Objectives The aim of the study was to evaluate circulating insulin-like growth factor-1 (IGF-1), feline pancreas-specific lipase (fPLI) and total thyroxine (TT4) concentrations and urinary corticoid-to-creatinine ratio (UCCR) as indicators for the prevalence of acromegaly, pancreatitis, hyperthyroidism and hypercortisolism in cats with diabetes mellitus. Methods Blood and urine samples were collected from diabetic cats treated in primary care clinics in Switzerland and the Netherlands. Standardised questionnaires and physical examination forms provided clinical information from owners and veterinarians. Laboratory testing included serum biochemistry profile analysis and measurement of circulating fructosamine, IGF-1, fPLI, and TT4 concentrations and UCCR. CT of the pituitary gland was performed using a multidetector computed tomography scanner. Results Blood samples were available from 215 cats and urine samples were collected at home from 117 cats. Age ranged from 2-18 years (median 12 years) and body weight from 2.7-12.3 kg (median 5.5 kg). Sixty-five percent of the cats were castrated male and 35% were female (33% spayed); 82% were domestic shorthair cats. Eighty percent of cats received a porcine insulin zinc suspension, 19.5% insulin glargine and 0.5% a human neutral protamine hagedorn insulin. Thirty-six of 202 (17.8%) cats had IGF-1 concentrations >1000 ng/ml. Serum fPLI, and TT4 concentrations and UCCR were increased in 86/196 (43.9%), 9/201 (4.5%) and 18/117 cats (15.3%), respectively. Prevalence did not differ between countries. Conclusions Hyperthyroidism is rare, whereas increased fPLI concentration, possibly reflecting pancreatitis, is common in diabetic cats. The high UCCR may reflect activation of the hypothalamus-pituitary-adrenal axis, which also occurs in diabetic humans. The percentage of cats with increased IGF-1 was high but lower than reported in recent studies.

BackgroundThe TSH stimulation test to confirm canine hypothyroidism is commonly performed using a recombinant human TSH (rhTSH), as up to date, canine TSH is not yet commercially available. Limiting factors for the use of rhTSH are its high costs and occasional difficulties in product availability. Less expensive bovine TSH preparations (bTSH) purified from bovine pituitary glands are readily commercially available. The aim of this study was to evaluate two different bTSH products as alternative to rhTSH using mass spectrometry.ResultsMore than 50 proteins, including other pituitary hormones, bovine albumin, hemoglobin, and tissue proteins were identified in the bTSH preparations. In contrast, rhTSH proved to be a highly pure product. Significantly higher endotoxin levels could be detected in all bTSH products compared to the rhTSH.ConclusionsBoth bTSH products are crude mixtures and therefore not an acceptable alternative to rhTSH. Their use should be discouraged to prevent unintended side effects.