Toxic effect of unsp corrosive substance, assault, sequela

This code indicates a long-term or late-occurring health problem resulting from an intentional act of poisoning by an unspecified corrosive substance. The initial acute injury has resolved, and the patient is now experiencing residual effects.

Apply this code when documenting a sequela (e.g., esophageal stricture, chronic skin scarring, vision impairment) that is directly attributable to a past assault involving an unknown corrosive agent. This code is appropriate for encounters where the focus is on managing these chronic complications, not the initial acute poisoning.

• Requires a seventh character "S" to denote sequela, indicating the late effects of the initial injury.
• Only use when the specific corrosive substance is not documented or cannot be determined.
• Always sequence this code after the code(s) for the specific sequela being treated (e.g., K22.2 for esophageal stricture).