Effect of major versus minor mastectomy on host immunity in canine mammary cancer.

Surgical procedures can affect host immunity proportionally to the extent of surgical trauma. In cancer cases, surgery-induced immunosuppression can potentially promote tumour metastasis. The aim of this study was to investigate, in bitches with malignant mammary tumours, whether major surgery (total unilateral mastectomy or bilateral regional mastectomy) has a more negative effect than minor surgery (unilateral regional mastectomy) on components of host immunity. Twenty bitches with mammary cancer of clinical stage II or III were allocated to group A (minor surgery) or group B (major surgery) of 10 animals each receiving the same anaesthetic protocol for mastectomy. Immune cell measurements in blood [number of leukocytes, neutrophils, lymphocytes and platelets, and relative percentages of T-lymphocytes (CD3+) and their CD4+, CD8+ and CD5low+ subpopulations] were performed before anaesthesia (day 0) and on days 3 and 10 post-mastectomy. On day 3, leukocytes, neutrophils and platelets numbers were higher (p = 0.016, 0.032 and 0.017, respectively) in group B than in group A. For all 20 bitches, T-lymphocytes and the CD4+, CD5low+ T-cells were significantly decreased on day 3, but no significant differences were noted between groups. Minor mastectomy seemed to preserve innate immunity better than major mastectomy, but cellular immunity was rather equally affected.

Effect of anaesthesia on cell-mediated immunity in dogs undergoing mastectomy for mammary cancer.

OBJECTIVE: To investigate if anaesthesia for canine cancer mastectomy further influences host cell-mediated immunity (CMI) promoting cancer progression. STUDY DESIGN: A randomized, controlled, blinded clinical study. ANIMALS: A total of 20 bitches with malignant mammary tumours of clinical stage II or III undergoing the same type of mastectomy (regional mastectomy). METHODS: Dogs were randomly allocated to one of two anaesthetic groups (10 per group). The anaesthetic protocol of group A used minimally immunosuppressive drugs (tramadol, robenacoxib, propofol), whereas that of group B (control) used more immunosuppressive drugs (morphine, fentanyl, thiopental, isoflurane). For each animal, measurements of white blood cells (WBCs), neutrophils and lymphocytes, and flow cytometric assessment of T cells (CD3+), helper T cells (CD4+), cytotoxic T cells (CD8+) and CD5low+ T cells were performed prior to anaesthesia (day 0) and on days 3 and 10 postsurgery. Data were analysed using a General Linear Model for repeated measures and presented as mean ± standard deviation, p ≤ 0.05. RESULTS: In all animals, on day 3, WBCs and neutrophils were significantly increased (p < 0.0005), while flow cytometry revealed significantly decreased relative percentages of T cells (CD3+) (p = 0.003) and their subpopulations CD4+ (p = 0.006), CD8+ (p = 0.029) and CD5low+ (p = 0.031). Specifically, on day 3, the cytotoxic T cells (CD8+) were significantly decreased (p = 0.05) only in group B, whereas the CD4+ (p = 0.006) and CD5low+ (p = 0.008) T cells in group A. The only significant difference between groups was found preoperatively in the CD4+/CD8+ ratio, which was higher in group A (p = 0.006). CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with mammary cancer undergoing regional mastectomy, a significant decrease in components of CMI was observed on day 3 postsurgery in both anaesthetic groups. Some indication, however, for better preserved cellular immunity by less immunosuppressive anaesthetic/analgesic drugs was detected, rendering their use advisable.

Diagnostic and prognostic value of peripheral blood leucocyte ratios in sick cats.

