The rules for this are pretty clearly spelled out in the ICD-10-CM Official Guidelines for Coding and Reporting at the beginning of the ICD-10 coding books (see citations below). The guidelines state that if two conditions are linked in ICD-10 by the terms 'with' or 'in', then the relationship is presumed unless the provider documents that the two are not related. This is the case in both of the examples above, the first of which his also addressed in the chapter-specific guidelines. Under 'hypertension in the Alphabetic Index, you'll find 'with' and 'kidney involvement' which directs to the I12 codes. Similarly, under 'diabetes' there is an entry for 'with' and 'chronic kidney disease' that directs to the E11.22 for "diabetes mellitus with diabetic chronic kidney disease" (also containing 'with' in the code description itself). Per instructions for terms that include 'with', these should be coded as related. If the provider is documenting 'likely' or 'suspect' in these cases, that would not override the rule because the provider is not definitively stating that the two conditions are unrelated. The provider is documenting uncertainty about the relationship and not about the diagnoses themselves, but since the relationship is presumed under the classification rules, that will not change the coding in this case. Hope this helps some.
General Coding Guidelines:
The word “with” or “in” should be interpreted to mean “associated with” or “due to” when it appears in a code title, the Alphabetic Index (either under a main term or subterm), or an instructional note in the Tabular List. The classification presumes a causal relationship between the two conditions linked by these terms in the Alphabetic Index or Tabular List. These conditions should be coded as related even in the absence of provider documentation explicitly linking them, unless the documentation clearly states the conditions are unrelated or when another guideline exists that specifically requires a documented linkage between two conditions....
Chapter 9 Guidelines:
The classification presumes a causal relationship between hypertension and heart involvement and between hypertension and kidney involvement, as the two conditions are linked by the term “with” in the Alphabetic Index. These conditions should be coded as related even in the absence of provider documentation explicitly linking them, unless the documentation clearly states the conditions are unrelated.
For hypertension and conditions not specifically linked by relational terms such as “with,” “associated with” or “due to” in the classification, provider documentation must link the conditions in order to code them as related.
