Evaluation of renal dysfunction among children in the Department of Child Health, Korle-Bu Teaching Hospital, Ghana

There is an upsurge in the prevalence of kidney dysfunction among adults and children in many countries. Various screening modalities have been used in various jurisdictions but with poor reproducibility. This study therefore sought to evaluate the validity of using selected biomarkers in combination with the predictive equations for early detection of kidney dysfunction among children. In all 90 study participants’ comprising 45 patients with varied medical conditions within the case group and another 45 patients within the control group were enrolled into the study. Participants were age matched with ages ranging from 2–12 years. Blood samples, urine samples and anthropometric data were obtained from each of the study participants. eGFR was estimated using two creatinine-based equations (Schwartz and Counahan-Baratt) and four Cystatin C-based equations (Rule, Zappittelli, Larsson and Le Bricon). Respondents within the control group were significantly heavier (24.5 ± 9.8 kg) when compared with their counterparts within the case group (19.8 ± 11.3 kg; p=0.041). Age, BMI, %BF, systolic and diastolic pressures showed no statistically significant differences (p>0.05). There was significant increases in urea (5.6 ± 5.4 vs 3.1 ± 1.5 mmolL-1; p=0.004), creatinine (74.2 ± 52.4 vs 49.3 ± 10.5 μmolL-1; p=0.003) and Cystatin C (1062 ± 274.3 vs 854.7 ± 109.9 μgL-1; p<0.000) in the case group when compared to the control group. Contrarily, serum protein (56.7 ± 14.3 vs 69.5 ± 6.7 gL-1; p<0.000) and albumin (30.7 ± 10.0 vs 39.2 ± 5.0 gL-1; p<0.000) concentrations in the case group were significantly decreased when compared to the control group. Urinary albumin (3.0 ± 4.5 gL-1) and protein (4.7 ± 5.6 gL-1) concentrations for the case group were significantly higher compared with that estimated in the control group (0.2 ± 0.1 g L-1; 1.6 ± 0.9 g L-1) respectively. Urinary creatinine concentration was however decreased in the case group (3059 ± 2812 mgdL-1) compared with the control group (6971 ± 3764 mgdL-1). Proteinuria was assessed by estimating urine protein–creatinine ratio (Upr/cr). In the control group 4.4% (2/45) of respondents were normal whilst 40.0% (18/45) and 55.6% (25/45) were within the significant and nephrotic proteinuria range respectively. None of the respondents in the case group were normal, however 17.8%(8/45) and 82.2%(37/45) fell within the significant and nephrotic ranges respectively. Prevalence of CKD determined with the Schwartz and Counahan-Baratt equations within the case group was 35.6% respectively while the Larsson, Rule and Zappitelli formulae yielded a CKD prevalence of 20.0% respectively. Le Bricon, yielded a CKD prevalence of 13.3%. There was an inverse relationship between Upr/cr and GFR as estimated with the renal function estimating equations. UACR against GFR also showed an inverse relationship. Weight, age, height and proteinuria (defined by urine protein-creatinine ratio) were identified as significant predictors of progression to CKD. The Schwartz and Counahan-Baratt equations showed the best agreement with the predictors and showed a natural spread of the respondents within the case group across the five stages of CKD as defined by KDOQI guidelines.

Source: KNUST