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Healthcare for patients with advanced chronic kidney disease (ACKD) on conservative treatment very often poses healthcare problems that are difficult to solve. At the end of 2011, we began a program based on the care and monitoring of these patients by Primary Care Teams. ACKD patients who opted for conservative treatment were offered the chance to be cared for mainly at home by the Primary Care doctor and nurse, under the coordination of the Palliative Care Unit and the Nephrology Department. During 2012, 2013, and 2014, 76 patients received treatment in this program (mean age: 81 years; mean Charlson age-comorbidity index: 10, and mean glomerular filtration rate: 12.4 mL/min/1.73 m²). The median patient follow-up time (until death or until 31 December 2014) was 165 days. During this period, 51% of patients did not have to visit the hospital's emergency department and 58% did not require hospitalization. Forty-eight of the 76 patients died after a median time of 135 days in the program; 24 (50%) died at home. Our experience indicates that with the support of the Palliative Care Unit and the Nephrology Department, ACKD patients who are not dialysis candidates may be monitored at home by Primary Care Teams.

In the last decade, Acute Kidney Injury (AKI) diagnosis and therapy have not notably improved probably due to delay in the diagnosis, among other issues. Precocity and accuracy should be critical parameters in novel AKI biomarker discovery. microRNAs are key regulators of cell responses to many stimuli and they can be secreted to the extracellular environment. Therefore, they can be detected in body fluids and are emerging as novel disease biomarkers. We aimed to identify and validate serum miRNAs useful for AKI diagnosis and management. Using qRT-PCR arrays in serum samples, we determined miRNAs differentially expressed between AKI patients and healthy controls. Statistical and target prediction analysis allowed us to identify a panel of 10 serum miRNAs. This set was further validated, by qRT-PCR, in two independent cohorts of patients with relevant morbi-mortality related to AKI: Intensive Care Units (ICU) and Cardiac Surgery (CS). Statistical correlations with patient clinical parameter were performed. Our results demonstrated that the 10 selected miRNAs (miR-101-3p, miR-127-3p, miR-210-3p, miR-126-3p, miR-26b-5p, miR-29a-3p, miR-146a-5p, miR-27a-3p, miR-93-3p and miR-10a-5p) were diagnostic biomarkers of AKI in ICU patients, exhibiting areas under the curve close to 1 in ROC analysis. Outstandingly, serum miRNAs estimated before CS predicted AKI development later on, thus becoming biomarkers to predict AKI predisposition. Moreover, after surgery, the expression of the miRNAs was modulated days before serum creatinine increased, demonstrating early diagnostic value. In summary, we have identified a set of serum miRNAs as AKI biomarkers useful in clinical practice, since they demonstrate early detection and high diagnostic value and they recognize patients at risk.

Objectives: Acute kidney injury (AKI) after cardiac surgery is associated with adverse patient outcome. A new definition and staging system for AKI based on creatinine kinetics (CKs) has been proposed recently. Their proponents hypothesize that early absolute increases in serum creatinine (sCr) after kidney injury are superior to percentage increases, especially in patients with chronic kidney disease (CKD). The aims of our study were to measure agreement between CK definition and the current consensus definition [risk, injury, failure, loss and end-stage renal disease (RIFLE) system], and to compare time to diagnosis and prognostic value between both systems., Methods: Retrospective cohort study. Agreement on AKI diagnosis by both classifications, time to diagnosis and prognostic value of both systems were compared in cardiac surgeries performed during a 6-year period (2002-2007) in a single centre., Results: We found substantial agreement between both classifications (0.67). More patients were diagnosed with AKI by the CK definition than by RIFLE criteria both globally (28.2 vs 13.9%) and in every category (16.5 vs 8.4% for CK-1 vs RIFLE-R; 8.4 vs 3.6% for CK-2 vs RIFLE-I and 3.2 vs 2.0% for CK-3 vs RIFLE-F). Time to diagnosis was shorter for the CK definition (1.8 vs 2.5 days). Prognostic value in terms of information about in-hospital death and need for renal replacement was comparable between classifications., Conclusions: In cardiac surgery, the CK definition and classification system showed substantial agreement with the current standard, was more sensitive than RIFLE and detected AKI earlier without loss of prognostic information., (© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

We describe an unusual case of severe hypokalemia with electrocardiographic changes, due to licorice consumption, in a 15-year-old female student with no previous medical history. Prompt replacement of potassium and cessation of licorice ingestion resulted in a favourable outcome. We also discuss the pathophysiology and diagnosis, emphasizing the importance of a detailed anamnesis to rule out an often forgotten cause of hypokalemia as the licorice poisoning.

