ICD-10-CM Code for Thumb Wart
The ICD-10-CM code for a wart on the thumb is B07.9 (Viral wart, unspecified).
Coding Specificity
For a thumb wart, you should use:
- B07.9 - This is the standard code for common viral warts (verruca vulgaris) when no further specification is needed
- The thumb location is considered part of "common warts" which typically affect the hands and fingers
Clinical Context
Warts on the thumb are caused by human papillomavirus (HPV) infection, most commonly HPV types 1,2,4,27, or 57 1. These are benign epidermal proliferations that result from keratinocyte infection and typically present as hyperkeratotic papules on the digits.
Coding Considerations
- B07.9 is the most appropriate code as it captures viral warts without requiring anatomic site specification in the ICD-10-CM system
- The diagnosis is typically clinical and straightforward - paring down the wart often reveals pinpoint bleeding from exposed capillary loops of elongated dermal papillae 1
- No additional site-specific modifier is needed for thumb location in the current ICD-10-CM coding structure
Important Caveat
While the clinical guidelines 1 provide extensive information about diagnosis and management of cutaneous warts, they do not specify ICD-10 coding. The B07.9 code is the standard administrative code used for common warts regardless of whether they appear on fingers, thumbs, or other hand locations.