Effective January 4, 2023, the process for reporting the Microalbumin/Creatinine ratio was changed for situations where one of the results, microalbumin and/or creatinine, is below or above the assay’s analytical measuring range (AMR).
Historically, if one of the results components was greater than or less than the analyte’s AMR, a ratio was calculated and a greater than or less than ratio was reported.
For example, if the microalbumin concentration was <1.2 mg/dL and the creatinine 20 mg/dL the ratio was reported as <60 mcg albumin/mg creatinine.
Currently, no ratio will be calculated and the comment “Unable to calculate due to the low or high concentration of an analyte used in the calculation” will be reported.
The rationale behind this change is to prevent misinterpretation of the ratio. In the example above, the ratio can be interpreted as abnormal because the calculation is performed using 1.2 mg/dL as the result value. However, the concentration of microalbumin may be much lower, such as 0.3 mg/dL. With a microalbumin of 0.3 mg/dL and a creatinine of 20 mg/dL the ratio is 15 mcg albumin/mg creatinine. This ratio would be interpreted as normal (<30 mcg albumin/mg creatinine).
To help interpret the results of cases where the microalbumin is less than and no calculation can be performed. Consider the following.
- If the microalbumin is <1.2 mg/dL and the creatinine is ≥40 mg/dL you can consider the ratio to be normal and less than <30 mcg albumin/mg creatinine.
- If the microalbumin is <1.2 mg/dL and the creatinine is <40 mg/dL, then the ratio could possibly be abnormal and repeat testing would be recommended. Also, providers can advise patients not to consume high amounts water prior to the urine collection.
Additional comments or questions may be directed to the Chemistry Department using the Contact Us link above.
Microalbumin/Creatinine, Random Urine Epic Order Code: LAB689, Interface Order Alias: 10436, CPT 82043, 82570