Gerhard Wirnsberger

The assessment of GFR after orthotopic liver transplantation using cystatin C and creatinine‐based equations

The measurement of kidney function after orthotopic liver transplantation (OLT) is still a clinical challenge. Cystatin C (CysC) has been proposed as a more accurate marker of renal function than serum creatinine (sCr). The aim of this study was to evaluate sCr‐ and CysC‐based equations including the Chronic kidney disease (CKD)‐EPI to determine renal function in liver transplant recipients. CysC and sCr were measured in 49 patients 24 months after OLT. The glomerular filtration rate (GFR) was calculated using the MDRD 4, the Cockroft‐Gault, Hoek, Larsson, and the CKD‐EPI equations based on sCr and/or CysC. As reference method, inulin clearance (IC) was estimated. Bias, precision, and accuracy of each equation were assessed and compared with respect to IC. Forty‐five percent had a GFR < 60 ml/min/1.73 m2 according to the IC. The Larsson, the Hoek and the CKD‐EPI‐CysC formula identified the highest percentage of patients with CKD correctly (88%, 88%, and 84%, respectively). The sCr‐based equations showed less bias than CysC‐based formulas with a similar precision. All CysC‐based equations were superior as compared with sCr‐based equations in the assessment of renal function in patients with an IC < 60 ml/min/1.73 m2.

The Graz Malnutrition Screening (GMS): a new hospital screening tool for malnutrition.

Despite the significant impact of malnutrition in hospitalised patients, it is often not identified by clinical staff in daily practice. To improve nutritional support in hospitals, standardised routine nutritional screening is essential. The Graz Malnutrition Screening (GMS) tool was developed for the purpose of malnutrition risk screening in a large hospital setting involving different departments. It was the aim of the present study to validate the GMS against Nutritional Risk Screening (NRS) and Mini Nutritional Assessment-short form (MNA-sf) in a randomised blinded manner. A total of 404 randomly selected patients admitted to the internal, surgical and orthopaedic wards of the University Hospital Graz were screened in a blinded manner by different raters. Concurrent validity was determined by comparing the GMS with the NRS and in older patients (70+ years) with the MNA-sf additionally. According to GMS, 31·9 or 28·5 % of the admitted patients were categorised as at ‘risk of malnutrition’ (depending on the rater). According to the reference standard of NRS, 24·5 % of the patients suffered from malnutrition. Pearson’s r values of 0·78 compared with the NRS and 0·84 compared with the MNA showed strong positive correlations. Results of accuracy (0·85), sensitivity (0·94), specificity (0·77), positive predictive value (0·76) and negative predictive value (0·95) of GMS were also very high. Cohen’s κ for internal consistency of the GMS was 0·82. GMS proves to be a valid and reliable instrument for the detection of malnutrition in adult patients in acute-care hospitals.

Outcomes in patients with chronic kidney disease not on dialysis receiving extended dosing regimens of darbepoetin alfa: long-term results of the EXTEND observational cohort study

Background Extended dosing of the erythropoiesis-stimulating agent (ESA) darbepoetin alfa (DA) once biweekly or monthly reduces anaemia treatment burden. This observational study assessed outcomes and dosing patterns in patients with chronic kidney disease not on dialysis (CKD-NoD) commencing extended dosing of DA. Methods Adult CKD-NoD patients starting extended dosing of DA in Europe or Australia in June 2006 or later were followed up until December 2012. Outcomes included haemoglobin (Hb) concentration, ESA dosing, mortality rates and receipt of dialysis and renal transplantation. Subgroup analyses were conducted for selected outcomes. Results Of 6035 enrolled subjects, 5723 (94.8%) met analysis criteria; 1795 (29.7%) received dialysis and 238 (3.9%) underwent renal transplantation. Mean (standard deviation) Hb concentration at commencement of extended dosing was 11.0 (1.5) g/dL. Mean [95% confidence interval (CI)] Hb 12 months after commencement of extended dosing (primary outcome) was 11.6 g/dL (11.5, 11.6) overall and was similar across countries, with no differences between subjects previously treated with an ESA versus ESA-naïve subjects, subjects with versus without prior renal transplant or diabetics versus non-diabetics. Weekly ESA dose gradually decreased following commencement of extended DA dosing and was similar across subgroups. The decrease in weekly DA dose was accompanied by an increase in the proportion of patients receiving iron therapy. Hb concentrations declined following changes in ESA labels and treatment guidelines. The mortality rate (95% CI) was 7.06 (6.68, 7.46) deaths per 100 years of follow-up. Subjects alive at study end had stable Hb concentrations in the preceding year, while those who died had lower and declining Hb concentrations in their last year. Conclusions Long-term, extended dosing of DA maintained Hb concentrations in patients already treated with an ESA and corrected and maintained Hb in ESA-naïve patients.

