Current use of equations for estimating glomerular filtration rate in Spanish laboratories.

INTRODUCTION: In 2006 the Spanish Society of Clinical Biochemistry and Molecular Pathology (SEQC) and the Spanish Society of Nephrology (S.E.N.) developed a consensus document in order to facilitate the diagnosis and monitoring of chronic kidney disease with the incorporation of equations for estimating glomerular filtration rate (eGFR) into laboratory reports. The current national prevalence of eGFR reporting and the degree of adherence to these recommendations among clinical laboratories is unknown. METHODS: We administered a national survey in 2010-11 to Spanish clinical laboratories. The survey was through e-mail or telephone to laboratories that participated in the SEQC’s Programme for External Quality Assurance, included in the National Hospitals Catalogue 2010, including both primary care and private laboratories. RESULTS: A total of 281 laboratories answered to the survey. Of these, 88.2% reported on the eGFR, with 61.9% reporting on the MDRD equation and 31.6% using the MDRD-IDMS equation. A total of 42.5% of laboratories always reported serum creatinine values, and other variables only when specifically requested. Regarding the way results were presented, 46.2% of laboratories reported the exact numerical value only when the filtration rate was below 60mL/min/1.73m2, while 50.6% reported all values regardless. In 56.3% of the cases reporting eGFR, an interpretive commentary of it was enclosed. CONCLUSIONS: Although a high percentage of Spanish laboratories have added eGFR in their reports, this metric is not universally used. Moreover, some aspects, such as the equation used and the correct expression of eGFR results, should be improved.

Masa ventricular izquierda, función diastólica y marcadores de metabolismo del colágeno en la hipertensión arterial refractaria / Left ventricular mass, diastolic function and collagen metabolism biomarkers in essential hypertension

Fundamento y objetivo: Evaluar la asociación entre biomarcadores del metabolismo del colágeno, índice de masa ventricular izquierda (IMVI) y función diastólica en pacientes con hipertensión arterial (HTA) refractaria. Pacientes y método:Se estudiaron 52 pacientes diagnosticados de HTA refractaria y se compararon con 24 individuos sanos. Se midió en suero el propéptido C-terminal de la molécula de procolágeno tipo I (PICP) y el factor de crecimiento transformante beta 1 (TGFβ1) por métodos de enzimoinmunoanálisis, y el telopéptido C-terminal del colágeno tipo I (ICTP) por inmunoensayo electroquimioluminiscente. A los pacientes se les practicó una ecocardiografía donde se calculó el IMVI por la fórmula de Devereux y se valoró la función diastólica a partir de la relación entre las ondas E y A (E/A) y la velocidad de propagación mitral. También se les practicó un registro de monitorización de la presión arterial (PA) de 24h. Resultados:Los hipertensos mostraron valores (media ±DE) superiores de PICP e inferiores de ICPT que los controles: 83,7 (24,7) frente a 55,0 (8,7), p<0,0001, y 175,0 (136,4) frente a 323,3 (121,3), p<0,0001. En los hipertensos existió una relación significativa entre el PICP y el IMVI (r=0,631, p<0,0001) y disfunción diastólica (r=-0,519, p<0,0001). Los grupos con y sin hipertrofia, y con o sin función diastólica, diferían en los citados péptidos pero no en las cifras de PA. Conclusiones: Nuestros hallazgos sugieren que diferentes marcadores de la síntesis y de la degradación del colágeno pueden relacionarse con la presencia de hipertrofia miocárdica o disfunción diastólica con independencia de las cifras de PA (AU)

To evaluate the association between circulating biomarkers of collagen metabolism in serum, left ventricular mass index (LVMI) and diastolic dysfunction in patients with resistant hypertension.Patients and methods: Fifty-two patients with resistant hypertension and 24 healthy individuals were included. The following biomarkers of collagen metabolism were analyzed by ELISA: carboxy-terminal propeptide of procollagen type I (PICP) and transforming growth factor beta1 (TGFβ1). The biomarker C-terminal telopeptide of collagen type-I (ICTP) was assayed by electrochemiluminescence immunoassay. In the patient's group a record of 24-h blood pressure monitoring was obtained and an echocardiography was performed. Left ventricular mass was measured according to the formula of Devereux and the diastolic function according to the relation of E and A waves and mitral propagation velocity. Results:Hypertensive patients showed higher levels of PICP and lower levels of ICTP than controls: 83.7 (24.7) vs. 55.0 (8.7), P<.0001; and 175.0 (136.4) vs. 323.3 (121.3), P<.0001). Hypertensive patients showed a significant relationship between PICP and LVMI (r=0.631, P<.0001) and between PICP and diastolic dysfunction (r=-0.519, P<.0001). The groups with and without hypertrophy, and with or without diastolic dysfunction, differed in the mentioned peptides but not in BP values. Conclusions:Our findings suggest that the analyzed markers of synthesis and degradation of collagen may be related to myocardial hypertrophy and diastolic dysfunction independent of blood pressure values (AU)

[Left ventricular mass, diastolic function and collagen metabolism biomarkers in essential hypertension]. / Masa ventricular izquierda, función diastólica y marcadores de metabolismo del colágeno en la hipertensión arterial refractaria.

