Paronychia is a nail infection that is an often tender bacterial or fungal infection of the hand or foot, where the nail and skin meet at the side or the base of a finger or toenail. The infection can start suddenly or gradually. Paronychia is commonly misapplied as a synonym for whitlow or felon. The term is from παρωνυχία from para, "around", onyx, "nail" and the abstract nounsuffix .
Signs and symptoms
The skin typically presents as red, itchy, and hot, along with intense pain. Pus is usually present, along with gradual thickening and browning discoloration of the nail plate.
Cause
Acute paronychia is usually caused by bacteria. Paronychia is often treated with antibiotics, either topical or oral 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. In the context of bartending, it is known as bar rot. Prosector's paronychia is a primary inoculation of tuberculosis of the skin and nails, named after its association with prosectors, who prepare specimens for dissection. Paronychia around the entire nail is sometimes referred to as runaround paronychia. Painful paronychia in association with a scaly, erythematous, keratotic rash of the ears, nose, fingers, and toes may be indicative of acrokeratosis paraneoplastica, which is associated with squamous cell carcinoma of the larynx. Paronychia can occur with diabetes, drug-induced immunosuppression, or systemic diseases such as pemphigus.
Diagnosis
Types
Paronychia may be divided as follows:
Acute paronychia is an infection of the folds of tissue surrounding the nail of a finger or, less commonly, a toe, lasting less than six weeks. The infection generally starts in the paronychium at the side of the nail, with local redness, swelling, and pain. Acute paronychia is usually caused by direct or indirect trauma to the cuticle or nail fold, and may be from relatively minor events, such as dishwashing, an injury from a splinter or thorn, nail biting, biting or picking at a hangnail, finger sucking, an ingrown nail, or manicure procedures.
Chronic paronychia is an infection of the folds of tissue surrounding the nail of a finger or, less commonly, a toe, lasting more than six weeks. It is a nail disease prevalent in individuals whose hands or feet are subject to moist local environments, and is often due to contact dermatitis. In chronic paronychia, the cuticle separates from the nail plate, leaving the region between the proximal nail fold and the nail plate vulnerable to infection. It can be the result of dish washing, finger sucking, aggressively trimming the cuticles, or frequent contact with chemicals.
Alternatively, paronychia may be divided as follows:
Candidal paronychia is an inflammation of the nail fold produced by Candida albicans.
Pyogenic paronychia is an inflammation of the folds of skin surrounding the nail caused by bacteria. Generally acute paronychia is a pyogenic paronychia as it is usually caused by a bacterial infection.
Treatment
When no pus is present, warm soaks for acute paronychia are reasonable, even though there is a lack of evidence to support its use. A simple treatment with over-the-counter topical antibiotics such as mupirocin , gentamicin, bacitracin/neomycin/polymyxin B may suffice for mild cases. Antibiotics such as clindamycin or cephalexin are also often used, the first being more effective in areas where MRSA is common. If there are signs of an abscess drainage is recommended. Chronic paronychia is treated by avoiding whatever is causing it, a topical antifungal, and a topical steroid. In those who do not improve following these measures, oral antifungals and steroids may be used or the nail fold may be removed surgically.
