interpretation was mesenchymal proliferation with moderate atypia, most consistent with soft tissue sarcoma. Right ureteronephrectomy was performed. Histologic evaluation showed a neoplastic proliferation located beneath the lamina propria of the transitional epithelium of the renal pelvis and infiltrating the renal medulla. Immunohistochemistry for protein S‐100, laminin, and desmin was performed to further characterize the lesion as a nerve sheath tumor. The hematuria disappeared 4 days after the surgery; 5 months later, no alterations were observed in the general examination, and the paraneoplastic hypertrophic osteopathy mildly improved. This is the first cytologic description of a primary renal malignant nerve sheath tumor in the renal pelvis of a dog with paraneoplastic hypertrophic osteopathy.

Hematological studies provide essential information about the health of animals, which is crucial for veterinary medicine, scientific research, and aquaculture. Automatic hematological analyzers are an alternative to manual methods, offering faster and more reliable results. The objective of this study was to validate the Sysmex XN-1000V automatic hematology analyzer for blood samples from rainbow trout (Oncorhynchus mykiss), examine the effects of two anticoagulants (K₂EDTA and lithium heparin), and establish normal blood reference values for this fish species. Additionally, comparative studies were conducted between the Sysmex XN-1000V and manual methods (hemocytometer cell count and blood smear estimation), and reference intervals were established. Ninety-nine heparinized blood samples were analyzed for validation and sample stability tests. The results showed extremely good precision, with a coefficient of variation (CV) below 3% for RBCs, HGB, and HCT and less than 5% for non-RBC cells (leukocytes plus thrombocytes). However, heterophils (%) exhibited higher variability, with a CV of 15.08%. Linearity was excellent, and the carry-over was below 1% for all parameters. The sample stability test indicated that samples could be analyzed for up to 48 h when stored at 4 °C and up to 24 h at room temperature. Non-RBC cells were the first to degrade over time. The automated and manual methods demonstrated good correlation and agreement, validating the analyzer’s accuracy. The effects of two anticoagulants, K₂EDTA and lithium heparin, on the blood samples were also studied. Heparin was the preferred anticoagulant for routine hematological analysis of rainbow trout blood with the Sysmex XN-1000V analyzer. In conclusion, the Sysmex XN-1000V enables complete hemogram analyses to be performed quickly and accurately, standardizing techniques, harmonizing results, and providing reliable reference intervals with O mykiss blood.

Post-transfusion reactions can occur in animals because they present alloantibodies that do not require prior sensitization. Therefore, blood typing is necessary to reduce the risk of hemolytic reactions, but so far, no studies have been carried out to establish the incidence of common blood types in cats from Angola. Therefore, the objective of this observational study was to assess the occurrence of cat blood types in a non-pedigree feline population of Luanda province in Angola, a country in Sub-Saharan Africa, and to determine the risk of a mismatched transfusion and of neonatal isoerythrolysis (NI). Of the 127 cats tested (71 males and 56 females), including diseased and healthy cats with ages ranging from 8 months to 17 years, 94.9% were type A and 5.1% were type B. No type C cats were found. The calculated risk of a mismatched transfusion was 9.64%, and the proportion of mating risk for NI was 4.82%. Our results, although similar to those reported globally, differ from data described in other studies on the African continent. According to the results, blood typing is recommended prior to transfusion or matting.

A 6‐year‐old, intact male English Bulldog presented for evaluation of weakness. Physical examination revealed mildly pale mucous membranes and ophthalmologic alterations. A complete blood cell count was performed on the Urit Smart V5 and the Sysmex XN‐1000V, and showed several hematologic discrepancies between the analyzers. The Urit reported marked leukocytosis and thrombocytosis, and the Sysmex reported marked thrombocytosis on the impedance and optical RET channel but mild thrombocytopenia on the optical PLT‐F channel. On the blood smear examination, there was an abundant proteinaceous material compatible with cryoglobulins. The red blood cell exhibited a notable degree of poikilocytosis. The number of leukocytes was found to be correlated with the Sysmex total white blood cell count, while the platelet count demonstrated a better correlation with the optical PLT‐F channel from the Sysmex. Centrifugation of the blood in a capillary tube (at room temperature) identified a cryoglobulin precipitate. Additionally, the blood was reanalyzed soon after warming it to 37°C, which partially corrected most of the interferences. The serum protein electrophoresis demonstrated a marked hyperproteinemia with mild hypoalbuminemia and a marked hypergammaglobulinemia. On diagnostic imaging, a mild splenomegaly was noted. Cytology of the spleen showed Leishmania infantum infection, plasma cell hyperplasia, and extramedullary hematopoiesis. This is the first description of a dog infected with Leishmania. infantum with concurrent monoclonal hypergammaglobulinemia and cryoglobulinemia. We present a detailed description of the interference of cryoglobulin with the Urit Smart V5 and the Sysmex XN‐1000V, along with the usefulness of Sysmex PLT‐F in this condition.