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Cross-linked chitosan iron (III) is a chitin-derived polymer with a chelating effect on phosphorus, but it is untested in vascular calcification. We evaluated this compound's ability to reduce hyperphosphatemia and its effect on vascular calcification in uremic rats using an adenine-based, phosphorus-rich diet for seven weeks. We used a control group to characterize the uremia. Uremic rats were divided according the treatment into chronic kidney disease, CKD-Ch-Fe(III)CL (CKD-Ch), CKD-calcium carbonate, or CKD-sevelamer groups. We measured creatinine, phosphorus, calcium, alkaline phosphatase, phosphorus excretion fraction, parathyroid hormone, and fibroblast growth factor 23. Vascular calcification was assessed using the aortic calcium content, and a semi-quantitative analysis was performed using Von Kossa and hematoxylin-eosin staining. At week seven, rats in the chronic kidney disease group had higher creatinine, phosphorus, phosphorus excretion fraction, calcium, alkaline phosphatase, fibroblast growth factor 23, and aortic calcium content than those in the Control group. Treatments with cross-linked chitosan iron (III) and calcium carbonate prevented phosphorus increase (20%-30% reduction). The aortic calcium content was lowered by 88% and 85% in the CKD-Ch and CKD-sevelamer groups, respectively. The prevalence of vascular changes was higher in the chronic kidney disease and CKD-calcium carbonate (62.5%) groups than in the CKD-Ch group (37.5%). In conclusion, cross-linked chitosan iron (III) had a phosphorus chelating effect similar to calcium carbonate already available for clinical use, and prevented calcium accumulation in the aorta. Impact statement Vascular calcification (VC) is a common complication due to CKD-related bone and mineral disorder (BMD) and is characterized by deposition of calcium in vessels. Effective therapies are not yet available but new phosphorus chelators can prevent complications from CV. We tested the effect of chitosan, a new phosphorus chelator, on the VC of uremic animals. It has recently been proposed that chitosan treatment may be effective in the treatment of hyperphosphataemia. However, its action on vascular calcification has not been investigated yet. In this study, we demonstrated that chitosan reduced the calcium content in the aorta, suggesting that this may be a therapeutic approach in the treatment of hyperphosphatemia by preventing CV.

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Background: Chronic kidney disease (CKD) is a very common pathology in cats, especially in the geriatric age. A proper renal diet is considered the current standard of care to enhance patients long-term survival and quality of life. However, when diet alone is not sufficient, it is necessary to supplement it with specific substances: these are phosphate binders and alkalinizing agents. The aim of this study was to evaluate the effectiveness of a feed supplement containing calcium carbonate, calcium lactate gluconate, chitosan and sodium bicarbonate in controlling hyperphosphatemia and metabolic acidosis in cats with severe CKD (IRIS, International Renal Interest Society, stage 3 and 4). Materials, Methods & Results: 10 cats (median BW 4.00 (3.20; 5.70) Kg, BCS 3/5 (2.25; 3.75), 11 (8.25;12.00) years) fed with a balanced renal diet were included in the study. To be enrolled in the study cats had to be affected by CKD in stages 3 or 4 and show hyperphosphatemia. Treatment consisted in oral administration of the product (Renal, Candioli Pharma) at 0.2 g/kg/day mixed with the food for 60 days. The animals were evaluated at the beginning of the study and at 15, 30, 60 days (T0, T15, T30, T60) for: clinical condition, BW, BCS, blood pressure and for routinely hematochemical, biochemical and urinary parameters. Owners were asked to assess appetite of the cat, palatability of the [...](AU)

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Background: Chronic kidney disease (CKD) is a very common pathology in cats, especially in the geriatric age. A proper renal diet is considered the current standard of care to enhance patients long-term survival and quality of life. However, when diet alone is not sufficient, it is necessary to supplement it with specific substances: these are phosphate binders and alkalinizing agents. The aim of this study was to evaluate the effectiveness of a feed supplement containing calcium carbonate, calcium lactate gluconate, chitosan and sodium bicarbonate in controlling hyperphosphatemia and metabolic acidosis in cats with severe CKD (IRIS, International Renal Interest Society, stage 3 and 4). Materials, Methods & Results: 10 cats (median BW 4.00 (3.20; 5.70) Kg, BCS 3/5 (2.25; 3.75), 11 (8.25;12.00) years) fed with a balanced renal diet were included in the study. To be enrolled in the study cats had to be affected by CKD in stages 3 or 4 and show hyperphosphatemia. Treatment consisted in oral administration of the product (Renal, Candioli Pharma) at 0.2 g/kg/day mixed with the food for 60 days. The animals were evaluated at the beginning of the study and at 15, 30, 60 days (T0, T15, T30, T60) for: clinical condition, BW, BCS, blood pressure and for routinely hematochemical, biochemical and urinary parameters. Owners were asked to assess appetite of the cat, palatability of the [...]

