Paratiroidectomía en pacientes renales crónicos en Argentina: estudios prequirúrgicos, tipos de cirugía, recurrencia y persistencia / Parathyroidectomy in chronic kidney disease patients in Argentina: pre surgical studies, types of surgery, recurrence and persistence

La paratiroidectomía (PTx) es el tratamiento de elección en pacientes con HPT 2º severo, refractario al tratamiento médico. Se cuenta con muy poca información en Argentina de este procedimiento, por lo cual se realizó este estudio. Material y Métodos: Se incluyeron 255 pacientes con PTx entre el año 2003 al 2007 de un registro voluntario. Se evaluaron los estudios de localización prequirúrgicos, de laboratorio de metabolismo fosfocálcico previo y posterior a la cirugía y el tipo de técnica quirúrgica utilizada. Se analizó la persistencia y recidiva del HPT postcirugía. Resultados: La tasa de PTx fue de 2,7/1000 pacientes año. 83% de los pacientes tuvieron ecografía de cuello y 59% Sesta Mibi con Tc 99. Hubo una correlación positiva (p<0.001) entre el número de glándulas detectadas por ecografía y Sesta Mibi. La paratiroidectomía realizada fue: subtotal en 77%, total con autoimplante en 14% y total sin autoimplante en 9%. Hubo descensos significativos de Ca y P, fosfatasa alcalina y PTH (1744 ± 788 pg/ml a 247 ±450 pg/ml; p<0.0001) postcirugía. A los 2,4 ±2,5 meses de la PTx, el 72% de los pacientes tenía PTH <250 pg/ml, 19,8% tenía persistencia y 8,3% había recidivado. De acuerdo al tipo de cirugía la persistencia y recidiva fueron para PTx subtotal 22% y 8,3%, PTx total con implante 11% y 11% y PTx total sin autoimplante 13% y 4% respectivamente. La realización de Sesta Mibi no influyó en los resultados de la PTx. No se observaron diferencias entre los centros en relación con persistencia y recidiva. Conclusiones: La tasa de PTx fue muy baja, la ecografía fue el método de localización prequirúrgico preferido y la PTX subtotal la técnica quirúrgica más utilizada. La PTx fue exitosa en la mayoría de los pacientes y la persistencia y recidiva no estuvieron relacionadas con la técnica.

Parathyroidectomy (PTx) is the selecte treatment for patients with severe secondary hyperparathyroidism, refractory to medical treatment. There is not enough information about this procedure in Argentina, that is the reason why we performed this study. Material and Methods: 255 patients with PTx were included from the year 2003 to 2007 on a voluntary register. Studies of pre-surgical localization, phosphocalcic metabolism laboratories before and after surgery were evaluated, and the type of surgical technique used. The persistence and recurrence of post-surgical hyperparathyroidism was analyzed. Results: The PTx rate was 2,7/1000 patients year. 83% of the patients had neck echography and 59% Sestamibi scans with Tc 99. There was a positive correlation (p<0,001) between the number of detected glands by echography and Sestamibi. The parathyroidectomy performed was: subtotal in 77%, total with self-implant in 14% and total without self-implant in 9%. There were significant falls of Ca and P, Alkaline Phosphatase and PTH (1744±788 pg/ml to 247±450 pg/ml; p<0.0001) post-surgical. 2.4 ±2,5 months after the PTx, 72% of patients had PTH <250 pg/ml, 19,8% had persistence and 8,3% had recurrence. According to the type of surgery, the persistence and recurrence were for subtotal PTx 22% and 8,3%, total PTx with implant 11% and 11%, and total PTx without selfimplant 13% and 4% respectively. The performance of the Sestamibi scan did not affect the PTx results. No noticeable differences were observed among the centers for persistence and recurrence. Conclusions: The PTx rate was very low, echography was the preferred method of pre-surgical localization, and subtotal PTx was the most used surgical technique. PTx was successful in most of the patients, and persistence and recurrence were not related to the technique.

Expanded criteria donors, histological scoring, and prolonged cold ischemia: impact on renal graft survival.