microRNAs are small, endogenous RNA molecules which are critical for a new step in the regulation of the gene expression. They have become the most critical biological mediators characterized in the last ten years. microRNAs participate in almost every cellular process, therefore their deregulation is associated with the development of a wide range of pathologies, including kidney diseases. Increasing evidence demonstrates that microRNAs are key regulators of the normal kidney function and development, but they are also at the basis of several renal diseases. Recent works have established that these molecules can be secreted to extracellular environments, enabling their detection in peripheral body fluids such as urine and serum. Moreover, circulating miRNAs detected in body fluids turn into suitable biomarkers of kidney diseases, including acute kidney injury. This new generation of renal biomarkers could have a great impact in the clinical practice, significantly contributing to improve patient management. In this review, we discuss over the implication of microRNAs in normal kidney function and homeostasis as well as the role of circulating miRNAs as novel biomarkers of kidney diseases, focusing on their potential usefulness in acute kidney injury management.

Background: Delayed nephrology consultation (NC) seems to be associated with worse prognosis in critically ill acute kidney injury (AKI) patients., Design Setting Participants & Measurements: The aims of this study were to analyze factors related with timing of NC and its relation with AKI patients' outcome in intensive care units of a tertiary hospital. AKI was defined as an increase ≥50% in baseline serum creatinine (SCr). Early NC and delayed NC were defined as NC performed before and two days after AKI diagnosis day. Multivariable logistic regression and propensity scores (PS) were used to adjust for confounding and selection biases. Hospital mortality and dialysis dependence on hospital discharge were the primary outcomes., Results: A total of 366 AKI patients were analyzed and NCs were carried out in 53.6% of the patients. Hospital mortality was 67.8% and dialysis required in 31.4% patients (115/366). Delayed NCs (34%) occurred two days after AKI diagnosis day. This group presented higher mortality (OR: 4.04/CI: 1.60-10.17) and increased dialysis dependence (OR: 3.00/CI: 1.43-6.29) on hospital discharge. Four variables were retained in the PS model for delayed NC: diuresis (1000 ml/24 h--OR: 1.92/CI: 1.27-2.90), SCr (OR: 0.49/CI: 0.32-0.75), surgical AKI (OR: 3.67/CI: 1.65-8.15), and mechanical ventilation (OR: 2.82/CI: 1.06-7.44). After correction by PS, delayed NC was still associated with higher mortality (OR: 3.39/CI: 1.24-9.29) and increased dialysis dependence (OR: 3.25/CI: 1.41-7.51). Delayed NC was associated with increased mortality either in dialyzed patients (OR: 1.54/CI: 1.35-1.78) or non-dialyzed patients (OR: 2.89/CI: 1.00-8.35)., Conclusion: Delayed NC was associated with higher mortality and increased dialysis dependence rates in critically ill AKI patients at hospital discharge. Further studies are necessary to ascertain whether this effect is due to delayed nephrology intervention or residual confounding factors.

Introduction and Objectives: The current definition and classification of acute kidney injury is based on consensus criteria (RIFLE and AKIN systems). Creatinine is the most commonly used of the recommended parameters (creatinine, glomerular filtration rate and diuresis). If the baseline value is not known, it can be calculated based on the simplified MDRD equation, assuming a filtration rate of 75 ml/min/1.73 m2 for the calculation. The aim of this study was to evaluate the diagnostic impact of using estimated baseline creatinine compared to the actual value measured in patients undergoing cardiac surgery., Methods: Analysis of patients undergoing major cardiac surgery, who were prospectively included in a database. The maximum RIFLE stage reached was calculated for each patient using the measured and estimated baseline creatinine levels. The impact on the diagnosis was analysed using intraclass correlation coefficients, concordance analysis and Bland-Altman plots., Results: The incidence of postoperative acute kidney injury in 2103 cases between 2002 and 2007 was 29.1%, according to estimated creatinine (14.3% with the measure). This represents an overestimation of 104%, with an intraclass correlation of 0.12. By excluding patients with known chronic kidney disease (glomerular filtration rate [<60 ml/min/1.73 m2), both the overestimation (2.4%) and the correlation (0.57) improved., Conclusions: The calculation of baseline creatinine using the MDRD equation overestimates the incidence of acute kidney injury after cardiac surgery, and is an inadequate method for detection when the baseline value is unknown.

Acute tubular necrosis (ATN) caused by ischemia/reperfusion (I/R) during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α), using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant.

