Background: The burden of kidney diseases is reported to be higher in lower- and middle-income countries as compared to developed countries, and countries in sub-Saharan Africa are reported to be most affected. Health systems in most sub-Sahara African countries have limited capacity in the form of trained and skilled health care providers, diagnostic support, equipment and policies to provide nephrology services. Several initiatives have been implemented to support establishment of these services. Methods: This is a situation analysis to examine the nephrology services in Tanzania. It was conducted by interviewing key personnel in institutions providing nephrology services aiming at describing available services and international collaborators supporting nephrology services. Results: Tanzania is a low-income country in Sub-Saharan Africa with a population of more than 55 million that has seen remarkable improvement in the provision of nephrology services and these include increase in the number of nephrologists to 14 in 2018 from one in 2006, increase in number of dialysis units from one unit (0.03 unit per million) before 2007 to 28 units (0.5 units per million) in 2018 and improved diagnostic services with introduction of nephropathology services. Government of Tanzania has been providing kidney transplantation services by funding referral of donor and recipients abroad and has now introduced local transplantation services in two hospitals. There have been strong international collaborators who have supported nephrology services and establishment of nephrology training in Tanzania. Conclusion: Tanzania has seen remarkable achievement in provision of nephrology services and provides an interesting model to be used in supporting nephrology services in low income countries.
2 November 2018 in IEEE Transactions on Biomedical Engineering
Objective: Chronic kidney disease (CKD) is a serious medical condition characterized by gradual loss of kidney function. Early detection and diagnosis is mandatory for adequate therapy and prognostic improvement. Hence, in the current pilot study we explore the use of image registration methods for detecting renal morphologic changes in patients with CKD. Methods: Ten healthy volunteers and nine patients with presumed CKD underwent dynamic T1 weighted imaging without contrast agent. From real and simulated dynamic time series, kidney deformation fields were estimated using a poroelastic deformation model. From the deformation fields several quantitative parameters reflecting pressure gradients, and volumetric and shear deformations were computed. Eight of the patients also underwent a kidney biopsy as a gold standard. Results: We found that the absolute deformation, normalized volume changes, as well as pressure gradients correlated significantly with arteriosclerosis from biopsy assessments. Furthermore, our results indicate that current image registration methodologies are lacking sensitivity to recover mild changes in tissue stiffness. Conclusion: Image registration applied to dynamic time series correlated with structural renal changes and should be further explored as a tool for invasive measurements of arteriosclerosis. Significance: Under the assumption that the proposed framework can be further developed in terms of sensitivity and specificity, it can provide clinicians with a non-invasive tool of high spatial coverage available for characterization of arteriosclerosis and potentially other pathological changes observed in chronic kidney disease.
Background: High repeatability, accuracy, and precision for renal function measurements need to be achieved to establish renal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as a clinically useful diagnostic tool. Purpose: To investigate the repeatability, accuracy, and precision of DCE-MRI measured renal perfusion and glomerular filtration rate (GFR) using iohexol–GFR as the reference method. Material and Methods: Twenty healthy non-smoking volunteers underwent repeated DCE-MRI and an iohexol–GFR within a period of 10 days. Single-kidney (SK) MRI measurements of perfusion (blood flow, Fb) and filtration (GFR) were derived from parenchymal intensity time curves fitted to a two-compartment filtration model. The repeatability of the SK-MRI measurements was assessed using coefficient of variation (CV). Using iohexol–GFR as reference method, the accuracy of total MR–GFR was determined by mean difference (MD) and precision by limits of agreement (LoA). Results: SK-Fb (MR1, 345 ± 84; MR2, 371 ± 103 mL/100 mL/min) and SK–GFR (MR1, 52 ± 14; MR2, 54 ± 10 mL/min/1.73 m2) measurements achieved a repeatability (CV) in the range of 15–22%. With reference to iohexol–GFR, MR–GFR was determined with a low mean difference but high LoA (MR1, MD 1.5 mL/min/1.73 m2, LoA [−42, 45]; MR2, MD 6.1 mL/min/1.73 m2, LoA [−26, 38]). Eighty percent and 90% of MR–GFR measurements were determined within ± 30% of the iohexol–GFR for MR1 and MR2, respectively. Conclusion: Good repeatability of SK-MRI measurements and good agreement between MR–GFR and iohexol–GFR provide a high clinical potential of DCE-MRI for renal function assessment. A moderate precision in MR-derived estimates indicates that the method cannot yet be used in clinical routine.
Fabry disease (FD) is an X-linked inborn metabolic disorder due to partial or complete lysosomal α-galactosidase A deficiency. FD is characterized by progressive renal insufficiency and cardio- and cerebrovascular involvement. Restricted access on Gb3-independent tissue injury experimental models has limited the understanding of FD pathophysiology and delayed the development of new therapies. Accumulating glycosphingolipids, mainly Gb3 and lysoGb3, are Fabry specific markers used in clinical follow up. However, recent studies suggest there is a need for additional markers to monitor FD clinical course or response to treatment. We used a gla-knockout zebrafish (ZF) to investigate alternative biomarkers in Gb3-free-conditions. RNA sequencing was used to identify transcriptomic signatures in kidney tissues discriminating gla-mutant (M) from wild type (WT) ZF. Gene Ontology (GO) and KEGG pathways analysis showed upregulation of immune system activation and downregulation of oxidative phosphorylation pathways in kidneys from M ZF. In addition, upregulation of the Ca2+ signaling pathway was also detectable in M ZF kidneys. Importantly, disruption of mitochondrial and lysosome-related pathways observed in M ZF was validated by immunohistochemistry. Thus, this ZF model expands the pathophysiological understanding of FD, the Gb3-independent effects of gla mutations could be used to explore new therapeutic targets for FD.
To the Editor: The concentration of the N-terminal prohormone of brain natriuretic peptide (NT-proBNP)1 is often increased in patients with a reduced renal function. The suggested diagnostic cutoffs in acute or subacute heart failure [e.g., 300 pg/mL (66 pmol/L) and 125 pg/mL (27 pmol/L), respectively] are therefore probably not applicable for hemodialysis (HD) patients. A better approach may be to diagnose patients according to changes from their baseline NT-proBNP concentrations. The changes in patients who experience a clinical event can be compared with the reference change value (RCV), which is based on the analytical CV (CVa) and the within-person biological variation (CVi). The within-person variation describes the natural fluctuations in the concentrations of constituents in a stable situation. This study reports the CVa, CVi, between-person biological variation (CVb), RCV, and index of individuality (II) in HD patients and healthy individuals. The Regional Committee for Medical and Health Research Ethics approved the study. Informed written consent was obtained from 17 clinically stable patients who had been treated with HD at least twice weekly for ≥2 months. The patients …