PTH and primary hyperparathyroidism: One dog was subsequently diagnosed with primary hyperparathyroidism at the same visit based on ionized hypercalcemia and high-normal parathyroid hormone (PTH) concentration (ionized calcium 1.66 mmol/L, reference range 1.25–1.45; PTH 4.0 pmol/L, reference range 0.5–5.8; and PTH-related protein 0.0 pmol/L, reference range 0.0–1.0).