Predicting Future Renal Function Decline in Patients with Autosomal Dominant Polycystic Kidney Disease Using Mayo Clinic Classification.

INTRODUCTION: Mayo clinic classification (MCC) has been proposed in patients with autosomal dominant polycystic kidney disease (ADPKD) to identify who may experience a rapid decline of renal function. Our aim was to validate this predictive model in a population from southern Spain. METHODS: ADPKD patients with measurements of height-adjusted total kidney volume (HtTKV) and baseline estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m2 were selected. Last eGFR was estimated with Mayo Clinic (MC) equation and bias and accuracy were studied. We also analyzed predictive capacity of MCC classes using survival analysis and Cox regression models. RESULTS: We included 134 patients with a mean follow-up of 82 months. While baseline eGFR was not different between classes, last eGFR decreased significantly with them. eGFR variation rate was different according to the MCC class with a more rapid decline in 1C, 1D, and 1E classes. Final eGFR predicted was not significantly different from the real one, with an absolute bias of 0.6 ± 17.0 mL/min/1.73 m2. P10 accuracy was low ranging from 37.5 to 59.5% in classes 1C, 1D, and 1E. Using MC equation, the rate of eGFR decline was underestimated in 1C, 1D, and 1E classes. Cox regression analysis showed that MCC class is a predictor of renal survival after adjusting with baseline eGFR, age, sex, and HtTKV, with 1D and 1E classes having the worst prognosis. CONCLUSION: MCC classification is able to identify patients who will undergo a more rapid decline of renal function in a Spanish population. Prediction of future eGFR with MC equation is acceptable as a group, although it shows a loss of accuracy considering individual values. The rate of eGFR decline calculated using MC equation can underestimate the real rate presented by patients of 1C, 1D, and 1E classes.

Comparison of MDRD and the old CKD-EPI equations with the new CKD-EPI equations in kidney transplant patients when glomerular filtration rate is measured with 51Cr-EDTA. / Comparación de las ecuaciones MDRD y de las antiguas ecuaciones CKD-EPI frente a las nuevas ecuaciones CKD-EPI en pacientes con trasplante renal cuando se emplea 51Cr-EDTA para medir el filtrado glomerular.

BACKGROUND: When estimating the glomerular filtration rate (GFR) in kidney transplant patients, significant differences have been found between MDRD and the 2009 CKD-EPI equations, and reference techniques. OBJECTIVE: To analyse and compare the performance of MDRD and the 2009 and 2012 CKD-EPI equations against 51Cr-EDTA plasma clearance in measuring GFR in 270 kidney transplant patients after one year. RESULTS: The mean measured GFR was 43.0±11.4 (18.2-79.4)ml/min/1.73m2, with creatinine levels of 1.42±0.46 (0.60-4.33)mg/dl and cystatin C levels of 1.45±0.53 (0.42-3.48)mg/l. This correlated moderately with creatinine (r=-0.61, P<.001) and cystatin C (r=-0.52, P<.001). Using linear regression techniques, it was found that creatinine, cystatin C, gender and age only explained 52% of GFR total variance. All equations overestimated GFR, with a mean bias of +11.1ml/min/1.73m2 for MDRD, +16.4ml/min/1.73m2 for 2009-CKD-EPI, +15ml/min/1.73m2 for CKD-EPI with cystatin C, and +14.1ml/min/1.73m2 for 2012-CKD-EPI with creatinine and cystatin C. eGFR by MDRD and the 2009 CKD-EPI equation correlated better with 51Cr-EDTA than CKD-EPI with creatinine and/or cystatin C. The overestimations were negatively correlated with creatinine and cystatin C levels, most significantly for CKD-EPI with creatinine and/or cystatin C when GFR was greater than 60ml/min/1.73m2. CONCLUSIONS: The 2012 CKD-EPI equations with creatinine and/or cystatin C significantly overestimate GFR in stage 1 and 2 chronic kidney disease. The MDRD equations is therefore recommended in these cases. The reference method used to measure GFR seems to heavily influence the bias of the equations.

Overview of autosomal dominant polycystic kidney disease in the south of Spain. / Panorámica de la poliquistosis renal autosómica dominante en una región del sur de España.

