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Background: Glycemic variability (GV) is an indicator of glycemic control and can be evaluated by calculating the SD of blood glucose measurements. In humans with diabetes mellitus (DM), adding a glucagon-like peptide-1 (GLP-1) analogue to conventional therapy reduces GV. In diabetic cats, the influence of GLP-1 analogues on GV is unknown. Objective: To evaluate GV in diabetic cats receiving the GLP-1 analogue exenatide extended release (EER) and insulin. Animals: Thirty client-owned cats with newly diagnosed spontaneous DM. Methods: Retrospective study. Blood glucose curves from a recent prospective placebo-controlled clinical trial generated 1, 3, 6, 10, and 16 weeks after starting therapy were retrospectively evaluated for GV. Cats received either EER (200 μg/kg) or 0.9% saline SC once weekly, insulin glargine and a low-carbohydrate diet. Mean blood glucose concentrations were calculated and GV was assessed by SD. Data were analyzed using nonparametric tests. Results: In the EER group, GV (mean SD [95% confidence interval]) was lower at weeks 6 (1.69 mmol/L [0.9-2.48]; P = .02), 10 (1.14 mmol/L [0.66-1.62]; P = .002) and 16 (1.66 mmol/L [1.09-2.23]; P = .02) compared to week 1 (4.21 mmol/L [2.48-5.93]) and lower compared to placebo at week 6 (3.29 mmol/L [1.95-4.63]; P = .04) and week 10 (4.34 mmol/L [2.43-6.24]; P < .000). Cats achieving remission (1.21 mmol/L [0.23-2.19]) had lower GV compared to those without remission (2.96 mmol/L [1.97-3.96]; P = .01) at week 6. Conclusions and clinical importance: The combination of EER, insulin, and a low-carbohydrate diet might be advantageous in the treatment of newly diagnosed diabetic cats.

Objectives The aims of this study were to validate a commercially available chemiluminescent assay for measurement of feline plasma adrenocorticotropic hormone concentration (ACTH), to determine the normal reference interval (RI) of plasma ACTH in healthy cats, to assess plasma ACTH in cats with naturally occurring hypercortisolism (HC), primary hypoadrenocorticism (PH) and other diseases (OD), and to evaluate the effect of aprotinin on plasma ACTH degradation. Methods Forty healthy cats, 10 with HC, 11 with PH and 30 with OD, were included. The chemiluminescent enzyme immunometric assay was evaluated by measurement of intra-assay precision, interassay precision and linearity. The RI for plasma ACTH in healthy cats was established using robust methods. Plasma ACTH of samples collected with and without aprotinin, stored at 4°C and assayed over a 6-day period, was measured. Results The intra-assay coefficients of variance (CVs) ranged from 2.7% to 4.3% and interassay CVs from 3.3% to 10.7%. Dilution studies showed excellent accuracy (R2 >0.99). The RI for plasma ACTH in healthy cats was 32–370 pg/ml. Plasma ACTH was not significantly different between healthy cats and the OD group. Cats with pituitary-dependent hypercortisolism (PDH) and PH had significantly higher plasma ACTH than the other groups. Plasma ACTH did not show significant differences when samples collected with and without aprotinin were compared. Conclusions and relevance The Immulite chemiluminescent assay is a valid technique for measuring plasma ACTH in cats and the RI of plasma ACTH is quite wide. Owing to the low overlap between healthy or OD cats and cats with HC or PH, the measurement of plasma ACTH appears to be useful and should be included in the diagnostic work-up when HC or PH are suspected. Furthermore, the measurement of plasma ACTH may be an accurate test for differentiating PDH from adrenal-dependent hypercortisolism.

Background Exenatide extended release (ER) is a glucagon-like peptide-1 analogue that increases insulin secretion, inhibits glucagon secretion and induces satiation in humans with type 2 diabetes mellitus. The use of exenatide ER is safe and stimulates insulin secretion in healthy cats. Objectives The objective of this study is to assess the safety of exenatide ER and its effect on body weight, remission and metabolic control in newly diagnosed diabetic cats receiving insulin and a low-carbohydrate diet. Animals Thirty client-owned cats. Methods Prospective placebo-controlled clinical trial. Cats were treated with exenatide ER or 0.9% saline, administered SC, once weekly. Both groups received insulin glargine and a low-carbohydrate diet. Exenatide ER was administered for 16 weeks, or in cats that achieved remission it was given for 4 weeks after discontinuing insulin treatment. Nonparametric tests were used for statistical analysis. Results Cats in the exenatide ER and placebo groups had transient adverse signs including decreased appetite (60% vs. 20%, respectively, P = .06) and vomiting (53% vs. 40%, respectively, P = .715). Body weight increased significantly in the placebo group (P = .002), but not in cats receiving exenatide ER. Cats on exenatide ER achieved remission or good metabolic control in 40% or 89%, respectively, whereas in control cats percentages were 20% or 58% (P = .427 and P = .178, respectively). Conclusion and clinical importance Exenatide ER is safe in diabetic cats and does not result in weight gain. Our pilot study suggests that, should there be an additional clinically relevant beneficial effect of exenatide ER in insulin-treated cats on rate of remission and good metabolic control, it would likely approximate 20% and 30%, respectively.

