I have a patient who was seen in the ED and diagnosed with a dog bite of the right lower limb. The ED will use S91.351A as the accident code. Two days later the patient has presented again and been placed in observation but has now been diagnosed with cellulitis to the area of the bite. I know that my primary dx code will be L03.115 for the cellulitis but can I still code S91.351A? Or, should I code it as S91.351S, for sequela since another condition has arisen from the bite? Technically, we are still treating the current dog bite and it seems like I should use S91.351A, but I wanted another opinion. Any help would be appreciated.