Blood ceramides as novel markers for renal impairment in systemic lupus erythematosus.

BACKGROUND: Lupus nephritis (LN) is the most common organ manifestation in systemic lupus erythematosus (SLE) and associated with a poor prognosis. Still, a noninvasive but reliable method to diagnose LN has not been established. Thus, we evaluated whether blood sphingolipids could serve as valid biomarkers for renal injury. METHODS: In this cross-sectional study, 82 participants were divided into three groups: 36 healthy controls and 17 SLE patients without renal injury (both: estimated glomerular filtration rate (eGFR) ≥ 80 ml/min/1.73 m2 and albumin/creatinine ≤ 30 mg/g) and 29  LN patients. LN patients were identified by renal biopsies and impaired renal function (eGFR < 80 ml/min/1.73 m2 and albumin/creatinine ratio > 30 mg/g). Venous blood was collected from all participants and sphingolipid levels in plasma and serum were measured by LC-MS/MS. RESULTS: Most interesting, concentrations of some specific ceramides, C16ceramide (Cer), C18Cer, C20Cer and C24:1Cer, were elevated in both, plasma and serum samples of patients suffering from biopsy-proven LN and impaired renal function, compared to healthy controls as well as SLE patients without renal injury. C24:1dhCer levels were elevated in plasma and serum samples from LN patients compared to SLE patients. Sphingosine levels were higher in plasma and serum of LN patients compared to healthy controls, but not compared to SLE patients. Sphinganine concentrations were significantly elevated in serum samples from LN patients compared to healthy controls and SLE. S1P and SA1P levels were higher in plasma samples of SLE and LN patients compared to healthy controls. Subsequent ROC analyses of plasma and serum data of the most altered ceramide species (C16Cer, C18Cer, C20Cer, C24:1Cer) between LN patients and SLE patients display a high diagnostic differentiation with significant AUCs especially for C24:1Cer serum levels. Further, C24:1Cer serum levels were not affected by glucocorticoid treatment and did not correlate with other renal markers, such as serum creatinine, eGFR and albumin/creatinine ratio. CONCLUSION: Our data reveal that chain-length specific ceramides in blood, most likely C24:1Cer levels in serum, could act as potent biomarkers for renal impairment in patients suffering from SLE.

Increasing quality and quantity of student placements in smaller rural health services: It can be done.

PROBLEM: Future rural nursing and midwifery workforce shortage and current shortage of placements for undergraduate nursing and midwifery students. DESIGN: Developmental evaluation. SETTING: Five small hospitals and a regional community health service. KEY MEASURES OF IMPROVEMENT: Increased number of placements available for students; sustainable, quality clinical placement system in place for the future. STRATEGIES FOR CHANGE: Clinical facilitators developed a clinical facilitation model and resources that increased quality and quantity of student placements, assisted clinicians to provide higher quality teaching to students, enabled students to develop skills in rural health care service provision and enhanced knowledge around future career options. EFFECTS OF CHANGE: Placement targets were met and all health services involved chose to continue the model of clinical facilitation developed after project funding ceased. The clinical education skills developed by staff under the project remain in the region to support future students. LESSONS LEARNT: It is possible to create a sustainable, high-quality, rural placement experience for larger numbers of nursing and midwifery students. Funding sources are available to continue the clinical facilitation model in to the future, but for it to work optimally, a steady supply of students across the year is required.

CXCL16 is expressed in podocytes and acts as a scavenger receptor for oxidized low-density lipoprotein.

