Cystatin C - a helpful tool for accurate drug dosing
01. Jul 2020 |
4 min read
Cystatin C based eGFR when prescribing drugs
A lot of drugs, especially antibiotics and cytotoxic drugs such as vancomycin, carboplatin, digoxin, are metabolised and excreted through the kidneys. When prescribing pharmaceuticals that have a narrow therapeutic window, it becomes exceedingly important to have an accurate understanding of the patients' Glomerular Filtration Rate (GFR), which measures the rate water and dissolved substances are filtered out of the blood per unit time.
Why is accurate dosing so important?
Prescribing too low a dose is associated with lack of efficacy and sub-optimal treatment
Too high a dose can put the patient at risk for severe side effects
Nephrotoxicity impacts on length of stay
Vancomycin: importance of correct dosing
The antibiotic drug, vancomycin is an example of a drug that has a narrow therapeutic window, and therefore thorough level monitoring is recommended [1-2]. Too low trough concentrations are associated with both clinical failure and significantly increased risk of resistance. In the other direction, too high concentrations will predict both nephrotoxicity and ototoxicity [3-5]. Cystatin C correlates closely with the mGFR, and cystatin C testing can therefore improve patient treatment. Correct dosing will also create cost savings, due to more effective treatment and shorter recovery time.
Cystatin C, drug dosing and effective patient treatment
Monitoring patient's cystatin C levels can improve patient treatment and shorten the recovery time. Correct dosing can therefore create cost savings, due to more effective treatment.
Want to learn how a hospital network in the US managed to save cost on and shorten length of stay by introducing cystatin C testing as part of vancomycin dosing and treatment. Contact our Product Manager for Cystatin C today:
Gentian Cystatin C Immunoassay advantages
The Gentian Cystatin C Immunoassay (ERM-DA471/IFCC standardised) is an in vitro diagnostic test for quantitative determination of cystatin C in human serum and plasma
Available for a wide range of clinical chemistry analysers with documented high inter-instrument accuracy 
Avian antibodies - Avoids interference with rheumatoid factor 
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