Onychomycosis (tinea unguium; ICD-9 code 110.1) is a general infection of the nail unit caused by fungal microorganisms, with dermatophytes being responsible for more than 90% of reported cases in the United States.

Managed care organizations may require one or more of the following conditions to ensure the reimbursement of therapy for onychomycosis:

	pain of foot/limb (729.5)
	paronychia of toe (681.11)
	paronychia of finger (681.02)
	peripheral vascular disease or claudication (443.9)
	difficulty walking (719.77)
	dystrophic nail or onycholysis (703.8)

Please see specific guidelines of individual managed care plans.