Infections of the hand
Hand infections range from paronychia and purulent abscess to limb-threatening necrotizing fasciitis, are diagnosed by anatomic pattern and bite or wound history, and are managed by prompt incision and drainage or debridement plus empiric antibiotics targeting staphylococci, streptococci, and bite-specific organisms.
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What this article covers
- Overview
Hand infections span a spectrum from a localized nail-fold infection to a limb- and life-threatening necrotizing process, and the anatomic pattern of presentation (nail fold, pulp space, flexor…
- Epidemiology
Purulent infections are typically staphylococcal: acute paronychia is most commonly caused by Staphylococcus aureus.
- Risk factors
Trauma or chronic maceration leading to an incompetent cuticle: the precipitating factor for paronychia; frequent hand immersion in water drives the chronic form.
- Pathophysiology
Paronychia is infection of the nail fold following trauma or maceration that breaches the cuticle, most often with Staphylococcus aureus in the acute form.
- Clinical features
Paronychia: tender, erythematous nail fold swelling, typically a single nail in the acute form; chronic paronychia is more insidious, involves multiple fingers, with missing or dystrophic cuticles and nail ridging.
- Differential diagnosis
Necrotizing fasciitis: pain out of proportion to exam, hemorrhagic bullae, and crepitus, unlike the more indolent course of simple cellulitis or an abscess.
- Diagnosis
Most localized hand infections (paronychia, felon, abscess, herpetic whitlow) are diagnosed clinically by anatomic pattern and appearance, without routine culture or imaging; necrotizing fasciitis is…
- Management
First, irrigate and assess every hand wound, characterizing extent, depth, and neurovascular involvement, and obtain surgical evaluation for debridement or foreign body removal, particularly for any…
- Complications
Flexor tenosynovitis progressing to tendon necrosis and permanent loss of digit function if drainage is delayed.
- Prognosis
Localized purulent infections resolve promptly with drainage and appropriate antibiotics in the great majority of patients.
- Prevention
Prompt irrigation with sterile normal saline and wound assessment for every hand bite or puncture wound, as soon as possible after injury.
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