Evaluation of eGFR methods in a Sub-Saharan African community-based pediatric population

doi:10.21203/rs.3.rs-3446191/v1

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Research Article

Evaluation of eGFR methods in a Sub-Saharan African community-based pediatric population

https://doi.org/10.21203/rs.3.rs-3446191/v1

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Journal Publication

published 15 Mar, 2024

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Backgrounds

Accurate eGFR assessment is crucial for early CKD detection, management and optimal medication dosing, but its validation, especially for Cystatin C-based equations, are limited in African children and adolescents with CKD. This study evaluates eGFR equations utilising Cystatin C and creatinine in this population.

Methods:

This prospective community-based cohort study assessed CKD in children aged 1 to 18 using Cystatin C and serum creatinine. We evaluated eGFR performance with the Bland-Altman plot and ROC curve. Lin's concordance assessed agreement between various equations and the reference standard (Schwartz CKiD equations). Pairwise ROC curve comparisons determined statistical differences in estimation equation performance.

Results:

The mean age of 688 children and adolescents evaluated for CKD was 7.8 (± 3.9) years, with 341 (49.6%) being male. The Pottel equation had the lowest mean bias (-3.41, 95% CI: -2.57 to -4.25), highest discriminatory power (0.989), highest accuracy across all age groups, and highest CKD detection. Bouvet's formula had the highest mean bias [-48.66 (95% CI: -50.75 to -46.57)] across all age groups, but an average ROC discriminatory power of 0.889. Zappitelli had a lower ROC discriminatory value (0.547) but a modest bias (-20.22; 95% CI -22.21 to -18.23). Lin's concordance with Schwartz CKiD was highest with Pottel (0.99) and lowest with Bouvet (0.08). Zappetti and Chehade disagreed most, but Pottel and Chehade agreed closely on equation pairwise comparisons.

Conclusion:

In African children with CKD, Pottel's height-independent equation outperformed Chehade, Zappitelli, and Bouvet in terms of ROC discriminatory value, accuracy, and Schwartz CKiD concordance.

Chronic kidney disease

estimated glomerular filtration rate

Children

Africa

Schwartz CKiD equations

Cystatin C

Chronic Kidney Disease (CKD) is a pressing global health challenge, affecting individuals in all age groups but with particular significance in the pediatric population.^{1, 2, 3} Accurate assessment of kidney function in children is pivotal for early detection, intervention, and a precise management plan for CKD.

Glomerular filtration rate (GFR) serves as a crucial indicator of renal function, and its estimation through the use of equations, such as the estimated GFR (eGFR), has become an essential tool in clinical practice. However, the applicability and accuracy of eGFR determination methods can vary significantly across diverse populations due to differences in age, ethnicity, and environmental factors.^{4, 5, 6, 7}

Sub-Saharan Africa, a region marked by its unique demographic and health landscape, presents distinct challenges and opportunities in pediatric nephrology. The pediatric population in this region faces a disproportionately higher burden of renal diseases, often in the context of prevalent infectious diseases, malnutrition, limited access to healthcare, inadequate renal supportive care resources, socioeconomic challenges, genetic predispositions and the scarcity of renal transplantation services.^{8, 9, 10, 11}. Delays in making diagnoses and a lack of awareness make it even more difficult to effectively manage CKD often at advance stages at presentation in this populatuon.³ Yet, there is a paucity of data regarding the performance of cystatin C-based eGFR determination methods or in combination with creatinine, specifically in sub-Saharan African children.

The old Schwartz equation is widely used for estimating eGFR in older African children with normal kidney function, showing good agreement with measured GFR.^{12, 13} However, it tends to overestimate GFR in infants and young children with higher renal function values.^{7, 14} The updated bedside Schwartz CKiD equation offers improved accuracy for estimating GFR in children with chronic kidney disease, and it is recommended in CKD guidelines for diagnosis and management. Many validation studies have confirmed its reliability.^{7, 15} Promising results have been observed with the Pottels’ height-independent creatinine-based equation, but limited research has evaluated cystatin C-based equations for CKD prevalence or in caption with creatinine in African children.^{16, 17} There has also been a paucity of research that compares the performance of different eGFR determination techniques in predicting CKD prevalence in the African pediatric population.¹⁸

This knowledge gap necessitates further investigation to guide research efforts, healthcare policies, and resource allocation, aimed at improving the diagnosis, management, and outcomes of pediatric CKD.

