August 5, 2024
CKD as defined by NKF KDOQI:
Kidney damage for >3 months defined by structural or functional abnormalities of the kidney that can lead to decreased GFR
• For CKD to be diagnosed, one of the following criteria must be present for >3 months:
GFR <60, or Clinical markers of kidney injury with objective findings such as: Albuminuria, abnormal urine sediment, electrolyte abnormalities due to renal tubular disorders, histological and structural abnormalities, or history of renal transplant
• CKD stage is determined by the stable GFR:
Stage GFR
- >90
- 60-89
- 3a 45-59; 3b 30-44
- 15-29
- <15
ESRD Dialysis-dependent stage 5
Important note: GFR in stages 1 and 2 is >60 which does not meet the first criterion, so a diagnosis of CKD would require at least one clinical indicator of kidney injury
Provider documentation should be clear if there is a causal relationship related to the CKD to determine the most accurate code assignment.
For example, a patient is admitted with diabetes, hypertension and CKD and the provider links the CKD to the diabetes.
A causal relationship is indicated and denotes the CKD is not related to the hypertension.
Only a code for diabetic CKD would be reported.
Hypertension would be reported separately.
CKD should not be coded as hypertensive if the physician has specifically documented a different cause.
Provider documentation noting only the presence of comorbid conditions and CKD would capture a cause and effect relationship between the conditions.
For example, a patient is admitted with chronic comorbidities noted as diabetes, hypertension and CKD.
A cause and effect relationship are presumed, and the CKD is most likely related to both hypertension and diabetes.
Assign codes:
- Type 2 diabetes mellitus with diabetic chronic kidney disease
- Hypertensive chronic kidney disease with stage 1 through stage 4 chronic kidney disease
- Chronic kidney disease, unspecified
Provider documentation should be clear related to a kidney transplant status and CKD.
For example, a patient admitted to the hospital has kidney transplant failure with CKD 4.
- Principal diagnosis would be Kidney transplant failure, for complication of the transplanted kidney.
- Chronic kidney disease stage 4 would be coded as a secondary diagnosis.
- Additional Tips:
- Correct documentation of CKD stage is important- stages 4 and 5 without HD are CCs. If the stage is not documented and stable creatinine levels are present, providers should be queried for patients with a GFR < 60.
- If the patient’s history presents competing etiologies for the documented CKD (for example-a patient with polycystic kidney disease and hypertension), a query is likely required for accurate code assignment.
- The Official Guidelines for Coding and Reporting state that chapter-specific guidelines from Chapter 9 and 14 direct reporting of combination codes r/t CKD, hypertension, and diabetes. The classification presumes a causal relationship between CKD and the conditions of hypertension and heart failure. If the provider indicates the CKD is not related to the hypertension and/or heart failure, the combination code would not be assigned. A code from category N18 should also be assigned for the specific stage of CKD.
- The Official Guidelines for Coding and Reporting states that patients with a history of renal transplant should have CKD staged per the eGFR. The presence of CKD is not considered a complication. Both the specific N18 code and the Z94.0 code for kidney transplant status would be assigned.
- The providers documentation of CKD G4A3 is synonymous with stage 4 CKD and would code to N18.4 per Coding Clinic First Quarter 2023.
References:
Coding Clinic for ICD-10-CM/PCS, Fourth Quarter 2018: page 88.
Coding Clinic for ICD-10-CM/PCS, Fourth Quarter 2020: page 35.
Coding Clinic for ICD-10-CM/PCS, First Quarter 2023: page 17.
Prescott, L. & Manz, J. (2020). 2021 ACDIS Pocket Guide. The Essential CDI Resource. HCPro, 323-328.
Pinson, R. & Tang, C., (Jan, 2021). Filtering Out Confusion over Kidney Disease. Retrieved from Filtering Out Confusion Over Kidney Disease | Pinson & Tang (pinsonandtang.com)
