ICD-10 Coding for Eczema on Hands and Feet
For eczema affecting both hands and feet, use L30.9 (Dermatitis, unspecified) as the primary code, or more specifically L20.84 (Intrinsic [allergic] eczema) if atopic features are present, with additional codes L23.9 (Allergic contact dermatitis, unspecified cause) or L24.9 (Irritant contact dermatitis, unspecified cause) if contact dermatitis is confirmed.
Primary ICD-10 Codes for Hand and Foot Eczema
Most Commonly Used Codes
L30.9 - Dermatitis, unspecified: This is the most general code when the specific type of eczema has not been definitively determined 1, 2.
L20.84 - Intrinsic (allergic) eczema: Use this when the patient has atopic features or a history of atopic dermatitis affecting the hands and feet 2, 3.
L23.9 - Allergic contact dermatitis, unspecified cause: Apply this code when patch testing confirms allergic contact dermatitis (ACD) but the specific allergen is not documented 2, 3, 4.
L24.9 - Irritant contact dermatitis, unspecified cause: Use when irritant contact dermatitis (ICD) is diagnosed, typically by exclusion of positive patch testing 2, 3.
More Specific Codes When Etiology is Known
L23.0 - Allergic contact dermatitis due to metals: Use when nickel or other metal sensitization is confirmed by patch testing, which occurs in 89% of patients reporting metal allergy 3, 4.
L23.1 - Allergic contact dermatitis due to adhesives: Apply when adhesive-related allergens are identified 4.
L23.5 - Allergic contact dermatitis due to other chemical products: Use for rubber accelerators, which have high sensitization frequency in hand eczema patients 3.
L23.7 - Allergic contact dermatitis due to plants, except food: Apply when plant-related allergens are confirmed 4.
L30.0 - Nummular dermatitis: Use for coin-shaped eczematous lesions on hands and feet 1.
L30.1 - Dyshidrosis [pompholyx]: Apply specifically for vesicular hand and foot eczema 5, 2.
Clinical Documentation Requirements for Accurate Coding
Essential Elements to Document
Location specificity: Document whether dermatitis affects palms, dorsal hands, fingers, soles, or dorsal feet, as dorsal involvement is more common in ACD, followed by ICD and atopic dermatitis 3.
Morphology: Describe whether presentation is acute (erythema, edema, vesicles), subacute (crusting, scaling), or chronic (lichenification) 6, 7.
Laterality: Note if bilateral or unilateral, as bilateral distribution suggests exposure to common irritants like hand sanitizers or cleaning products 7.
Occupational factors: Document work-related exposures, as occupationally relevant reactions occur in 18.0% of hand dermatitis cases 4.
Patch test results: When available, document specific allergens identified, as this determines whether to code as L23.x (allergic) versus L24.x (irritant) 2, 3.
Common Pitfalls in ICD-10 Coding for Hand and Foot Eczema
Avoid These Coding Errors
Do not use L20.9 (Atopic dermatitis, unspecified) for isolated hand/foot eczema without documented atopic features elsewhere, as hand eczema has diverse etiology beyond atopy 1, 8.
Do not code as L30.9 when patch testing has been performed - use the specific L23.x or L24.x codes based on results 2, 3.
Do not assume all hand eczema is occupational - only 18% of hand dermatitis has occupationally relevant reactions, compared to 8.9% for hand-foot dermatitis and 4.0% for foot dermatitis alone 4.
Do not overlook the need for multiple codes when both allergic and irritant factors coexist, which is common in chronic hand eczema 1, 8.
Algorithm for Selecting the Correct ICD-10 Code
Step 1: Determine if Patch Testing Was Performed
If patch testing positive: Use L23.x codes (allergic contact dermatitis) with specific subcategory based on identified allergen 2, 3.
If patch testing negative: Use L24.x codes (irritant contact dermatitis) 2.
If no patch testing performed: Use L30.9 (dermatitis, unspecified) or L20.84 if atopic features present 1, 2.
Step 2: Assess for Specific Clinical Patterns
If vesicular presentation on palms/soles: Consider L30.1 (dyshidrosis/pompholyx) 5, 2.
If coin-shaped lesions: Consider L30.0 (nummular dermatitis) 1.
If chronic with lichenification: Document chronicity and use appropriate L20.x or L30.x code based on etiology 6, 8.