Capacity for the management of kidney failure in the International Society of Nephrology Africa region: report from the 2023 ISN Global Kidney Atlas (ISN-GKHA).

The burden of chronic kidney disease and associated risk of kidney failure are increasing in Africa. The management of people with chronic kidney disease is fraught with numerous challenges because of limitations in health systems and infrastructures for care delivery. From the third iteration of the International Society of Nephrology Global Kidney Health Atlas, we describe the status of kidney care in the ISN Africa region using the World Health Organization building blocks for health systems. We identified limited government health spending, which in turn led to increased out-of-pocket costs for people with kidney disease at the point of service delivery. The health care workforce across Africa was suboptimal and further challenged by the exodus of trained health care workers out of the continent. Medical products, technologies, and services for the management of people with nondialysis chronic kidney disease and for kidney replacement therapy were scarce due to limitations in health infrastructure, which was inequitably distributed. There were few kidney registries and advocacy groups championing kidney disease management in Africa compared with the rest of the world. Strategies for ensuring improved kidney care in Africa include focusing on chronic kidney disease prevention and early detection, improving the effectiveness of the available health care workforce (e.g., multidisciplinary teams, task substitution, and telemedicine), augmenting kidney care financing, providing quality, up-to-date health information data, and improving the accessibility, affordability, and delivery of quality treatment (kidney replacement therapy or conservative kidney management) for all people living with kidney failure.

An update on the global disparities in kidney disease burden and care across world countries and regions.

BACKGROUND: Since 2015, the International Society of Nephrology (ISN) Global Kidney Health Atlas (ISN-GKHA) has spearheaded multinational efforts to understand the status and capacity of countries to provide optimal kidney care, particularly in low-resource settings. In this iteration of the ISN-GKHA, we sought to extend previous findings by assessing availability, accessibility, quality, and affordability of medicines, kidney replacement therapy (KRT), and conservative kidney management (CKM). METHODS: A consistent approach was used to obtain country-level data on kidney care capacity during three phases of data collection in 2016, 2018, and 2022. The current report includes a detailed literature review of published reports, databases, and registries to obtain information on the burden of chronic kidney disease and estimate the incidence and prevalence of treated kidney failure. Findings were triangulated with data from a multinational survey of opinion leaders based on the WHO's building blocks for health systems (ie, health financing, service delivery, access to essential medicines and health technology, health information systems, workforce, and governance). Country-level data were stratified by the ISN geographical regions and World Bank income groups and reported as counts and percentages, with global, regional, and income level estimates presented as medians with interquartile ranges. FINDINGS: The literature review used information on prevalence of chronic kidney disease from 161 countries. The global median prevalence of chronic kidney disease was 9·5% (IQR 5·9-11·7) with the highest prevalence in Eastern and Central Europe (12·8%, 11·9-14·1). For the survey analysis, responses received covered 167 (87%) of 191 countries, representing 97·4% (7·700 billion of 7·903 billion) of the world population. Chronic haemodialysis was available in 162 (98%) of 165 countries, chronic peritoneal dialysis in 130 (79%), and kidney transplantation in 116 (70%). However, 121 (74%) of 164 countries were able to provide KRT to more than 50% of people with kidney failure. Children did not have access to haemodialysis in 12 (19%) of 62 countries, peritoneal dialysis in three (6%) countries, or kidney transplantation in three (6%) countries. CKM (non-dialysis management of people with kidney failure chosen through shared decision making) was available in 87 (53%) of 165 countries. The annual median costs of KRT were: US$19 380 per person for haemodialysis, $18 959 for peritoneal dialysis, and $26 903 for the first year of kidney transplantation. Overall, 74 (45%) of 166 countries allocated public funding to provide free haemodialysis at the point of delivery; use of this funding scheme increased with country income level. The median global prevalence of nephrologists was 11·8 per million population (IQR 1·8-24·8) with an 80-fold difference between low-income and high-income countries. Differing degrees of health workforce shortages were reported across regions and country income levels. A quarter of countries had a national chronic kidney disease-specific strategy (41 [25%] of 162) and chronic kidney disease was recognised as a health priority in 78 (48%) of 162 countries. INTERPRETATION: This study provides new information about the global burden of kidney disease and its treatment. Countries in low-resource settings have substantially diminished capacity for kidney care delivery. These findings have major policy implications for achieving equitable access to kidney care. FUNDING: International Society of Nephrology.

COVID-19 and the kidney: A South African state healthcare experience.

