In memoriam: Anthony Molyneux Meyers

Professor Anthony Molyneux Meyers, a pioneer in nephrology in South Africa and a past president of the African Association of Nephrology, died on 24 September 2022 at the age of 89

Vasoactive peptides in acute renal allograft rejection and renal diseases: the role of endothelins, atrial natriuretic peptide and kinins.

Doctoral Degree. University of KwaZulu-Natal, Durban.Abstract available in PDF

Biochemical markers of mineral bone disorder in South African patients on maintenance haemodialysis

Background and objective: Despite the high mortality and morbidity associated with abnormalities in mineral and bone metabolism in haemodialysis patients, there is limited data on the pattern of mineral bone disorder in African CKD population. Therefore, the purpose of this study was to describe the pattern of mineral bone disease by evaluating biochemical parameters in patients on maintenance haemodialysis (MHD).Methods: We evaluated the serum/plasma intact parathyroid hormone (iPTH), corrected calcium, phosphate, total alkaline phosphatase (TALP) and 25 –OH vitamin D levels of two hundred and seven patients undergoing MHD at two dialysis centers in Johannesburg.Results: The MHD patients (133 men, 74 women) had a mean age of 54.5±15.6 years with a median dialysis vintage of 24 months (IQR, 12-48) and a mean kt/V of 1.45±0.28. The prevalence of hyperparathyroidism (iPTH >150 pg/ml), hyperphosphataemia, hypocalcaemia and 25-OH vitamin D deficiency (<30 ng/ml) was 73.4%, 57.0%, 20.3% and 80.7 % respectively. The combination of markers of bone turnover (iPTH >150pg/ml and TALP> 112 U/L) suggestive of high turnover bone disease, was present in 47.3 % of the study population. In multiple-logistic regression analysis, the odds ratio for developing hyperparathyroidism with hypocalcaemia and hyperphosphataemia were 5.32 (95% CI 1.10 - 25.9, P = 0.03) and 3.06(95 % CI 1.15 - 8.10, P=0.02) respectively. Ninety eight (47.3%) of the MHD patients had iPTH within the recommended kidney disease improving global outcome (KDIGO) guidelines.Conclusion: Secondary hyperparathyroidism and 25–OH vitamin D deficiency were common in our haemodialysis patients. Hypocalcaemia and hyperphosphataemia were strong predictors for developing secondary hyperparathyroidism.Keywords: Biochemical markers, guidelines, mineral bone disorder, haemodialysi

In memoriam: Rashad Sami Barsoum

Rashad Sami Barsoum, a pioneer in nephrology in Egypt and Africa, and former secretary general of the International Society of Nephrology and inaugural past president of the African Association of Nephrology, died on 25 October 2022, at the age of 81

Biochemical markers of mineral bone disorder in South African patients on maintenance haemodialysis.

Background and objective: Despite the high mortality and morbidity associated with abnormalities in mineral and bone metabolism in haemodialysis patients, there is limited data on the pattern of mineral bone disorder in African CKD population. Therefore, the purpose of this study was to describe the pattern of mineral bone disease by evaluating biochemical parameters in patients on maintenance haemodialysis (MHD). Methods: We evaluated the serum/plasma intact parathyroid hormone (iPTH), corrected calcium, phosphate, total alkaline phosphatase (TALP) and 25 \u2013OH vitamin D levels of two hundred and seven patients undergoing MHD at two dialysis centers in Johannesburg. Results: The MHD patients (133 men, 74 women) had a mean age of 54.5\ub115.6 years with a median dialysis vintage of 24 months (IQR, 12-48) and a mean kt/V of 1.45\ub10.28. The prevalence of hyperparathyroidism (iPTH >150 pg/ml), hyperphosphataemia, hypocalcaemia and 25-OH vitamin D deficiency (<30 ng/ml) was 73.4%, 57.0%, 20.3% and 80.7 % respectively. The combination of markers of bone turnover (iPTH >150pg/ml and TALP> 112 U/L) suggestive of high turnover bone disease, was present in 47.3 % of the study population. In multiple-logistic regression analysis, the odds ratio for developing hyperparathyroidism with hypocalcaemia and hyperphosphataemia were 5.32 (95% CI 1.10 - 25.9, P = 0.03) and 3.06(95 % CI 1.15 - 8.10, P=0.02) respectively. Ninety eight (47.3%) of the MHD patients had iPTH within the recommended kidney disease improving global outcome (KDIGO) guidelines. Conclusion: Secondary hyperparathyroidism and 25\u2013OH vitamin D deficiency were common in our haemodialysis patients. Hypocalcaemia and hyperphosphataemia were strong predictors for developing secondary hyperparathyroidism

High Serum Alkaline Phosphatase, Hypercalcaemia, Race, and Mortality in South African Maintenance Haemodialysis Patients

Objective. To determine the association between serum total alkaline phosphatase (TAP) and mortality in African maintenance haemodialysis patients (MHD). Patients and Methods. The study enrolled a total of 213 patients on MHD from two dialysis centers in Johannesburg between January 2009 and March 2016. Patients were categorized into a low TAP group (≤112 U/L) versus a high TAP group (>112 U/L) based on a median TAP of 112 U/L. Results. During the follow-up period of 7 years, there were 55 (25.8%) deaths. After adjusting for cofounders such as age, other markers of bone disorder, and comorbidity (diabetes mellitus), patients in the high TAP group had significantly higher risk of death compared to patients in the low TAP group (hazard ratio, 2.50; 95% CI 1.24-5.01, P = 0.01). Similarly, serum calcium >2.75 mmol/L was associated with increased risk of death compared to patients within levels of 2.10-2.37 mmol/L (HR 6.34, 95% CI 1.40-28.76; P = 0.02). The HR for death in white patients compared to black patients was 6.88; 95% CI 1.82-25.88; P = 0.004. Conclusion. High levels of serum alkaline phosphatase, hypercalcaemia, and white race are associated with increased risk of death in MHD patients

