Prevalence and distribution of primary glomerular diseases in Africa: a systematic review and meta-analysis of observational studies.

Glomerulonephritis (GN) is a predominant cause of kidney failure in Africa. The prevalence of primary GNs varies widely across Africa depending on the relative proportion of secondary GNs and genetic predispositions. We assessed the overall and sub-regional prevalence of primary GN and its histologic subtypes in Africa. We searched PubMed, EMBASE and African Journals Online for studies of biopsy-proven primary GNs across all age groups in Africa published between 2010 and 2022. Data for primary GNs [minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN), mesangioproliferative GN (MesPGN), membranoproliferative GN (MPGN), post-infectious GN (PIGN), IgA Nephropathy (IgAN), and crescentic GN (CresGN)] were extracted. Pooled prevalence was determined using the random effects model. Seventeen eligible articles (n = 6,494 individuals) from 8 African countries met the inclusion criteria. The overall pooled prevalence of FSGS, MCD, MN, MPGN, MesPGN, PIGN, IgAN and CresGN was 26.10%, 22.40%, 8.40%, 6.40%, 6.40%, 2.60%, 2.60%, 1.40%, respectively. Only 4 studies (23.5%) used light microscopy (LM), immunofluorescence (IF), and electron microscopy (EM) for diagnosis. There were significant differences in the distribution of histologic subtypes in the paediatric compared to the adult population and across geographic sub-regions, with West Africa having a higher prevalence of FSGS. Overall, the dominance of FSGS across most regions and age groups has implications for disease diagnosis and ongoing care. Research efforts to understand the impact of this trend on kidney disease outcomes and efforts to improve kidney biopsy practice as a means of early disease detection are needed in Africa.

The case for increased peritoneal dialysis utilization in low- and lower-middle-income countries.

Peritoneal dialysis (PD) has several advantages compared to haemodialysis (HD), but there is evidence showing underutilization globally, especially in low-income and lower-middle-income countries (LLMICs) where kidney replacement therapies (KRT) are often unavailable, inaccessible, and unaffordable. Only 11% of all dialysis patients worldwide use PD, more than 50% of whom live in China, the United States of America, Mexico, or Thailand. Various barriers to increased PD utilization have been reported worldwide including patient preference, low levels of education, and lower provider reimbursement. However, unique but surmountable barriers are applicable to LLMICs including the excessively high cost of providing PD (related to PD fluids in particular), excessive cost of treatment borne by patients (relative to HD), lack of adequate PD training opportunities for doctors and nurses, low workforce availability for kidney care, and challenges related to some PD outcomes (catheter-related infections, hospitalizations, mortality, etc.). This review discusses some known barriers to PD use in LLMICs and leverages data that show a global trend in reducing rates of PD-related infections, reducing rates of modality switches from HD, and improving patient survival in PD to discuss how PD use can be increased in LLMICs. We therefore, challenge the idea that low PD use in LLMICs is unavoidable due to these barriers and instead present opportunities to improve PD utilization in LLMICs.

Prevalence of Chronic Kidney Disease as a Marker of Hypertension Target Organ Damage in Africa: A Systematic Review and Meta-Analysis.

INTRODUCTION: Hypertension is a major global cause of cardiovascular disease and death with rising worldwide prevalence, particularly in low-income countries. With low awareness, poor treatment, and low control of hypertension in Africans, there is an increased number of patients with target organ damage (TOD), especially chronic kidney disease (CKD), as a consequence of hypertension. The aim of our study is to assess the prevalence of CKD from studies in Africa reporting TOD related to hypertension. METHODS: We performed a search of PubMed/MEDLINE, Web of Science, EBSCOhost, and African Journals Online (AJOL) for studies reporting on CKD as TOD in patients with hypertension. The pooled estimate of CKD was then presented by subregions, age group, eGFR equations, and urban or rural location. RESULTS: We identified 1,334 articles from which 12 studies were included for quantitative analysis. The studies included 5297 participants from 6 countries (Ghana, Nigeria, Uganda, Tanzania, Democratic Republic of Congo, and South Africa). The pooled prevalence of CKD was 17.8% (95% CI 13.0-23.3%), and CKD was significantly more prevalent in West Africa (21.3% (95% CI: 16.1-27.0); p < 0.0001) and in studies conducted in urban settings (p < 0.001). CKD prevalence was not significantly different by type of GFR equation or age. CONCLUSION: This study reports a high prevalence of CKD related to hypertension with a higher prevalence in urban than rural areas. This emphasizes the role of hypertension in causing kidney damage, and the need for strategies to improve awareness, treatment, and control of hypertension in Africans. This study is registered with PROSPERO registration number CRD42018089263.

