Do you have green toenail discoloration?

Green toenail discoloration is also called green nail syndrome.  This results from a pseudomonas infection. 

Predisposing factors for green nail syndrome:

1. Tinea infection of the nails (because it alters the nail plate making the nailbed more susceptible to pathogens)
2. Infection of the skin around the nails.
3. Working as a barber, dishwasher, janitor, baker, or nail salon (because of water and chemical exposures)
4. Use of artificial nails and nail polishes

Do you need additional testing to confirm the diagnosis?  It is a clinical diagnosis.  No labs are needed to confirm the diagnosis.

What is the treatment?  Trim the nails. Keep nails dry.  Avoid trauma to the toe.  Home treatments like vinegar soaks or diluted chlorine bleach are not known to be effective.  Topical antibiotics can be applied to the nail bed. Occasionally the nail needs to be removed.  Oral antibiotics can be used for severe infections.