Blister of shoulder and upper arm, infected

This code signifies a localized collection of fluid under the skin (blister) located on the shoulder or upper arm, which has become secondarily infected. The infection typically presents with signs such as redness, warmth, swelling, pain, and possibly purulent discharge.

Use this code when documentation clearly indicates an infected blister specifically on the shoulder or upper arm. This diagnosis is supported by physician notes detailing the presence of a blister in this anatomical area along with clinical signs of infection.

• Differentiate from non-infected blisters; if no infection is present, a different code for non-infected blisters would be appropriate.
• Consider an additional code for the underlying cause of the blister (e.g., burn, friction) if known and documented.
• Ensure the documentation specifies "shoulder" or "upper arm" to justify this specific anatomical site.