This study aims to explore the relationship between different eGFR determination techniques and their predictive capabilities in determining CKD prevalence in a population of African children. By comparing and evaluating these techniques, we intend to identify the optimal predictor that can enhance CKD diagnosis and guide appropriate intervention strategies for this vulnerable population, ultimately improving their overall health and well-being.

Study design and settings

This was a community-based study, which was part of a larger prospective cohort study, including children aged 1 to 18 years who were screened for renal disease in two of five council areas of the Ogbomosho community in Southwest Nigeria.

Sample size determination

We determined the sample size based on the estimated prevalence of 74.7 per million (p = 0.0000747) of renal disease in a population-based study, the Italkid study.¹⁹ Considering the large population of children aged 1–18 years in each of the selected council areas, exceeding 10,000 (≈ an infinite population), we estimated the prevalence of CKD within a margin of error (ε) of 0.1% at a 95% confidence level.

The minimum sample size (n) required for this study was estimated using an online sample size calculator: Raosoft (http://www.raosoft.com/samplesize.html). Consequently, a sample size of 634 was determined. Adding potential loss to follow-up, a total of 710 children were enrolled in the study.

Subjects’ selection

A multistage sampling technique was used to sample 710 children from a study population of 126,922 children aged 1–18 years, based on the 2006 National Population Census.⁴ The sampling procedure was detailed in a study on the prevalence of proteinuria using the protein-creatinine ratio.²⁰

Eligibility criteria

Inclusion criteria:

1. All children aged 1–18 years.

2. Informed consent by parents/caregivers or assent by children aged 7years and above

Exclusion criteria:

Patients with on-going diarrhoea disease,

Patients who have used systemic steroid, trimethoprim, penicillins and cephalosporins cimetidine, gemfibrozil, or Ketoacid within the past one week.

Malnourished children, amputees, and paralysis from polio were also excluded

Refusal of consent.

Instrument for the conduct of the study

A pretested proforma was used to collect relevant data from the recruited participants. This data included socio-demographic information and clinical symptoms such as fever, body swelling, dysuria, polyuria, polydipsia, polyphagia, weight loss, bone pains, skin rash, sore throat, jaundice, vomiting, and diarrhoea. Additional information was gathered on the use of herbal medication, non-steroidal anti-inflammatory drugs (NSAIDs), mercury-containing soap, bleaching cream, and antibiotics.

Clinical examination

Eligible children were examined and weighed using appropriate equipment. For children weighing less than 15 kg, the Basinet Seca® scale Model 834 (manufactured by seca GmbHD & co.kg, Hammer Steindamm 3–25, 22089, Hamburg, Deutschland) calibrated in 50g units for weight measurement. The Seca® scale Model 220 (Waymaster, England) was used to weight older children. Height was measured using a Seca® stadiometer. The body surface area was calculated using the Mosteller formula: (Height (cm) * weight (kg) / 3600)^1/2.²¹

Blood pressure was measured on the right arm in a sitting position, using appropriate cuffs, after the subjects had rested for a minimum of 30 minutes and sat quietly for 5 minutes. Elevated blood pressure was defined as average systolic blood pressure (SBP) or diastolic blood pressure (DBP) levels that were ≥ 90th percentile but < 95th percentile. In adolescents, blood pressure levels ≥ 120/80 mmHg were considered elevated. Hypertension was defined according to the 2017 Clinical Practice Guideline (CPG) normative chart, which classified average SBP and/or DBP as ≥ 95th percentile for gender, age, and height, measured on at least three occasions using a clinical mercury sphygmomanometer.²²

Laboratory measurements

We measured serum creatinine using the modified Jaffe's reaction standardized to Isotope Dilution Mass Spectrometry (IDMS). Serum cystatin C was determined using the principle of particle-enhanced immunoturbidimetry (PETIA) with a Roche-Hitachi Cobas c311 automatic biochemical analyzer (manufactured by Roche Diagnostics GmbHD-68298 Mannheim, Germany).

Follow up assessment

Subjects with persistently impaired eGFR, < 60 ml/min/1.73 m², based on repeat serum creatinine and cystatin C measurements for at least three months were observed for eight months.

Estimated glomerular filtration rate equations in children

This study looked at four equations: one that used cystatin C (Zappitelli), one that used serum creatinine alone (Pottel), and two that combined both (Chehade and Bouvet).^{23, 24} In Zappitelli, Chehade, and Bouvet, serum cystatin C was measured using a particle-enhanced nephelometric immunoassay (PENIA), and serum creatinine was measured using Jaffes methods that were standardised using IDMS-traceable National Institute of Standards and Technology Standard Reference Material for Pottel, Chehade, and Bouvet equations.^{23, 24} The details are shown in Table 1.

