Blister (nonthermal) of anus, initial encounter

This code signifies the presence of a non-burn-related fluid-filled lesion on the perianal or anal skin. These blisters are typically caused by friction, irritation, or other mechanical trauma rather than heat or chemical exposure.

This code is appropriate for documenting a patient's initial presentation for evaluation and treatment of a blister in the anal region that is not due to thermal injury. Examples include blisters from prolonged sitting, tight clothing, or minor skin irritation.

• Ensure documentation clearly states the blister is non-thermal and located specifically on the anus.
• Verify this is the initial encounter for the condition; subsequent encounters will require a different seventh character.
• Consider additional codes for any underlying cause or associated symptoms if documented.