The use of expanded donors or kidneys with preexistent chronic damage remains controversial, but they offer the opportunity to expand the donor pool. We investigated the impact of these conditions as predictors of graft survival among a cohort of recipients with prolonged cold ischemia times and a high incidence of delayed graft function. We included 70 consecutive cadaveric kidney allografts implanted between 2001 and 2005, which had undergone an early graft biopsy. Delayed graft function was present in 84% of cases with moderate or severe preexistent chronic damage in 63% and 27% of biopsies, respectively, and acute rejection was diagnosed in 14.3% of overall cases. The graft survival was 73.3% at 48 months. Primary nonfunctioning kidneys were more frequent using kidneys from expanded compared with standard donors (20.0% vs 0.0%, P < .002). Multivariate analysis showed that only the donor condition (standard vs expanded) was independently associated with graft survival (hazard ratio: 0.12; 95% confidence interval: 0.01-0.87; P < .03). Our results suggested that the donor characteristics prevail over other variables to predict graft outcomes.

Infección urinaria temprana en trasplante renal. Factores de riesgo y efecto en la sobrevida del injerto / Early urinary tract infection in kidney transplantation. Risk factors and impact on graft survival

The early urinary tract infection (EUTI) in kidney transplant recipients is an infection develop during the first 3 months post transplant surgery. The effect of EUTI on graft survival and risk factors have been scarcely studied. Our objetives were the evaluation of risk factors to EUTI, the assessment of the causal agent and graft survival impact. A retrospective analysis of kidney transplantation, period 1997-2000 in Hospital Privado-Centro Médico de Córdoba was carried out. There were two groups of patients with (EUTI group) and without EUTI (control group). Cox model was used to analyze risk factors and Kaplan-Meier method for graft survival. A total of 226 consecutive patients received kidney transplantation. In 55 patients (24.3%) EUTI was detected. Risk factors for EUTI were: invasive urological maneuvers (RR = 4.34, CI 95% 1.42-13.21), diabetes mellitus (RR = 3.79, CI 95% 1.42-10.14), cytomegalovirus infection (RR = 2.9, CI 95% 1.02-8.24) and previous transplants (RR = 2.83, CI 95% 1.08-7.45). Delayed graft function was associated with lower incidence of EUTI (RR = 0.38, CI 95% 0.15-0.94). The causal agents were: Klebsiella pneumoniae (36%), Pseudomonas aeruginosa (24%) and Escherichia coli (9%). Graft survival at 2 years was similar in EUTI (87.2%) and control group (81.2%, p = 0.32). This series shows that invasive urological maneuvers were the main risk factors for EUTI. Graft survival was similar. High prevalence of non coli bacteria need further evaluation.

La infección urinaria temprana del injerto (IUTI), definida como infección urinaria sintomática en los primeros 3 meses del trasplante, su efecto sobre la sobrevida del injerto y los factores de riesgo han sido poco estudiados. Los objetivos del presente análisis fueron conocer factores de riesgo para IUTI,analizar agentes causantes e impacto en la sobrevida del injerto. En forma retrospectiva se analizaron pacientesque recibieron trasplante renal durante 1997-2000 en el Hospital Privado – Centro Médico de Córdoba. Sedividió en dos grupos de pacientes, según presencia (grupo IUTI) o ausencia (grupo control) de IUTI. Los factores de riesgo se analizaron con el modelo de riesgos proporcionales de Cox y la sobrevida del injerto con elmétodo de Kaplan-Meier. Recibieron trasplante renal 226 pacientes consecutivos. La IUTI se presentó en 55(24.3%). Factores de riesgo asociados con IUTI: antecedentes de maniobras urológicas invasivas (RR=4.34,IC 95% 1.42-13.21), diabetes mellitus (RR=3.79, IC 95% 1.42-10.14), infección por citomegalovirus (RR=2.9,IC 95% 1.02-8.24) y antecedente de trasplante previo (RR=2.83, IC 95% 1.08-7.45). El retardo en la función delinjerto (RR=0.38, IC 95% 0.15-0.94) se asoció con menor incidencia de IUTI. Agentes más frecuentes: Klebsiellapneumoniae (36%), Pseudomonas aeruginosa (24%) y Escherichia coli (9%). La sobrevida del injerto a los 2años en el grupo IUTI (87.2%) no fue diferente del control (81.2%, P = 0.32). En esta serie las maniobras urológicas invasivas fueron el principal factor de riesgo asociado a IUTI. No hubo disminución de la sobrevida del injerto asociada a IUTI. La alta prevalencia de uropatógenos no coli requiere mayor evaluación

[Biochemical and histological spectrum of renal osteodystrophy in Argentina]. / Espectro bioquímico e histológico de la osteodistrofia renal en Argentina.

