Paronychia is inflammation of the periungual folds. Acute paronychia is a rapid-onset bacterial infection (usually Staphylococcus aureus; occasionally streptococci or oral anaerobes in nail-biters) presenting with painful erythema, swelling, and possible abscess. Chronic paronychia is a multifactorial irritant/allergic dermatitis of the nail folds with secondary Candida/bacterial colonization, most often in wet-workers, presenting with swollen, erythematous, retracted cuticles and nail dystrophy. Management centers on incision and drainage for abscesses (acute), targeted antimicrobials when indicated, and for chronic paronychia, aggressive irritant avoidance with topical anti-inflammatories and barrier repair; antifungals are adjunctive rather than curative.
Epidemiology and Risk Factors
- Acute: nail biting, manicure trauma, hangnails, artificial nails.
- Chronic: repeated wet work (dishwashers, healthcare), detergents/solvents, contact allergens (acrylates), atopic dermatitis, diabetes.
Clinical Features
- Acute: throbbing pain, erythema, edema of proximal/lateral nail folds; fluctuant abscess may form; green discoloration with Pseudomonas; felon/tenosynovitis are complications.
- Chronic: eponychium loss, rounded/retracted cuticle, boggy nail folds, intermittent tenderness; nail changes (ridging, Beau lines, onycholysis).
Differential Diagnosis
- Herpetic whitlow (grouped vesicles, burning pain; avoid incision), glomus tumor (chronic pain), psoriasis/eczema of nail folds, pyogenic granuloma, periungual warts, squamous cell carcinoma or melanoma (rare persistent lesions).
Diagnosis
- Clinical. Culture pus if severe, recurrent, or unusual. KOH/culture less useful in chronic disease where Candida is colonizer.
- Patch testing for refractory chronic paronychia to identify allergens (e.g., acrylates, fragrances, nickel, rubber accelerators).
Management
- Acute Paronychia
- Early/mild without abscess: warm soaks 3–4 times/day (Burow’s solution or saline), topical antibiotics (mupirocin) ± topical steroids for inflammation.
- Abscess: incision and drainage (I&D) is primary therapy; lift eponychial fold with blunt instrument or needle; partial nail plate elevation if subungual collection.
- Systemic antibiotics:
- Indications: surrounding cellulitis, lymphangitis, severe infection, immunocompromised, systemic symptoms, or failure of I&D alone.
- Choices: anti-staphylococcal agents (cephalexin, dicloxacillin); if MRSA risk: doxycycline, TMP-SMX, clindamycin.
- Nail-biters/oral source: add anaerobic coverage (amoxicillin–clavulanate; clindamycin if allergic).
- Pseudomonas (“green nail”): acetic acid soaks; topical fluoroquinolone; systemic ciprofloxacin for severe cases.
- Chronic Paronychia
- Cornerstones: eliminate wet exposure and irritants, restore barrier, reduce inflammation.
- Keep hands dry; cotton liners under occlusive gloves; minimize immersion; apply thick barrier creams/ointments after each wash and at bedtime.
- Avoid cuticle manipulation; discontinue artificial nails until remission.
- Pharmacologic:
- Topical mid- to high-potency corticosteroids to nail folds 2–4 weeks, then taper; calcineurin inhibitors (tacrolimus 0.1% ointment) for maintenance and steroid-sparing.
- Antifungals (e.g., topical azoles; short courses of oral fluconazole/itraconazole) only if clear candidal overgrowth or secondary onychomycosis; not sole therapy.
- Refractory cases:
- Investigate allergens with patch testing and modify exposures.
- Consider intralesional triamcinolone for markedly inflamed folds.
- Surgical eponychial marsupialization or en bloc excision for persistent recalcitrant disease.
- Special Situations
- Herpetic whitlow: confirm clinically or with PCR; treat with oral acyclovir/valacyclovir within 48 hours; DO NOT incise.
- Pediatric patients: emphasize behavior modification (thumb-sucking, nail-biting).
- Diabetics/immunosuppressed: lower threshold for antibiotics; close follow-up.
Prevention and Counseling
- Regular moisturization and barrier protection.
- Proper manicure technique: avoid cutting/pushing cuticles; sterilize instruments.
- Educate on early signs to prevent abscess formation.
References (recent guidelines and reviews)
- Evidence-based management of acute and chronic paronychia, 2021–2024.
- Studies distinguishing chronic paronychia as eczematous dermatitis rather than candidiasis, 2021–2023.
- Hand dermatitis and patch testing guidance, 2022–2024.