Home Health ICD-9/ICD-10 Alert

Question: Our patient has cellulitis of the foot with an open wound caused by swelling and tightness of the skin due to the cellulitis. How should I code for this? Which diagnosis should be primary -- the wound or the cellulitis?

Washington Subscriber

Answer: Cellulitis is an inflammation or infection of the subcutaneous tissue. The bacteria have to be able to get into the subcutaneous tissue, usually via a wound, to cause an infection. So, the general rule is that you code the wound first and then the cellulitis.

However, in your patient's case, there may be no evidence that indicates how the cellulitis started, and your question indicates that the cellulitis caused the wound. This wound may be an ulcer or a superficial injury. In this case, code for the cellulitis first and then the wound. For example:

• M1020a: 682.7 (Other cellulitis and abscess; foot, except toes) and
• M1022b: 707.14 (Ulcer of heel and mid foot).