Background: Severity scores are useful to guarantee similar disease severity among groups in clinical trials and to enable comparison between different studies. The aim of this study was to assess the performance of the third generation models of severity scoring systems [simplified acute physiology score (SAPS) 3, acute physiology and chronic health evaluation (APACHE) IV and mortality probability model (MPM)-III] in acute kidney injury (AKI) patients in the intensive care unit (ICU)., Methods: Three hundred and sixty-six consecutive AKI critically ill patients were prospectively assessed in six ICUs of an academic tertiary care center. Scores were applied on AKI diagnosis day (DD) and on the day of nephrology consultation (NCD). Discrimination was assessed by area under the receiver operating characteristic curve (AUCROC) and calibration by Hosmer-Lemeshow (HL) goodness-of-fit test., Results: Hospital mortality rate was 67.8%. SAPS 3 general and Central and South America (CSA) customized equations presented identical good discrimination (AUCROC curve: 0.80 on NCD) and satisfactory HL tests on both analyzed days (P > 0.100). CSA SAPS 3 equation predicted mortality more accurately [standardized mortality ratio (SMR) on NCD = 1.00 (95% confidence interval (CI) 0.84-1.34)]. APACHE IV and MPM-III scores presented similar discrimination compared to SAPS 3 on both analyzed days (P > 0.05). APACHE IV presented satisfactory HL tests over time (P > 0.100) but underestimated mortality [SMR on DD = 1.92 (95% CI 1.61-2.23); SMR on NCD = 1.46 (95% CI 1.48-1.96)]. MPM-III showed unsatisfactory HL test results (P = 0.027 on DD; P = 0.045 on NCD) and underestimated mortality [SMR on NCD = 2.09 (95% CI 1.48-1.96)]., Conclusions: SAPS 3, especially the geographical customized equation, presented good discrimination and calibration performances, accurately predicting mortality in this group of AKI critically ill patients.

General and specific severity scores for patients with acute kidney injury have significant limitations due in part to the diversity of methods that have been used. Here we prospectively validated five general (APACHE II, SAPS II, SOFA, LODS, and OSF) and three specific (SHARF, Liaño, and Mehta) scoring systems in 366 critically ill patients who developed acute kidney injury in the intensive care unit. Sequential scores in each system were determined on the day that acute kidney injury was diagnosed, on the day when acute kidney injury-specific score criteria were achieved, and on the day of initial nephrology consultation. Acute kidney injury, defined as an increase of 50% or more in the baseline serum creatinine, was mainly due to sepsis, and had an incidence of 19% and an overall 68% mortality. A progressive improvement in score performance was found. On the day of initial nephrology consultation, most scores showed a good performance and two indices (SAPS II and SHARF) achieved an area under the receiver operating characteristic curve above 0.80. Calibration was good on all three defining days, except for OSF when score criteria were achieved, and Mehta at the time of nephrology consultation. Our study shows that early and sequential evaluation is a better approach for prognostic scoring in critically ill patients who develop acute kidney injury.

Background: Data on long-term effects of acute kidney injury (AKI) on renal function (RF) are scarce and factors implicated in the functional outcome are not established. Our aim was to investigate these aspects., Methods: At hospital discharge and annually for 10 years, we retrospectively reviewed RF of 187 patients surviving AKI. Glomerular filtration rates estimated with MDRD equation (eGFR) and KDOQI stages were used to evaluate RF. Only 34.8% of patients had pre-existing renal dysfunction (KDOQI-3). Variables determining long-term RF were collected during AKI and at discharge and analysed with a regression model., Results: At discharge no patient necessitated dialysis, but eGFR was lower than baseline (47.5 +/- 23.3 ml/min/ 1.73 m(2) versus 75.8 +/- 25.4 ml/min/1.73 m(2)); 38.4% of survivors had recovered basal RF: 26% of those with previous normal RF and 61% of those in KDOQI-3, respectively. At 1 year, eGFR increased to 61.9 +/- 24.4 ml/min/1.73 m(2) and remained stable later. During an 8-year median follow-up (P25:2; P75:10), 31% improved RF, 50% remained stable and 19% deteriorated. In total only 46% (n = 82) definitively recovered RF. Finally, at the end of the study period 61.6% presented some degree of renal dysfunction: 40% of those with previous normal RF developed moderate-severe renal dysfunction and 37% KDOQI-3 progressed into more severe renal failure. Only two patients needed dialysis. Regression model identified age, co-morbidities, discharge eGFR and follow-up time as independent predictors of long-term RF., Conclusions: AKI carries implication for long-term RF even in patients without pre-existing renal dysfunction. Ageing, co-morbidities and RF at discharge are determinants of the long-term functional outcome.

