Nail Infection, Bacterial (Paronychia):
Information for adults

Paronychia, commonly known as bacterial nail infection, is inflammation of the region of the finger or toe from which the nail plate originates, which is called the proximal nail fold (PNF). This inflammation may occur in the short term (acute) or may be a long-term problem or one that keeps coming back (chronic).

Acute paronychia develops along a break in the skin and is usually seen at the side of the nail. This type of nail infection is often caused by a bacterial infection but may also be caused by herpes, a type of viral infection.

Chronic paronychia occurs most often in people whose hands are constantly or often exposed to moisture. This disorder often results from contact dermatitis, a type of skin inflammation caused by exposure to chemicals that are irritating to the skin. People with chronic paronychia may have periodic, painful flare-ups. This type of nail infection may be complicated by the addition of a fungal infection, commonly due to a type of yeast called Candida, or bacterial infection, and this may lead to abnormal nail growth.