Evaluation of hemostatic abnormalities in canine spirocercosis and its association with systemic inflammation

A prospective evaluation of the prevalence of thromboemboli and associated hemostatic dysfunction in dogs with carcinoma or sarcoma

BACKGROUND

Knowledge of the prevalence of thromboemboli and the associated hemostatic status in dogs with carcinoma or sarcoma is unknown and might allow earlier intervention.

OBJECTIVES

Estimate prevalence of thromboemboli and their association with hemostatic changes in dogs with carcinomas or sarcomas; estimate predictive values of hemostatic variables for thromboembolic disease in tumor-bearing dogs.

ANIMALS

Thirty-two dogs with sarcoma, 30 with carcinoma, 20 healthy age-controlled dogs.

METHODS

Prospective cross-sectional study. A hemostasis panel (platelet concentration, thromboelastography, fibrinogen and D-dimer concentration, factor X, VII and antithrombin activity) was performed in all dogs. Tumor-bearing dogs underwent complete post mortem and histopathological evaluation. Comparisons between healthy dogs and tumor-bearing dogs with and without intracavitary hemorrhage; and tumor-bearing dogs with and without microthrombi were analyzed.

RESULTS

Thromboembolic disease was identified in 32/62 (52%, 95% CI: 39%-65%) tumor-bearing dogs. Microthrombi were identified in 31/62 (50%, 95% CI: 37%-63%) dogs, 21/31 (68%, 95% CI: 49%-83%) had exclusively intra-tumoral microthrombi, 10/31 (32%, 95% CI: 17%-51%) had distant microthrombi. Macrothrombi were identified in 3 tumor-bearing dogs. Hemostatic changes potentially consistent with overt and non-overt disseminated intravascular coagulation were identified in some tumor-bearing dogs. D-dimer concentrations were significantly higher (P = .02) and platelet concentration significantly lower (P = .03) in tumor-bearing dogs with microthrombi compared to tumor-bearing dogs without microthrombi. D-dimer concentration above 500 ng/mL was 80% sensitive and 41% specific for the prediction of microthrombi presence.

CONCLUSION

The high microthrombi prevalence and concomitant hemostatic dysfunction in dogs with carcinomas or sarcomas has not previously been reported, though the clinical importance is unknown. Increased D-dimer concentration might increase suspicion of microthrombi.

Spirocerca lupi induced oesophageal neoplasia: Predictors of surgical outcome

Canine spirocercosis is caused by the nematode Spirocerca lupi. Migration results in oesophageal fibro-inflammatory nodules that may undergo neoplastic transformation. No studies have assessed pre- or post-surgical prognostic indicators in dogs that undergo intervention for S. lupi induced oesophageal neoplasia. This observational, multi-center study aimed to assess the outcome of dogs with Spirocerca induced sarcoma undergoing endoscopic-guided ablation (n = 12) or surgery (n = 18), and identify prognostic indicators. Parameters evaluated included: age, weight, gender, presenting complaints, duration of clinical signs, complete blood count, serum biochemistry, neoplasia size, placement of percutaneous endoscopically-placed gastrostomy tube, histopathological mitotic indices, days to discharge and chemotherapy administration. Kaplan-Meier survival curves showed no difference in survival between ablation and surgery {(median: 73.5 days (range: 0-1511) vs. 108 days (range: 0-1550), respectively (p = 0.982)}. Reduced survival was documented in patients presenting with weight loss (P = 0.027), hypochromasia (MCHC <33 g/dL, P = 0.023) or leucocytosis (>15 × 10⁹/L, P = 0.017) with a hazard ratio of 2.51 (CI_95% = 1.071-6.018, P = 0.034), 2.71 (CI_95% = 1.10-6.65, P = 0.03) and 4.39 (CI_95%: 1.21-15.97, P = 0.025) respectively. In the dogs surviving more than 21 days, Ht <36% and leucocytosis >15.0 × 10⁹/L at presentation were associated with reduced survival (p = 0.016, p = 0.021 respectively) and hazard ratio of 3.29 (CI_95% = 1.18-9.2, P = 0.023) and 3.81 (CI_95% = 1.15-12.55, P = 0.028) respectively. Intra-intervention-group survival analysis identified increased survival time in dogs receiving chemotherapy, but only within the surgical group (P = 0.02).The hospitalisation time of dogs undergoing ablation (median: 0 days, range: 0-4) was significantly shorter than dogs undergoing surgery (9 days, 1-21) (P < 0.001). In this study, no clear benefit was identified for surgery, thus when ablation is technically possible it should be considered advantageous, as hospitalisation time is significantly shorter. Weight loss, hypochromasia and leucocytosis were identified as long-term prognostic indicators at presentation.

Assessment of the relationships among coagulopathy, hyperfibrinolysis, plasma lactate, and protein C in dogs with spontaneous hemoperitoneum

OBJECTIVE

To relate coagulation and fibrinolysis derangements to shock severity as reflected by plasma lactate concentrations in dogs with spontaneous hemoperitoneum (SHP) and determine the impact on transfusions.

DESIGN

Prospective, observational, case-control study.

SETTING

Three veterinary teaching hospitals.

ANIMALS

Twenty-eight client-owned dogs with SHP and 28 breed- and age-matched control dogs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Blood samples for platelet counts, coagulation, and anticoagulant assays (prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin, and protein C, thromboelastography [TEG]), fibrinolysis testing (d-dimer and TEG lysis parameters with and without the addition of 50 U/mL of tissue plasminogen activator [TEG LY30 measured with the addition of 50 U/mL of tPA to the blood sample, LY3050 and TEG LY60 measured with the addition of 50 U/mL of tPA to the blood sample, LY6050 ; LY30 and LY60]), and plasma lactate as an indicator of severity of shock were collected from SHP dogs at the time of diagnosis. SHP dogs were hypocoagulable (prolonged prothrombin time and activated partial thromboplastin time, decreased TEG maximum amplitude) and hyperfibrinolytic (increased LY3050 and TEG LY6050 ) compared to controls. The severity of hypocoagulability was related to protein C activity, while the severity of hyperfibrinolysis was related to plasma lactate concentration. Among the 18 dogs discharged from the hospital, LY3050 was significantly associated with the dose of fresh frozen plasma administered, but none of the parameters were associated with the dose of red blood cells administered.

CONCLUSIONS

Dogs with SHP have evidence of hypocoagulability, protein C deficiency, and hyperfibrinolysis. Parameters of hyperfibrinolysis were related to plasma lactate concentrations and volume of plasma transfused during hospitalization. These derangements resemble those found in people with acute coagulopathy of trauma and shock, and activation of protein C may be a common feature to both syndromes.