Paronychia

Background

• Inflammation/infection of the proximal or lateral nail folds
• Usually caused by direct or indirect minor trauma (e.g. nail-biting, manicures, hangnails, ingrown nail, dishwashing)
  • Trauma allows entry of bacteria
  • S. aureus is most common, although S. pyogenes, Pseudomonas pyocyanea, and Proteus vulgaris are also common

Paronychia of middle digit

Clinical Features

• Rapid onset of erythema, edema, and pain of proximal or lateral nail folds
• Usually only affects one nail
• May see purulent drainage (expressed with pressure on nail)

Differential Diagnosis

Hand and finger infections

• Bed bugs
• Closed fist infection (Fight Bite)
• Hand cellulitis
• Hand deep space infection
• Hand-foot-and-mouth disease
• Herpetic whitlow
• Felon
• Flexor tenosynovitis
• Paronychia
• Scabies
• Sporotrichosis

Look-Alikes

• Digital mixoid cyst

Diagnosis

• Clinical diagnosis, based on history of minor trauma and physical examination
• If unclear if wound is fluctuant:
  • Have pt apply pressure to distal aspect of affected digit
  • A larger than expected area of blanching, reflecting a collection of pus, may identify need for drainage

Treatment

Acute

• More likely to be bacterial
• If no fluctuance is identified:
  • Warm compresses, soaks, elevation
  • Antibiotic ointment TID x5-10 days (mild cases) ± topical steroid
  • PO Antibiotics (more severe or persistent cases)
    • Augmentin BID x7 days OR
    • Clindamycin 150-450mg TID or QID x7 days OR
    • TMP-SMX DS 1-2 tab PO BID x7 days
• If fluctuance or purulence is identified:
  • Consider soaking hand for preparation
  • Consider digital block
  • Incise area of greatest fluctuance
    • Incise parallel to nail (do NOT incise perpendicular to fluctulance)
    • Use iris scissors, flat tweezers, or #11 blade

Chronic

• Multifactorial inflammation due to persistent irritation - may also have fungal component
• Mainstay of therapy is avoidance of irritant
• Consider topical antifungals vs Diflucan 150mg po qweek x 4-6 weeks

Disposition

• Discharge

See Also

• Hand and finger infections