The first documented case of SARS-CoV-2 infection was confirmed in South Africa (SA) in March 2020. The Western Cape (WC) province was the initial epicenter. The pandemic peaked in July 2020 when 76,851 cases were documented and 2,323 deaths reported. COVID-19 can have multisystem involvement. Acute kidney injury (AKI) is well-documented and associated with increased mortality. We report our experience as the pandemic evolved in the WC province, focusing on those patients with a SARS-CoV-2 positive test presenting with AKI. We also reviewed our chronic dialysis cohort and renal transplant recipients who tested positive to assess incidence and outcomes. All patients presenting to nephrology services at the four main public hospitals were included. Information regarding demographics, co-morbidities, medical care, laboratory data, and outcomes were recorded. There were 86 patients referred with AKI, 48 required dialysis, and 47 died. There were 52 patients admitted to the intensive care unit with AKI (37 received dialysis, 1 of whom survived). In those presenting with AKI, diabetes, obesity, hypertension, and HIV were the most common comorbidities. Of the 295 patients receiving chronic dialysis within our services, 31 tested positive for SARS-CoV-2, and 6 died. Of the 45 kidney transplant recipients who tested positive, 9 died. Only 3 required dialysis. In conclusion, we report a high rate of AKI and poor prognosis in those requiring kidney replacement therapy, a better prognosis than anticipated was found in our chronic dialysis cohort, and high numbers of admissions were required for renal transplant recipients.

Estimated glomerular filtration rate in children: adapting existing equations for a specific population.

BACKGROUND: Creatinine-based glomerular filtration rate (GFR)-estimating equations frequently do not perform well in populations that differ from the development populations in terms of mean GFR, age, pathology, ethnicity, and diet. After first evaluating the performance of existing equations, the aim of this study was to demonstrate the utility of an in-house modification of the equations to better fit a specific population. METHODS: Estimated GFR using 8 creatinine-based equations was first compared to 2-sample 51Cr-ethylenediaminetetra-acetic acid plasma clearance in non-cancer and cancer groups independently. The groups were then divided into development and validation sets. Using the development set data, the Microsoft® Excel SOLVER add-in was used to modify the parameters of 7 equations to better fit the data. Using the validation set data, the performance of the original and modified equations was compared. RESULTS: Two hundred fifty-six GFR measurements were performed in 160 children. GFR was overestimated in both groups (non-cancer 4.3-22.6 ml/min/1.73 m2, cancer 17.2-46.6 ml/min/1.73 m2). The root mean square error (RMSE) was 19.1-21.8 ml/min/1.73 m2 (non-cancer) and 18.6-20.8 ml/min/1.73 m2 (cancer). The P30 values were 49.1-73.0% (non-cancer) and 19.6-66.0% (cancer). Modifying the parameters of seven equations resulted in significant improvements in the P30 values in the non-cancer (65.0-85.0%) and cancer (79.6-87.8%) groups. CONCLUSIONS: Modifying the parameters of pediatric GFR estimating-equations using a simple Excel-based tool significantly improved their accuracy in both non-cancer and cancer populations. Graphical abstract.

Prevalence of chronic kidney disease and association with cardiovascular risk factors among teachers in Cape Town, South Africa.

Background: There is a need to determine the feasibility of conducting studies of chronic diseases among large cohorts of African patients. One aim of the South African feasibility study was to determine the prevalence of chronic kidney disease (CKD) and its association with cardiovascular disease (CVD) risk factors among school teachers. Methods: In a cross-sectional survey of 489 teachers we captured data on demographics, CVD risk factors, anthropometry and blood pressure. Serum glucose, creatinine, cholesterol and urine protein/creatinine ratio was measured. Glomerular filtration rate was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and the Modification of Diet in Renal Disease study equations. Results: The mean (± standard deviation) age of the participants was 46.3 ± 8.5 years, with 70.3% being female and 74.6% of mixed ethnicity. The crude prevalence of CKD using the CKD-EPI equation was 6.1% while the age-adjusted prevalence was 6.4% (95% confidence interval 3.2-9.7%). CKD was associated with the presence of diabetes and higher diastolic blood pressures. Conclusions: In our study population of relatively young, working individuals CKD was common, clinically silent and associated with cardiovascular risk factors. The long-term complications of CKD are serious and expensive to manage and this, therefore, constitutes an important public health problem for South Africa.

Strengthening Renal Registries and ESRD Research in Africa.

