Acute Paronychia

ByChris G. Adigun, MD, Dermatology & Laser Center of Chapel Hill
Reviewed/Revised Dec 2021 | Modified Sep 2022
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Acute paronychia is a bacterial infection of the nail fold.

In acute paronychia, bacteria (usually Staphylococcus aureus or streptococci) enter through a break in the skin resulting from a hangnail, trauma to a nail fold (the fold of hard skin at the sides of the nail plate where the nail and skin meet), loss of the cuticle (the skin at the base of the nail), or chronic irritation (such as that caused by water and detergents). Acute paronychia on the fingers is more common among people who bite or suck their fingers. In toes, infection often begins at an ingrown toenail

Paronychia is usually acute, but chronic paronychia can occur.

Acute paronychia develops along the nail margin (the sides and base of the nail fold). Over the course of hours to days, people with acute paronychia develop pain, warmth, redness, and swelling. Pus usually accumulates under the skin along the nail margin and sometimes beneath the nail. Rarely, infection penetrates deep into the finger or toe and can threaten the digit or, in extreme cases, the arm or leg. These deeper infections mainly occur in people who have diabetes or other disorders that cause poor circulation.

Acute Paronychia on the Finger
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In this photo, signs of acute paronychia include redness, mainly on one side of the finger just behind the nail, and pus on the other side.
DR. P. MARAZZI/SCIENCE PHOTO LIBRARY

The doctor makes the diagnosis of acute paronychia by examining the affected finger or toe.

Treatment of Acute Paronychia

  • Antibiotics

  • Drainage of pus

Drugs Mentioned In This Article

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