Background and Objectives: Different scores to predict acute kidney injury after cardiac surgery have been developed recently. The purpose of this study was to validate externally two clinical scores developed at Cleveland and Toronto., Design, Setting, Participants, & Measurements: A retrospective analysis was conducted of a prospectively maintained database of all cardiac surgeries performed during a 5-yr period (2002 to 2006) at a University Hospital in Madrid, Spain. Acute kidney injury was defined as the need for renal replacement therapy. For evaluation of the performance of both models, discrimination and calibration were measured., Results: Frequency of acute kidney injury after cardiac surgery was 3.7% in the cohort used to validate the Cleveland score and 3.8% in the cohort used to validate the Toronto score. Discrimination of both models was excellent, with values for the areas under the receiving operator characteristics curves of 0.86 (95% confidence interval 0.81 to 0.9) and 0.82 (95% confidence interval 0.76 to 0.87), respectively. Calibration was poor, with underestimation of the risk for acute kidney injury except for patients within the very-low-risk category. The performance of both models clearly improved after recalibration., Conclusions: Both models were found to be very useful to discriminate between patients who will and will not develop acute kidney injury after cardiac surgery; however, before using the scores to estimate risk probabilities at a specific center, recalibration may be needed.

Objective: To assess the incidence and prognostic value of acute renal function deterioration (ARFD) in patients with acute heart disease., Setting: Coronary Care Unit in a tertiary university hospital., Design: Retrospective study., Participants: One hundred consecutive patients admitted during 2004., Interventions: No randomized interventions were done. Diagnostic and therapeutic procedures were performed according to local protocols and current Clinical Practice Guidelines. PRIMARY VARIABLES: The primary aim of the study was to analyze the incidence of acute renal function deterioration and its effect in mortality during hospitalization. ARFD was defined as the increase of serum creatinine by 0.5 mg/dl and/or by 50% over baseline., Results: Incidence of ARFD was 26%, with a mean increase of serum creatinine of 1.5 +/- 0.9 mg/dl. ARFD was significantly associated with age, background of hypertension and chronic kidney disease. Patients with ARFD had a more complicated course, longer hospitalizations, and received fewer catheterisms. Acute renal function deterioration was associated with higher mortality during hospitalization (33% versus 6%, p = 0.002)., Conclusions: Acute renal function deterioration is frequent in patients with acute heart disease and its presence is linked with higher mortality.

Introduction: The ionic dialysance monitor allows an automated measure of Kt in each dialysis session. Bioelectrical impedance analysis (BIA) determines the total body water which it is equivalent to the urea volume of distribution (V). If the Kt, determined by ionic dialysance, is divided by the V, estimated by bioelectrical impedance, a Kt/V at the end of dialysis session (Kt/VDiBi) is obtained., Aim of the Study: To evaluate the agreement between the Kt/VDiBi and the Kt/V obtained by two simplified formulas: the monocompartimental (Kt/Vm) and the equilibrated (Kt/Ve) Daugirdas equations., Methods: The Kt/VDiBi, the Kt/Vm and the Kt/Ve were determined in 38 hemodialysis patients (27 males and 11 females) in the same hemodialysis session. The patients were on dialysis three times a week for 3.5 to 4 hours. The V was determined by monofrequency bioelectrical impedance (50 kHz) at the end of the dialysis session., Results: The Kt/VDiBi, Kt/Vm and Kt/Ve were 1.29+/-0.26, 1.54+/-0.29 and 1.36+/-0.25, respectively (p<0.001 between the Kt/VDiBi and the KtVm, and p<0.001 between the KtV/DiBi and the Kt/Ve). The intraclass correlation coefficient showed better concordance between the KtV/DiBi and the Kt/Ve (coefficient 0.88) than between the Kt/VDiBi and the KtVm (coefficient 0.65). The relative difference of the Kt/VDiBi was 8.3+/-6.4% with respect to the Kt/Ve and 18.4+/-7.8 % with respect to the Kt/Vm (p<0.001). The relative difference between the Kt/VDiBi and the Kt/Ve was lower than 15% in the 84% of the patients and lower than 10% in the 64% of the patients., Conclusions: If the V obtained by bioelectrical impedance analysis is included in the ionic dialysance monitor, we can obtain a Kt/V for each patient in real time, which is similar to the equilibrated Kt/V obtained from the Daugirdas equation.

