Biomedical
A sudden creatinine increase: A case report
Bernhard Strasser,
Josef Tomasits
Peer Reviewed
Abstract
Creatinine and estimated glomerular filtration rate (eGFR) are first-line laboratory parameters in the diagnosis of various renal diseases. In recent decades, cystatin C (cysC) has furthered the laboratory repertoire regarding renal status assessment and has been implemented in many clinical guidelines. Accordingly, with the establishment of cysC as a renal routine biomarker, further opportunities for assessing eGFR have been attained. Nevertheless, various limitations are still associated with cysC and creatinine analysis. Preanalytical errors could cause false results in both biomarkers. In our case, we were confronted with implausibly elevated creatinine levels due to preanalytical errors.
Key Questions and Answers
1. What caused the sudden increase in creatinine levels in the patient?
The sudden increase in creatinine levels was caused by a preanalytical error, specifically the timing of the blood sample being taken one hour postprandially, after the patient consumed a creatine-rich meal, which influenced the creatinine analysis.
2. How does food intake affect creatinine measurement?
Food intake, especially creatine-rich foods like beef, can lead to elevated creatinine levels because creatine is converted into creatinine during the cooking process. This effect is more significant in individuals with chronic kidney disease.
3. Why was cystatin C (cysC) not affected in this case?
Cystatin C (cysC) levels were not affected because it is not influenced by food intake in the same way as creatinine. Additionally, the patient did not have conditions like thyroid dysfunction that could affect cysC levels.
4. What recommendations are given to avoid such errors in laboratory settings?
To avoid such errors, it is recommended to have a fasting period of 12 hours before blood samples are taken. Additionally, adhering to appropriate patient preparation and sample handling protocols is crucial to reduce preanalytical errors.