BACKGROUND AND OBJECTIVE: To evaluate the association between circulating biomarkers of collagen metabolism in serum, left ventricular mass index (LVMI) and diastolic dysfunction in patients with resistant hypertension. PATIENTS AND METHODS: Fifty-two patients with resistant hypertension and 24 healthy individuals were included. The following biomarkers of collagen metabolism were analyzed by ELISA: carboxy-terminal propeptide of procollagen type I (PICP) and transforming growth factor beta1 (TGFß1). The biomarker C-terminal telopeptide of collagen type-I (ICTP) was assayed by electrochemiluminescence immunoassay. In the patient's group a record of 24-h blood pressure monitoring was obtained and an echocardiography was performed. Left ventricular mass was measured according to the formula of Devereux and the diastolic function according to the relation of E and A waves and mitral propagation velocity. RESULTS: Hypertensive patients showed higher levels of PICP and lower levels of ICTP than controls: 83.7 (24.7) vs. 55.0 (8.7), P<.0001; and 175.0 (136.4) vs. 323.3 (121.3), P<.0001). Hypertensive patients showed a significant relationship between PICP and LVMI (r=0.631, P<.0001) and between PICP and diastolic dysfunction (r=-0.519, P<.0001). The groups with and without hypertrophy, and with or without diastolic dysfunction, differed in the mentioned peptides but not in BP values. CONCLUSIONS: Our findings suggest that the analyzed markers of synthesis and degradation of collagen may be related to myocardial hypertrophy and diastolic dysfunction independent of blood pressure values.

TGF-beta 1 y su relación con la hipertensión arterial esencial / Transforming growth factor-Beta1 in essential hypertension

Introducción. Se ha sugerido que los niveles plasmáticos elevados del factor de crecimiento transformante beta 1 (TGF-beta 1) juegan un papel clave para el desarrollo de las enfermedades que cursan con fibrosis. Objetivos. Este estudio observacional, transversal, retrospectivo de casos controles busca evaluar si existe asociación entre los niveles plasmáticos de TGF-beta 1 como factor causal en la patogénesis de la hipertensión arterial (HT-A) esencial y la lesión de órganos diana, en pacientes con HT-A esencial refractaria comparado con un grupo de sujetos sanos y comprobar si existe una correlación entre los niveles de TGF-beta 1 y los de PICP (propéptido C-terminal de la molécula de procolágeno tipo I), de degradación MMP-1 (metaloproteinasa de la matriz tipo 1) y degradación del colágeno ICTP (telopéptido C-terminal de la molécula de colágeno tipo I) en el grupo de sujetos hipertensos. Pacientes y métodos. Se estudiaron 52 pacientes diagnosticados de HT-A con edad media de 53 años y se comparó con grupo control de 24 voluntarios sanos con edad media de 45 años. TGF-beta 1 fue medido por método ELISA previa activación de la muestra. Resultados. Las concentraciones de TGF-beta 1 no fueron mayores en el grupo de hipertensos. La media±desviación estándar fue de 40±13 pg/mL, mientras que en el grupo control fue de 50±23 pg/mL. La t de Student no estableció diferencias significativas. Conclusiones. no se han encontrado niveles elevados de TGF-beta 1 en pacientes con hipertensión esencial en contra de lo evidenciado por otros autores. La exclusión en este estudio de pacientes que presentaban insuficiencia renal moderada o severa, asumimos que pudiera ser la causa de no encontrar elevados los niveles plasmáticos de TGF-beta (AU)

Introduction. It has been suggested that elevated serum transforming growth factor beta1 (TGF-beta 1) levels plays a key role to develope of diseases associated with fibrosis. Objective. This observational, transversal, retrospective case control study was designed to evaluate the association between TGF-beta 1 as causal factor for the hypertension arterial pathogenesis and damage on target organ. This study was designed to evaluate the association between circulating biomarkers of collagen metabolism and fibrosis in serum to compare TGF-beta1 levels obtained in a group of essential hypertension patients with a group of normotensive healthy subjects. Patients and methods. 46 essential hypertension patients, mean age: 53 years versus a control group of 20 healthy volunteers, mean age: 45 years. TGFâ1 was quantitated by a commercial ELISA technique, samples were previously activated. Results. TGF-beta 1 concentrations were not higher in essential hypertension patients, mean serum concentration (40±13ng/mL) than in normal group, mean serum concentration (50±23ng/mL). No significant differences were showed between two groups using t- student test. Conclusion. We have not found elevated TGF-beta 1 concentrations in essential hypertension patients in contrast to what has been shown by other authors. Exclusion of patients with mild or severe renal insufficiency should be considered to be a cause for not obtaining elevated TGF-beta 1 concentrations(AU)