Although renal dysfunction is common after liver transplantation, postoperative renal function after split liver transplantation (SLT) has not been well studied. Renal function immediately after surgery was analyzed retrospectively in 16 patients that received a SLT (SLT group). The results were compared with corresponding data from 31 matched patients that received a full-size liver transplant (FSLT group) during the same period. Serum creatinine (SCr) was measured before surgery, and, after transplantation, daily during the first week and at days 14, 21, and 28. Renal dysfunction (RD) was defined as the requirement for renal replacement therapy (RRT) or a 100% increase in SCr if the basal value had been <1.0 mg/dL or a 50% increase in SCr if the basal value had been >1.0 mg/dL. SCr had to be at least 1.5 mg/dL for a diagnosis of RD to be considered. The classification of RD was: mild, SCr 1.5-2.4 mg/dL; moderate, SCr 2.5-4.0 mg/dL; or severe, SCr >4.0 mg/dL (the requirement for RRT). Both donor and recipient age and cold ischemia time were lower in the SLT group than in the FSLT group (P < 0.05). Length of surgery was longer in the SLT group (P < 0.05). There were no significant differences between groups with respect to Model for End-Stage Liver Disease scores, the need for transfusions, the length of admission to the intensive care unit (ICU), survival rate, individual severity index, or sepsis-related organ failure assessment scores at the time of diagnosing RD. Immunosuppression regimens were similar in both groups. RD developed in 82% of SLT patients, but in only 58% of FSLT patients (P = not significant [NS]). Among SLT patients, RD (23.0% mild, 15.5% moderate, and 61.5% severe) was more severe (P = 0.007) than in FSLT patients (63.1% mild, 15.8% moderate, and 24.1% severe). The requirement for RRT in the SLT group (43.7%) was significantly greater (P < 0.05) than that in the FSLT group (12.9%). This finding may be due to the different incidence of sepsis in the 2 groups (SLT 37.5% vs. FSLT 9.7%; P < 0.05). In conclusion, although the number of patients studied was small, our data suggest a higher incidence of RD and a greater requirement for RRT in patients that receive a split liver graft than in those that receive a full size liver graft.

Renal ischemia/reperfusion injury (IRI) is an important cause of acute renal failure. Cellular and molecular responses of the kidney to IRI are complex and not fully understood. beta1 integrins localize to the basal surface of tubular epithelium interacting with extracellular matrix components of the basal membrane, including collagen IV. Whether preservation of tubular epithelium integrity could be a therapeutic approach for IRI was assessed. The effects of HUTS-21 mAb administration, which recognizes an activation-dependent epitope of beta1 integrins, in a rat model of IRI were investigated. Preischemic HUTS-21 administration resulted in the preservation of renal functional and histopathologic parameters. Analyses of activated beta1 integrins expression and focal adhesion kinase phosphorylation suggest that its deactivation after IRI was prevented by HUTS-21 treatment. Moreover, HUTS-21 impaired the inflammatory response in vivo, as indicated by inhibition of proinflammatory mediators and the absence of infiltrating cells. Ex vivo adhesion assays using reperfused kidneys revealed that HUTS-21 induced a significant increase of epithelial cell attachment to collagen IV. In conclusion, the data provide evidence that HUTS-21 has a protective effect in renal IRI, preventing tubular epithelial cell detachment by preserving activated beta1 integrins functions.

Unlabelled: The Diascan equipment (Hospal) measures ionic dialysance from which it derives the Kt/V. It is automatic, does not need blood samples and displays the results in real time. The aim of the present study was to compare the Diascan Kt/V with the Kt/V obtained with four simple formulas: two based on a single pool model of urea kinetics (Lowrie 1983 and Daugirdas 1993) and the other based on the two pool model (Maduell formulation applied to Lowrie Kt/V and that proposed by Daugirdas 1995). We have analyzed the inter-method variability, the degree of relationship among the different procedures for Kt/V calculation and the intra-individual variability. The intermethod variability between Kt/V Diascan and Kt/V calculated by the four simple formulas were studied in one hemodialysis session in 19 patients. The Kt/V Diascan was statistically different from that calculated by the four formulas (1,021 +/- 0.140 Diascan vs 1,147 +/- 0.124 for Lowrie-83; vs 1,373 +/- 0.164 for Daugirdas-93; vs 0.963 +/- 0.105 for Maduell and vs 1,173 +/- 0.143 for Daugirdas-95, p < 0.01). The lowest inter-method variability was obtained with the Maduell's Kt/V (relative difference 9%) but even in this case 37% of patients had a variability above 10%. The correlation coefficient was not high enough to allow an estimation of the different Kt/V measurements from the Diascan Kt/V by a regression equation. To study the individual relationship between the Diascan Kt/V and the Kt/V calculated by the four formulations, we have determined the Kt/V every 30 minutes in one hemodialysis session in 30 patients. In all patients we observed a good relationship between the Diascan Kt/V and the other four (correlation coefficient of 0.9952 for Lowrie-83, 0.9976 for Daugirdas-93, 0.9961 for Maduell and 0.9971 for Daugirdas-95); with these correlation coefficientes it was possible to derive regression equations and to obtain an estimation of the four Kt/V's from the Diascan Kt/V. To study the individual variability of each procedure used in the Kt/V calculations we determined the coefficient of variation of the different methods in 5 consecutive hemodialysis sessions performed under identical conditions in 19 patients. The coefficient of variation was 3.7 +/- 1.8% for the Diascan Kt/V; 6.0 +/- 2.8 for the Lowrie-83 Kt/V; 5.8 +/- 2.4 for the Daugirdas-93 Kt/V; 6.5 +/- 2.6% for the Maduell Kt/V; and 5.7 +/- 2.2% for the Daugirdas-95 Kt/V (p < 0.01 between the Diascan Kt/V and the other four)., Conclusions: Although the Diascan Kt/V was statistically different from the other four Kt/V's calculated by the usual formulas, the Diascan Kt/V has an excellent correlation with all of them and showed a lower intra-individual variability. It is possible to obtain an estimation of the calculated Kt/V for each patient by linear regression equation.

