Sue Robertson

Renal impairment after high-dose flucloxacillin and single-dose gentamicin prophylaxis in patients undergoing elective hip and knee replacement

BACKGROUND Following advice from the Scottish Antimicrobial Prescribing Group, we switched our antibiotic prophylaxis for elective hip and knee replacement surgery from cefuroxime to flucloxacillin with single-dose gentamicin in order to reduce the incidence of Clostridium difficile associated diarrhoea (CDAD). A clinical impression that more patients subsequently developed acute kidney injury (AKI) led us to examine this possibility in more detail. METHODS We examined the incidence of AKI in 198 consecutive patients undergoing elective hip or knee surgery. These patients were given the following prophylactic antibiotics: cefuroxime (n = 48); then high-dose (HD) flucloxacillin (5-8 g) with single-dose gentamicin (n = 52); then low-dose (LD) flucloxacillin (3-4 g) with single-dose gentamicin (n = 46) and finally cefuroxime again (n = 52). RESULTS Patients receiving HD flucloxacillin required more vasopressors during surgery (P = 0.02); otherwise, there were no statistically significant differences in pre- and peri-operative characteristics between the four groups. The proportion of patients with any form of AKI by RIFLE criteria was first cefuroxime (8%), HD flucloxacillin with gentamicin (52%), LD flucloxacillin with gentamicin (22%) and second cefuroxime (14%; P < 0.0001). Odds ratios for AKI derived from a multivariate logistic regression model, adjusted also for sex and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, with the first cefuroxime group as a reference category were: HD flucloxacillin with gentamicin 14.53 (4.25-49.71); LD flucloxacillin with gentamicin 2.96 (0.81-10.81) and second cefuroxime 2.01 (0.52-7.73). Three patients required temporary haemodialysis. Biopsies in two of these showed acute tubulo-interstitial nephritis. All three patients belonged to the HD flucloxacillin with gentamicin group. None of the patients developed CDAD. CONCLUSIONS We have shown an association between the prophylactic antibiotic regimen and subsequent development of AKI following primary hip and knee arthroplasty that appeared to be due to the use of HD flucloxacillin with single-dose gentamicin. We found no evidence to suggest that this association was confounded by any of the co-variates we measured.

How to routinely collect data on patient-reported outcome and experience measures in renal registries in Europe: an expert consensus meeting

Despite the potential for patient-reported outcome measures (PROMs) and experience measures (PREMs) to enhance understanding of patient experiences and outcomes they have not, to date, been widely incorporated into renal registry datasets. This report summarizes the main points learned from an ERA-EDTA QUEST-funded consensus meeting on how to routinely collect PROMs and PREMs in renal registries in Europe. In preparation for the meeting, we surveyed all European renal registries to establish current or planned efforts to collect PROMs/PREMs. A systematic review of the literature was performed. Publications reporting barriers and/or facilitators to PROMs/PREMs collection by registries were identified and a narrative synthesis undertaken. A group of renal registry representatives, PROMs/PREMs experts and patient representatives then met to (i) share any experience renal registries in Europe have in this area; (ii) establish how patient-reported data might be collected by understanding how registries currently collect routine data and how patient-reported data is collected in other settings; (iii) harmonize the future collection of patient-reported data by renal registries in Europe by agreeing upon preferred instruments and (iv) to identify the barriers to routine collection of patient-reported data in renal registries in Europe. In total, 23 of the 45 European renal registries responded to the survey. Two reported experience in collecting PROMs and three stated that they were actively exploring ways to do so. The systematic review identified 157 potentially relevant articles of which 9 met the inclusion criteria and were analysed for barriers and facilitators to routine PROM/PREM collection. Thirteen themes were identified and mapped to a three-stage framework around establishing the need, setting up and maintaining the routine collection of PROMs/PREMs. At the consensus meeting some PROMs instruments were agreed for routine renal registry collection (the generic SF-12, the disease-specific KDQOL™-36 and EQ-5D-5L to be able to derive quality-adjusted life years), but further work was felt to be needed before recommending PREMs. Routinely collecting PROMs and PREMs in renal registries is important if we are to better understand what matters to patients but it is likely to be challenging; close international collaboration will be beneficial.

