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.

[Clinical usefulness of the reticulocyte hemoglobin equivalent in chronic hemodialysis patients]. / Utilidad clínica de la hemoglobina reticulocitaria equivalente en pacientes en hemodialisis crónica.

BACKGROUND: Iron deficiency is the main cause of failure to respond to erythropoietin (EPO) in haemodialysis patients. Several laboratory tests to detect the deficiency, ferritin and transferrin saturation (TSat) are the most commonly used but its limitations in this patient population are necessary to find other parameters to improve the identification of iron-deficient state. OBJECTIVE: To evaluate the ability of Reticulocyte Hemoglobin Equivalent (RET-He) to predict iron deficiency, taking as a reference standard to the increase of hemoglobin in response to iron intake. MATERIALS AND METHODS: 44 patients on chronic hemodialysis and fixed-dose EPO received 400 mg of intravenous iron. Were measured Hb, Ret-He, IRF, and ferritin prior to iron administration. After 20 to 30 days of completion of loading the patients were classified as responders if hemoglobin increased by at least 0.8 g / L and non-responders if this increase did not occur. RESULT: 25 patients were responders, the ROC curves analysis showed the Ret-He with the largest AUC of 0.862 similar to the AUC of 0.833 that showed the IST, but the first is more sensitive (72% CI 95%: 51-88% vs 52% 95% CI 31-72%) and similar specificity (94.7% CI 95%: 74-100% vs 100% 95% CI 82-100%). Ferritin AUC was 0.772 and finally the IRF AUC was 0.7. The Ret-He, to a cutoff of 29.5 pg was the best combination of sensitivity and specificity (72 and 94.7 respectively), and the sensitivity of the combination Ret-He/IST rose to 80% specificity 94.7%. CONCLUSIONS: According to these results it could consider to Ret-He and the Ret-He/IST combination of clinical utility for the identification of the iron deficit in patients in chronic haemodialysis.

Thrombophilic mutations: no association with thrombotic events in renal transplant recipients.

Factor V Leiden and mutation of prothrombin gene G20210A have been associated with poor results in the early post-kidney transplantation period. Its long-term importance in stable patients has yet to be evaluated. We studied the prevalence of these inherited mutations and their relationship to thrombotic events in 82 Argentine renal transplant recipients with adequate long-term kidney function. In aggregate, 7.2% of patients were carriers of these mutations; however, their presence did not show any association with thrombotic events or renal function alterations. The routine evaluation for these mutations does not seem to be cost-effective in renal transplant patients.

Renal transplantation in diabetic patients.

OBJECTIVE: Diabetes is one of the main causes of end-stage renal disease (ESRD) and admission to hemodialysis, and the demand for kidney transplantation in this population has increased. Our aim was to evaluate the clinical aspects and survival of diabetic patients with kidney transplants by comparing them with the nondiabetic population. MATERIALS AND METHODS: Patients transplanted during the period from 1994 to 2003 were evaluated for this study. The transplant and demographic characteristics were analyzed by the chi-square test and Student t test according to the type of variable. Kaplan-Meier curves and the log-rank test were used to evaluate the graft and patient survival. RESULTS: From a total of 523 consecutive renal transplants, 35 (6.6%) were diabetics who were older than nondiabetics (47 +/- 11 years vs 37 +/- 16, P < .002). Patients received immunosuppression with cyclosporine (84.3%), tacrolimus (11.2%), azathioprine (46.6%), mycophenolate mofetil (43.5%), and steroids (all patients). The diabetic patients had a higher percentage of living donors (33.5% vs 17.2%; P = .04). Graft survival rates at 1, 3, and 5 years were 82.7%, 70.9%, and 63.0% in the diabetic patients and 87.6%, 79.0%, and 72.5% (P = .6) in the nondiabetic patients. Patient survival at 5 years was 90.5% in diabetic patients vs 89.0% in nondiabetic patients (P = .9). CONCLUSIONS: No differences were found in our series in transplant complications or survival in the diabetic patients compared with the nondiabetic patients. Kidney transplants, even with living donors, must be offered to well-selected diabetic patients without reservations.

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

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.(AU)

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 ¹ 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(AU)

[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.

Time course and functional correlates of post-transplant aluminium elimination.