Objective: To study the phenomenon of biomineralization in an experimental model of lithogenesis by percutaneous renal punction without laparotomy and no antibiotics., Methods/results: The study comprised 4 Brown-Norway rats. Nanobacteria inoculum (X, 2X and 4X) was administered to three rats and the remaining one was used as control. The analytical and radiological findings showing the development of obstructive pyelocaliceal lithiasis in the kidneys of rats no. 2 and 3 are presented., Conclusions: Translumbar percutaneous renal puncture has permitted performing laparotoy without antibiotic coverage, which was the main difficulty of the experimental model of lithogenesis. Nanobacteria were cultured successfully, but not without difficulty, and formation of calculi in the rat pyelocaliceal system was achieved. This experimental model will provide further insight into lithogenesis and will allow us to find the answers to some of the many questions concerning this condition that remain.

Introduction: Ionic dialysance is a method of continuous on-line monitoring of delivered dialysis without blood sampling. To compare the results obtained by ionic dialysance and those obtained by the traditional measurements of the dialysis dose, it is necessary to know the relationship between the ionic dialysance and urea clearance., Material and Methods: Ionic dialysance and the urea clearance were determined in 18 patients (13 dialyzed with cuprophan and 5 patients with AN69). Urea clearance was measured by 6 different methods: urea clearance in whole blood calculated with the arteriovenous difference in the urea concentration rates and the arterial flow measured by the rolling pump (KBAVb) or by ultrasounds (KBAVu); urea clearance in whole blood measured by the urea concentration in the dialysate (KBD); urea blood water clearance measured by the arteriovenous difference in the concentration rates using the arterial flow measured by the roller pump (KwBAVb) or by ultrasounds (KwBAVu) and urea blood water clearance measured by the urea concentration in dialysate (KwBD)., Results: The mean arterial flow measured by the roller pump was 314.4 +/- 16.2 ml/min and 275.1 +/- 13.8 ml/min when measured by ultrasounds (p < 0.001). The data of ionic dialysance and urea clearances were as follow (ml/min): ionic dialysance 185.6 +/- 11.7; KBAVb 245.7 +/- 15.7; KBAVu 215.4 +/- 13.2; KBD 231.6 +/- 13.1; KwBAVb 218.1 +/- 14; KwBAVu 191.2 +/- 11.8; KwBD 183.1 +/- 11.7. The absolute difference of ionic dialysance with the KwBAVu was 8.4 +/- 6 ml/min (range between -17.8 and 11.5 ml) and with the KwBD was 7.6 +/- 5.4 ml (range between -12.9 and 21.4 ml)., Conclusions: There was a relationship between ionic dialysance and urea blood water clearance. The best concordance was obtained when the clearance was calculated with the urea concentration of dialysate, or with the arteriovenous difference of the urea concentration rates and the arterial blood flow measured by ultrasounds.

Purpose: To study visual quality and postoperative complications after phacoemulsification and hydrogel (Hydroview, H60M) IOL implantation, at one year postoperatively., Methods: Prospective study of 60 patients. After capsulorhexis and phacoemulsification, patients received a foldable hydrogel lens or a PMMA IOL. Postoperative examinations were made on 7, 30, 60, 180 and 360 th day. We measured distance visual acuity, contrast sensitivity, keratometry, anterior capsule fibrosis and the presence of other postoperative complications., Results: Small incision and foldable IOL provided faster visual rehabilitation, however visual acuity was better with PMMA lens (F=4.33, p<0.5) at 12 months after surgery. Contrast sensitivity at high spatial frequencies was significantly better in PMMA lens group. Anterior capsule fibrosis is more important in hydrogel IOL group (chi(2) = 10.87, gl = 3, p<0.025). Other complications in the two groups were few and comparable., Conclusions: Hydrogel IOL provided good visual results and rapid visual recovery. However visual results are unstable. Anterior capsule fibrosis and on anterior intraocular lens surface fibrosis are common complications with hydrogel lens.

