How can I tell if I have a nail infection (paronychia)?

With acute paronychia, a crack in the nail fold or trauma to the nail is usually seen first. Then your finger and nail fold may become red, tender and swollen.

In contrast, chronic paronychia is diagnosed after 6 weeks of inflammation, and may affect several nails and may cause the nail to appear deformed.

How is a nail infection (paronychia) diagnosed?

Most often, the diagnosis is made by the appearance of the nail and the skin around it. Your doctor will decide if a culture (taking a bit of tissue from the area for lab examination) is necessary.

Last reviewed by a Cleveland Clinic medical professional on 12/28/2017.


  • American Family Physician. Paronychia Accessed 4/6/2018.
  • American Osteopathic College of Dermatology. Paronychia Nail Infection Accessed 4/6/2018.
  • Bonifaz A, Paredes V, Fierro L. Paronychia. Skinmed. 2013 Jan-Feb;11(1):14-6.

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