• Clinical science

Finger infections

Summary

Common finger infections include paronychia, felon, and herpetic whitlow. A paronychia is an acute or chronic soft tissue infection around the nail body. Acute infections are typically bacterial in origin and usually occur after minor trauma. Chronic paronychia infections have a multifactorial etiology, often related to repeated exposure to moist environments and/or skin irritants, and may be accompanied by secondary fungal infection. The diagnosis of paronychia is based on clinical signs of inflammation. A bacterial culture or fungal stain can confirm the causative pathogen. Treatment of acute paronychia usually involves antibiotics, while chronic paronychia is treated with topical steroids and antifungal therapy. Complications include nail dystrophy or felon.

Felon is an infection of the distal pulp space of the fingertip. While the cause is often unknown, minor trauma most commonly precedes infection. It is a clinical diagnosis based on the presence of local pain, swelling, induration, and erythema. Early stages of felon may be managed conservatively with analgesics and antibiotics. Later stages require incision and drainage. Complications include fingertip soft tissue necrosis and osteomyelitis.

Herpetic whitlow is discussed in herpes simplex virus infections.

Paronychia

  • Definition: soft tissue infection around a fingernail
  • Epidemiology
    • Most common hand infection in the United States
    • Sex: > (3:1)
Acute Chronic
Etiology
  • Multifactorial: chronic exposure to moist environments or skin irritants (e.g., household chemicals) eczematous inflammatory reaction → possible secondary fungal infection
Clinical features
  • Chronic or episodic history > 6 weeks of inflamed nail folds without fluctuance
  • May progress to thick, discolored nail plates → separation of cuticles/nail folds from the nail plate
Diagnosis
Treatment
Complications

References:[1][2][3][4]

Felon

References:[5][6]

Blistering distal dactylitis

References:[7]