A Systematic Review of Complications Associated With Percutaneous Native Kidney Biopsies in Adults in Low- and Middle-Income Countries.

INTRODUCTION: Kidney biopsy is an important tool for making diagnoses and for assessing the drug treatment requirements and disease prognosis in the management of kidney diseases. There are variations in the rate of complications associated with kidney biopsies across countries, and this depends on various clinical and technical factors. The aim of this study is to report on complications associated with kidney biopsy performed in low- and middle-income countries. METHODS: Two reviewers searched studies in MEDLINE, Embase, Cochrane Reviews, and African Journals Online. A random effects meta-analysis method was used to pool estimates of complications. RESULTS: We identified 39 studies reporting on 19,500 kidney biopsies with overall complications (major + minor) rate of 14.9% (95% confidence interval = 11.4%-18.7%). Fewer complications were reported in biopsies performed with real-time ultrasound scans compared to those pre-marked using ultrasound or blind procedures (12.4% vs. 14.9% vs. 24.5%; P = 0.037), respectively. Complications, albeit lower for procedures performed with automated needles (13.3%), were not significantly different from those performed with nonautomated needles (17.3%; P = 0.588). Major complications included macroscopic hematuria (1.48%), nephrectomy (0.04%), blood loss requiring red cell transfusion (0.24%), angiographic intervention (0.22%), and death (0.01%). CONCLUSION: Complications associated with kidney biopsy in low- and middle-income countries are low, are comparable to those in other settings, and occur more sparingly when real-time ultrasound techniques or automated kidney biopsy needles are used. This suggests the need to expand the use of this procedure to improve diagnosis of kidney pathologies and choice of therapy when indicated.

Diagnostic performance of glomerular PLA2R and THSD7A antibodies in biopsy confirmed primary membranous nephropathy in South Africans.

BACKGROUND: Serum and tissue-based tests using phospholipase A2 receptor 1 (PLA2R) and thrombospondin type-1 domain containing 7A (THSD7A) are established immune biomarkers for the diagnosis of primary membranous nephropathy (PMN). This study assessed the diagnostic performance of these biomarkers in the diagnosis of PMN in South Africans. METHODS: This was a cross-sectional analysis from a single centre in Cape Town, South Africa. Relevant biodata was collected from all patients. Histology, including slides for PLA2R and THSD7A were processed and assessed by typical microscopic and immunohistochemical features. Biopsy tissues of patients with membranous lupus nephritis (LN-V) and diabetic nephropathy (DN) were used as controls. The diagnostic accuracy for diagnosis of PMN using positive PLA2R and THSD7A were evaluated. RESULTS: Of the 88 patients included, 41 had PMN with a mean age of 44.5 ± 17.5 years and 61.0% were female. Histologically, PLA2R and THSD7A were only positive in the PMN group (51.2% and 4.9%, respectively) but negative in both control groups. The sensitivity of PLA2R and THSD7A for identifying PMN was 51.2% and 4.9%, respectively. The sensitivity of both tests together was 53.7% while the specificity and positive predictive values (PPV) for any of the tests (alone or in combination) was 100%. There was no difference in the sensitivity and specificity when using PLA2R alone compared to combining the two tests (p=0.32). CONCLUSION: Glomerular staining of PLA2R and THSD7A could have potential diagnostic values in South Africans. This has implications on how immunotherapies can be initiated and used in these settings.

