Analysis of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios as inflammatory biomarkers in chronic kidney disease: impact of parathyroidectomy / Análise das relações neutrófilo/linfócito e plaqueta/linfócito como marcadores inflamatórios na doença renal crônica: impacto da paratireoidectomia

Abstract Introduction: Secondary hyperparathyroidism (SHPT) is one of the causes for inflammation in CKD. We assessed the impact of parathyroidectomy (PTX) on neutrophil-to-lymphocyte (N/L) and platelet-to-lymphocyte (P/L) ratios in SHPT patients. Methods: A total of 118 patients [hemodialysis (HD, n = 81), and transplant recipients (TX, n = 37)] undergoing PTX between 2015 and 2021 were analyzed. Results: There was a significant reduction in calcium and PTH levels in both groups, in addition to an increase in vitamin D. In the HD group, PTX did not alter N/L and P/L ratios. In the TX group, there was a reduction in N/L and P/L ratios followed by a significant increase in total lymphocyte count. Conclusion: N/L and P/L ratios are not reliable biomarkers of inflammation in SHPT patients undergoing PTX. Uremia, which induces a state of chronic inflammation in dialysis patients, and the use of immunosuppression in kidney transplant recipients are some of the confounding factors that prevent the use of this tool in clinical practice.

Resumo Introdução: O hiperparatireoidismo secundário (HPTS) é uma das causas de inflamação na DRC. Avaliamos o impacto da paratireoidectomia (PTX) nas relações neutrófilo/linfócito (N/L) e plaqueta/linfócito (P/L) em pacientes com HPTS. Métodos: Foram analisados 118 pacientes [hemodiálise (HD, n = 81) e transplantados (TX, n = 37)] submetidos à PTX entre 2015 e 2021. Resultados: Houve redução significativa de cálcio e PTH nos dois grupos, além de elevação de vitamina D. No grupo HD, a PTX não mudou as relações N/L e P/L. Já no grupo TX, houve redução nas relações N/L e P/L acompanhadas de elevação significativa do número de linfócitos totais. Conclusão: As relações N/L e P/L não são marcadores fidedignos de inflamação em pacientes com HPTS submetidos à PTX. A uremia, que induz um estado de inflamação crônica em pacientes dialíticos, e o uso de imunossupressão em pacientes transplantados renais são alguns dos fatores de confusão que impedem o uso dessa ferramenta na prática clínica.

Analysis of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios as inflammatory biomarkers in chronic kidney disease: impact of parathyroidectomy.

INTRODUCTION: Secondary hyperparathyroidism (SHPT) is one of the causes for inflammation in CKD. We assessed the impact of parathyroidectomy (PTX) on neutrophil-to-lymphocyte (N/L) and platelet-to-lymphocyte (P/L) ratios in SHPT patients. METHODS: A total of 118 patients [hemodialysis (HD, n = 81), and transplant recipients (TX, n = 37)] undergoing PTX between 2015 and 2021 were analyzed. RESULTS: There was a significant reduction in calcium and PTH levels in both groups, in addition to an increase in vitamin D. In the HD group, PTX did not alter N/L and P/L ratios. In the TX group, there was a reduction in N/L and P/L ratios followed by a significant increase in total lymphocyte count. CONCLUSION: N/L and P/L ratios are not reliable biomarkers of inflammation in SHPT patients undergoing PTX. Uremia, which induces a state of chronic inflammation in dialysis patients, and the use of immunosuppression in kidney transplant recipients are some of the confounding factors that prevent the use of this tool in clinical practice.

The Protein-Independent Role of Phosphate in the Progression of Chronic Kidney Disease.

Several factors contribute to renal-function decline in CKD patients, and the role of phosphate content in the diet is still a matter of debate. This study aims to analyze the mechanism by which phosphate, independent of protein, is associated with the progression of CKD. Adult Munich-Wistar rats were submitted to 5/6 nephrectomy (Nx), fed with a low-protein diet, and divided into two groups. Only phosphate content (low phosphate, LoP, 0.2%; high phosphate, HiP, 0.95%) differentiated diets. After sixty days, biochemical parameters and kidney histology were analyzed. The HiP group presented worse renal function, with higher levels of PTH, FGF-23, and fractional excretion of phosphate. In the histological analysis of the kidney tissue, they also showed a higher percentage of interstitial fibrosis, expression of α-actin, PCNA, and renal infiltration by macrophages. The LoP group presented higher expression of beclin-1 in renal tubule cells, a marker of autophagic flux, when compared to the HiP group. Our findings highlight the action of phosphate in the induction of kidney interstitial inflammation and fibrosis, contributing to the progression of renal disease. A possible effect of phosphate on the dysregulation of the renal cell autophagy mechanism needs further investigation with clinical studies.

The disparity of measuring bone mineral content using bioimpedance and dual-energy absorptiometry in the context of hyperparathyroidism.

INTRODUCTION: Body composition is critical for the evaluation of patients with Chronic Kidney Disease (CKD) and can be obtained from either multifrequency bioelectrical impedance analysis (BIA) or dual-energy absorptiometry (DXA). Although the discrepancy between the results obtained from both methods has already been described, reasons are unknown, and might be related to secondary hyperparathyroidism, which is associated with bone loss. METHODS: We have evaluated 49 patients (25 males and 24 females): 20 with CKD not on dialysis and 29 on maintenance hemodialysis [18 with severe hyperparathyroidism (HD-SHPT) and 11 submitted to parathyroidectomy (HD-PTX)]. All patients underwent DXA and BIA. RESULTS: The median age and body mass index (BMI) were 49 years and 25.6 kg/m2, respectively. Patients exhibited low bone mineral content (BMC) measured by DXA, particularly those from the HD-SHPT group. The largest BMC measurement disagreement between DXA and BIA was found in the HD-SHPT group (p=0.004). Factors independently associated with this discrepancy in BMC measurement were serum phosphate (p=0.003) and patient group (p=0.027), even after adjustments for age, BMI, and gender (adjusted r2=0.186). PTX attenuated this difference. DISCUSSION: BIA should be interpreted with caution in patients with SHPT due to a loss of accuracy, which can compromise the interpretation of body composition.

Corneal and Conjunctival Calcification in a Dialysis Patient Reversed by Parathyroidectomy.

Mineral and bone metabolism disorders are relatively common among patients with end-stage renal disease on maintenance hemodialysis. Corneal and conjunctival calcification is the main extravascular site for calcification. Recently, this form of calcification has been linked to vascular calcification. Secondary hyperparathyroidism can lead to high levels of calcium and phosphorus and increase the risk of calcification. Here, we report a case of a 38-year-old female with severe hyperparathyroidism who underwent eye examination before and after parathyroidectomy. Anterior segment optical coherence tomography showed an improvement in the number and size of ocular calcifications 6 months after surgery. This case calls attention to the importance of eye examination in patients on dialysis and brings the possibility of recovery of calcification in a short-term follow-up.