Hypercalcaemia in a dog with hypothyroidism.

A 5-year-old, entire, female Greenland dog was presented with polyuria and polydipsia. A mildly increased circulating concentration of ionised calcium, mild non-regenerative anaemia, mild hypercholesterolemia and mild increases in liver enzyme activity were detected. Parathyroid hormone, plasma parathyroid hormone-related protein and vitamin D were analysed in a blood sample, with all results below the lower limit of the reference range. Further investigation with abdominal ultrasonography, fine-needle aspiration for cytology of the liver and spleen, thoracic radiography, adrenocorticotropic hormone-stimulation and serum protein electrophoresis could not detect any disease. During the next months, the dog developed coat changes that clinically corresponded to an endocrinopathy. Analysis of thyroxine and thyroid-stimulating hormone was performed. Thyroxine was less than 6 nmol/L and thyroid-stimulating hormone was 1.5 µg/L, which indicated primary hypothyroidism. Treatment with l-thyroxine resulted in normalisation of the hypercalcaemia. Moreover, the polyuria and alopecia resolved. [ABSTRACT FROM AUTHOR]