The objective of this study was to assess the diagnostic and prognostic utility of feline neutrophil-to-lymphocyte (NLR) and lymphocyte-to-monocyte ratios (LMR) in a variety of underlying diseases. Five-year medical records from cats presenting to the internal medicine unit of a veterinary teaching hospital were retrospectively reviewed. Cats were considered for inclusion based on complete medical records. ADVIA 120 was used for the complete blood counts; the NLR and LMR were calculated by dividing the absolute numbers of the respective leucocytes. Two hundred and nineteen sick and 20 healthy cats were included in the study. The median NLR and LMR were significantly (P < 0.05) elevated and decreased, respectively, in cats with infectious, neoplastic and chronic kidney diseases compared to controls. Additionally, cats with neoplasia had significantly higher median NLR compared to cats with urinary tract and gastrointestinal diseases. Non-survivors had significantly higher NLR and lower LMR compared to survivors. Both ratios had suboptimal prognostic performance for the outcome of sick cats (NLR sensitivity: 37.9%, specificity: 86.4%; LMR sensitivity: 69.0%, specificity: 61.0%). Many different disease categories were associated with increased NLR and decreased LMR compared to controls, but the overall prognostic performance of the two leucocyte ratios was suboptimal.

Circulating and bone marrow myeloid cells containing Leishmania amastigotes in a case of advanced canine leishmaniosis.

A 5-y-old male Poodle mix was presented with intermittent vomiting, anorexia, and weight loss. Physical examination revealed emaciation, lethargy, dehydration, hypothermia, respiratory distress, and splenomegaly. Based on clinicopathologic, serologic, and parasitologic findings, diagnoses of severe leishmaniosis and dirofilariasis were made. Extracellular, intraneutrophilic, and intramonocytic Leishmania amastigotes were observed on blood smear and buffy coat smear examination. In blood smears, 0.2% of neutrophils were observed to be infected; in buffy coat smears, 0.5% of neutrophils and 0.1% of monocytes were found to be infected. Leishmania amastigotes were also found engulfed by eosinophils and neutrophil precursors in bone marrow aspiration cytology. The detection of Leishmania amastigotes in blood smears is rare, and the clinical significance is uncertain. In circulating blood, Leishmania amastigotes are primarily found phagocytized by neutrophils. Although debatable, there is growing evidence that neutrophils are used as carriers enabling the "silent entry" of the protozoa into macrophages ("Trojan horse" theory). To date, cytologic screening of blood smears for the diagnosis of canine leishmaniosis is not a routine practice. Clinical pathologists and practitioners should be aware that Leishmania amastigotes may be present in neutrophils and less frequently monocytes during blood smear evaluation; neutrophil precursors and eosinophils may also be parasitized in bone marrow specimens.

The effect of subchronic oral exposure to zearalenone on hematologic and biochemical analytes, and the blood redox status of adult rabbit bucks.

BACKGROUND: Zearalenone (ZEN) is a mycoestrogen with a ubiquitous presence in animal feeds, which also has hematotoxic, hepatotoxic, nephrotoxic, and immunotoxic properties. However, there is a paucity of literature that discusses the effects of ZEN on rabbits. OBJECTIVES: The aim of this study was to evaluate the effect of a prolonged, low-level (50 µg ZEN/kg body weight) exposure on the clinicopathologic and redox status analytes of rabbit bucks. METHODS: Ten adult bucks were included in the study. Each underwent a 7-week control period, followed by a 7-week exposure period. Water or ZEN solutions were daily administered orally (0.5 mL) during the control and exposure periods, respectively. Blood samples were collected weekly for Complete Blood Counts, serum biochemical analyte and reactive oxygen metabolite (ROM) measurements. Data were analyzed using a mixed model, and the level of significance was set at a P of <0.05. RESULTS: During the ZEN exposure period, significant increases were noted in the red blood cell distribution width (RDW) and mean platelet volumes (MPVs), as well as in the white blood cell, monocyte, and eosinophil counts. Significant increases were observed in aspartate aminotransferase and total bilirubin, whereas urea, creatinine, glucose, total calcium, sodium, and potassium concentrations were significantly decreased. The ROM concentrations did not differ significantly between the control and ZEN exposure periods. CONCLUSIONS: Under the present experimental conditions, ZEN affected some of the clinicopathologic analytes of adult rabbit bucks; these changes were mostly indicative of mild hepatocellular damage and dysfunction, inflammatory and/or allergic responses, and renal tubular damage. A ZEN dose of 50 µg/kg body weight did not seem to affect the blood redox status of bucks, as evaluated by the ROM concentrations.