Bilateral renovascular disease causing cardiorenal failure

Consider renovascular disease in patients with cardiorenal failure The association between heart failure and bilateral renovascular disease was first recorded in 1988 and has since been the subject of numerous reports.1–12 Acute or “flash” pulmonary oedema is most commonly described, but chronic heart failure can also occur. Heart failure is thought to arise when the kidneys, “protected” by bilateral stenoses, fail to mount a pressure natriuresis to high arterial pressure. The syndrome is therefore characterised by fluid retention rather than ventricular failure. Clinical clues include the association of cardiac and renal failure with hypertension, widespread vascular disease, inequality of renal size (1.5 cm difference) on ultrasonography, and a reversible increase in serum creatinine concentrations after taking an angiotensin converting enzyme inhibitor.13 A proportion of patients with this clinical syndrome may be cured by renal revascularisation. We report on such a case. A 75 year old woman with moderate left ventricular systolic dysfunction after an inferior myocardial infarction required temporary haemodialysis when she became moribund with cardiorenal failure while receiving an angiotensin converting enzyme inhibitor. Blood pressure was 102/58 mm Hg, and she had gross pulmonary and peripheral oedema. Her serum creatinine concentration was 731 µmol/l (reference range 70-120 µmol/l). She had had three less severe episodes of cardiorenal failure in the previous 15 months, each associated with an angiotensin converting enzyme inhibitor (fig 1). On ultrasonography the left kidney measured 7.0 cm and the right kidney 9.5 cm. Arteriography showed occlusion of the …

Comparison of combined urea and creatinine clearance and prediction equations as measures of residual renal function when GFR is low

BACKGROUND UK, US and European guidelines recommend the decision to initiate dialysis should be based on a combination of measurements of kidney function, nutritional status and clinical symptoms. Such recommendations assume an accurate and reproducible measure of glomerular filtration rate (GFR). METHODS Prospective study of 97 patients with chronic kidney disease (CKD) and serum creatinine >200 micromol/l (2.26 mg/dl) who between them contributed 388 24 h urine collections. Our main outcome measure was the number of patients with low residual renal function identified by different tests, using widely accepted thresholds. We calculated sensitivity, specificity, positive and negative predictive values and receiver operating characteristic curves for each comparison using a combined urea and creatinine clearance of <15 ml/min to indicate the likely presence of end stage renal disease (CKD stage 5). RESULTS Seventy five patients had a combined urea and creatinine clearance <15 ml/min during the study. Using the highest measurement of serum creatinine for each patient, the best of the prediction equations was the 4-variable modification of diet in renal disease (MDRD) equation (area under ROC curve 0.93). This was followed by Kt/V (AUC 0.91) and Cockroft Gault with and without correction for ideal body weight (AUC 0.89). Further analyses showed that the 4-variable MDRD equation had higher NPV (64%) but lower PPV (89%) than the other tests (NPV 40-49%, PPV 92-100%), for identifying patients whose combined clearance was <15 ml/min. CONCLUSION The 4-variable MDRD formula is currently the best available prediction equation for GFR, but will nevertheless over estimate residual renal function when this is significantly impaired in up to 36% cases. Collection of 24 h urine samples may still have a role in the assessment of patients with stages 4 and 5 CKD.

Recovery of renal function after 90 d on dialysis: implications for transplantation in patients with potentially reversible causes of renal failure

Abstract:  Background:  Late recovery of renal function in patients requiring dialysis is a well recognized but uncommon phenomenon. Moves to increase the number of live donor transplants and the recognition that early transplantation is associated with better graft survival means it is possible that patients who are going to recover renal function may be transplanted unnecessarily.

Fulminating varicella despite prophylactic immune globulin and intravenous acyclovir in a renal transplant recipient: should renal patients be vaccinated against VZV before transplantation?

Abstract:  We describe a case of fulminating varicella despite prophylactic immune globulin and intravenous acyclovir in a renal transplant recipient. This promoted a survey of all 383 adult patients awaiting a renal transplant in Scotland, which showed a low level of Varicella zoster virus (VZV) awareness but a willingness to consider vaccination if non immune. 359/363 serum samples tested were seropositive for VZV antibody giving a susceptibility to VZV of 1.2%. Although data on vaccination in adults with chronic kidney disease are limited, expert opinion is of the view that the benefits of vaccinating immunocompetent seronegative patients before transplantation are likely to outweigh the risks. We believe that adult patients awaiting a transplant in the UK should be tested for their susceptibility to VZV and that early vaccination should be offered to those who are both immunocompetent and seronegative.

