Calcium and phosphate homeostasis in dogs with newly diagnosed naturally occurring hypercortisolism

Abstract

Background: Hypercortisolism affects calcium and phosphate metabolism in dogs; however, the exact mechanisms are not completely understood. Objectives: To evaluate circulating concentrations of whole parathormone (wPTH), 25-hydroxyvitamin D (25-(OH)D), calcitriol, and fibroblast growth factor-23 (FGF-23) in dogs with naturally occurring hypercortisolism (NOHC) and healthy dogs, and their association with calcium and phosphate homeostasis. Animals: Twenty-three client-owned dogs with NOHC, and 12 client or staff-owned healthy dogs. Methods: Prospective cross-sectional study. The circulating concentrations of total calcium, ionized calcium (iCa), phosphate, wPTH, 25-(OH)D, calcitriol and FGF-23, and the urinary fractional excretion of phosphate (FEP) and calcium (FECa) were compared between dogs with NOHC before treatment and healthy dogs.Results: Dogs with NOHC had higher mean serum phosphate concentrations (4.81 mg/dL, SD ± 0.71 vs 3.86 mg/dL, SD ± 0.60; P < .001), median FECa (0.43%, range, 0.03-2.44 vs 0.15%, range, 0.06-0.35; P = .005), and median serum wPTH concentrations (54.6 pg/mL, range, 23.7-490 vs 24.6 pg/mL, range, 5.5-56.4; P = .003) as compared to the controls. Circulating concentrations of total calcium, iCa, and calcitriol and the FEP did not differ between groups, whereas the serum 25-(OH)D concentrations were lower in dogs with NOHC as compared to the controls (70.2 pg/mL, SD ± 42.3 vs 106.3 pg/mL, SD ± 35.3; P = .02). The dogs with NOHC had lower plasma FGF-23 concentrations than controls (316.6 pg/mL, range, 120.8-575.6 vs 448.7 pg/mL, range, 244.8-753; P = .03).Conclusions and Clinical Importance: Urine loss of calcium and hyperphosphatemia could contribute to the adrenal secondary hyperparathyroidism.

Caracterización clínica y de laboratorio de 131 casos (2016 – 2022) de hipercortisolismo ACTH-dependiente canino

“…Hiperparatireoidismo secundário adrenal é relatado em cães hipercortisolêmicos, sendo sugerido como consequência de alterações no metabolismo de cálcio e fosfato, com hipercalciúria sustentada e hiperfosfatemia podendo ser fatores estimulantes à secreção de PTH, visto que cães com hipercortisolismo apresentaram maiores concentrações médias séricas de fosfato, de fração de excreção urinária de cálcio e de parathormônio total (PTH), apesar de não terem tido diferenças significativas de concentrações de cálcio total ou ionizado, em relação aos cães hígidos (Corsini et al, 2021). Hipercalciúria pode aumentar o risco de desenvolvimento de urólitos contendo cálcio (Behrend, 2015).…”

Біохімічні Показники Сироватки Крові Собак За Гіперадренокортицизму

“…Gilor and Graves повідомляють, що за синдрому Кушинга характерні еритроцитоз та тромбоцитоз, що також знаходить підтвердження у наших дослідженнях [19].…”

Survival of dogs with pituitary‐dependent hyperadrenocorticism treated twice daily with low doses of trilostane

“…Serum phosphate concentrations and parathyroid hormone concentrations in dogs with CS are significantly higher than in healthy dogs. 23,24 This has been hypothesised to be one of the possible mechanisms for the development of soft tissue calcification, and therefore calcinosis cutis. 24 Dogs with PDH treated with trilostane with serum phosphate concentrations >1.45 mmol/L have lower survival times than those with values ≤1.45 mmol/L.…”