Evaluation of blood T-lymphocyte subpopulations involved in host cellular immunity in dogs with mammary cancer.

Cancer-bearing patients are often immunosuppressed. In dogs with mammary or other cancers, various alterations in blood cell populations involved in host cellular immunity have been reported; among these cell populations some T-lymphocyte subsets play an important role against cancer. The purpose of the present study was to investigate any alterations in circulating T-lymphocyte subpopulations involved in cellular immunity in bitches with mammary cancer, in comparison to age-matched healthy intact bitches. Twenty eight dogs with mammary cancer and 14 control dogs were included in this study. Twelve out of the 28 bitches had mammary cancer of clinical stage II and 16/28 of stage III. Histological examination revealed that 23/28 animals had carcinomas, 3/28 sarcomas and 2/28 carcinosarcomas. White blood cell, neutrophil and lymphocyte absolute numbers were measured by complete blood count. Furthermore, blood T-lymphocyte population (CD3+) and the subpopulations CD4+, CD8+ and CD5low+ were assessed by flow cytometry. White blood cell and neutrophil but not lymphocyte absolute numbers were higher (P=0.003 and P=0.001, respectively) in cancer patients than controls. Flow cytometric analysis revealed that the relative percentage of T-lymphocytes (CD3+) and of CD4+, CD8+ subpopulations was lower (the CD4+/CD8+ ratio was higher), whereas the percentage of CD5low+ T-cells was higher, in dogs with cancer compared to controls; however, a statistically significant difference was found only in the case of CD8+ T-cells (P=0.014), whereas in the case of the CD4+/CD8+ ratio the difference almost reached statistical significance (P=0.059). Based on these findings, it can be suggested that, although the absolute number of blood lymphocytes is unchanged, the relative percentages of T-lymphocyte subpopulations involved in host cell-mediated immunity are altered, but only cytotoxic CD8+ T-cells are significantly suppressed, in dogs with mammary cancer of clinical stage II or III compared to age-matched healthy controls.

Nodular granulomatous glossitis as the sole clinical sign in canine leishmaniosis.

A 5.5-year-old, intact male Rottweiler dog was admitted with a history of multifocal nodular tongue lesions which progressively deteriorated during the previous year. Physical examination revealed several reddish nodules with central depression on the surface of the tongue in an otherwise healthy dog. Clinicopathologic abnormalities included eosinophilia and hyperproteinemia. Lingual nodule cytopathology, histopathology, and immunohistochemistry revealed Leishmania spp. amastigotes and a severe granulomatous glossitis. The dog was also seroreactive to L infantum antigens by an indirect immunofluorescence assay. Clinical reevaluation 3 months after the institution of treatment with allopurinol and miltefosine indicated that the nodular lesions had completely regressed. In endemic areas, lingual nodular lesions may rarely be the sole clinical sign of canine leishmaniosis. Standard medical treatment may provide an excellent prognosis.

Reference values and repeatability of buccal mucosal bleeding time in healthy sedated cats.

Bleeding time is a screening test for the evaluation of primary haemostasis. As there is currently limited information on the reference interval (RI) and repeatability of the test in the cat compared with the dog, the purpose of the study was to establish the RI of buccal mucosa bleeding time (BMBT) in healthy cats and to investigate the intra-observer repeatability of the test. Fifty-six cats were prospectively enrolled in the study. The animals were deemed to be healthy based on history, physical examination, complete blood count, serum biochemistry, and negative serological testing for feline leukaemia and immunodeficiency viruses. All cats were sedated with ketamine, dexmedetomidine and morphine, and the BMBT was sequentially measured in the left and right exposed buccal mucosa following a standardised incision made by a commercially available, disposable, bleeding time device. The mean BMBT was 58.6 s and the RIs ranged from 34 to 105 s (Bootstrap estimation). The intra-observer repeatability was up to 87 s (Bland-Altman plot). The results of this study imply that the combination of ketamine, dexmedetomidine and morphine is a safe and useful sedative protocol allowing for the reliable measurement of BMBT in the cat. The RI of feline BMBT may range from 34 to 105 s and the BMBT may differ by up to 87 s for any two consecutive readings for an individual cat.