Although patients with acute renal failure (ARF) are now older and sicker than in the past, mortality remains constant or even slightly lower, which suggests a better management of the syndrome. Several clinical conditions, mainly assisted respiration, hypotension, oliguria, coma and jaundice, have a detrimental effect on outcome. Previous health status, original disease, a hospital and/or ICU start of the ARF, and age of the patient also seem to affect outcome of these patients. ARF observed in the ICU setting has a poorer prognosis than the ARF treated in other hospital areas. This is because of the higher number of associated organ failures observed in the ICU. Estimation of outcome could be done either using specific ARF or general ICU score systems. They allow risk stratification of the patients, and some of them give an individual prognosis that at present should not be used for a withdrawal decision. Functional outcome of ARF is usually good, although some patients need to be maintained on chronic dialysis.

Objectives: There is a tendency to treat older people with Acute Renal Failure (ARF) less aggressively because of the presumed less acceptable end results. This has not been proved, and their prognosis may be similar to that found in the younger population. There are no studies on the incidence, causes, and evolution of ARF in patients 80 years of age and older., Design: A multicenter, prospective, longitudinal study., Setting: The 13 hospitals with nephrology units that serve the 4.2 million people in Madrid, Spain., Measurements: A number of demographic, clinical, and therapeutic variables were studied in each case., Results: One hundred three episodes of ARF occurred in patients 80 years of age and older (Group 1), 256 in patients aged 65 to 79 years (Group 2), and 389 in people younger than age 65 (Group 3). Acute tubular necrosis was diagnosed in 39% of cases in Group 1, in 48% in Group 2, and in 55% in Group 3 (P = .004, 1 vs 3); prerenal ARF was diagnosed in 30%, 28%, and 21% (P = .054, 1 vs 3) and obstructive ARF in 20%, 11%, and 7% (P < .001, 1 vs 3) of cases, respectively. Serum creatinine at admission, peak values, values at discharge or death, duration of both admission and ARF episode, and mortality were similar in all groups. In stratified analysis, relative risk for mortality in patients aged more than 80 years was 1.09 [95%CI 0.86,1.36 (P = .562)], and in those aged 65 to 79 it was 0.99 [95%CI 0.83,1.18 (P = .954)] compared with patients aged less than 65 years. Risk of death was also similar when only acute tubular necrosis cases were considered. Sustained hypotension was associated with higher mortality (44% of nonsurviving older persons vs 9% of survivors, P < .001)., Conclusion: Age is not a particularly poor prognostic sign, and outcome seems to be within acceptable limits for very old patients with ARF. Acute dialysis should not be withheld from patients solely because they are more than 80 years of age.

Acute renal failure (ARF) is at a crossroads between nephrology and intensive care medicine. However, there seems to be wide differences between the ARF observed in the intensive care unit (ICU) compared to that observed in other areas of the hospital, particularly when examining the mortality rate. Among the ICU patients the 70% mortality rate is higher to the 50% found in an overall series of studies. Recently, Druml proposed that there is a changing trend in the clinical spectrum of ARF as a convincing reason to justify these differences. According to him, we are moving from an ARF seen as a mono-organ failure to another one observed in a multiorgan dysfunction syndrome (MODS) context. Although extremely coherent, this hypothesis has not been fully confirmed in a prospective study. In fact, most authors seem to look at the problem from opposite sides of the river, either from the critical medicine or the nephrological bank. To the best of our knowledge, only one retrospective study has dealt with this topic by comparing outcome of ARF in ICU and non-ICU patients. In this article we aim to overcome this problem by reviewing the data of the prospective epidemiological ARF study carried out in Madrid using two different approaches: (1) comparing the ARF cases observed in the ICU setting with those ARF studied outside the ICU, and (2) comparing the outcome of isolated ARF with the outcome of ARF as part of a MODS in patients treated in both settings.

