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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.
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Risk factors for paronychia include frequent hand washing and trauma to the cuticle, such as from chronic nail biting or hangnails.
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.
Risk factors include repeatedly washing hands and trauma to the cuticle such as may occur from repeated nail biting
Painful paronychia in association with a scaly, erythematous, keratotic rash (papules and plaques) 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 aka "swollen nail" may be divided as occurring suddenly, acute, or gradually, chronic.
Acute
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. 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
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 can be the result of dish washing, finger sucking, aggressively trimming the cuticles, or frequent contact with chemicals (mild alkalis, acids, etc.).
Alternatively, paronychia may be divided as follows:
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.
Antibiotics
No strong evidence has been found to recommend topical vs. oral antibiotics, and this may be physician-dependent based on experience. Antibiotics used should have S. aureus coverage. Topical antibiotics used may be a triple antibiotic ointment, bacitracin, or mupirocin. In patients failing topical treatment or more severe cases, oral antibiotics are an option; dicloxacillin or cephalexin can be used. Indications for antibiotics with anaerobic coverage include patients where a concern exists for oral inoculation; this would require the addition of clindamycin or amoxicillin-clavulanate.