Cardiovascular disease in chronic kidney disease – a review of risk factors

Patients with chronic kidney disease (CKD) are at increased risk of cardiovascular disease (CVD), such that the risk of cardiovascular mortality is greater than the risk of progression to end-stage kidney disease. Despite the increased prevalence of traditional and non-traditional cardiovascular risk factors, patients with kidney disease have been mostly under-represented in previous cardiovascular outcome studies, thereby resulting in a paucity of data on the evidence-based management of CVD in CKD. In this review, we explore the evidence on the burden of CVD and its risk factors in patients with CKD, highlight various inflammatory biomarkers for predicting CVD and provide an overview on novel biomarkers for CVD

Reduced glomerular filtration rate is associated with ascending aortic dilatation in South African chronic kidney disease patients

Background: Ascending aortic dilatation (AAD) is an adverse prognostic cardiovascular marker in the general population. There are few data reporting its presence or clinical significance in chronic kidney disease (CKD) patients. The aim of this study was to evaluate ascending aorta dimensions and their correlates in a population of South African CKD patients.Methods: A total of 124 CKD patients and 40 healthy controls were enrolled. Cardiac dimensions, systolic and diastolic function indices, and aortic root diameters were assessed by transthoracic echocardiography. The ascending aorta was measured at four levels (aortic annulus, sinuses of Valsalva, sino-tubular junction, and ascending aorta) and was normalised for body surface area. The prevalence of AAD was assessed in CKD patients compared with the control group.Results: In CKD patients, the ascending aorta dimension was significantly larger than in controls at all four sites of the aorta that were measured. The prevalence of AAD was 6.5% at the annulus, 12.9% at the sinuses, 15.3% at the sino-tubular junction, and 8.9% at the ascending aorta. Overall, 29 patients (23%) had AAD. On multivariate analyses, eGFR was independently associated with AAD (odds ratio 0.980; 95% confidence interval 0.965–0.996; P = 0.014).Conclusion: AAD is a common cardiovascular phenotype in South African CKD patients. Low eGFR was independently associated with AAD, suggesting a direct link between CKD and the development of AAD in South African CKD patients

A cohort study of the relationship between anaemia, mean corpuscular volume and mortality among a CKD population in South Africa

Background: The burden of chronic kidney disease is increasing globally and prompt identification, coupled with improved management of CKD patients have increased the population of pre-dialysis patients. We, therefore, aimed to evaluate the predictors of survival among pre-dialysis CKD patients in South Africa. Methods: We conducted a cohort study of 256 consecutive consenting Black non-dialysis requiring CKD patients attending the renal outpatient clinic of a tertiary Hospital in South Africa from 1st June 2016 to 1st December 2016. Socio-demographic and clinical information of the participants were obtained. Descriptive statistics, Kaplan-Meier curves and Cox proportional hazard regression analyses were conducted to evaluate factors affecting the survival of the participants. Results: The mean age of the participants was 52.8±14.3 years and 48.0% were females, 52% were males. The death rate increased with worsening haemoglobin level from 0.96 among patients with mild anaemia to 4.29 per 100-person years among patients with severe anaemia. Anaemic patients with GFR < 30mls/min had significantly increased risk of death (HR 11.51, 95% CI 1.62–78.32, P < 0.001). Conclusion: Mortality in pre-dialysis CKD patients was associated with anaemia and hyperphosphatemia. Clinical interventions targeted at preventing these conditions may improve outcomes among this group of CKD patients. Keywords: Chronic kidney disease; mortality anaemia; outcomes, survival

The epidemiology of chronic kidney disease in sub-Saharan Africa: a systematic review and meta-analysis

Background Amid rapid urbanisation, the HIV epidemic, and increasing rates of non-communicable diseases, people in sub-Saharan Africa are especially vulnerable to kidney disease. Little is known about the epidemiology of chronic kidney disease (CKD) in sub-Saharan Africa, so we did a systematic review and meta-analysis examining the epidemiology of the disease. Methods We searched Medline, Embase, and WHO Global Health Library databases for all articles published through March 29, 2012, and searched the reference lists of retrieved articles. We independently reviewed each study for quality. We used the inverse-variance random-eff ects method for meta-analyses of the medium-quality and highquality data and explored heterogeneity by comparing CKD burdens across countries, settings (urban or rural), comorbid disorders (hypertension, diabetes, HIV), CKD defi nitions, and time. Findings Overall, we included 90 studies from 96 sites in the review. Study quality was low, with only 18 (20%) medium-quality studies and three (3%) high-quality studies. We noted moderate heterogeneity between the mediumquality and high-quality studies (n=21; I²=47·11%, p<0·0009). Measurement of urine protein was the most common method of determining the presence of kidney disease (62 [69%] studies), but the Cockcroft-Gault formula (22 [24%] studies) and Modifi cation of Diet in Renal Disease formula (17 [19%] studies) were also used. Most of the studies were done in urban settings (83 [93%] studies) and after the year 2000 (57 [63%] studies), and we detected no signifi cant diff erence in the prevalence of CKD between urban (12·4%, 95% CI 11–14) and rural (16·5%, 13·8–19·6) settings (p=0·474). The overall prevalence of CKD from the 21 medium-quality and high-quality studies was 13·9% (95% CI 12·2–15·7). Interpretation In sub-Saharan Africa, CKD is a substantial health burden with risk factors that include communicable and non-communicable diseases. However, poor data quality limits inferences and draws attention to the need for more information and validated measures of kidney function especially in the context of the growing burden of noncommunicable diseases