What is a common source of error when measuring creatinine levels using the Jaffe method?

The Jaffe method for measuring creatinine levels is known to be susceptible to interference from substances that can affect the accuracy of the test results. The presence of ketones and proteins is a notable source of error in this method.

In the Jaffe reaction, creatinine reacts with alkaline picrate to form a chromogen, which is then measured colorimetrically. However, substances that are also present in the sample, such as ketones and proteins, can react with the picrate and produce color changes independent of creatinine levels. This can lead to a positive bias in the measurement, resulting in inaccurately elevated creatinine readings.

Understanding this interference is vital for clinical settings, as accurate creatinine levels are essential for assessing kidney function and determining renal impairment. Awareness of potential interfering substances allows for proper sample handling and interpretation of results, thus improving the reliability of the test outcome.