One interesting and time-saving feature of ICD-10-CM codes is the combination code. Just like Burger King, McDonald’s and other fast food eateries, the world of coding has combos; the food-oriented ones save us money and the coding combos save us time.
The 2017 ICD-10-CM Official Guidelines for Coding and Reporting state that “a combination code is a single code used to classify:
- Two diagnoses, or
- A diagnosis with an associated secondary process (manifestation)
- A diagnosis with an associated complication”
We frequently see the separate and erroneous reporting of diagnoses contained in a combination code. For example: we have seen many instances when I25.119, Atherosclerotic heart disease of native coronary artery with unspecified angina pectoris was reported in addition to I20.9, Angina pectoris, unspecified.
Coders and providers should be mindful of the coding guidelines of combo codes, and report the second code only if instructed to do so. An example of this is E11.22, Type 2 diabetes mellitus with diabetic chronic kidney disease. This combo code can be a little misleading because one might believe the kidney disease is included in the code. However, the coding guideline states that the proper stage of CKD needs to be reported in addition to E11.22.
Combos are a great aspect of ICD-10 coding, but we must make sure to understand and apply the proper guidelines when using them.