Diagnosis coding for coexisting diabetes, hypertension, and chronic kidney disease


My clinician is asking which condition should be coded as causal to chronic kidney disease – hypertension or diabetes – when both are present. Specifically, clinicians are asking, “Why do we need to add the cause of CKD? We cannot be sure whether the cause was HTN versus Diabetes versus heart failure. We don’t always see specialists coding this way so some additional clarification would be helpful.”


This is a frequent concern from clinicians and coders alike. It is so common, in fact, that it was addressed by the American Hospital Association (AHA) Coding Clinics in October 2018. In essence, the answer is to report both diabetic chronic kidney disease and hypertensive chronic kidney disease. ICD-10-CM guidelines instruct us to presume these causal relationships. AHA would rather have prevalence data about comorbidities than to task clinicians with the formidable, and often impossible, task of determining which condition was truly causal. Thus, if a patient has Type 2 diabetes mellitus, hypertension, and stage 3a chronic kidney disease, report E11.22, I12.9 and N18.31. (Remember, for type 2 diabetes also code for any long-term medication use.)