Podocytes are a crucial cell type in the kidney and play an important role in the pathology of glomerular kidney diseases like membranous nephropathy (MN). The identification of new factors involved in the progression of glomerular kidney diseases is of great importance to the development of new strategies for the treatment of renal injury. Here we demonstrate that CXCL16 and ADAM10 are constitutively expressed in human podocytes in normal renal tissue. Proinflammatory cytokines like interferon-gamma and tumor necrosis factor-alpha induced the expression of cellular CXCL16 and the release of its soluble form from human podocytes. Using different metalloproteinase inhibitors, we provide evidence that ADAM10 is involved in the interferon-gamma- and tumor necrosis factor-alpha-induced shedding of CXCL16 from human podocytes. In addition, ADAM10 knockdown by siRNA significantly increased both CXCL16 levels and, surprisingly, its ADAM17-mediated release. Notably, targeting of CXCL16 in human podocytes both decreased the chemotaxis of CXCR6-expressing T cells and strongly reduced oxidized low-density lipoprotein uptake in human podocytes. Importantly, in kidney biopsies of patients with MN, increased glomerular CXCL16 expression was accompanied by high levels of oxidized low-density lipoprotein and decreased expression of ADAM10. In addition, we found increased glomerular ADAM17 expression in patients diagnosed with MN. In summary, we presume important roles for CXCL16, ADAM10, and ADAM17 in the development of MN, suggesting these proteins as new therapeutic targets in this glomerular kidney disease.

Multicenter study on the diagnostic value of a new RIA for the detection of free plasma metanephrines in the work-up for pheochromocytoma.

Available laboratory test methods for the detection of elevated concentrations of catecholamines and their metabolites in urine and/or plasma are not always sensitive enough for the detection of pheochromocytoma. High-quality immunoassays for these compounds appear to be as accurate as high-pressure liquid chromatography (HPLC) or gas chromatography/mass spectrometry (GC-MS). Therefore, the current project aims to establish a new sensitive radioimmunoassay (RIA) for the measurement of free metanephrines in the plasma of patients in the work-up for pheochromocytoma. We report first results of an ongoing multicenter clinico-chemical evaluation study in hypertensive patients and normotensive volunteers. After an overnight fast plasma samples were collected on ice in EDTA- and heparin-coated tubes after insertion of an indwelling venous line and resting in the supine (patients) or sitting position (normal volunteers) for 30 min. Plasma metanephrines were measured by a newly developed RIA from IBL, Hamburg, Germany. Good agreement of the assay with the tandem mass spectrometry (LC-MS/MS) method for normetanephrine (r2=0.975) and for metanephrine (r2=0.985) could be demonstrated. Both specimens, EDTA and heparin plasma, can be used with the same results. The RIA has a good precision of <15% in the normal range and of <10% in the elevated concentration range. Our preliminary data suggest a high validity of the newly developed RIA for measuring free metanephrine and normetanephrine in hypertensive subjects in both EDTA and heparin plasma. Further work is required to determine the accuracy of the test in larger patient populations and in patients with pheochromocytoma.

Resistant hypertension? Assessment of adherence by toxicological urine analysis.

OBJECTIVE: Uncontrolled hypertension under antihypertensive multidrug regimen is not necessarily always true resistance. Incomplete adherence is one of several possible causes of uncontrolled hypertension. Nonadherence remains largely unrecognized and is falsely interpreted as treatment resistance, as it is difficult to confirm or exclude objectively. This is the first study assessing adherence in patients with apparent resistant hypertension systematically via toxicological urine screening. METHODS: All patients referred from primary care physicians because of uncontrolled hypertension between 2004 and 2011 were analysed. Adherence was assessed in all patients with uncontrolled hypertension despite the concurrent use of at least four antihypertensive agents by using liquid chromatography-mass spectrometry analysis for antihypertensive drugs or their corresponding metabolites in urine. RESULTS: A total of 375 patients with uncontrolled hypertension were referred. After optimization of drug therapy and exclusion of white coat hypertension, 108 patients met criteria for resistant hypertension. Of those, 15 patients had secondary causes of hypertension and 17 achieved goal blood pressure with quadruple antihypertensive therapy. Of the remaining 76 patients, 40 patients (53%) were found to be nonadherent. Among nonadherent patients, 30% had complete and 70% had incomplete adherence; 85% of the latter had taken less than 50% of drugs prescribed. Lack of adherence was almost evenly distributed between different classes of antihypertensive drugs. CONCLUSION: Low adherence was the most common cause of poor blood pressure control in patients with apparent resistant hypertension, being twice as frequent as secondary causes of hypertension. Incomplete adherence was far more common than complete nonadherence; thus, assessment of adherence in patients on multiple drug regime is only reliable when all drugs are included in assessment. Assessing adherence by toxicological urine screening is a useful tool in detecting low adherence, especially in the setting of multidrug regimen as a cause of apparently resistant hypertension.