Gustavo Greloni

Cutaneous necrosis by calcific uremic arteriolopathy.

Background  Calcific uremic arteriolopathy is a rare and serious disorder characterized by systemic medial calcification of the arteries and tissue ischemia. Most often it is found in patients with chronic renal failure on dialysis and in renal transplant recipients with secondary hyperparathyroidism.

Assessment of fractional excretion of urea for early diagnosis of cardiac surgery associated acute kidney injury

Abstract Background: Acute kidney injury (AKI) is a common complication after cardiac surgery (CS). Recently, neutrophil gelatinase-associated lipocalin (NGAL) was shown to predict AKI development earlier than serum creatinine, but it is not widely used in clinical practice. Fractional excretion of urea (FeU) has been referred to as a useful tool to discriminate between prerenal and established AKI. The aim of our study is to evaluate the sensitivity and specificity of FeU, in the early diagnosis of AKI in patients undergoing CS. Methods: We performed a prospective study on adults undergoing CS. AKI was defined by AKIN criteria. Individuals suffering from CKD, were excluded. Sensitivity and specificity of FeU, fractional excretion of sodium (FeNa) and urine NGAL, measured at 1, 6 and 24 h following CS, were assessed. Results: We included 66 patients (26% female) aging 68 ± 11 years. AKI prevalence was 24% and mortality was 3.28%. Patients with AKI had a significantly lower FeU compared to those without AKI (23.89 ± 0.67% vs. 34.22 ± 0.58%; p < 0.05) 6 h after CS, but not at the 1- and 24-h time points. NGAL was also statistically significant between both groups. FeU showed a 75% sensitivity and 79.5% specificity; the AUC was 0.786. ROC analysis of FeU and NGAL yielded similar values (p = NS). Conclusion: FeU is useful as an early biomarker to predict AKI after CS and it is comparable to the new biomarker NGAL.

Refractory hyperkalemia in peritoneal dialysis

In peritoneal dialysis (PD) patients hyperkalemia is an unusual complication (0.8% in CAPD) [1], while hypokalemia is frequent, affecting approximately 30% of this population, even when the potassium removal by dialysis does not justify this phenomenon [2, 3]. The latter situation could be due to the shift of potassium into the intracellular space, probably because of the insulin released during the continuous glucose infusion from the dialysis solution [4]. Patients on CAPD have been shown to have a higher intracellular potassium content than hemodialysis patients [5]. In this letter we report two PD patients who developed severe and persistent hyperkalemia which required several consecutive dialysis sessions before the potassium levels returned to normal. This complication is rare in patients on chronic dialysis in the absence of any source of internal release of potassium such as bleeding or cytolysis. Both patients were young women (27 and 30 years of age); the first was on CAPD for five months after five years of renal transplant and the other was on CAPD for four years. They were anuric but adequately dialyzed with 9 L/day and 11 L/day respectively and without any previous episode of hyperkalemia. In order to lose weight, both patients started on a diet based on fruit and vegetables without the knowledge of the medical staff. Hyperkalemia was detected on a routine, clinical visit. They had no evidence of infection, bleeding, hemolysis, rhabmyolysis or any other kind of cell breakdown. Both patients were treated initially with salbutamol nebulization and frequent exchanges of manual peritoneal dialysis. However, because hyperkalemia persisted we decided to provide a more effective dialysis. The first patient was dialyzed with a 4–8 cycler session (2 L/hour, K free dialysate) and the other with a 2–3 hours of hemodialysis with a 2.2 potassium mmol/l dialyzate. In both cases, these measTable 1. Change in plasma potassium (mM/L) in the course of treatment

Factores determinantes de una baja dosis de hemodiálisis establecida por dialisancia iónica en pacientes críticos con insuficiencia renal aguda

BACKGROUND Estimating the dialysis dose is a requirement commonly used to assess the quality of renal replacement therapy (RRT) in patients with chronic kidney disease (CKD). In patients with acute kidney injury (AKI), this value is not always evaluated and it has been estimated that the prescribed dose is seldom obtained. Reports addressing this issue in AKI individuals are scarce and most have not included an adequate number of patients or treatments, nor were patients treated with extended therapies. Kt values obtained by the ionic dialysance method have been validated for the evaluation of the dialysis dose and it has also been shown that, compared with Kt/V, this is the most sensitive strategy for revealing inadequate dialysis treatment in critically ill AKI individuals. The main aim of this study was to assess the difference between the prescribed and the administered dialysis dose in critically ill AKI patients, and to evaluate what factors determine this gap using Kt values assessed through ionic dialisance. MATERIAL AND METHOD Data from 394 sessions of renal replacement therapy in 105 adult haemodialysis (HD) patients with oliguric acute kidney injury and admitted to ICU were included in this analysis. RRT was carried out with Fresenius 4008E dialysis machines equipped with on-line clearance monitoring (OCM® Fresenius), which use non-invasive techniques to monitor the effective ionic dialysance, equivalent to urea clearance. The baseline characteristics of the study population as well as the prescription and outcome of RRT were analysed. These variables were included in a multivariate model in which the dependent variable was the failure to obtain the threshold dose (TD). RESULTS The main baseline characteristics of the study population/treatments were: age 66 ± 15 years, 37% female, most frequent cause of AKI: sepsis (70%). Low BP and/or vasoactive drug requirement (71%), mechanical ventilation (70%) and average individual severity index: 0.7 ± 0.26. Two hundred and one intermittent HD (IHD) and 193 extended HD (EHD) sessions were performed; the most frequently used temporary vascular access was the femoral vein catheter (79%). Prescribed Kt was 53.5 ± 14L and 21% of prescriptions fell below the TD. Sixty-one percent of treatments did not fulfill the TD (31 ± 8L) compared with 56 ± 12L obtained in the subgroup that achieved the target. Compared to IHD, EHD provided a significantly larger Kt (46 ± 16L vs 33L ± 9L). Univariate analysis showed that inadequate compliance was associated with age (>65y), male gender, intra-dialytic hypotension, low Qb, catheter line reversal, and IHD. The same variables with the exception of age and gender were independently associated in the multivariate analysis. CONCLUSIONS The dialysis dose obtained was significantly lower than that prescribed. EHD achieved values closer to the prescribed KT and significantly higher than in IHD. Ionic Kt measurement facilitates monitoring and allows HD treatments to be extended based upon a previously established TD. Besides the chosen strategy to dispense the dose of dialysis, a well-functioning vascular access allowing for optimal blood flow and other approaches aimed at avoiding hemodynamic instability during RRT are the most important factors to achieve TD, mainly in elderly male patients. The dialysis dose should be prescribed and monitored for all critically ill AKI patients.