Urinary excretion of aluminium after a successful transplant can reverse pre-transplant aluminium intoxication. We have evaluated the time course of urinary aluminium excretion and its correlation with several parameters of renal function and mineral metabolism in 49 patients (33 men and 16 women) with a wide range of pre-transplant serum aluminium concentrations, performing sequential determinations at pre-transplant time and at 7, 30, 60, and 90 post-transplant days. Mean serum aluminium at pre-transplant was 54.5+/-46.8 microg/l decreasing progressively to 28.7+/-24.4 microg/l at 90 days (P<0.0002), paralleling the decrease in serum creatinine. Urinary aluminium decreased from 63.0+/-77.9 to 52.4+/-55.9 microg/l at 90 days (P<0.0001). The maximum urinary aluminium/creatinine was 1.8+/-2.7 at 7 days and was associated with the greatest fractional excretion of sodium (4.7+/-5.1%), and the lowest tubular reabsorption of phosphate (55.7+/-25.1%). The fractional excretion of aluminium was also greatest at day 7 (1.1+/-0.9%) when serum creatinine was still elevated (3.6+/-2.3 mg/dl). At each period of time after transplantation fractional excretion of aluminium was similar in all patients despite disparate serum aluminium concentrations. Fractional excretion of aluminium was highest in those patients who developed post-Tx acute tubular necrosis (0.7+/-0.5 vs 1.5+/-1.0%, P=0.008). We found a direct positive correlation (r=0.43; P<0.002) between urinary aluminium and urinary phosphate. Basal levels and sequential changes in serum PTH, calcium, and phosphate did not correlated with fractional excretion of aluminium. These findings suggest: (i) urinary aluminium remains elevated during prolonged periods after transplant and is probably a marker of pre-transplant tissue aluminium accumulation; (ii) post-transplant fractional excretion of aluminium seems to correlated positively with other evidences of renal tubular dysfunction. Early post-transplant tubular malfunction could significantly enhance urinary aluminium elimination.

Aluminium removal with the double chamber technique: paired filtration-dialysis (PFD).

Several dialysis techniques have been used to improve aluminium removal. So far there are no data available using paired filtration-dialysis (PFD). In this study, we evaluated the aluminium removed by PFD in two phases. Bovine plasma with known concentrations of aluminium and desferrioxamine was used in both experiments. In phase I, the aluminium removal was investigated using the PFD system (single pass) in its usual configuration, modifying the order of the convective and diffusive processes, dialysis with high permeability membranes and dialysis with low permeability membranes. During the second phase, the experiment lasted longer using recirculation, and the PFD was compared with conventional dialysis using high permeability membranes. Changes in the PFD configuration did not alter the aluminium removal; the efficiency of PFD for aluminium removal was very close to that of dialysis with high permeability membranes and much greater than with low permeability membranes. The aluminium is removed mainly in the first part of the dialysis. Aluminium mobilization using the double chamber technique (PFD) was efficient and might be of value for those patients with aluminium overload who needs high depurative techniques and are unable to tolerate high-flux techniques.

Influence of aluminium overload on the course of post-transplant parathyroid function.

Aluminium intoxication exerts profound effects on secondary hyperparathyroidism in chronic renal failure and could influence the evolution of post-transplant parathyroid function. We have evaluated 44 patients after successful renal transplantation, sequentially from day 0 up to day 90 from the beginning of graft function, determining serum and urinary aluminium, PTH (intact molecule) and several other parameters of mineral metabolism. Patients were grouped according to their basal serum aluminium: Group LA (n = 25) had serum aluminium less than 40 micrograms/l (mean 21 +/- 10 micrograms/l), and Group HA (n = 19) had serum aluminium greater than 40 micrograms/l (mean 100 +/- 43 micrograms/l). This latter group also had greater urinary aluminium excretion during the study period. Evolution of renal function was similar in both groups. Group LA had increased pre-transplant iPTH (353 +/- 416 pg/ml vs 175 +/- 94, P = 0.05). Seven days after regaining renal function both groups showed a marked decrease in iPTH and then a continued decline up to day 90 with mean serum values of the hormone showing no further differences between groups. The incidence of hypercalcaemia was similar in both groups but no patients in Group HA developed hypercalcaemia at post-transplant day 7 while 12% in Group LA did so. Urinary phosphate excretion and the incidence of post-transplant hypophosphataemia were similar in both groups. These findings suggest: (a) patients with more aluminium intoxication have lower values of pre-transplant iPTH and they correct parathyroid function in a different way than non-intoxicated patients in early post-transplant days; (b) they have lower and later incidence of hypercalcaemia.