There are very limited data on overall epidemiology of ARF. It is crucial to know the incidence, etiology and clinical feature of ARF to promote prevention strategies and to implement adequate resources for the management of this entity. During a nine month period, a collaborative prospective protocol with 98 variables was developed to assess all ARF episodes encountered in the 13 tertiary-care hospitals in Madrid, Spain (covering 4.2 million people of over 14 years of age). ARF was considered when a sudden rise in serum creatinine concentration (SCr) to more than 177 mumol/liter was found in patients with normal renal function, or when the sudden rise (50% or more) was observed in patients with previous mild-to-moderate chronic renal failure (SCr < 264 mumol/liter). Of the 748 cases of ARF studied, 665 episodes presented in inhabitants from the Madrid area. This gives an overall incidence of ARF of 209 cases per million population (p.m.p.; 95% CJ 195 to 223). The incidence of acute tubular necrosis (ATN) was 88 cases p.m.p. (95% CI 79 to 97), prerenal ARF 46 p.m.p (95% CI 40 to 52), acute-onset chronic ARF 29 p.m.p. (95% CI 24 to 34), and obstructive ARF 23 p.m.p. (95% CI 19 to 27). The mean age was 63 +/- 17 years. The most frequent causes of ARF were ATN (45%), prerenal (21%), acute-onset chronic renal failure (12.7%) and obstructive ARF (10%). Renal function was normal at admission in 48% of patients who later developed ARF. Mortality (45%) was much higher than that of the other patients admitted (5.4%, P < 0.001). This real outcome correlated extremely well with the expected outcome calculated through out the severity index of ARF (SI) 0.433 +/- 0.246 (mean +/- SD). In 187 cases, mortality was attributed to underlying disease, thus corrected mortality due to ARF was 26.7%. Dialysis was required in 36% of patients, and was associated with a significantly higher SI of ARF (0.57 +/- 0.23 vs. 0.35 +/- 0.19, P < 0.001) and mortality (65.9 vs. 33.2%, P < 0.001). Mortality in patients hemodialyzed with biocompatible synthetic membranes (N = 50) was similar to that observed with cellulosic ones (N = 84; 66% vs. 59.5%, NS). Mortality was higher in patients with coma, assisted respiration, hypotension, jaundice (all P < 0.001) and oliguria (P < 0.02). This study gives, for the first time, the incidence of all forms of ARF in a developed country. ARF is iatrogenically induced at a high rate by modern medicine. Prevention strategies, particularly in the perioperative period, are needed to decrease its impact.

Background: To describe the clinical features and the final diagnosis of patients infected with human immunodeficiency virus who presented fever of unknown origin., Methods: Retrospective study, from November 1989 to January 1994, of all patients infected with HIV who had fever of unknown origin and who were admitted to a community hospital in a Mediterranean area in Alicante (Spain). Fever of unknown origin was defined as fever exceeding 38.3 degrees C lasting for at least three weeks with no diagnosis in the first three days of hospitalization after fulfilling clinical exam, three blood cultures, acid-fast bacilli stain in sputum and chest-X-ray., Results: Of a cohort of 231 patients, 27 (12%) were evaluated because of fever of unknown origin during their follow-up. Patients' mean age was 31 years (interval, 22-75) and intravenous drug use (81%) was the most common risk factor for HIV infection. A total of 31 episodes of fever of unknown origin were reviewed. Twenty-three (74%) episodes occurred in patients with less than 200 CD4 lymphocytes/mm3. A final diagnosis of fever of unknown origin was achieved in 24 (77%) episodes: visceral leishmaniasis (n = 11), tuberculosis (n = 9), non-Hodgkin's lymphoma (n = 1), CNS toxoplasmosis (n = 1), cryptococcal meningitis (n = 1) and drug adverse reaction (n = 1)., Conclusions: HIV-infected patients with fever of unknown origin very often show severe immunodeficiency. Cryptococcal antigen testing should be carried out in the initial evaluation of fever of unknown origin in HIV-infected patients. In our area, 64% of episodes of fever of unknown origin were caused by visceral leishmaniasis or tuberculosis.

Limited attention has been paid to the composition of the small amounts of urine that are frequently produced by patients with acute renal failure (ARF) of vascular origin. We have investigated the value of basic urinary parameters in the early diagnosis of total or partial acute renal artery occlusion (ARAO). We have reviewed the records of 30 patients with ARF: group 1 (n = 10) had total ARAO; group 2 (n = 10) had unilateral ARAO with a contralateral functioning kidney, and group 3 (n = 10) had hemodynamically mediated ARF subsequent to a major vascular abdominal surgical procedure, without arterial thrombosis. Serum sodium, potassium, urea, creatinine and osmolality, as well as urinary sodium, potassium, urea, creatinine and osmolality, were determined by standard techniques, and the fractional excretion of sodium (FENa) was calculated. Serum parameters were similar in all groups. Urinary sodium and FENa were higher in group 1 than in the other groups (p < 0.01), while urinary potassium was lower (p < 0.05). Urinary urea (p < 0.01) and osmolality (p < 0.05) were higher in group 2 than in the other groups, revealing a prerenal pattern in some cases. Serum and urinary concentrations of sodium, urea and creatinine and osmolality were similar in group 1, while respective serum and urinary concentrations and osmolality were different from each other in the other groups. Analysis of urine provides a useful diagnostic tool in ARF of vascular origin. When urinary concentrations of sodium, urea and creatinine are similar to those in serum and FENa approaches 100%, the strong likelihood of total ARAO should be acknowledged, and renal arteriography is mandatory.