Efficacy of rifampicin in the treatment of experimental acute canine monocytic ehrlichiosis.

OBJECTIVES: To assess the efficacy of rifampicin in achieving clinical and haematological recovery and clearing infection in dogs with experimentally induced acute monocytic ehrlichiosis. METHODS: Five Ehrlichia canis-infected Beagle dogs were treated with rifampicin (10 mg/kg/24 h orally for 3 weeks), nine E. canis-infected dogs received no treatment (infected untreated dogs) and two dogs served as uninfected controls. Clinical score, platelet counts, immunofluorescent antibody titres and PCR detection of E. canis-specific DNA in blood, bone marrow and spleen aspirates were evaluated on post-inoculation days 21 (start of rifampicin), 42 (end of rifampicin) and 98 (end of the study). RESULTS: By day 21 post-inoculation, all infected dogs became clinically ill and thrombocytopenic, seroconverted and were PCR positive in at least one tissue. Clinical scores and antibody titres did not differ between the treated and infected untreated dogs throughout the study. The rifampicin-treated dogs experienced an earlier resolution of their thrombocytopenia (Kaplan-Meier survival plot, P=0.048), and the median platelet counts were significantly higher in the treated compared with the infected untreated dogs on post-inoculation days 42 (P=0.0233) and 98 (P=0.0195). At the end of the study, three treated and six untreated infected dogs remained PCR positive in one tissue each. CONCLUSIONS: The rifampicin treatment regimen applied in this study hastened haematological recovery, but was inconsistent in eliminating the acute E. canis infection.

Presumptive pure erythroid leukemia in a dog.

A 6.5-year-old, intact male Cocker Spaniel dog was referred with a history of depression and anorexia of 1-week duration. Mucosal pallor was prominent on physical examination. Complete blood cell count revealed pancytopenia and occasional blast cells. Bone marrow aspirate cytology indicated that individual particles were composed of approximately 60% hematopoietic cells and a monomorphic population of blast cells with perfectly round nuclei, consistent paranuclear clearing, and deeply basophilic cytoplasm devoid of granules dominating the marrow fields. The granulocytic lineage was severely decreased with a granulocytic-to-erythroid ratio of 0.15 and a blast cell percentage of at least 70% of all nucleated cells; the myeloblasts and monoblasts composed <5% of nonerythroid cells. Bone marrow cytology slides were submitted for immunocytochemical immunophenotyping using antibodies to myeloperoxidase, cluster of differentiation (CD)3, CD79a, CD11b, CD45, and CD34. The neoplastic cells did not express any of the antigens assessed. The combination of light microscopic cytomorphology and the immunophenotype were strongly suggestive of pure erythroid leukemia.

Canine bronchomalacia: a clinicopathological study of 18 cases diagnosed by endoscopy.

Canine bronchomalacia (BM) is characterized by weakness leading to collapse of the bronchial wall. A prospective study of 18 affected dogs (age range: 1-15 years) was undertaken to characterize the clinicopathological and histological features of BM. Poodles and Yorkshire terriers were commonly affected. Half of the dogs were overweight or obese. The clinical presentation was a mild, wheezing, chronic cough and pulmonary crackles were heard in 28% of the dogs. Compatible radiographic changes were present in 61% of the dogs. Using bronchoscopy, both lungs were affected in half of the animals, whereas in the others the disease appeared to affect predominantly the left lung. Analysis of bronchoalveolar lavage fluid and biopsies of bronchial mucosa revealed pure or mixed neutrophilic inflammation. Underlying infectious bronchitis was considered possible in 56% of the dogs. It was concluded that canine BM may present as an isolated clinical entity associated with infection and/or inflammation.