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Acute Paronychia

By

Chris G. Adigun

, MD, Dermatology & Laser Center of Chapel Hill

Last full review/revision Aug 2019| Content last modified Aug 2019
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Paronychia is infection of the periungual tissues. Acute paronychia causes redness, warmth, and pain along the nail margin. Diagnosis is by inspection. Treatment is with antistaphylococcal antibiotics and drainage of any pus.

Paronychia is usually acute, but chronic cases Chronic Paronychia Chronic paronychia is recurrent or persistent nail fold inflammation, typically of the fingers. (See also Overview of Nail Disorders.) Chronic paronychia is an inflammatory disorder of the nail... read more Chronic Paronychia occur. In acute paronychia, the causative organisms are usually Staphylococcus aureus or streptococci and, less commonly, Pseudomonas or Proteus species. Organisms enter through a break in the epidermis resulting from a hangnail, trauma to a nail fold, loss of the cuticle, or chronic irritation (eg, resulting from water and detergents). Biting or sucking the fingers can also predispose people to developing the infection. In toes, infection often begins at an ingrown toenail Ingrown Toenail An ingrown toenail is incurvation or impingement of a nail border into its adjacent nail fold, causing pain. (See also Overview of Nail Disorders.) Causes of ingrown toenail include tight shoes... read more Ingrown Toenail .

Novel drug therapies, such as with inhibitors of epidermal growth factor receptor (EGFR), mammalian target of rapamycin (mTOR), and less commonly BRAF gene inhibitors, can cause paronychia along with other skin changes. The mechanism is not completely understood. However, most cases seem to be caused by the drug itself, such as through alterations in retinoic acid metabolism, and not by secondary infection.

Symptoms and Signs of Acute Paronychia

Paronychia develops along the nail margin (lateral and/or proximal nail fold), manifesting over hours to days with pain, warmth, redness, and swelling. Pus usually develops along the nail margin and sometimes beneath the nail. Infection can spread to the fingertip pulp, causing a felon Felon A felon is an infection of the pulp space of the fingertip, usually with staphylococci and streptococci. (See also Overview and Evaluation of Hand Disorders.) The most common site is the distal... read more Felon . Rarely, infection penetrates deep into the finger, sometimes causing infectious flexor tenosynovitis Infectious Flexor Tenosynovitis Infectious flexor tenosynovitis is an acute infection within the flexor tendon sheath. Diagnosis is suggested by Kanavel signs and confirmed with x-rays. Treatment is surgical drainage and antibiotics... read more .

Diagnosis of Acute Paronychia

  • Clinical evaluation

Diagnosis of acute paronychia is by clinical evaluation.

Treatment of Acute Paronychia

  • Antibiotics effective against staphylococci and streptococci

  • Drainage of pus

Early treatment is warm compresses or soaks and an oral antibiotic effective against staphylococci and streptococci (eg, dicloxacillin or cephalexin 250 mg 4 times a day, clindamycin 300 mg 4 times a day). In areas where methicillin-resistant S. aureus is common, antibiotics that are effective against this organism (eg, trimethoprim/sulfamethoxazole) should be chosen based on results of local sensitivity testing. In patients with diabetes and others with peripheral vascular disease, toe paronychia should be monitored for signs of cellulitis Cellulitis Cellulitis is acute bacterial infection of the skin and subcutaneous tissue most often caused by streptococci or staphylococci. Symptoms and signs are pain, warmth, rapidly spreading erythema... read more Cellulitis or more severe infection (eg, extension of edema or erythema, lymphadenopathy, fever).

Fluctuant swelling or visible pus should be drained with a Freer elevator, small hemostat, or #11 scalpel blade inserted between the nail and nail fold. Skin incision is unnecessary. A thin gauze wick can be inserted for 24 to 48 hours to allow drainage.

A case caused by epidermal growth factor receptor inhibitor therapy and refractory to the usual treatments was treated successfully with autologous platelet-rich plasma.

Key Points

  • Acute paronychia can be related to a hangnail, nail fold trauma, loss of the cuticle, chronic irritation, or biting or sucking of the fingers.

  • The diagnosis is likely when severe redness, pain, and warmth develop acutely along the nail margin, but consider alternative diagnoses, particularly if treatment is unsuccessful.

  • Treat with an antibiotic and moist heat and by draining any visible pus.

Drugs Mentioned In This Article

Drug Name Select Trade
No US brand name
CLEOCIN
KEFLEX
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