Infective myositis, right lower leg

This code identifies an inflammatory condition of the muscles in the right lower leg caused by an infection. This infection leads to muscle pain, weakness, and swelling, specifically affecting the gastrocnemius, soleus, or other muscles below the knee on the right side.

Apply this code when documentation confirms a diagnosis of myositis directly attributable to an infectious agent (bacterial, viral, fungal, parasitic) localized to the right lower leg. Supporting documentation should include physician notes detailing the infectious etiology and the specific anatomical site.

• Always confirm the infectious nature of the myositis; otherwise, a non-infective myositis code (e.g., M60.861) may be more appropriate.
• Ensure the laterality is clearly documented as "right" and the anatomical site as "lower leg."
• Code first the underlying infectious organism (e.g., B95-B97) if known and applicable, following ICD-10-CM sequencing guidelines.