In Africa, the combination of noncommunicable diseases, infectious diseases, exposure to environmental toxins, and acute kidney injury related to trauma and childbirth are driving an epidemic of chronic kidney disease and end-stage renal disease (ESRD). Good registry data can inform the planning of renal services and can be used to argue for better resource allocation, audit the delivery and quality of care, and monitor the impact of interventions. Few African countries have established renal registries and most have failed owing to resource constraints. In this article we briefly review the burden of chronic kidney disease and ESRD in Africa, and then consider the research questions that could be addressed by renal registries. We describe examples of the impact of registry data and summarize the sparse primary literature on country-wide renal replacement therapy in African countries over the past 20 years. Finally, we highlight some initiatives and opportunities for strengthening research on ESRD and renal replacement therapy in Africa. These include the establishment of the African Renal Registry and the availability of new areas for research. We also discuss capacity building, collaboration, open-access publication, and the strengthening of local journals, all measures that may improve the quantity, visibility, and impact of African research outputs.

Quality of life in patients on chronic dialysis in South Africa: a comparative mixed methods study.

BACKGROUND: The increasing prevalence of treated end-stage renal disease and low transplant rates in Africa leads to longer durations on dialysis. Dialysis should not only be aimed at prolonging lives but also improve quality of life (QOL). Using mixed methods, we investigated the QOL of patients on chronic haemodialysis (HD) and peritoneal dialysis (PD). METHODS: We conducted a cross-sectional study at Tygerberg Hospital in Cape Town, South Africa. All the PD patients were being treated with continuous ambulatory peritoneal dialysis. The KDQOL-SF 1.3 questionnaire was used for the quantitative phase of the study. Thereafter, focus-group interviews were conducted by an experienced facilitator in groups of HD and PD patients. Electronic recordings were transcribed verbatim and analysed manually to identify emerging themes. RESULTS: A total of 106 patients completed questionnaires and 36 of them participated in the focus group interviews. There was no difference between PD and HD patients in the overall KDQOL-SF scores. PD patients scored lower with regard to symptoms (P = 0.005), energy/fatigue (P = 0.025) and sleep (P = 0.023) but scored higher for work status (P = 0.005) and dialysis staff encouragement (P = 0.019) than those on HD. Symptoms and complications were verbalised more in the PD patients, with fear of peritonitis keeping some housebound. PD patients were more limited by their treatment modality which impacted on body image, sexual function and social interaction but there were less dietary and occupational limitations. Patients on each modality acknowledged the support received from family and dialysis staff but highlighted the lack of support from government. PD patients had little opportunity for interaction with one another and therefore enjoyed less support from fellow patients. CONCLUSIONS: PD patients experienced a heavier symptom burden and greater limitations related to their dialysis modality, especially with regards to social functioning. The mixed-methods approach helped to identify several issues affecting quality of life which are amenable to intervention.

Gitelman syndrome in a South African family presenting with hypokalaemia and unusual food cravings.

BACKGROUND: Gitelman syndrome (GS) is an autosomal recessive renal tubular disorder characterised by renal salt wasting with hypokalaemia, metabolic alkalosis, hypomagnesaemia and hypocalciuria. It is caused by mutations in SLC12A3 encoding the sodium-chloride cotransporter on the apical membrane of the distal convoluted tubule. We report a South African family with five affected individuals presenting with hypokalaemia and unusual food cravings. METHODS: The affected individuals and two unaffected first degree relatives were enrolled into the study. Phenotypes were evaluated through history, physical examination and biochemical analysis of blood and urine. Mutation screening was performed by sequencing of SLC12A3, and determining the allele frequencies of the sequence variants found in this family in 117 ethnically matched controls. RESULTS: The index patient, her sister, father and two aunts had a history of severe salt cravings, fatigue and tetanic episodes, leading to consumption of large quantities of salt and vinegar. All affected individuals demonstrated hypokalaemia with renal potassium wasting. Genetic analysis revealed that the pseudo-dominant pattern of inheritance was due to compound heterozygosity with two novel mutations: a S546G substitution in exon 13, and insertion of AGCCCC at c.1930 in exon 16. These variants were present in the five affected individuals, but only one variant each in the unaffected family members. Neither variant was found in any of the controls. CONCLUSIONS: The diagnosis of GS was established in five members of a South African family through clinical assessment, biochemical analysis and mutation screening of the SLC12A3 gene, which identified two novel putative pathogenic mutations.

A renal registry for Africa: first steps.