H1N1 infection and acute kidney injury in the critically ill.

Sir, Acute renal failure due to viral infections rarely occurs. We assessed the development of acute kidney injury in critically compromised patients due to H1N1 influenza virus. All patients with PCR-confirmed diagnosis of H1N1 infection between May and July 2009 were retrospectively studied. Thereafter, the risk factors associated with the development of acute renal injury, the requirements of acute haemodialysis and death were analysed. Twenty-two subjects with H1N1 pneumonia were included: age: 52.91 ± 18.89 years; gender: males 11 (50%); chronic airway disease: 9 (41%); oncohaematological disease: 8 (36.7%); cardiovascular disease: 5 (22.7%); chronic renal insufficiency: 4 (18.2%); obesity: 3 (13.6%); concomitant pregnancy: 2 (9.1%); diabetes mellitus: 2 (9.1%); previous influenza A vaccination: 9 (41%). All patients received oseltamivir within 48 h of presumed diagnosis. Seventeen patients (77.3%) developed initial fever. Six patients (27.3%) required non-invasive ventilation assistance and 15 (68.2%) received invasive ventilatory support. The mean days on mechanical respiratory assistance were 11 ± 10.35. The arterial partial pressure of oxygen/fraction of inspired oxygen ratio was 140.11 ± 83.03 mmHg. Inotropic drugs were administered to 15 patients (68.2%). Fourteen patients (63.6%) developed acute kidney injury. The mean highest creatinine levels were 2.74 ± 2.83 mg/dL. Four patients (18.2%) needed renal replacement therapy with a mean duration of 15 ± 12 days. Six patients (42.9%) recovered renal function. Significant differences between patients with and without acute kidney injury included, respectively, pregnancy, 2 versus 0, P < 0.05; non-haematological immunosuppression, 6 versus 0, P < 0.05; APACHE score, 26.64 ± 2.51 versus 14.2 ± 1.63, P < 0.01; SOFA score, 9.21 ± 1.01 versus 4 ± 0.94, P < 0.01; MURRAY score, 0.55 ± 0.34 versus 1.34 ± 2.46, P < 0.05; mechanical respiratory assistance, 12 versus 2, P < 0.05; days on mechanical ventilation, 8.5 versus 25.66, P < 0.05; use of inotropic drugs, 12 versus 3, P < 0.05; and lower platelet levels, 91828 ± 18446 versus 149 250 ± 24 181, P < 0.05. Haemodialysis requirements were associated with elevated SOFA scores (12.25 ± 1.75 versus 6.22 ± 0.8, P < 0.05), elevated creatine phosphokinase (933 ± 436.6 versus 189.9 ± 79.3 U/L, P < 0.05) and alanine transferase levels (843.3 ± 778.8 versus 85.33 ± 17.4 U/L, P < 0.05). Twelve patients died (54.6%), 10 of whom had acute renal failure (83.3%) and 3 had been on acute haemodialysis (25%). Mortality was associated with higher APACHE, SOFA and Murray scores, a higher oseltamivir dose (253.1 ± 25.8 versus 183.8 ± 27.6 mg/day, P < 0.05), lower oxygen inspired fraction/alveolar pressure ratio (99.3 ± 12.2 versus 196.3 ± 33.9 mmHg, P < 0.01), thrombocytopaenia (88 966 ± 22 977 versus 141 200 ± 17 282 mm3, P < 0.05), hypoalbuminaemia (1.82 ± 0.1 versus 2.61 ± 0.2 g/dL, P < 0.01), acute renal failure (10 versus 4, P < 0.05), oligoanuria (5 versus 0, P < 0.05) and lack of recovery of renal function (2 versus 4, P < 0.01). Three out of four (75%) haemodialysed patients died. In summary, in the critically ill due to H1N1 pneumonia, renal insufficiency was a frequent complication, demanding renal replacement therapy in 18% of cases. The necessity of haemodialysis was associated with an elevated risk of death. Mortality was mainly associated with multiple organ failure, oligoanuria, acute renal injury and a lack of recovery of renal function. Rhabdomyolysis may play a role in renal dysfunction, regardless of CK levels [1–4]. Conflict of interest statement. None declared.

Lesión renal aguda en Latinoamérica en la era del big data

Fernando Lombi, Carlos Federico Varela, Ricardo Martinez , Gustavo Greloni, Vicente Campolo Girard y Guillermo Rosa Diez a Servicio de Nefrología, Hospital Británico de Buenos Aires, Buenos Aires, Argentina b Servicio de Nefrología, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina c Servicio de Nefrología, Hospital Churruca Visca Buenos Aires, Buenos Aires, Argentina d Servicio de Terapia Intensiva, Clínica Pasteur, Neuquén, Argentina