Related Experiment Video
Updated: Oct 6, 2025
Author Spotlight: Repetitive Transcranial Magnetic Stimulation Combined with Movement Observation in Cerebral Palsy
Published on: August 9, 2024
Comparing Cystatin C- and Creatinine-Estimated Glomerular Filtration Rates in Patients With Thoracic Versus Sacral
Amanda K Morrow1, T Andrew Zabel, Jennifer Dodson
1From the Department of Pediatric Rehabilitation Medicine, Kennedy Krieger Institute, Baltimore, Maryland (AKM, SAK); Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, Maryland (AKM, SAK); Department of Rehabilitation Services, Mt Washington Pediatric Hospital, Baltimore, Maryland (AKM); Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, Maryland (TAZ); and Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland (JD).
Objective:
Patients with myelomeningocele-type spina bifida are at increased risk of developing kidney disease from neurogenic bladder. Differences between creatinine- and cystatin C-estimated glomerular filtration rates were examined in patients with thoracic versus sacral level myelomeningocele given presumed differences in muscle mass.
Design:
A retrospective chart review (2005-2018) was performed on 57 adults with myelomeningocele [thoracic n = 44 (77%); sacral n = 13 (23%)]. Concurrently obtained creatinine and cystatin C levels were extracted and calculated creatinine- and cystatin C-estimated glomerular filtration rates were compared.
Results:
Mean creatinine-estimated glomerular filtration rate was significantly higher for thoracic [140.8 ml/min (SD = 23.9)] versus sacral myelomeningocele [112.0 ml/min (SD = 22.6), P = 0.0003]. There was no difference in cystatin C-estimated glomerular filtration rate between sacral [116.6 ml/min (SD = 23.7)] and thoracic myelomeningocele [124.8 ml/min (SD = 17.9)]. The mean difference between creatinine- and cystatin C-estimated glomerular filtration rates in thoracic myelomeningocele [24.2 ml/min (SD = 16.3)] was significantly greater than in sacral myelomeningocele [-12.8 (SD = 15.7), P < 0.0001].
Conclusions:
There was a significantly higher discrepancy between creatinine- and cystatin C-estimated glomerular filtration rates in thoracic versus sacral motor levels of myelomeningocele. These data suggest that creatinine-estimated glomerular filtration rate may overestimate kidney function in patients with thoracic myelomeningocele. Providers who manage patients with thoracic myelomeningocele should consider monitoring cystatin C to evaluate for underlying renal disease.
Related Concept Videos
01:28Drug Dosing in Renal Diseases: Estimation of Glomerular Filtration Rate Based on Serum Creatinine Concentration
01:25Drug Dosing in Renal Diseases: Measurement of Serum Creatinine Concentration and Clearance
01:23Renal Clearance
Renal clearance refers to the volume of plasma cleared of a specific substance, such as creatinine, per unit of time. To measure clearance, urine samples are collected over a 24-hour period during each bladder voiding, followed by a single blood sample at the...
01:17Factors Affecting Renal Clearance: Renal Impairment
One condition associated with renal failure is uremia. Uremia is characterized by impaired glomerular filtration and fluid accumulation in the body. This condition hinders the renal clearance of drugs, resulting in drug accumulation and potential...
01:24Serum Studies: Renal Function Tests