There is a dearth of data on end-stage renal disease (ESRD) in Africa. Several national renal registries have been established but have not been sustainable because of resource limitations. The African Association of Nephrology (AFRAN) and the African Paediatric Nephrology Association (AFPNA) recognize the importance of good registry data and plan to establish an African Renal Registry. This article reviews the elements needed for a successful renal registry and gives an overview of renal registries in developed and developing countries, with the emphasis on Africa. It then discusses the proposed African Renal Registry and the first steps towards its implementation. A registry requires a clear purpose, and agreement on inclusion and exclusion criteria, the dataset and the data dictionary. Ethical issues, data ownership and access, the dissemination of findings and funding must all be considered. Well-documented processes should guide data collection and ensure data quality. The ERA-EDTA Registry is the world's oldest renal registry. In Africa, registry data have been published mainly by North African countries, starting with Egypt and Tunisia in 1975. However, in recent years no African country has regularly reported national registry data. A shared renal registry would provide participating countries with a reliable technology platform and a common data dictionary to facilitate joint analyses and comparisons. In March 2015, AFRAN organized a registry workshop for African nephrologists and then took the decision to establish, for the first time, an African Renal Registry. In conclusion, African nephrologists have decided to establish a continental renal registry. This initiative could make a substantial impact on the practice of nephrology and the provision of services for adults and children with ESRD in many African countries.

The influence of storage time and temperature on the measurement of serum, plasma and urine osmolality.

BACKGROUND: Many clinical laboratories require that specimens for serum and urine osmolality determination be processed within 3 h of sampling or need to arrive at the laboratory on ice. This protocol is based on the World Health Organization report on sample storage and stability, but the recommendation lacks good supporting data. We studied the effect of storage temperature and time on osmolality measurements. METHODS: Blood and urine samples were obtained from 16 patients and 25 healthy volunteers. Baseline serum, plasma and urine osmolality measurements were performed within 30 min. Measurements were then made at 3, 6, 12, 24 and 36 h on samples stored at 4-8℃ and room temperature. We compared baseline values with subsequent measurements and used difference plots to illustrate changes in osmolality. RESULTS: At 4-8℃, serum and plasma osmolality were stable for up to 36 h. At room temperature, serum and plasma osmolality were very stable for up to 12 h. At 24 and 36 h, changes from baseline osmolality were statistically significant and exceeded the total allowable error of 1.5% but not the reference change value of 4.1%. Urine osmolality was extremely stable at room temperature with a mean change of less than 1 mosmol/kg at 36 h. CONCLUSIONS: Serum and plasma samples can be stored at room temperature for up to 36 h before measuring osmolality. Cooling samples to 4-8℃ may be useful when delays in measurement beyond 12 h are anticipated. Urine osmolality is extremely stable for up to 36 h at room temperature.

An audit of 24-hour creatinine clearance measurements at Tygerberg Hospital and comparison with prediction equations.

BACKGROUND: Internationally, clinical guidelines recommend the use of creatinine-based equations to estimate glomerular filtration rate (GFR) for assessment and follow-up of kidney disease. The routine use of 24-hour creatinine clearances (CrCl) is no longer advocated. OBJECTIVES: To examine the indications for requesting CrCl at Tygerberg Hospital, identify problems associated with the procedure, and evaluate the utility of the Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) equations with different levels of renal dysfunction in the ethnic groups of the Western Cape. METHODS: A clinical audit of CrCl was performed. The estimated GFR as predicted by the modified CG and MDRD formulae was compared with CrCl in 252 patients, representing three local ethnic groups. MDRD formulae with and without the correction factor for black ethnic group (MDRD-B) were evaluated. RESULTS: Problems with urine collection or data supplied were identified in one-third of CrCl requests, leading to unreliable results. The CG correlated best with CrCl in the group as a whole. The average absolute and percentage differences from CrCl in the different ethnic groups were as follows: coloured (mixed ethnicity) (N = 186) - CG 13.4 ml/min/1.73 m(2) (18%), MDRD 16.8 ml/min/1.73 m(2) (23%) and MDRD-B 27.9 ml/ min/1.73 m(2) (38%); black (N = 21) - CG 14.8 ml/min/1.73 m(2) (19%), MDRD 12.9 ml/min/1.73 m(2) (17%) and MDRD-B 25.1 ml/min/1.73 m(2) (33%); white (N = 45) CG 13.5 ml/min/1.73 m2 (19%), MDRD 15.3 ml/min/1.73 m(2) (21%) and MDRD-B 24.8 ml/min/1.73 m(2) (35%). Throughout the renal function levels (chronic kidney disease stages 1 - 5) CG correlated better with CrCl than MDRD. CONCLUSIONS: Possible reasons for poor correlations include a high prevalence of obesity, underweight and normal GFR in the study population. There is a need for further research, using a gold standard, into the accuracy of these prediction equations in our unique patient populations before firm recommendations can be made regarding their use. Until then CrCl will continue to be widely used. Greater efforts at patient and health care worker education are required to ensure proper collections.