Reliability of different estimated glomerular filtration rate as measures of renal function in children with sickle cell disease.
BACKGROUND
There is no reliable marker for detecting early renal disease in early children with sickle cell disease (SCD). Estimation of glomerular filtration rate (eGFR) as derived from the height/plasma creatinine formula is dependent on the accuracy of the creatinine analytical method used. The aim of this study was to evaluate different equations for eGFR.


METHODS
Children aged 5-16 years recruited. mGFR was obtained using plasma disappearance of Inutest/Iohexol, serum creatinine (SCr) was measured either by standard laboratory method or by tandem mass spectrometry (MSMS). Estimated GFR was then calculated either by "Bedside Schwartz method" or by the full-age spectrum (FAS) equation.


FINDINGS
A total of 79 patients (mean age 9.8 ± 4.0 years). A revised eGFR constant was calculated for Schwartz equation from the slope of the plot of height/plasma creatinine versus mGFR. Mean values for mGFR (132.7 ± 32.1 ml/min/1.73m2) and eGFR methods compared: eGFR from standard SCr was significantly higher (144.2 ± 37.3 ml/min/1.73m2, p = 0.008). The MSMS eGFR showed the lowest SD (SD = 27.5), while both FAS eGFR and FAS-height eGFR showed the highest correlation coefficient (r = 0.67).


INTERPRETATION
eGFR calculation based on height and SCr determined with MSMS traceable creatinine is more reliable than Schwartz formula using jaffe/enzymatic methods in SCD children.
['Inusa|Baba Psalm Duniya|BPD|', 'Liguoro|Ilaria|I|', 'Tayo|Bamidele|B|', 'Booth|Caroline|C|', 'Turner|Charles|C|', 'Dalton|Neil R|NR|']
Glomerular filtration rate Sickle cell disease Creatinine Mass spectrometry Albuminuria Sickle cell nephropathy