Symptomatic fracture risk in the renal replacement therapy population

Background Bone fractures are an important cause of morbidity and mortality in patients on renal replacement therapy (RRT). The aim of this multicentre observational study was to quantify the incidence of radiologically proven bone fracture by anatomical site in prevalent RRT groups and study its relationship to potential risk factors. Methods We performed a retrospective analysis of electronic records of all 2096 adults prevalent on RRT in the West of Scotland on 7 July 2010 across all hospitals (except one where inception was 1 August 2011) to identify all subsequent radiologically proven fractures during a median 3-year follow-up. Results There were 340 fractures, with an incidence of 62.8 per 1000 patient-years. The incidences were 37.6, 99.2 and 57.6 per 1000 patient-years in the transplant, haemodialysis (HD) and peritoneal dialysis (PD) groups, respectively (P < 0.05). In the multivariable model, age and HD (relative to transplant or PD) were independently associated with increased risk of fractures, while primary glomerular disease, increasing serum albumin and taking alfacalcidol or lanthanum were associated with decreased risk. In a multivariable model of only HD patients, age was independently associated with an increased risk of fractures, while glomerular disease, high serum albumin and being on alfacalcidol and lanthanum were associated with decreased risk. In a multivariable model in transplant patients, there were no significant independent predictors of fracture. Conclusions The risk of symptomatic bone fracture is high in RRT patients and is ∼2.5 times higher in HD than in renal transplant patients, with the increased risk being independent of baseline factors. Fracture risk increases with age and lower serum albumin and is reduced if the primary renal diagnosis is glomerular disease. The possible protective role of alfacalcidol and lanthanum in HD patients deserves further exploration.

Chronic kidney disease presenting acutely: presentation, clinical features and outcome of patients with irreversible chronic kidney disease who require dialysis immediately

Background Patients with irreversible chronic kidney disease who require dialysis immediately are a subset of ultra late referrals for whom the term chronic kidney disease presenting acutely might usefully be applied. Although well known to nephrologists and recognised as a specific group with considerable problems, little has been written about them. Objective To describe the presentation, clinical features and outcome of irreversible chronic kidney disease presenting acutely, with particular reference to nausea and vomiting as presenting symptoms. Method and results Review of 202 consecutive patients with irreversible chronic kidney disease who had dialysis between 1996 and 2006 showed that 15 (7%) had required dialysis immediately or within 7 days of presentation. Analysis of 14 available case records showed eight avoidable late referrals: previous evidence of renal failure in six, and two patients with diabetes who had not had their renal function checked. Gastrointestinal symptoms were common and led to further delays in diagnosis, with three patients having endoscopy requested before their bloods were checked. Physical and psychological morbidity associated with this form of presentation was high. Conclusions Chronic kidney disease presenting acutely is not uncommon, often avoidable and associated with adverse outcomes. The identification, follow-up and appropriate referral of patients with raised serum creatinine is likely to reduce its incidence. Nausea and vomiting may occur sufficiently frequently in advanced renal failure to justify measuring renal function before proceeding to endoscopy when patients present with gastrointestinal symptoms.

Chronic kidney disease rather than illness severity predicts medium- to long-term mortality and renal outcome after acute kidney injury

BACKGROUND Acute kidney injury (AKI) requiring renal replacement therapy (RRT) continues to be associated with a hospital mortality of ∼50%. Longer-term outcomes have been less well studied. We sought to determine the influence of ventilation and of underlying chronic kidney disease (CKD) on medium and longterm mortality and renal outcomes. METHODS All patients requiring RRT for AKI in south west Scotland between 1 January 1994 and 31 December 2005 were followed prospectively. Survival of patients who were and were not ventilated and of those with and without underlying CKD was compared by odds ratio (OR), adjusting for age and sex. Renal outcomes were determined by interrogation of our biochemistry database. RESULTS Three hundred and ninety-six patients with AKI received RRT. One hundred and seventy-six (44%) were ventilated and 98 (25%) had underlying CKD. Patients who required ventilation had a significantly worse 90-day survival than those who did not (OR 2.10 for death; 95% CI 1.34, 3.29) whereas underlying CKD did not predict such an early adverse outcome (OR 1.49; 95% CI 0.89, 2.50). By 5 years, patients who had been ventilated during the acute illness were no longer at increased risk (OR 0.79; 95% CI 0.38, 1.62) whereas the adverse effect of underlying CKD was statistically significant (OR 6.05; 95% CI 2.23, 16.5). Underlying CKD was also a strong predictor of the need for RRT during follow-up. CONCLUSION In an unselected series of patients with AKI requiring RRT, underlying CKD rather than illness severity predicted medium- to long-term mortality.

Post-transplant lymphoproliferative disorder: case report and review of susceptibility to EBV in the Scottish adult renal transplant pool

We report a case of high-grade non-Hodgkins lymphoma following Epstein-Barr virus (EBV) infection in a 38-year-old renal transplant recipient who was successfully treated with rituximab and remains alive 6 years later with reasonable graft function. We subsequently undertook a survey showing that 1.8% of the Scottish adult transplant pool are susceptible to EBV infection. Though a vaccine for EBV is currently not yet available, routine screening of potential renal transplant recipients for EBV should help identify those at increased risk of post-transplant lymhoproliferative disorder (PTLD), while tailoring of immunosuppression and antiviral prophylaxis with Ganciclovir may help reduce the emergence of this potentially life-threatening disease.