Blister (nonthermal) of left upper arm, initial encounter

This diagnosis code indicates a non-burn related fluid-filled lesion on the left upper arm. These blisters are typically caused by friction, pressure, or contact with irritants, rather than heat or cold exposure. It signifies the first time this specific injury is being treated.

Apply this code for patients presenting with a newly diagnosed blister on their left upper arm that is not due to thermal injury. Examples include blisters from repetitive rubbing against clothing, a tight cast, or a localized allergic reaction. This code is appropriate for the initial evaluation and treatment of such a lesion.

• Ensure the documentation specifies "left upper arm" and confirms the non-thermal etiology.
• Verify that this is indeed the patient's first encounter for this specific blister. Subsequent encounters will require a different seventh character.
• Distinguish from thermal blisters (burns) which are coded under T20-T32.