INTRODUCTION: Although autosomal dominant polycystic kidney disease is the most common hereditary kidney disease, available data tend to be limited to after initiation of renal replacement therapy. OBJECTIVE: To ascertain an overview of autosomal dominant polycystic kidney disease within the health area of Granada in southern Spain. MATERIAL AND METHODS: From January 2007 to December 2016, we collected clinical, family and demographic information about all patients with autosomal dominant polycystic kidney disease, irrespective of whether or not they were treated with RRT, in the Granada health area. The computer software SPSS 15.0 and GenoPro were used. RESULTS: 50.6% of the 1,107 diagnosed patients were men. 99.1% were Caucasian and 4-6 generations/family were studied. The geographical distribution was heterogeneous. There was no family history in 2.43%. The mean age of diagnosis was 34.0±17.80 years and the diagnosis was made after having offspring in 57.7% of cases. The main reason for diagnosis was family history (46.4%). The mean age of initiation of renal replacement therapy was 54.2±11.05 years. 96.3% of the deceased had some degree of renal failure at the time of death. The mean age of death was 60.9±14.10 years, the main cause of death being unknown in 33.5% of cases, followed by cardiovascular (27.8%). CONCLUSIONS: Cases and families were concentrated in certain geographical areas and a significant number of individuals were undiagnosed prior to cardiovascular death or diagnosed late after reproduction. Given that there is currently no curative treatment, the primary prevention strategy of preimplantation genetic diagnosis should play a leading role.

[OSTEOPOROSIS AND BODY MASS INDEX IN RENAL TRANSPLANT RECIPIENTS]. / OSTEOPOROSIS E ÍNDICE DE MASA CORPORAL EN EL TRASPLANTADO RENAL.

INTRODUCTION: frequently after kidney transplantation there is an increase in weight with a resulting high percent of obesity in these recipients. This combined with a rapid loss of bone mass, a higher prevalence of osteoporosis and fractures is evident than in normal populations. OBJECTIVES: to explore the relationship between body mass index (BMI) and prevalence of osteoporosis in a population of renal transplant recipients. METHODS: prospective longitudinal study design. The study was conducted on 306 kidney transplant recipients. The relationship between weigh and body mass index with femoral and lumbar osteopenia and osteoporosis prevalence at the moment of transplant and at 12 months post was explored. RESULTS: there was a high prevalence of overweight (35.6%) and obese (14.1%) recipients after renal transplant and 1 year after (42.2% and 24.2% respectively). Significant differences were found(p = 0.049) between the weight at the time of transplant and the presence of osteopenia or osteoporosis at the lumbar level one year after, the highest weights were in recipients with osteoporosis. The mean BMI was higher (p = 0.028) in osteoporotic patients (26.59 kg/m2) than in patients with osteopenia (24.23 kg/m2). CONCLUSION: results seem to be consistent with recent studies in the general population showing excessive weight as a possible factor detrimental to the bone health.

Introducción y objetivos: tras el trasplante renal es frecuente un aumento de peso, así como un elevado porcentaje de obesidad en estos pacientes. Por otro lado, tras el trasplante se produce una pérdida de la masa ósea, siendo la prevalencia de osteoporosis y fracturas óseas mayor que en la población general. Objetivos: explorar la relación entre el índice de masa corporal y la prevalencia de osteopenia y osteoporosis en una población de trasplantados renales. Material y método: estudio longitudinal prospectivo sobre una muestra de 306 trasplantados renales. Se exploraron las relaciones entre el peso y el índice de masa corporal con la prevalencia de osteopenia y osteoporosis a nivel femoral y lumbar en el momento del trasplante y a los 12 meses del mismo. Resultados: se halló una alta prevalencia de sobrepeso (35,6%) y obesidad (14,1%) tras el trasplante renal y al año del mismo (42,2% y 24,2%, respectivamente). Se hallaron diferencias estadísticamente significativas (p = 0,049) entre el peso en el momento del trasplante y la presencia de osteopenia u osteoporosis al año del mismo a nivel lumbar, siendo el peso medio más elevado entre los pacientes con osteoporosis. La media del IMC fue más elevada (p = 0,028) en los pacientes osteoporóticos (26,59 kg/m2) que en los pacientes con osteopenia (24,23 kg/m2). Conclusiones: nuestros resultados parecen estar en concordancia con recientes estudios realizados en la población general, que muestran el sobrepeso como un posible factor perjudicial para el hueso.

Effect of paricalcitol on mineral bone metabolism in kidney transplant recipients with secondary hyperparathyroidism.

