One of my high volume referring doctors uses a lab which does not calculate the microalbumin to cr ratio. It always stops me in my tracks when I see the values.
- To convert microalbum and urine creatinine to the useful ratio first make sure both values are expressed as mg/L or mg/ml
- Divide the microalbumin concentration by the creatinine concentration
- Multiply the resulting ratio by 1,000 to get mg albumin over grams creatinine
For example a patient had the following labs:
Microalbumn urine 5.6 mg/dL
Creatinine urine 91.2 mg/dL
Dividing the albumin by cr gives: 0.061
Multiply that by 1,000 to get 61 mg albumin/g creatinine
Or you can use the free MedCalc, http://medcalc.ch, that will do the calculation for you. Note that the mg/dL unit for urinary albumin is missing in the current version, I quickly added it for the next revision.
Mathias, your excellent calculator has earned a spot on the first page of my iPhone.
Yeah, that mg/dL for urinary microalbumin threw me for a loop. Strange units.
I too have to calculate the albumin to creatinine ratio in HTN patients (why don't lab reports do this!? but I digress….). You mention that the units have to be in mg/L or mg/mL but the example above has units in mg/dL (which is the units I see most often). If they are both in mg/dL will you get the same result? Also, are you multiplying the ratio by a thousand to get the units for the creatinine in grams or are you converting the microalbumin to albumin? Thanks!