ICD-10 Code for Infected Abscess of Left Lower Leg - Initial Encounter
The appropriate ICD-10-CM code for an initial encounter of an infected abscess on the left lower leg is L02.416 (Cutaneous abscess of left lower limb).
Code Structure and Specificity
The ICD-10-CM system provides significantly enhanced specificity compared to ICD-9-CM, particularly for wound location and laterality 1. For lower limb infections:
- L02.416 specifically captures:
- L02 = Cutaneous abscess, furuncle and carbuncle
- 41 = Lower limb location
- 6 = Left side laterality
- The 7th character extension would be added for encounter type (A for initial encounter)
Clinical Context for Coding
When documenting an infected abscess of the lower leg, the clinical diagnosis should be based on the presence of 2:
At least two signs of inflammation:
- Local swelling or induration
- Erythema >0.5 cm around the wound
- Local tenderness or pain
- Local warmth
- Purulent discharge
Abscess-specific findings requiring urgent surgical consultation 2:
- Deep abscess formation
- Fluctuance on examination
- Collection of purulent material
Important Coding Considerations
Laterality is mandatory in ICD-10-CM and must be documented 1. The ICD-10 system captures 96% of incident lower limb ulcers compared to only 85% with ICD-9, with particular improvement in capturing heel and midfoot locations 1.
Additional codes may be required if the patient has 2:
- Underlying diabetes mellitus (E08-E13 series)
- Peripheral arterial disease
- Systemic inflammatory response (R65 series if present)
Verification and Accuracy
When using ICD-10 codes for infection documentation, verification against medical records is essential 3. Non-verified complication codes can significantly overestimate infection rates, with verification improving accuracy from 47.4% to 20.1% confirmed complications in surgical admissions 3.
The positive predictive value for ICD-10-CM infection codes in patients requiring treatment is approximately 80% when properly validated 4, making accurate clinical documentation critical for appropriate code assignment.