Prevalence of peritonitis and mortality in patients with ESKD treated with chronic peritoneal dialysis in Africa: a systematic review.

OBJECTIVE: The aim of this study was to report the prevalence of peritonitis and mortality in patients with end-stage kidney disease (ESKD) treated with chronic peritoneal dialysis (PD) in Africa. DESIGN: Systematic review. SETTING: Africa. PARTICIPANTS: Patients with ESKD in Africa. INTERVENTIONS: PD in its varied forms. PRIMARY AND SECONDARY OUTCOMES: PD-related peritonitis rate (primary outcome), time-to-discontinuation of PD, mortality. DATA SOURCES: Four databases, including PubMed, Embase, Web of Science and Africa Journal Online were systematically searched from 1 January 1980 to 31 December 2019. ELIGIBILITY CRITERIA: Studies conducted in Africa reporting peritonitis rate and mortality in patients treated with PD. DATA EXTRACTION AND SYNTHESIS: Two reviewers extracted and synthesised the data using Microsoft Excel. The quality of included data was also assessed. RESULTS: We included 17 studies from seven African countries representing 1894 patients treated with PD. The overall median age was 41.4 years (IQR: 38.2-44.7) with a median time on PD of 18.0 months (17.0-22.6). An overall median peritonitis rate of 0.75 (0.56-2.20) episodes per patient-year (PPY) was observed and had declined with time; peritonitis rate was higher in paediatric studies than adult studies (1.78 (1.26-2.25) vs 0.63 (0.55-1.87) episodes PPY). The overall median proportion of deaths was 21.1% (16.2-25.8). Culture negative peritonitis was common in paediatric studies and studies that reported combined outcomes of continuous ambulatory PD and automated PD. Both 1-year and 2-year technique survival were low in all studies (83.6% and 53.0%, respectively) and were responsible for a high proportion of modality switch. CONCLUSIONS: Our study identifies that there is still high but declining peritonitis rates as well as low technique and patient survival in PD studies conducted in Africa. Sustained efforts should continue to mitigate factors associated with peritonitis in patients with ESKD treated with PD in Africa. PROSPERO REGISTRATION NUMBER: CRD42017072966.

Comparing the Efficacy and Safety of Induction Therapies for the Treatment of Patients with Proliferative Lupus Nephritis in South Africa.

BACKGROUND: Lupus nephritis (LN) can be complicated with requirement for kidney replacement therapy and death. Efficacy of induction therapies using mycophenolate mofetil (MMF) or intravenous cyclophosphamide (IVCYC) has been reported from studies, but there is limited data in Africans comparing both treatments in patients with proliferative LN. METHODS: This was a retrospective study of patients with biopsy-proven proliferative LN diagnosed and treated with either MMF or IVCYC in a single centre in Cape Town, South Africa, over a 5-year period. The primary outcome was attaining complete remission after completion of induction therapy. RESULTS: Of the 84 patients included, mean age was 29.6 ± 10.4 years and there was a female preponderance (88.1%). At baseline, there were significant differences in estimated glomerular filtration rate (eGFR) and presence of glomerular crescents between both groups (p ≤ 0.05). After completion of induction therapy, there was no significant difference in remission status (76.0% versus 87.5%; p=0.33) or relapse status (8.1% versus 10.3%; p=0.22) for the IVCYC and MMF groups, respectively. Mortality rate for the IVCYC group was 5.5 per 10,000 person-days of follow-up compared to 1.5 per 10,000 person-days of follow-up for the MMF group (p=0.11), and there was no significant difference in infection-related adverse events between both groups. Estimated GFR at baseline was the only predictor of death (OR: 1.0 [0.9-1.0]; p=0.001). CONCLUSION: This study shows similar outcomes following induction treatment with MMF or IVCYC in patients with biopsy-proven proliferative LN in South Africa. However, a prospective and randomized study is needed to adequately assess these outcomes.