Home Health ICD-9/ICD-10 Alert

Question: I read in Home Health ICD-9 Alert Volume 4, Number 7 that when you are selecting a code for a manifestation of diabetes, the code descriptor doesn't have to include the word diabetes. This got me wondering about coding for diabetic nephropathy. Do we need to have clear documentation that the nephropathy is a manifestation of diabetes in order to link it with a diabetes code? If so, how would our coding differ for a patient with diabetic nephropathy versus a patient with diabetes and nephropathy?

Answer: You cannot assume a relationship between diabetes and kidney disease.

But if the documentation indicates a link, you can code for the diabetes with fourth digit "4" to indicate the renal manifestation and follow this with the nephropathy code 583.81 (Nephritis and nephropathy, not specified as acute or chronic, in diseases classified elsewhere).

If there is no documentation of the relationship, then you should code for the two conditions separately. In this case, you would not use the fourth digit "4" in the diabetes code and you would look elsewhere in the 583 category for an appropriate nephropathy code.