Kidney Disease in Old Age

In older people important causes of chronic kidney diseases (CKD) are diabetes and hypertension, which are responsible for up to two-thirds of the cases. Other risk factors are urinary infections, abuse of pain relieving medications (NSAIDs), different types of primary glomerulonephritis, and some inherited disease. An acute renal failure (ARF) is common caused by an event that leads to a sudden kidney malfunction, such as dehydration, nephrotoxic medicines, e.g., NSAIDs and contrast agents, or postrenal obstruction. Kidney sonography may help to determine whether kidney problems are acute or chronic. The treatment of acute kidney injury includes correcting the cause and supporting the kidneys with fluid. Only in some cases dialysis is indicated when severe hyperkalemia, metabolic acidosis, or volume overload cannot be managed. Progression to end-stage renal disease (ESRD) is typically characterized by the loss of a number ofbiological functions, including fluid and electrolyte balance, and endocrine, neurological, hematological, and cardiovascular dysfunctions. Elderly patients often develop complications like anemia, poor nutritional health, and nerve damage very early. Disturbances in calcium homeostasis chronic also increase the risk of an arterial and systemic calcifications. For these reasons, identification and management of CKD patients are of paramount importance to implement interventions aimed at slowing the progression of kidney disease and delaying the onset of its complications.

Disorders of Fluid Balance

Characteristic of the normal aging process is a decline in physiologic reserve in many body regulatory systems, including those involved in the maintenance of fluid balance. Clinicians who are involved in the care of the older person recognize that disturbances of water and electrolyte balance are common in this age group, especially when older persons are challenged by disease, drugs, or extrinsic factors such as access to fluids or control of diet composition.

Estimated glomerular filtration rate and functional status among older people : A systematic review.

BACKGROUND The association between chronic kidney disease (CKD) and functional status may change as a function of the equation used to estimate glomerular filtration rate (eGFR). We reviewed the predictive value of different eGFR equations in regard to frailty and disability outcomes. METHODS We searched Pubmed from inception to March 2018 for studies investigating the association between eGFR and self-reported and/or objective measures of frailty or disability. Cross-sectional and longitudinal studies were separately analysed. RESULTS We included 16 studies, one of which reporting both cross-sectional and longitudinal data. Three out of 7 cross-sectional studies compared different eGFR equations in regard to their association with functional status: two studies showed that cystatin C-based, but not creatinine-based eGFR may be associated with hand-grip strength or frailty; another study showed that two different creatinine-based eGFR equations may be similarly associated with disability. Four out of 10 longitudinal studies provided comparative data: two studies reported similar association with disability for different creatinine-based eGFR equations; one study showed that creatinine-based eGFR was not associated with frailty, but a not significant trend for association was observed with cystatin C-based eGFR; one study showed that cystatin C-based but not creatinine-based eGFR may predict incident mobility disability, while both methods may predict gait speed decline. High heterogeneity was observed in regard to confounders included in reviewed studies. None of them included the most recently published equations. CONCLUSION Available data do not support the superiority of one of the eGFR equations in terms of measuring or predicting functional decline.

Psychometric testing of the "Graz Malnutrition Screening Tool" (GMS) - Validity, Reliability, Sensitivity & Specificity

Background Despite high prevalence rates of malnutrition in hospitals, awareness of medical and nursing staff is still rather low [1]. The implementation of valid malnutrition screening tools within preexisting electronic data source systems seems mandatory. Hospitals are in need of an easy to handle, valid and reliable malnutrition screening tool with high sensitivity and specificity for all kind of adult patient groups. The GMS was developed by a multidisciplinary nutrition team of the University Hospital Graz (Austria). It is primarily based on the ESPEN recommendations [2] and consists of five items shown in table 1. To individualize for special needs of older patients, age was introduced as independent risk factor.