Home Health ICD-9/ICD-10 Alert

Question: Our patient had arthroscopic surgery to repair a traumatic knee injury a month ago. She was healing well at first, but now she has a septic knee with drainage through one of the arthroscopy ports. We are seeing her for IV antibiotics and lab draws for peak and trough. Should I report the septic knee as primary or is the post-operative infection the correct primary diagnosis?

New Jersey Subscriber

Answer: List the following codes for your patient:

• M1020a: 711.06 (Pyogenic arthritis, lower leg);
• M1022b: V58.81 (Fitting and adjustment of a vascular catheter);
• M1022c: V58.83 (Encounter for therapeutic drug monitoring); and
• M1022d: V58.62 (Long-term [current] use of antibiotics).

If your patient truly has a septic knee joint, your primary diagnosis is 711.06. But if the diagnosis is actually just an infection of the surgical wound, you would code for it with 998.59 (Other postoperative infection).

Either way, follow the principal diagnosis with the appropriate V codes to indicate that you are providing and monitoring her IV antibiotics.