Paronychia is an inflammation of the skin around the nail, often due to bacteria or fungi.
Its sudden (acute) occurrence is usually due to the bacterium Staphylococcus aureus. Gradual (chronic) occurrences are typically caused by fungi, commonly Candida albicans.
Risk factors for paronychia include frequent hand washing and trauma to the cuticle, such as from chronic nail biting or hangnails.
Treatment typically involves antibiotics for bacterial infections and antifungals for fungal infections. If there is pus formation, incision and drainage may be necessary.
Paronychia is commonly mistakenly used interchangeably with herpetic whitlow or felon, which are distinct conditions.
Etymology
The term paronychia is from the Greek: παρωνυχία (παρά, para, 'around'; ὄνυξ, onyx, 'nail'; and the noun suffix -ia).
Signs and symptoms
The index and middle fingers are most commonly affected and may present with redness, swelling and pain. Pus or discharge may be present.
An infection of the cuticle secondary to a splinter
Left and right ring fingers of the same person: The distal phalanx of the finger on the right exhibits swelling due to acute paronychia.
Chronic paronychia
Causes
Acute paronychia is usually caused by bacteria. It is often treated with antibiotics, either topical (applied to the skin) or oral (taken by mouth), or both. Chronic paronychia is most often caused by a yeast infection of the soft tissues around the nail but can also be traced to a bacterial infection. If the infection is continuous, the cause is often fungal and needs antifungal cream or paint to be treated.
Risk factors include repeatedly washing hands and trauma to the cuticle such as may occur from repeated nail biting or hangnails. In the context of bartending, it is known as "bar rot".
Painful paronychia in association with a scaly, erythematous, keratotic rash (papules and plaques) of the ears, nose, fingers, and toes may be indicative of...
