When both a stage of CKD and ESRD are documented, which code should be assigned?

When both a stage of chronic kidney disease (CKD) and end-stage renal disease (ESRD) are documented, the correct coding practice is to assign the code that accurately reflects the most severe condition being addressed in the documentation. In this case, N18.6 should be assigned because it specifically denotes "End stage renal disease," which encompasses all previous stages of CKD as well as indicating that the patient has reached the terminal stage of kidney disease.

Using N18.2 (stage 2 CKD) or N18.3 (stage 3 CKD) would not be appropriate because these codes reflect earlier stages of chronic kidney disease and do not account for the presence of end-stage renal disease. Additionally, utilizing I12, which relates to hypertensive heart and chronic kidney disease, does not accurately capture the essence of the patient's condition regarding the severity and end-stage classification. Therefore, N18.6 is the most accurate representation of the patient’s health status when both stages of CKD and ESRD are documented.