RESUMEN
Bone and mineral metabolism abnormalities are frequent in kidney transplant recipients and have been associated with cardiovascular morbidity. The primary aim of this study was to analyse the association between routine clinically available biochemical evaluation, non-routine histomorphometric bone evaluation, and vascular disease in kidney transplanted patients. A cross-sectional analysis was performed on 69 patients, 1-year after kidney transplantation. Laboratory analysis, radiography of hands and pelvis, bone biopsy, bone densitometry, and coronary CT were performed. One-year post-transplantation, nearly one-third of the patients presented with hypercalcemia, 16% had hypophosphatemia, 39.3% had iPTH levels > 150 pg/mL, 20.3% had BALP levels > 40 U/L, and 26.1% had hypovitaminosis D. Evaluation of extraosseous calcifications revealed low Adragão and Agatston scores. We divided patients into three clusters, according to laboratory results routinely used in clinical practice: hypercalcemia and hyperparathyroidism (Cluster1); hypercalcemia and high BALP levels (Cluster2); hypophosphatemia and vitamin D deficiency (Cluster 3). Patients in clusters 1 and 2 had higher cortical porosity (p = 0.001) and osteoid measurements, although there was no difference in the presence of abnormal mineralization, or low volume. Patients in cluster 2 had a higher BFR/BS (half of the patients in cluster 2 had high bone turnover), and most patients in cluster 1 had low or normal bone turnover. Cluster 3 has no differences in volume, or turnover, but 60% of the patients presented with pre-osteomalacia. All three clusters were associated with high vascular calcifications scores. Vascular calcifications scores were not related to higher bone mineral density. Instead, an association was found between a higher Adragão score and the presence of osteoporosis at the femoral neck (p = 0.008). In conclusion, inferring bone TMV by daily clinical biochemical analysis can be misleading, and bone biopsy is important for assessing both bone turnover and mineralization after kidney transplantation, although hypophosphatemia combined with vitamin D deficiency is associated with abnormal mineralization. The presence of hypercalcemia with high levels of PTH or high levels of BALP, or hypophosphatemia and vitamin D deficiency should remind us to screen vascular calcification status of patients.Clinical Research: ClinicalTrials.gov ID NCT02751099.
Asunto(s)
Hipercalcemia , Hipofosfatemia , Trasplante de Riñón , Calcificación Vascular , Deficiencia de Vitamina D , Humanos , Estudios Transversales , Remodelación Ósea , Deficiencia de Vitamina D/complicaciones , Biopsia , Calcificación Vascular/complicaciones , Densidad Ósea , Hormona ParatiroideaRESUMEN
Abstract Introduction: Type 1 diabetes mellitus is associated with an increased risk of coronary artery disease, which is frequently asymptomatic. This risk increases significantly in those with nephropathy. In selected patients, simultaneous pancreas-kidney transplantation is the renal and pancreatic replacement therapy of choice, as it increases longevity and stabilizes diabetic complications. Despite essential, universal screening protocols are still controversial for coronary artery disease in this population. Methods: We retrospectively analysed 99 simultaneous pancreas-kidney recipients from our centre from 2011 to 2018 and selected 77 patients who underwent coronary angiography during the pre-transplant evaluation. Our aim was to identify potential risk factors associated with significant lesions on coronary angiography. Results: Almost half of our cohort of 77 candidates submitted to coronary angiography had coronary artery disease. Of these, nearly 30% underwent revascularization, although only one of them reported symptoms of myocardial ischemia. In a univariate analysis, the presence of smoking habits was the only risk factor for coronary artery disease. We also found that 20 or more years of type 1 diabetes mellitus was significantly associated with the presence of coronaropathy. Discussion: Selection of diabetic candidates with acceptable cardiac risk before simultaneous pancreas-kidney transplantation is imperative. Given the impact of a correct diagnosis and a low procedural risk, we defend the routine use of coronary angiography as the initial screening method for coronary artery disease in this population. Particularly care must be taken in evaluating asymptomatic patients with long-term type 1 diabetes mellitus and smokers.
Resumo Introdução: O diabetes mellitus tipo 1 está associado ao risco aumentado de doença arterial coronariana, que é frequentemente assintomática. Este risco aumenta significativamente em pessoas com nefropatia. Em pacientes selecionados, o transplante de pâncreas- rim simultâneo é a terapia substitutiva, renal e pancreática, de escolha, pois aumenta a longevidade e estabiliza complicações diabéticas. Apesar de essenciais, protocolos de triagem universais ainda são controversos para doença arterial coronariana nesta população. Métodos: Analisamos retrospectivamente 99 receptores de pâncreas-rim simultâneo de nosso centro, de 2011 a 2018, e selecionamos 77 pacientes que realizaram angiografia coronária durante avaliação pré-transplante. Nosso objetivo foi identificar fatores de risco potenciais associados a lesões significativas na angiografia coronária. Resultados: Quase metade de nossa coorte de 77 candidatos submetidos à angiografia coronária apresentou doença arterial coronariana. Destes, quase 30% foram submetidos à revascularização, embora apenas um tenha relatado sintomas de isquemia miocárdica. Em uma análise univariada, a presença do hábito de fumar foi o único fator de risco para doença arterial coronariana. Também descobrimos que 20 ou mais anos de diabetes mellitus tipo 1 estavam significativamente associados à presença de coronariopatia. Discussão: A seleção de candidatos diabéticos com risco cardíaco aceitável antes do transplante de pâncreas-rim simultâneo é imperativa. Dado o impacto de um diagnóstico correto e baixo risco de procedimento, defendemos o uso rotineiro da angiografia coronária como método de triagem inicial para doença arterial coronariana nesta população. Deve-se ter um cuidado especial na avaliação de pacientes assintomáticos com diabetes mellitus tipo 1 de longa duração e fumantes.