Table 1

Estimated glomerular filtration rate equations in children
Authors	eGFR Equation
Zappitelli	75.94/(CysC^1.17)
Chehade	0.42(Ht/Scr) – 0.04(Ht/Scr)² – 14.5CysC + 0.69age + 18.25 if female or + 21.88 if male
Pottel and colleagues	107.3/(Scr/Q) Q = 0.0270 x age + 0.2329
Bouvet	63.2 × (CysC/1.2)^0.56 × (Scr[umol/l]/96)^0.35 × (weight/45)^0.30 × (age/14)^0.40
Updated Schwartz (CKiDCr)	0.413 × Ht or L/Scr
eGFR, estimated glomerular filtration rate; CysC, serum cystatin C in mg/L; Ht or L, height or length in cm for children younger than 2 years; Scr, serum creatinine in mg/dL; age in years; and weight in kg.

Statistical analysis

Data entry and analysis were performed using IBM SPSS Statistics for Windows, version 23 (IBM Corp., Armonk, N.Y., USA) and GraphPad Prism 9 (GraphPad Software, 2365 Northside Dr. Suite 560 San Diego, CA 92108). The continuous variables (age, height, weight, serum creatinine and cystatin C) were summarised as means with standard deviations. For normally distributed variables, means were compared using Student t-test and ANOVA. The prevalence of CKD was expressed as a percentage with a 95% confidence interval.

The performance of the eGFR technique was evaluated with Bland-Altman plot and Receiver Operating Characteristics Curve. For the Bland-Altman plot, the difference between eGFR from the various formulae and eGFR from the revised Schwartz formula was regressed against the mean of the eGFR from both methods. We defined the mean bias as mean differences of the various formulae compared with the revised Schwartz-CKiD (the reference used for this study as recommended by the guidelines) and expressed along with upper and lower limits of agreements.²⁵ Our desired mean bias was set at less than 5 ml/ min/1.73m².²⁶ Accuracy was defined as percentage of eGFR that fell within 30% of obtained values, using revised Schwartz/CKiD formula as reference and the Lin's concordance reported. The prevalence of CKD was defined as eGFR below 60 ml/min/1.73m². A significance level of p < 0.05 was used.

General characteristics of the study population

A total of 688 children and adolescent were studied during the period. The mean (standard deviation) age was 7.8 (3.9) years and 341 (49.6%) were males. The mean weight was 22.0 (9.0) kg, and mean height was 117.4 (21.9) cm. Further details are shown in Table 2. The overall mean serum creatinine was 0.45 (0.14) mg/dl while the mean serum cystatin C was 0.87 (0.15) mg/L. There was no significant sex difference in mean anthropometrics, serum creatinine, and cystatin C levels.

Table 2

General characteristics of the children and adolescents
Variable n = 688	Overall Mean (SD)	Sex		P value
Variable n = 688	Overall Mean (SD)	Male (n) = 341	Female (n) = 347	P value
Age, years	7.77 (3.93)	7.73 (4.11)	7.80 (3.73)	0.782
Height, cm	117.38 (21.94)	116.87 (22.15)	117.88 (21.76)	0.545
Weight, kg	21.97 (9.01)	21.91 (9.03)	22.02(9.00)	0.864
Body surface area, m²	0.84 (0.24)	0.84 (0.25)	0.84(0.24)	0.753
Serum creatinine, mg/dl	0.45 (0.14)	0.45 (0.14)	0.45(0.13)	0.853
Cystatin C, mg/L	0.87 (0.14)	0.88 (0.14)	0.87(0.14)	0.284
(SD), standard deviation

Comparison of the various eGFR determination techniques:

Agreement between the Pottel’s formula (creatinine-based height independent validated in sub-Saharan Africa) compared with Schwartz formula/CKiD formula. ²⁷

The mean bias (defined as mean differences between the eGFR using Pottel’s formula compared with revised Schwartz formula/CKiD formula) was − 3.41 (95% CI -2.57 to -4.25), with a lower limit of agreement of -25.43 (95% CI -26.87 to -23.99) and an upper limit of agreement of 18.61 (95% CI 17.17 to 20.05) as shown in Fig. 1.