INTRODUCTION: Secondary hyperparathyroidism is highly prevalent in kidney transplant recipients, and commonly results in hypercalcaemia; an association to osteopenia and bone fractures has also been observed. Paricalcitol has proved effective to control secondary hyperparathyroidism in chronic kidney disease in both dialysed and non-dialysed patients, with a low hypercalcaemia incidence. Currently available experience on paricalcitol use in kidney transplant recipients is scarce. Our main aim was to show the effect of paricalcitol on mineral bone metabolism in kidney transplant recipients with secondary hyperparathyroidism. MATERIAL AND METHODS: A retrospective multicentre study in kidney transplant recipients aged>18 years with a 12-month or longer post-transplantation course, stable renal function, having received paricalcitol for more than 12 months, with available clinical follow-up for a 24-month period. RESULTS: A total of 69 patients with a 120 ± 92-month post-transplantation course were included. Baseline creatinine was 2.2 ± 0.9 mg/dl y GFR-MDRD was 36 ± 20 ml/min/1.73 m(2). Paricalcitol doses were gradually increased during the study: baseline 3.8 ± 1.9 µg/week, 12 months 5.2 ± 2.4 µg/week; 24 months 6.0 ± 2.9 µg/week (P<.001). Serum PTH levels showed a significant fast decline: baseline 288 ± 152 pg/ml; 6 months 226 ± 184 pg/ml; 12 months 207 ± 120; 24 months 193 ± 119 pg/ml (P<.001). Reduction from baseline PTH was ≥30% in 42.4% of patients at 12 months y in 65.2% of patients at 24 months. Alkaline phosphatase showed a significant decrease in first 6 months followed by a plateau: baseline 92 ± 50 IU/l; 6 months 85 ± 36 IU/l, 12 months 81 ± 39 IU/l (P<.001). Overall, no changes were observed in serum calcium and phosphorus, and in urine calcium excretion. PTH decline was larger in patients with higher baseline levels. Patients with lower baseline calcium levels showed significantly increased levels (mean increase was 0.5-0.6 mg/dl) but still within normal range, whereas patients with baseline calcium>10mg/dl showed gradually decreasing levels. Fifteen (21.7%) patients had received prior calcitriol therapy. When shifted to paricalcitol, such patients required paricalcitol doses significantly larger than those not having received calcitriol. Paricalcitol was used concomitantly to cinacalcet in 11 patients with significant PTH reductions being achieved; clinical course was similar to other patients and paricalcitol doses were also similar. CONCLUSIONS: Paricalcitol is an effective therapy for secondary hyperparathyroidism in kidney transplant recipients. Overall, no significant changes were observed in calcium and phosphorus levels or urinary excretion. Patients having previously received calcitriol required higher paricalcitol doses. When used in patients receiving cinacalcet, paricalcitol results in a significant PTH fall, with paricalcitol doses being similar to those used in patients not receiving cinacalcet.

[Cystinosis: diagnosis through the measurement of the leukocyte cystine content by HPLC]. / Cistinosis: diagnóstico mediante la determinación del contenido de cistina intraleucocitaria por cromatografía líquida de alta resolución.

BACKGROUND AND OBJECTIVE: Cystinosis is an autosomal recessive disorder characterized by an accumulation of intralysosomal cystine. Three disease forms exist, infantile, juvenile or late-onset, and ocular nonnephropathic cystinosis, delineated on the basis of severity of symptoms and age of onset. The knowledge of early clinic manifestations and the onset of the appropriate therapy delay the evolution of the disease and improve the general conditions. Therefore, it is necessary to develop a sensible diagnostic method for early detection and treatment of the disease. CLINICAL CASE AND METHODS: The leukocyte cystine content was determined by HPLC in a 42 years old female patient after renal transplantation, and with the clinical characteristic complications of the intermediate cystinosis. Equally, the molecular characterization of the structural defects of the cystinosin (CTNS) gene was made in the patient and in all family members. RESULTS: By measuring of the leukocyte cystine content in the patient and family members, we have determined 5 family members as heterozygous. This result was confirmed by molecular analysis that showed the approximately 65 kb deletion in the 5 family members. The patient was heterozygous for the approximately 65 kb deletion, and the second alteration was not determined. CONCLUSIONS: We presented a useful diagnostic method, based in the determination of cystine content of polymorphonuclear leukocytes, which permits to detect the heterozygous individuals.