Chronic kidney disease in sub-Saharan Africa: a public health priority

The Effect of ß-Glucan Prebiotic on Kidney Function, Uremic Toxins and Gut Microbiome in Stage 3 to 5 Chronic Kidney Disease (CKD) Predialysis Participants: A Randomized Controlled Trial

There is growing evidence that gut dysbiosis contributes to the progression of chronic kidney disease (CKD) owing to several mechanisms, including microbiota-derived uremic toxins, diet and immune-mediated factors. The aim of this study was to investigate the effect of a ß-glucan prebiotic on kidney function, uremic toxins and the gut microbiome in stage 3 to 5 CKD participants. Fifty-nine participants were randomized to either the ß-glucan prebiotic intervention group (n = 30) or the control group (n = 29). The primary outcomes were to assess kidney function (urea, creatinine and glomerular filtration rate), plasma levels of total and free levels of uremic toxins (p-cresyl sulfate (pCS), indoxyl-sulfate (IxS), p-cresyl glucuronide (pCG) and indoxyl 3-acetic acid (IAA) and gut microbiota using 16S rRNA sequencing at baseline, week 8 and week 14. The intervention group (age 40.6 ± 11.4 y) and the control group (age 41.3 ± 12.0 y) did not differ in age or any other socio-demographic variables at baseline. There were no significant changes in kidney function over 14 weeks. There was a significant reduction in uremic toxin levels at different time points, in free IxS at 8 weeks (p = 0.003) and 14 weeks (p < 0.001), free pCS (p = 0.006) at 14 weeks and total and free pCG (p < 0.001, p < 0.001, respectively) and at 14 weeks. There were no differences in relative abundances of genera between groups. Enterotyping revealed that the population consisted of only two of the four enterotypes: Bacteroides 2 and Prevotella. The redundancy analysis showed a few factors significantly affected the gut microbiome: these included triglyceride levels (p < 0.001), body mass index (p = 0.002), high- density lipoprotein (p < 0.001) and the prebiotic intervention (p = 0.002). The ß-glucan prebiotic significantly altered uremic toxin levels of intestinal origin and favorably affected the gut microbiome.

Understanding kidney disease in rural central Uganda - Findings from a qualitative study

As part of a multicentre study on kidney disease (ARK) undertaken in Malawi, South Africa and Uganda we undertook a social science component in Uganda to gather information on people's understandings and perceptions of a diagnosis of kidney dysfunction, treatment and treatment seeking. We recruited 46 people who had been given information about kidney dysfunction and had been found to have some, usually early, signs of mild impairment. Data were collected during two in-depth interviews. Most participants had heard of the condition, but half denied knowledge of the health status of their kidneys or receiving results of tests from the clinic team. This response may have been linked to a lack of symptoms, for those with early stage kidney dysfunction. The treatment people reported receiving caused some uncertainty about condition severity. This may be because several people were treated for other conditions (such as urinary tract infections) and did not require treatment specifically for kidney disease. In our study, participants assessed illness severity based on symptoms and treatment and compared with the progression of other conditions.

Determinants of hyperuricemia in non-dialysed chronic kidney disease patients in three hospitals in Cameroon

BACKGROUND

Chronic kidney disease (CKD) poses a substantial health burden in sub-Saharan Africa, with risk factors ranging from communicable to non-communicable diseases. Hyperuricemia has been recently identified as a factor of progression of CKD. Identifying factors associated with hyperuricemia in CKD patients would help determine interventions to reduce CKD mortality, particularly in resources limited countries. We sought to determine the prevalence and factors associated with hyperuricemia in non-dialysed CKD adult patients in Cameroon.

METHODS

This was a cross-sectional study of non-dialysed CKD patients, conducted in 3 referral nephrology units in Cameroon. Relevant clinical and laboratory data were collected using interviewer-administered questionnaires. Serum uric acid, spot urine protein and spot urine creatinine were assessed. Associations between variables were assessed using multivariate analysis. Level of statistical significance was set at α < 0.05.

RESULTS

A sample of 103 participants was included. Mean age of study participants was 55.78 ± 12.58 years, and 59.3% were men. Sixty-nine (67%) had hyperuricemia. Patient's age (OR: 1.08, 95% CI: 1.03-1.13), estimated glomerular filtration rate (OR: 0.94, 95% CI: 0.90-0.98), spot urine protein-creatinine ratio (OR: 1.83, 95% CI: 1.07-3.12), no hypertension (OR: 0.09, 95% CI: 0.02-0.46), urate lowering therapy (OR: 4.99, 95% CI: 1.54-16.16), loop diuretics (OR: 3.39, 95% CI: 1.01-11.42), obesity (OR: 6.12, 95% CI: 1.15-32.55) and no anaemia (OR: 0.04, 95% CI: 0.00-0.29) were independently significantly associated with hyperuricemia.

CONCLUSIONS

In this sample of non-dialysed CKD patients in Cameroon, about 7 out of 10 had hyperuricemia. Hyperuricemia was independently associated with patient's age, estimated glomerular filtration rate, spot urine protein-creatinine ratio, hypertension, urate lowering therapy, loop diuretics, obesity and anaemia. More studies are required to establish causal relationships between these associations.

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.

Prevalence of chronic kidney disease among the high risk population in South-Western Ghana; a cross sectional study

BACKGROUND

Chronic Kidney Disease (CKD) is a major global health problem. CKD is one of the most common complications of diabetes mellitus and hypertension and carries a risk of cardiovascular morbidity and mortality and progression to end-stage kidney disease.

OBJECTIVES

This study sought to use the 2012 Kidney Disease Improving Global Outcomes (KDIGO) definitions to establish the prevalence and risk factors for CKD among a high risk population in the Sekondi-Takoradi metropolis.

DESIGN

Cross sectional study.

SETTING

Effia-Nkwanta regional and the Takoradi Government hospitals in South Western Ghana.

PATIENTS

Two hundred eight consecutive adults with diabetes, hypertension or both.

MEASUREMENTS

Serum creatinine and urine albumin-creatinine ratio respectively. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) was used to estimate glomerular filtration rate (GFR).

METHODS

CKD was classified according to KDIGO.

RESULTS

The prevalence of CKD was 30 %: 27 % in patients with diabetes, 22 % in patients with hypertension only and 74 % in patients with both diabetes and hypertension. GFR category G3a CKD was most prevalent stage (9 %). Albuminuria was highest among people with diabetes (39 %).

LIMITATIONS

A convenience sample of patients attending clinics.

CONCLUSION

CKD was prevalent in these high-risk patients.