Agreement between the Zappitelli formula (Cystatin C based found reliable among Nigerian children) compared with the revised Schwartz formula/CKiD formula.²⁸

The mean bias (defined as mean differences between the eGFR using the Zappitelli formula compared with revised Schwartz formula/CKiD formula was − 20.22 (95% CI -22.21 to -18.23) with a lower limit of -72.35 (95% CI: -75.76 to -68.95) and an upper limit of 31.91 (95% CI: 28.50 to 35.31), Fig. 2.

Agreement between Chehade formula (combined creatinine and Cystatin C, validated among Caucasians) compared with the revised Schwartz formula/CKiD formula. ²⁹

The mean bias (defined as mean differences between the eGFR using Chehade’s formula compared with revised Schwartz formula/CKiD formula) was − 16.79 (95% CI: -17.95 to -15.63), a lower limit of -47.23 (95% CI: -49.21 to -45.24) and an upper limit of 13.65 (95% CI: 11.66 to 15.64), Fig. 3.

Agreement between the Bouvet formula (combined creatinine and Cystatin C, validated among Caucasians) compared with revised Schwartz formula/CKiD formula.²⁴

The mean bias (defined as mean differences between the eGFR using Bouvet’s formula compared with revised Schwartz formula/CKiD formula) was − 48.66 (95% CI: − 50.75 to -46.57), lower limit of agreement of -103.29 (95% CI: -106.85 to -99.72) and upper limit of agreement of 5.97 (95% CI: 2.40 to 9.54), Fig. 4

Performance of the formulae for eGFR based on age groups

Compared with Schwartz-CKiD formula-based creatinine derived eGFR, Pottel’s equation showed least bias and most accurate at various age groups, with the best performance in those aged five to ten years. In contrast, Bouvet’s derived eGFR show more bias with poor accuracy at the various age groups compared with Schwartz bedside equation. Further details are shown in Table 3a.

Table 3

a: Performance of eGFR formulae for different age groups
Variable /Formula*		Age, years
Variable /Formula*		< 5, n = 172	5–10, n = 350	> 10, n = 166
Pottel	Mean bias (95% CI)	-11.53 (-12.84 to -10.23)	-4.36 (-5.33 to -3.38)	7.001 (5.60 to 8.41)
	Accuracy (95% CI)	98.20 (94.90 to 99.61)	99.10 (97.45 to 99.80)	98.20 (94.82 to 99.63)
Zappitelli	Mean bias (95% CI)	-23.51 (-28.09 to -18.93)	-19.11 (-21.84 to -16.37)	-19.17 (-22.72 to -15.62)
	Accuracy (95% CI)	69.8 (62.35 to 76.56)	78.9 (74.25 to 83.05)	80.1 (73.21 to 85.89)
Chehade	Mean bias (95% CI)	-22.56 (-24.91 to − 20.22)	-16.573 (18.18 to -14.97)	-11.26 (-13.38 to -9.14)
	Accuracy (95% CI)	94.80 (90.34 to 97.60)	95.10 (92.29 to 97.11)	99.40 (96.69 to 99.98)
Bouvet	Mean bias (95% CI)	-74.91 (-78.65 to -71.17)	-47.11 (-49.33 to -44.89)	-24.71 (-27.58 to -21.84)
	Accuracy (95% CI)	0.00 (0.0 to 2.12)	17.40 (13.58 to 21.79)	76.50 (69.31 to 82.72)
*Revised Schwartz/CKiD formula Mean (95% CI)	112.91 (110.95 to 114.88)	117.61 (113.40 to 121.81	112.45 (109.72 to 115.17)	109.04 (105.27 to 112.80)
*Reference for the comparison.CI, confidence interval. Accuracy was defined as percentage of eGFR that falls within 30% of obtained, using the revised Schwartz/CKiD formula. Bias was the mean differences of the respective formula compared with revised Schwartz/CKiD formula.

Table 3

**b. Concordance between Schwartz formula/CKiD and other estimation equations**
eGFR equation	Lin’s concordance correlation coefficient with revised Schwartz CKiD	95% Confidence interval	Precision	Accuracy
Pottel	0.99	0.88–0.91	0.91	0.99
Chehade	0.54	0.51–0.56	0.92	0.58
Zappitelli	0.27	0.22–0.32	0.38	0.71
Bouvet	0.08	0.06–0.11	0.28	0.30

Concordance between Schwartz formula/CKiD and other estimation equations

On the basis of concordance, precision and accuracy, the Pottel formula outperformed other equations. Bouvet performed least of all of the evaluated eGFR estimation equations as shown in Table 3b.