A 7-month-old male kitten was presented with chronic constipation and retarded growth. Clinical examination revealed disproportional dwarfism with mild skeletal abnormalities and a palpable thyroid gland. The presumptive diagnosis of congenital hypothyroidism was confirmed by low serum total thyroxine (tT4) concentration prior to and after the administration of thyroid stimulation hormone (TSH), increased endogenous TSH concentration and abnormal thyroid scintigraphic scan. The kitten had abnormal liver function tests and decreased insulin-like growth factor 1 (IGF-1) concentration, both of which returned to normal in correspondence with an improvement of the clinical signs after 6 weeks of thyroxine therapy. Congenital hypothyroidism is a rare disease that may present with considerable variation in clinical manifestation. In cases in which clinical signs are ambiguous, disorders such as portosystemic shunt and hyposomatotropism have to be taken into account as differential diagnosis. As hypothyroidism may be associated with abnormal liver function tests and low IGF-1 concentrations, test results have to be interpreted carefully.

The objective of this study was to evaluate the safety and efficacy of insulin glargine in dogs with diabetes mellitus (DM). Twelve client-owned dogs with DM were included. All dogs received insulin glargine every 12 hours for at least six months, re-evaluations were performed after one, two, four, eight, 12 and 24 weeks and included clinical signs, blood glucose curves (BGCs) and measurement of serum fructosamine concentrations. Mean blood glucose concentrations were significantly lower after two weeks of treatment and remained significantly lower for the duration of the study. By week 24, polyuria/polydipsia had improved in 91 per cent of the dogs. No clinical signs that could have been caused by hypoglycaemia were observed. Based on BGCs and remission of the clinical signs for judging the success of the treatment, 58, 33 and 8 per cent of the dogs attained good, moderate and poor glycaemic control by week 24 of the study, respectively. Insulin glargine administered subcutaneously twice daily is a possible and safe method of treatment for dogs with naturally occurring DM. Although only a few studies are available on the use of other types of insulin in dogs, their success rate is somewhat greater than that with insulin glargine.

Background: Hypertension and proteinuria are commonly recognized in dogs with spontaneous hypercortisolism. There is, however, little information regarding the effect of exogenous glucocorticoids on blood pressure (BP) and proteinuria and whether these changes are reversible. Hypothesis: Hydrocortisone administration increases systemic BP and urinary protein excretion, and these effects are reversible after hydrocortisone withdrawal. Animals: Six control dogs and 6 dogs treated with hydrocortisone. Methods: BP, urine protein : creatinine ratio (UPC), microalbuminuria (MALB), urine albumin : creatinine ratio (UAC), and urine gel electrophoresis were evaluated before, during, and after administration of hydrocortisone (8 mg/kg PO q12h for 12 weeks) or placebo. Results: BP and UPC increased substantially during hydrocortisone administration from 123 mmHg (range 114–136 mmHg) and 0.17 (0.15–0.28) to a maximum of 143 mmHg (128–148 mmHg) and 0.38 (0.18–1.78), respectively, on day 28. MALB developed in 4 dogs and UAC significantly increased in all dogs during hydrocortisone administration with the maximum on day 84. Both increases in BP and proteinuria were reversible and completely resolved within 1 month after stopping hydrocortisone administration. SDS-AGE revealed the proteinuria to be primarily albuminuria with a pronounced increase during hydrocortisone treatment. Furthermore, a protein of 25–30 kDa was found in male dogs, identified by mass spectrometry to be arginine esterase, the major secretory prostatic protein. Conclusions and Clinical Importance: Long-term hydrocortisone treatment results in significant but only mild increases in systemic BP and urinary protein excretion, which are both reversible within 1 month after discontinuation of hydrocortisone.