No abstract

BackgroundPopulation-based data on the burden of chronic kidney disease (CKD) in sub-Saharan Africa is still very limited. We assessed the prevalence and determinants of CKD, and evaluated the concordance of commonly advocated estimators of glomerular filtration rate (eGFR) in a mixed ancestry population from South Africa.MethodsParticipants were a population-based sample of adults selected from the Bellville-South community in the metropolitan city of Cape Town. eGFR was based on the Cockroft-Gault (CG), Modification of Diet in Kidney Disease (MDRD) and CKD Epidemiology Collaboration (CKD-EPI) equations (with and without adjustment for ethnicity). Kidney function staging used the Kidney Disease Outcome Quality Initiative (KDOQI) classification. Logistic regressions and kappa statistic were used to investigate determinants of CKD and assess the agreement between different estimators.ResultsThe crude prevalence of CKD stage 3–5 was 14.8% for Cockcroft-Gault, 7.6% and 23.9% respectively for the MDRD with and without ethnicity correction, and 7.4% and 17.3% for the CKD-EPI equations with and without ethnicity correction. The highest agreement between GFR estimators was between MDRD and CKD-EPI equations, both with ethnicity correction, Kappa 0.91 (95% CI: 0.86-0.95), correlation coefficient 0.95 (95% CI: 0.94-0.96). In multivariable logistic regression models, sex, age and known hypertension were consistently associated with CKD stage 3–5 across the 5 estimators.ConclusionsThe prevalence of CKD stages greater than 3 is the highest reported in Africa. This study provides evidence for support of the CKD-EPI equation for eGFR reporting and CKD classification.

Background: Hyperkalemia is a common medical emergency that may result in serious cardiac arrhythmias. Standard therapy with insulin plus glucose reliably lowers the serum potassium concentration ([K⁺]) but carries the risk of hypoglycemia. This study examined whether an intravenous glucose-only bolus lowers serum [K⁺] in stable, nondiabetic, hyperkalemic patients and compared this intervention with insulin-plus-glucose therapy. Methods: A randomized, crossover study was conducted in 10 chronic hemodialysis patients who were prone to hyperkalemia. Administration of 10 units of insulin with 100 ml of 50% glucose (50 g) was compared with the administration of 100 ml of 50% glucose only. Serum [K⁺] was measured up to 60 min. Patients were monitored for hypoglycemia and EKG changes. Results: Baseline serum [K⁺] was 6.01 ± 0.87 and 6.23 ± 1.20 mmol/l in the insulin and glucose-only groups, respectively (p = 0.45). At 60 min, the glucose-only group had a fall in [K⁺] of 0.50 ± 0.31 mmol/l (p < 0.001). In the insulin group, there was a fall of 0.83 ± 0.53 mmol/l at 60 min (p < 0.001) and a lower serum [K⁺] at that time compared to the glucose-only group (5.18 ± 0.76 vs. 5.73 ± 1.12 mmol/l, respectively; p = 0.01). In the glucose-only group, the glucose area under the curve (AUC) was greater and the insulin AUC was smaller. Two patients in the insulin group developed hypoglycemia. Conclusion: Infusion of a glucose-only bolus caused a clinically significant decrease in serum [K⁺] without any episodes of hypoglycemia.

No abstract

Iron is a vital element in the multifactorial initiation of myelination. It is required for cholesterol and lipid biosynthesis, both key components of myelin. Iron also plays an important role in energy production by mitochondrial oxidative metabolism which occurs in myelin-producing oligodentrocytes at a higher rate than in any other cell. Iron deficiency can, therefore, result in decreased oligodendrocyte survival and defective myelination. This led us to investigate iron status in 2 consecutive children with multiple sclerosis who presented with recurrent episodes of tumefactive demyelination. Testing revealed nonanemic iron deficiency in both patients. Discontinuation of iron supplementation in both children resulted in recurrent decreased iron parameters which can indicate mutations in proteins responsible for regulation of iron uptake. Further studies are warranted to explore the association of low iron in children presenting with recurrent episodes of tumefactive demyelination.

This open-access article is distributed under Creative Commons licence CC-BY-NC 4.0.

This study demonstrated that free light chain concentrations were significantly correlated with markers of HIV disease severity, suggesting ongoing B cell dysfunction despite ART use. Free light chain ratio was not significantly affected.

Our audit highlights the potential errors during the post-analytical phase of laboratory testing. The importance of critical result reporting is still poorly recognized in South Africa. Implementation of a uniform accredited practice for communication of critical results can reduce error and improve patient safety.