Between 1994-2001 we have performed 57 bone biopsies for diagnostic purposes in symptomatic CRF patients. We analyzed here 52 samples where the material was optimal for study, and divided them into 2 periods according to when the biopsy was performed: 1994-1996 and 1997-2001, to verify changes in the spectrum of renal osteodystrophy. Mean serum values were: serum calcium 9.9 +/- 1.8 mg/dl, phosphate 5.8 +/- 3.2 mg/dl, alkaline phosphatase 693.9 +/- 968.9 Ul/L, iPTH 562.0 +/- 598.5 pg/ml, serum aluminum 65.7 +/- 79.3 ug/L and bone aluminum 22.8 +/- 22.4 ug/g. Hyperparathyroidism was the most common histological diagnosis as severe in 13 patients (25%), or as mild in 14 (27%). Ten patients had osteomalacia (19%), adynamic bone disease was diagnosed in 5 (9.6%) and mixed renal osteodystrophy in 10 (19.2%). Low bone turnover patients showed higher bone and serum aluminum than high bone turnover patients. We observed a relative increment in high turnover bone disease in the later period (1997-2001) without changes in low turnover bone disease. These data showed a high prevalence of hyperparathyroidism and aluminum-related low turnover bone disease, with no significant changes between the two time-periods analyzed here.

[Importance of the "adequate blood phosphorus" concept as a risk factor for hyperphosphatemia]. / Importancia del concepto "fosfatemia adecuada" como factor de riesgo de hiperfosfatemia.

Hyperphosphatemia is an important risk factor of secondary hyperparathyroidism and extraosseous calcifications in chronic renal failure patients. In this study our hypothesis is that physicians misconception of adequate phosphatemia is a risk factor for hyperphosphatemia. In 1999 GEMOR sent a renal osteodystrophy inquiry to different hemodialysis centers in Argentina. It included 80 dialysis centers in 17 Argentinian provinces. The enquire had 33 questions about renal osteodystrophy. Here we report the section related to phosphorous metabolism. We obtained responses from 80 dialysis centers (4,512 dialysis patients), which represents about 24% of Argentinian dialysis centers. Physicians considered phosphorous levels between 4.5 to 5.5 mg/dl in 83.5% of centers as adequate, and between 5.5 to 6.5 mg/dl in 10.1%. Five out of 77 centers reported that they had no patients with hyperphosphatemia. The percentage of hemodialysis patients that had more than 6 mg/dl in each center was 28.8 +/- 15.9%. Those centers that aimed for phosphatemia between 5.5 and 6.5 mg/dl, had a higher percentage of patients with phosphatemia above 6 mg/dl than those aiming for between 4.5 and 5.5 mg/dl (42.8 +/- 16.7 vs 27.1 +/- 15.2% respectively, p = 0.007), and had higher mean of phosphatemia (6.4 +/- 0.7 vs 5.3 +/- 0.7 mg/dl respectively, p = 0.0001), than the last group. In conclusion, a higher mean phosphate level was obtained in hemodialysis centers where physicians considered higher pre-dialysis target levels. Some centers had no patients with hyperphosphatemia (neglect or good control?).

Different patterns of renal osteodystrophy in Iberoamerica.

The various forms of renal osteodystrophy are predominant hyperparathyroid bone disease, mixed uremic osteodystrophy, low turnover osteomalacia, and adynamic bone disease. The present study analyses a total number of 1,209 bone biopsies from 5 different countries (Brazil, Uruguay, Argentina, Portugal, and Spain). Low turnover osteomalacia and mixed uremic osteodystrophy were more common in Brazil, Uruguay, and Argentina than in Portugal and Spain whereas predominant hyperparathyroid bone disease was seen more often in Portugal and Spain. In all centers, independent of the aluminum staining technique used, the extent of aluminum deposited in bone was greater in patients presenting with low bone turnover, whether from low turnover osteomalacia or adynamic bone disease, than in the predominant hyperparathyroid bone disease. In summary, even though recent reports have indicated that, over the last decade, the incidence of aluminum-induced toxicity was reduced, aluminum still seems to be implicated in a great percentage of symptomatic low bone remodelling lesions in Iberoamerica.