An Approach to Optimise Therapeutic Vancomycin Dosage in a Haemodialysis Population

Haemodialysis patients are at risk of gram-positive bacteraemia and commonly require intravenous vancomycin. Intravenously administered vancomycin is primarily excreted by the kidney and exhibits complex pharmacokinetics in haemodialysis patients; achieving therapeutic levels can be challenging. An audit in our unit showed current practises of vancomycin administration resulted in a high proportion of sub-therapeutic levels. A new protocol was developed with fixed weight-based loading and subsequent dosing guided by pre-dialysis levels, target levels were 10-20mg/L. Its effectiveness was prospectively evaluated between 24th September 2012, and 8th February 2013. During this period 25 patients commenced vancomycin, 15 were included. In total, 112 vancomycin levels were taken, 94 (84%) were therapeutic, this was a significant improvement compared to previous practise (odds ratio 5.4, CI 3.1-9.4, p<0.0001). In conclusion, our study shows this protocol can consistently and reliably achieve therapeutic vancomycin levels.

Prediction of hospital mortality by changes in the estimated glomerular filtration rate (eGFR)

Deterioration of physiological or laboratory variables may provide important prognostic information. We have studied whether a change in estimated glomerular filtration rate (eGFR) value calculated using the (Modification of Diet in Renal Disease (MDRD) formula) over the hospital admission, would have predictive value. An analysis was performed on all emergency medical hospital episodes (N = 61964) admitted between 1 January 2002 and 31 December 2011. A stepwise logistic regression model examined the relationship between mortality and change in renal function from admission to discharge. The fully adjusted Odds Ratios (OR) for 5 classes of GFR deterioration showed a stepwise increased risk of 30-day death with OR's of 1.42 (95% CI: 1.20, 1.68), 1.59 (1.27, 1.99), 2.71 (2.24, 3.27), 5.56 (4.54, 6.81) and 11.9 (9.0, 15.6) respectively. The change in eGFR during a clinical episode, following an emergency medical admission, powerfully predicts the outcome.

Chronic kidney disease in the elderly; a silent epidemic

Chronic kidney disease has been shown to be associated with significant increases in mortality and morbidity even in early stages. Despite this it is rarely diagnosed, actively investigated or managed in the elderly. We set out to establish the prevalence of CKD and identify causative factors in a consecutive series of referrals to a geriatric medical clinic. We calculated glomerular filtration rates (GFR) for 101 patients attending a geriatric medical clinic using the Cockroft and Gault formula, and collected data on medications and relevant past medical history. Mild CKD (GFR <60ml/min) was present in 80% of the group. Only 10% of these patients had serum creatinine >130(mmol/L. hypertension was present in 50% and only 9% were diabetic. Almost one third were on inappropriate drugs or dosages; most commonly non-steroidal anti-inflammatory drugs (99%). Chronic kidney disease is extremely common in older people attending a geriatric medical clinic and carries significant risks. CKD will not be detected by serum creatinine alone in 90% of cases. Routine calculation of GFR should be used to provide a more accurate measure of renal impairment and allow earlier intervention, risk factor reduction and improve prescribing practices.

Adequacy targets can be met in anuric patients by automated peritoneal dialysis: baseline data from EAPOS

OBJECTIVE

Conventional continuous ambulatory peritoneal dialysis (CAPD) in patients without residual renal function and with high solute transport is associated with worse clinical outcomes. Automated peritoneal dialysis (APD) has the potential to improve both solute clearance and ultrafiltration in these circumstances, but its efficacy as a treatment modality is unknown. The European Automated Peritoneal Dialysis Outcomes Study (EAPOS) is a 2-year, prospective, European multicenter study designed to determine APD feasibility and clinical outcomes in anuric patients. The present article describes the baseline data for patients recruited into the study.

DESIGN

All PD patients treated in the participating centers were screened for inclusion criteria [urinary output < 100 mL/24 h, or residual renal function (RRF) < 1 mL/min, or both]. After enrollment, changes were made to the dialysis prescription to achieve a weekly creatinine clearance above 60 L per 1.73 m2 and an ultrafiltration rate above 750 mL in 24 hours.

SETTING

The study is being conducted in 26 dialysis centers in 13 European countries. BASELINE DATA COLLECTION: The information collected includes patient demographics, dialysis prescription, achieved weekly creatinine clearance, and 24-hour ultrafiltration (UF).

RESULTS

The study enrolled 177 anuric patients. Median dialysis duration before enrollment was 22.5 months (range: 0-285 months). Mean solute transport measured as the dialysate-to-plasma ratio of creatinine (D/P(Cr)) was 0.74 +/- 0.12. Patients received APD for a median of 9.0 hours overnight (range: 7-12 hours) using a median of 11.0 L of fluid (range: 6-28.75 L). Median daytime volume was 4.0 L (range: 0.0-9.0 L). Tidal dialysis was used in 26 patients, and icodextrin in 86 patients. At baseline, before treatment optimization, the weekly mean total creatinine clearance was 65.2 +/- 14.4 L/1.73 m2, with 105 patients (60%) achieving the target of more than 60 L/1.73 m2. At baseline, 81% of patients with high transport, 69% with high-average transport, and 40% with low-average transport met the target. At baseline, 70% of patients with a body surface area (BSA) below 1.7 m2, 60% with a BSA of 1.7-2.0 m2, and 56% with a BSA above 2.0 m2 achieved 60 L/1.73 m2 weekly. Median UF was 1090 mL/24 h, and 75% of patients achieved the UF target of more than 750 mL/24 h.

CONCLUSION

This baseline analysis of anuric patients recruited into the EAPOS study demonstrates that a high proportion of anuric patients on APD can achieve dialysis and ultrafiltration targets using a variety of regimes. This 2-year follow-up study aims to optimize APD prescription to reach predefined clearance and ultrafiltration targets, and to observe the resulting clinical outcomes.

Haemolytic uraemic syndrome with shigella

A 49-year-old male developed bloody diarrhoea whilst on a visit to India. Sigmoidoscopy and rectal biopsy showed acute colitis. Shigella dysentery type I was isolated from stool culture. Cytotoxin production by the organism was demonstrated. The patient developed acute renal failure, thrombocytopaenia and microangiopathic haemolytic anaemia. He required mechanical ventilation, haemodialysis, blood transfusion and antibiotic therapy and achieved a complete recovery. This is an unusual case of haemolytic uraemic syndrome complicating shigellosis in an adult.