Evaluation of a low-dose desoxycorticosterone pivalate treatment protocol for long-term management of dogs with primary hypoadrenocorticism.

BACKGROUND: Lowering the dose of desoxycorticosterone pivalate (DOCP) for the treatment of dogs with primary hypoadrenocorticism (PH) decreases costs and could lead to increased owner motivation to treat their affected dogs. OBJECTIVE: To evaluate the efficacy of a low-dose DOCP treatment protocol in dogs with PH. ANIMALS: Prospective study, 17 client-owned dogs with naturally occurring PH (12 newly diagnosed, 5 previously treated with fludrocortisone acetate [FC]). METHODS: Dogs with newly diagnosed PH were started on 1.5 mg/kg DOCP SC; dogs previously treated with FC were started on 1.0-1.8 mg/kg DOCP SC. Reevaluations took place at regular intervals for a minimum of 3 months and included clinical examination and determination of serum sodium and potassium concentrations. The DOCP dosage was adjusted to obtain an injection interval of 28-30 days and to keep serum electrolyte concentrations within the reference interval. RESULTS: Median (range) follow-up was 16.2 months (4.5-32.3 months). The starting dosage was sufficient in all but 2 dogs and had to be significantly decreased after 2-3 months to a median dosage (range) of 1.1 mg/kg (0.7-1.8). Dogs 3 years of age or younger needed significantly higher dosages compared to older dogs. None of them, however, needed the 2.2 mg/kg DOCP dosage, recommended by the manufacturer. CONCLUSIONS AND CLINICAL IMPORTANCE: A starting dosage of 1.5 mg/kg DOCP is effective in controlling clinical signs and serum electrolyte concentrations in the majority of dogs with PH. An additional dose reduction often is needed to maintain an injection interval of 28-30 days. Young and growing animals seem to need higher dosages.

Correlation of plasma coagulation tests and fibrinogenClauss with rotational thromboelastometry parameters and prediction of bleeding in dogs.

BACKGROUND: Correlation of plasma fibrinogen concentration (fibrinogenClauss ) with rotational thromboelastometry (ROTEM) parameters has not been investigated in dogs. OBJECTIVES: To determine the correlation between plasma coagulation tests and fibrinogenClauss with ROTEM parameters and to evaluate their ability to predict bleeding in dogs. ANIMALS: Ninety-seven dogs with concurrent determination of fibrinogenClauss and fibrin polymerization test (FIBTEM) analysis. METHODS: Signalment, pretreatment, clinical signs of bleeding, fibrinogenClauss , plasma coagulation test results, hematocrit, platelet count, FIBTEM, extrinsic (EXTEM) and intrinsic (INTEM) activated ROTEM assays were retrieved retrospectively. Correlations between fibrinogenClauss and FIBTEM maximum clot firmness (MCFFIBTEM ) and between prothrombin time (PT) or activated partial thromboplastin time (aPTT) and ROTEM parameters were determined. Dogs were further assigned to groups with or without clinical signs of bleeding. The prognostic significance of significantly different parameters to predict bleeding was evaluated. RESULTS: FibrinogenClauss showed strong correlation with MCFFIBTEM (r = 0.860, n = 97, P < .001). PT showed strong correlation with EXTEM clotting time (CTEXTEM ) (r = 0.839, n = 53, P < .001), and aPTT was strongly correlated with INTEM CT (CTINTEM ) (r = 0.664, n = 31, P < .001). Platelet count, PT/aPTT, EXTEM clot formation time (CFTEXTEM ), MCFEXTEM , EXTEM maximum clot elasticity (MCEEXTEM ), and CTINTEM were significantly different between groups. A CTINTEM >149 seconds was 100% sensitive to detect bleeding. CONCLUSIONS AND CLINICAL IMPORTANCE: The MCFFIBTEM can be used to evaluate the effect of fibrinogen on hemostasis as an alternative to determination of fibrinogenClauss . In addition, CTEXTEM and CTINTEM are strongly correlated with PT and aPTT, respectively.

Comparison of two prepill cortisol concentrations in dogs with hypercortisolism treated with trilostane.

BACKGROUND: The ideal method for monitoring trilostane therapy in dogs with hypercortisolism is still open to debate. Recently, determination of the pre-trilostane (prepill) cortisol concentration has been proposed to be more repeatable than either post-trilostane or post-ACTH cortisol. The aim of this study was to compare two prepill cortisol concentrations in dogs with hypercortisolism during trilostane therapy. Sixteen client-owned dogs with naturally occurring hypercortisolism were prospectively included and cortisol concentrations were measured twice, 1 h apart, before the morning trilostane dose (prepill 1 and 2 cortisol). RESULTS: A total of 47 prepill cortisol measurement pairs were included. Compared to prepill 1, prepill 2 cortisol was higher in 15, equal in 8 and lower in 24 pairs. Group agreement between prepill 1 and 2 cortisol was 70% (moderate agreement - weighted kappa 0.55). In 30% of the pairs, group assignment was discrepant, implying a different therapeutic decision. In some dogs certain circumstances (e.g. excessive barking, difficulties during blood collection, excitement at arrival) were identified as potential factors explaining the discrepancy between prepill 1 and 2 cortisol measurements. CONCLUSIONS: In a substantial number of dogs treated with trilostane, the two prepill cortisol concentrations differed. Part of this difference might be ascribable to stressful events during test performance. When using prepill cortisol measurements to monitor trilostane therapy, recording of any incident during handling that might affect cortisol release might be helpful to make a reliable decision about a trilostane dose adaptation.