The receiver operating characteristics curve

The Pottel’s equation had an area under the curve of 0.989 [95% CI; (0.978 to 0.996)] followed by Chehade. Other details are in Fig. 5.

The Pairwise comparison of ROC curves

A pairwise comparison of the ROC for the four GFR estimation equations is presented in Table 4. The Pottel and Chehade formulas had the highest degree of agreement, whereas the Chehade and Zappetelli estimates had the greatest degree of disagreement.

Table 4

The Pairwise comparison of ROC curves
eGFR equation	Difference between AUC	Standard Error	95% Confidence interval	P-value
Chehade vs Pottel	0.0177	0.0159	-0.0135 to 0.0489	0.2656
Bouvet vs Chehade	0.0821	0.0351	0.0133 to 0.151	0.0194
Bouvet vs Zappitelli	0.342	0.116	0.115 to 0.570	0.0032
Bouvet vs Pottel	0.0999	0.0333	0.0345 to 0.165	0.0027
Pottel vs Zappitelli	0.442	0.136	0.176 to 0.709	0.0012
Chehade vs Zappitelli	0.425	0.128	0.174 to 0.675	0.0009

Prevalence of Chronic Kidney Disease among the studied children and adolescents

Based on performance, out of the four formulae (Schwartz-CKiD, Pottel, Zappitelli, and Chehade), Pottel formula has the highest prevalence of CKD detected at three months. In contrast, Bouvet formula gave an exaggerated prevalence of 43.5%, (Table 5).

Table 5

eGFR derived equations and prediction of CKD among 688 children and adolescents
Variable /Formula	Number diagnosed with CKD, eGFR < 60ml/min/1.73m²	Percentage (95% CI) *
Schwartz-CKiD	7	1.01 (0.41–2.08)
Pottel	12	1.74 (0.90–3.02)
Zappitelli	7	1.01 (0.41–2.08)
Chehade	3	0.43 (0.09–1.26)
Bouvet	299	43.46 (39.72–47.26)
*Prevalence of CKD eGFR < 60ml/min/1.73m² and it 95% confidence interval

This study aimed to determine the most accurate equation for estimating GFR in children. It examined the potential of equations that use serum creatinine or Cystatin C alone or in combinations as indicators of kidney disease using the revised Schwartz CKiD formula as the reference standard.

Among the evaluated equations, the Pottel height-independent equation had the highest discriminant value, accuracy, precision, and agreement with the validated Schwartz CKiD formula.

The Pottel equation, suitable for populations with high stunted growth rates, provides simplicity by using readily available serum creatinine as a biomarker and not depending on height as a factor.^{26, 27} The adaptability of the Pottel equation enhances its accessibility, particularly in resource-limited settings, where comprehensive biomarker panels are scarce. Its accurate GFR estimation from a single biomarker aligns with existing literature, reinforcing our report's credibility.^{16, 17, 28}

On the other hand, the Bouvet equation exhibited the lowest precision and accuracy in eGFR estimation, suggesting that it may not effectively estimate eGFR in African children with values below 60 ml/min/1.73 m2, in tandem with its performance in Canadian children as reported by Sharma et al.²⁹ Despite prior studies^{30, 31} highlighting the efficacy of GFR estimation equations using combined kidney disease biomarkers (e.g., Bouvet), our findings emphasize the need to assess equation performance across a range of GFR levels.²⁴ The Bouvet equation, despite its use of biomarkers, performed poorly compared to the Pottel equation, which relied solely on serum creatinine. This underscores the significance of serum creatinine and the need to choose the most accurate equation for assessing renal function in specific populations.³² It is also significant to acknowledge that the performance of equations depends on their context of development.

The similar performance of Chehade and Pottel equations in our study may be due to their shared characteristic of not being heavily influenced by height, unlike other equations. While Pottel is explicitly height-independent, Chehade accommodates children with various height statuses.^{24, 33}

Our study revealed that estimation equations varied in accuracy and ability to classify measured GFR correctly. Bouvet exhibited superior discrimination but lower accuracy when compared to Zapettelli's equation in estimating eGFR. This highlights the importance of considering both aspects when selecting the most suitable CKD equation for a specific context. This is significant due to the far-reaching implications of CKD diagnosis, including economic consequences, psychological impact on patients and families, and other intangible effects on individuals. An optimal eGFR estimation formula should excel in both discrimination and accuracy. The Chehade and Pottel formulae meet these criteria for screening CKD in children.

