Vitamin A is not associated with exacerbations in multiple sclerosis

Background Vitamin A is a multifunctional vitamin that can inhibit the formation of Th17 cells, which are probably involved in the development of relapses in MS. Furthermore, it promotes Treg formation. Therefore, vitamin A can be hypothesized to be lower in patients than in healthy controls, and to decrease relapse risk in relapsing-remitting MS (RRMS) patients. Objective To compare vitamin A levels in MS patients and controls, and to investigate whether vitamin A levels are associated with relapse risk. Methods In a case-control study all-trans-retinol levels were compared between 31 RRMS patients and 29 matched controls. In a prospective longitudinal study in 73 RRMS patients, serum samples for all-trans-retinol measurements were taken every eight weeks. Associations between all-trans-retinol concentrations and relapse rates were calculated using Poisson regression with the individual serum levels as time-dependent variable. Associations between vitamin A and vitamin D were calculated. Results Mean vitamin A levels were lower in patients (2.16 μmol/l) than in controls (2.44 μmol/l) but with borderline significance (p=0.05). In the longitudinal study, during follow-up (mean 1.7 years), 58 patients experienced a total of 139 relapses. Monthly moving averages of all-trans retinol levels were categorized into tertiles: a low (3.7 μmol/l). Relapse rates were not associated with serum all-trans retinol levels (p>0.2), in univariate nor in multivariate analysis. Serum concentrations of all-trans-retinol and 25-OH-vitamin D were positively correlated, although this correlation was weak (r=0.15). Conclusion We did not find evidence for a role for vitamin A in the disease course of RRMS. We did find an association between vitamin A and D levels in the RRMS patients, possibly explained by dietary products that contain both fat-soluble vitamins

The impact of estimated glomerular filtration rate equations on chronic kidney disease staging in pediatric renal or heart transplant recipients

Background: The aim of this study was to evaluate the performance of selected pediatric estimated glomerular filtration rate (eGFR) equations in relation to the clinical management of children after renal or heart transplantation or post-chemotherapy treatment. Methods: This study was a retrospective cross-sectional analysis of 61 children whose glomerular function (GFR) had been determined using a single-dose inulin clearance (iGFR) method. Eight equations for estimating the GFR were evaluated for bias, agreement, accuracy, and clinical stratification. Results: The outcome of all eight eGFR equations differed from the value determined using the iGFR method, with the mean bias ranging from −3.4 to 20.7 ml/min/1.73 m2 and 90 % accuracy ranging from 16 to 26 %. All eGFR equations overestimated renal function in patients with decreased kidney function as determined by the iGFR method and underestimated renal function in patients with normal kidney function. Consequently, based on the eGFR values, patients with low GFR values according to the iGFR method were staged in a less severe chronic kidney disease (CKD) category, and patients with normal GFR values according to the iGFR method were staged in a more severe CKD category. The percentage of correctly classified patients ranged from 32.6 to 41.6 %. Conclusions: In our cohort we found the CKiDIII equation to be the best alternative to calculating the GFR using the inulin clearance method, closely followed by the Hoste and the revised Grubb equations. The performances of all eight eGFR equations assessed were moderate at best and only slightly better than the easy-to-do bedside Schwartz equation

Diagnostic value of urinary dysmorphic erythrocytes in clinical practice

Background: In clinical practice, discriminating between glomerular and nonglomerular causes of hematuria is often difficult. Dysmorphic red blood cells (dRBC) in the urinary sediment are claimed to be effective, but the cutoff points in the literature vary. This follow-up study aimed to determine the diagnostic value of dRBC. Methods: We investigated 134 hematuria patients in the departments of nephrology and urology. To diagnose the origin of hematuria, urological and/or nephrological examination was performed and the %dRBC identified by microscopy. Follow-up was performed after 3.5 years. Results: The cause of hematuria was proven in 68 patients (35% glomerular; 65% nonglomerular). Patients with glomerular disease had significantly more albuminuria and dRBC than patients with nonglomerular disease, but the %dRBC ranged from 1 to 50% and no optimal cutoff could be identified. Logistic regression analysis showed that %dRBC had a predicted probability to diagnose glomerular disease of 77.9% (area under the curve, AUC, 0.85). When %dRBC was combined with other risk factors such as serum creatinine, sex, age, dipstick erythrocyte or proteinuria score and number of casts, the predictive probability increased to 90.6% (AUC 0.97). Follow-up of the included patients showed no benefit of dRBC to identify patients at risk for glomerular disease. Conclusions: The diagnostic value of routinely collected urinary dRBC to diagnose glomerular disease in patients presenting with hematuria is modest. However, including dRBC with other variables, such as age and erythrocyte score on dipstick testing may increase the sensitivity, but needs to be confirmed in another, preferably larger, population. Copyrigh