[Actuarial survival analysis of patients in dialysis]. / Analísis de supervivencia actuarial de pacientes en dialísis.

The survival rate of our end stage renal disease (ESRD) population was calculated by means of actuarial survival curves. A total of 167 patients undergoing hemodialysis or CAPD during the 1977-1991 period were studied. They had been treated and closely followed for at least three months. Mean age for starting dialysis was 40.6 +/- 17 years; 107 (64%) were males and 60 (36%) females. Glomerulonephritis (25%), diabetes (14%) and nephroangiosclerosis (12%) were the primary causes of ESRD. Survival rates were analysed by actuarial curves as designed by Kaplan and Meier. Statistical significance between curves was calculated with the Log Rank test. The level of significance considered was below 0.05. Multivariate analysis of survival was performed using the Cox proportional hazards regression model. Survival rates were in all cases expressed for the 1 degree, 5 degree and 10 degree year. They were for the whole group of 89%, 63%, and 38% respectively. When analysed according to their age: those under 30 years; between 30 and 50 and over 50 years old (at time to start dialysis); survival rates were of 97%, 86%, and 81% for the first group; 89%, 66% and 29% for the second group, and 85%, 44%, and 10% for the third group. Significant differences were found between the first and second group (p < 0.025); the first and the third group (p < 0.001) and second and third group (p < 0.001) (Fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)

Analísis de supervivencia actuarial de pacientes en dialísis. / [Actuarial survival analysis of patients in dialysis]

The survival rate of our end stage renal disease (ESRD) population was calculated by means of actuarial survival curves. A total of 167 patients undergoing hemodialysis or CAPD during the 1977-1991 period were studied. They had been treated and closely followed for at least three months. Mean age for starting dialysis was 40.6 +/- 17 years; 107 (64

) were males and 60 (36

) females. Glomerulonephritis (25

), diabetes (14

) and nephroangiosclerosis (12

) were the primary causes of ESRD. Survival rates were analysed by actuarial curves as designed by Kaplan and Meier. Statistical significance between curves was calculated with the Log Rank test. The level of significance considered was below 0.05. Multivariate analysis of survival was performed using the Cox proportional hazards regression model. Survival rates were in all cases expressed for the 1 degree, 5 degree and 10 degree year. They were for the whole group of 89

, 63

, and 38

respectively. When analysed according to their age: those under 30 years; between 30 and 50 and over 50 years old (at time to start dialysis); survival rates were of 97

, 86

, and 81

for the first group; 89

, 66

and 29

for the second group, and 85

, 44

, and 10

for the third group. Significant differences were found between the first and second group (p < 0.025); the first and the third group (p < 0.001) and second and third group (p < 0.001) (Fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of aluminium intoxication: a new scheme for desferrioxamine administration.

In order to control aluminium toxicity in dialysis patients it is preferable to prevent or limit exposure to it. However, it is sometimes necessary to remove the aluminium by the use of appropriate techniques. The collateral effects of desferrioxamine have led us to test new forms of administering desferrioxamine and attempt to reduce the dose. The aim of this study was to compare the removal of aluminium by administration of 15 mg/kg of desferrioxamine under two different schemes, that is, 44 h before the dialysis (classic scheme) and 1 h before dialysis (new scheme). The study was carried out in 10 patients over a period of 4 weeks. Aluminium removal was quantified in the dialysate throughout the dialysis. Measurement was also performed of the serum aluminium changes that occurred during the study. The total removal of aluminium was determined over three consecutive dialysis sessions following the administration of desferrioxamine. A similar amount of aluminium was found under both schemes. However, in the case of those patients given desferrioxamine 1 h prior to dialysis, removal of aluminium induced significantly lower serum aluminium peaks: (P < 0.02). These results suggest that the administration of desferrioxamine 1 h before dialysis is a valid alternative to the classic scheme (44 h before). The removal of aluminium at lower increments in the serum aluminium entails less risk for patients.