Comparison of three formulae for estimation of glomerular filtration rate in severely malnourished children at tertiary care facility

Abstract

Objectives:First objective was to compare eGFR by Updated Schwartz (US) and Simple Height Independent (SHID) formula with Original Schwartz (OS) in children with Severe Acute Malnutrition (SAM). The second objective was to compare eGFR in children below and above two years.Methods:This analytic study on estimation of GFR was based on retrospective data collected from 78 children with SAM at Nutritional Rehabilitation Unit from October 2014 - March 2015. Glomerular filtration rate was calculated using serum creatinine (S. Cr) and height in Original Schwartz, US and by age in SHID equation and compared with OS as standard. Data was analyzed using descriptive statistics.Results:There were 78 children in this study. Males were 39(50%). Mean age of patients was 18±15.53 months with 62(79.48%) ≤24 months. Mean weight, height and Mid Upper Arm Cir-cumference was 5.69±2.42kg, 68.52+13.59 cm and 10±1.57 cm respectively. Mean eGFR by OS, US and SHID formula was 71.45±49.89, 58.06±3.91 and 59.33±3.73ml/min/1.73m2 respectively. There was significant difference (0.001) in mean eGFR calculated by three different formulae. Majority of children (73%) had subnormal GFR (<90 ml/min /1.73 m2). There was a significant difference in GFR ≥90ml calculated by US compared to OS (0.025) and by SHID with OS (0.04) in children below two years and no difference in children above two years. But there was no difference in other categories of eGFR calculated by either of formula in both age groups.Conclusion:We found a significant difference in eGFR in ranges above 90 ml/min/1.73 m2 by US compared to OS as well as by SHID with OS in children below two years and no difference in children above two years. Also, there was no difference in GFR categories below 90 ml/min /1.73 m2 calculated by either of formula in both age groups. So, we may conclude that either of formula can be used in clinical practice for eGFR in mild to severe renal dysfunction in severely malnour-ished children.

Correlation of Glomerular Filtration Rate (Gfr) Estimation Formulae With Measured GFR in Pediatric Oncology Patients

“…8,9 For measurement of GFR commonly used methods are inulin clearance, EDTA clearance and iohexol and 24hour creatinine clearance (Ccrl). 10 Glomerular filtration rate assessment by inulin, EDTA clearance and iohexol is cumbersome and is not routinely done in clinical settings. 24hours Crcl requires 24hours urine collection which is also not feasible especially in young children for routine use of GFR measurement.…”

“…Original Schwartz (OS): eGFR= k x height (cm)/s.cr (mg). where k=0.45 for full term : eGFR = 107.3/s.cr/Q where Q = 0.0270 x age in years + 0.2329 10.…”