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OBJETIVO: Descrever a frequência de prescrição de quelantes de fósforo (QF) e calcitriol em pacientes sob hemodiálise (HD) crônica em Salvador, Brasil, e avaliar se o tratamento está de acordo com recomendações do Kidney Disease Outcomes Quality Initiative (K/DOQI). MÉTODOS: Corte transversal de dados da linha de base do Estudo Prospectivo do Prognóstico de Pacientes Tratados Cronicamente por Hemodiálise (PROHEMO). Foi realizada descrição da frequência de prescrição de QF e calcitriol conforme as concentrações de indicadores laboratoriais do metabolismo mineral, comparando com recomendações do K/DOQI. RESULTADOS: Sevelamer isoladamente (i.e., não combinado com outro QF) foi prescrito para 45,4 por cento dos pacientes, carbonato de cálcio (CaCO3) isoladamente para 26,5 por cento, sevelamer combinado com CaCO3 para 2,1 por cento e acetato de cálcio para 5,2 por cento. Prescrição de QF foi observada para 53 por cento dos pacientes com fósforo <3,5 mg/dL e 40 por cento com fósforo <3,0 mg/dL. Em desacordo com K/DOQI, prescrição de calcitriol foi detectada para 19 por cento dos pacientes com PTH<150 pg/mL e ausência da prescrição para aproximadamente 35,4 por cento com PTH>300 pg/dL combinado com fósforo menor ou igual a 5,5 mg/dL, cálcio menor ou igual a 9,5 mg/dL e produto cálcio e fósforo (CaxP)<55 mg2/dL2. Neste último grupo, 38 por cento tiveram prescrição de sevelamer sem outro QF. CONCLUSÃO: Os resultados mostram um elevado percentual de prescrição de sevelamer em pacientes em HD de manutenção em uma cidade brasileira, apesar do alto custo deste medicamento e ausência de contraindicação para QF à base de cálcio. Os resultados em pacientes com PTH<150 pg/mL e com PTH>300 pg/mL combinado com determinadas concentrações de cálcio, fósforo e CaxP indicam também a necessidade de avaliar as práticas de uso de QF e calcitriol.

OBJECTIVE: To describe the frequency of prescription of phosphate binders (PB) and calcitriol for patients on chronic hemodialysis in Salvador, Brazil, and to assess whether treatment is in agreement with recommendations of the Kidney Disease Outcomes Quality Initiative (K/DOQI). METHODS: Cross section of baseline data of the PROHEMO study. The frequency of prescription of PB and calcitriol according to laboratory indicators of mineral metabolism was compared with K/DOQI recommendations. RESULTS: Sevelamer alone (i.e., not combined with other PB) was prescribed for 45.4 percent of patients, calcium carbonate (CaCO3) alone for 26.5 percent, sevelamer combined with CaCO3 for 2.1 percent and calcium acetate for 5.2 percent. Prescription of PB was noted in 53 percent of the patients with phosphorus <3.5 mg/dL and 40 percent with phosphorus <3.0 mg/dL. In disagreement with K/DOQI, prescription of calcitriol was found in 19 percent of patients with PTH<150 pg/mL and prescription was absent for approximately 35.4 percent with PTH>300 pg/dL combined with phosphorus equal or less than 5.5 mg/dL, calcium equal or less than 9.5 mg/dL and calcium x phosphorus product (CaxP)<55 mg2/dL2. For this latter group 38 percent had a prescription of sevelamer without other phosphate binders. CONCLUSION: Results show a large percentage of prescriptions of sevelamer among patients on maintenance hemodialysis in a Brazilian city, despite the high cost of the medication and absence of contraindications for PB with calcium salts. Results in patients with PTH<150 pg/mL and with PTH>300 pg/mL combined with certain concentrations of calcium, phosphate and CaxP also indicate the need to evaluate practices for use of phosphate binders and calcitriol.

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