Our study, like all others, has strengths and limitations. This community-based study, which used serum creatinine and cystatin C to evaluate participants with different levels of renal function in real-world settings, has shown that our eGFR estimation method is accurate and may have applicability across populations. This makes it an ideal screening tool for children at risk of developing chronic kidney disease. Additionally, the larger sample size in our study further enhances its external validity.

We used the pediatric Schwartz CKiD equation as our benchmark instead of measured GFR, which is the standard approach. GFR measurement may not be feasible in a community setting.

The Schwartz CKiD equation was validated against iohexol-GFR, achieving 87.7% agreement within 30% of the iohexol-GFR estimates and 45.6% agreement within 10% of the iohexol-GFR estimates, supporting its validity as a reference standard.³⁴

Due to limited funding and the prohibitive cost of enzymatic assays, we utilized the more affordable Jaffe's method for serum creatinine measurements in our study. Comparisons were made using the Schwartz CKiD equation, which relies on enzymatic assays known for accuracy at lower creatinine levels, despite the study's focus on individuals with lower GFR (higher creatinine values). However, the Jaffe method tends to overestimate serum creatinine at low concentrations due to non-creatinine interferences.

Standardizing the Jaffe method to IDMS National Institute of Standards and Technology Standard Reference Material (NIST SRM) 967 demonstrated comparable accuracy to IDMS traceable enzymatic assays, offering a practical alternative. We corrected the Jaffe method using the IDMS traceable creatinine equation which make the old Schwartz formula unsuitable. Caution is advised in interpreting the data, as estimated eGFRs may be inaccurately low. Consequently, this study may have overdiagnosed or misclassified CKD due to incomplete elimination of chromogenic interference by the IDMS traceable technique.

In an African pediatric population with chronic kidney disease, the Pottel height-independent equation demonstrated superior performance in estimating eGFR from serum creatinine compared to two biomarker-based formulas. It's important to approach these results with caution, as Jaffe's method may lead to an overestimation of serum creatinine levels.

Ethical Approval

Ethical approval for the study was obtained from the Oyo State Research Ethical Review Committee, Ministry of Health Secretariat, Ibadan, with approval number AD13/479/948.

Consent to participate

Written Informed consent was obtained from the parents or caregivers, and assent was obtained from children aged seven years and above.

Consent to Publication

Not applicable

Statement of methods and guideline compliance

All methods were carried out in accordance with relevant guidelines and regulations.

Data Availability Statement

The data is available to editors, reviewers and readers without any restriction when required.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest concerning the research, authorship, and/or publication of this article.

Funding

The author(s) received financial support for the work from The ISN Clinical Research Program (https://www.theisn.org/blog/2020/09/02/clinical-research-program-spotlight-alao-michael-abel-studies-community-based-prevalence-of-ckd-in-southwest-nigeria/ ISN-CRP 2016).

Authors Consent

The author(s) of this article disclosed no potential conflicts of interest in relation to its research, authorship, or publication.

Each author has given their final approval and accepted responsibility for all aspects of the work, ensuring the integrity and accuracy of this manuscript.

The corresponding author Alao Michael Abel will serve as guarantor for the manuscript.

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published 15 Mar, 2024

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Editorial decision: Major Revisions Needed
09 Nov, 2023
Reviewers agreed at journal
17 Oct, 2023
Reviewers invited by journal
16 Oct, 2023
Editor assigned by journal
16 Oct, 2023
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Evaluation of eGFR methods in a Sub-Saharan African community-based pediatric population

Status:

Journal Publication

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Abstract

Backgrounds

Methods:

Results:

Conclusion:

Figures

Introduction

Methods

Study design and settings

Sample size determination

Subjects’ selection

Eligibility criteria

Instrument for the conduct of the study

Clinical examination

Laboratory measurements

Follow up assessment

Estimated glomerular filtration rate equations in children

Statistical analysis

Results

General characteristics of the study population

Comparison of the various eGFR determination techniques:

Performance of the formulae for eGFR based on age groups

Concordance between Schwartz formula/CKiD and other estimation equations

The receiver operating characteristics curve

The Pairwise comparison of ROC curves

Prevalence of Chronic Kidney Disease among the studied children and adolescents

Discussion

Conclusion

Declarations

References

Supplementary Files

Status:

Journal Publication

Version 1