SIGNS AND SYMPTOMS 
- Paronychia:
- Localized edema, erythema, and pain in proximal portion of lateral nail fold
- Fluctuance may be present and may extend beneath the nail margin.
- Systemic signs and symptoms are usually not present.
- Felon:
- Erythema and tense swelling of the distal pulp space that does not extend proximal to the proximal interphalangeal (PIP) joint
- Aching pain early, severe throbbing pain late
- Systemic signs are usually not present.
- Herpetic whitlow:
- Distal pulp space is swollen, but remains soft.
- Lateral nail folds may be affected.
- Throbbing pain of the distal pulp space
- Vesicles containing nonpurulent fluid are present and may form bullae.
- Systemic symptoms may be present:
- Flexor tenosynovitis:
- Kanavel signs:
- Severe pain and symmetric edema of the digit
- Tenderness over the course of tendon sheath
- Flexed position of the finger at rest
- Pain on passive extension of the finger—may be the only finding in early infection
- Clenched fist injury:
- Laceration over the metacarpophalangeal (MCP) joint from striking an object with a clenched fist
- Any laceration over the MCP must be assumed to be a human bite wound until proven otherwise.
- Web space abscess:
- Pain and edema of the affected web space and adjacent palm
- Fingers are held abducted.
- Palmar space infections:
- Thenar space infection:
- Pain, tenderness, tense edema of thenar eminence
- Dorsal edema without tenderness
- Thumb is held abducted and flexed, and passive adduction is painful.
- Midpalmar space infection:
- Pain, edema, and tenderness of the midpalmar space
- Dorsal edema without tenderness
- Motion of middle and ring fingers is painful
- Hypothenar space infection:
- Pain and fullness over hypothenar eminence
- No limitation of finger movement
History
See Signs and Symptoms.
Physical Exam
See Signs and Symptoms.
ESSENTIAL WORKUP
Most hand infections are diagnosed by history and physical exam with special attention to neurovascular status.
DIAGNOSIS TESTS & INTERPRETATION
Lab
- Although usually not necessary, herpetic whitlow may be confirmed by Tzanck test.
- Gram stain and culture may guide antibiotic choice in felons.
- Blood cultures, CBC are not routinely indicated.
Imaging
- Radiographs are usually not helpful unless there has been trauma or a suspected foreign body.
- With felon, flexor tenosynovitis, and palmar space infection, radiograph may identify osteomyelitis or foreign body.
- Radiographs in clenched fist injury may reveal a fracture.
DIFFERENTIAL DIAGNOSIS
- Paronychia should be differentiated from herpetic whitlow and felon.
- The differential for palmar space infection includes flexor tenosynovitis, cellulitis, and web space infection.
[Outline]
PRE-HOSPITAL
Hand immobilization as appropriate
ED TREATMENT/PROCEDURES
- Paronychia:
- Early paronychia/simple cellulitis without purulence present may be managed with oral antibiotics and rest:
- Superficial infections are drained by inserting a No. 11 blade between nail and eponychium, and lifting the eponychium from the nail.
- If necessary, the lateral nail fold may be incised tangential to the curvature of the nail.
- When pus is present under the adjacent nail, 1/4 of the nail should be removed.
- When pus is present under the dorsal roof of the proximal nail, remove 1/3 of the proximal nail.
- Felon:
- A lateral incision avoiding the neurovascular bundle is preferred.
- More extensive felons are drained through a unilateral longitudinal incision that does not cross the distal interphalangeal (DIP) flexor crease.
- Disruption of fibrous septa is no longer recommended:
- Results in an unstable fingertip
- Loculations may need to be broken up.
- Give oral antibiotics to cover skin pathogens, place a drain, and recheck in 48 hr:
- Cephalexin, dicloxacillin
- Herpetic whitlow:
- Usually self-limited; do not incise and drain.
- Oral acyclovir may be given to patients with systemic involvement.
- Flexor tenosynovitis, web space abscess, palmar space infection:
- Elevation, IV antibiotics, and pain control:
- All of these infections require immediate consultation with a hand surgeon.
- Clenched fist injury:
- Elevation, IV antibiotics, tetanus prophylaxis, and pain control in the ED:
- Ampicillin/sulbactam, cefoxitin, ticarcillin/clavulanate
- All bite wounds with evidence of infection or joint involvement require emergent consultation with a hand surgeon.
- If there are no signs of infection and no joint penetration, patients may be considered for outpatient treatment with oral antibiotics after appropriate irrigation and wound care:
- Ampicillin/clavulanate or penicillin V + cephalexin or dicloxacillin
- Do not primarily close lacerations associated with a human bite; delayed primary closure or healing by secondary intention is appropriate.
MEDICATION
- Acyclovir: 400 mg PO TID for 10 days (peds: Not recommended for herpetic whitlow)
- Amoxicillin/clavulanate: 875/125 mg PO BID (peds: 40 mg/kg/d PO div. q6h)
- Ampicillin/sulbactam: 1.5–3 g IV q6h (peds: Safety not established)
- Cefoxitin: 2 g IV q8h (peds: 80–160 mg/kg/d IV or IM div. q6h)
- Cephalexin: 500 g PO QID for 7 days (peds: 40 mg/kg/d PO div. q6h)
- Clindamycin: 300–450 mg PO QID for 7 days. Can use IV in severe cases: 600–900 mg IV q8h (peds: 20–40 mg/kg/d div. q8h PO IV or IM)
- Dicloxacillin: 500 mg PO QID for 7 days (peds: 12.5–50 mg/kg/d PO div. q6h)
- Erythromycin: 500 mg PO QID for 7 days (peds: 40 mg/kg/d div. q6h PO)
- Penicillin V: 250 mg PO QID (peds: 40 mg/kg/d PO div. q6h)
- Ticarcillin/clavulanate: 3.1 g IV q4–q6h (peds: 150–300 mg/kg/d IV div. q6–8h)
First Line
Tailor to etiology
Second Line
Tailor to etiology
[Outline]
DISPOSITION
Admission Criteria
- Flexor tenosynovitis, web space abscess, palmar space infections:
- All these infections require admission for IV antibiotics and drainage.
- Clenched fist injury with signs of infection:
- Requires admission for surgical débridement and IV antimicrobials
Discharge Criteria
- Paronychia and felons:
- Patients with uncomplicated paronychia or felon may be discharged from the ED with a recheck and drain removal in 48 hr.
- Herpetic whitlow:
- Patients with herpetic whitlow may be discharged from the ED with appropriate follow-up.
- Clenched fist injury without infection:
- May be discharged on oral antibiotics with follow-up in 24 hr
Issues for Referral
Immediate consultation in emergency department is indicated
FOLLOW-UP RECOMMENDATIONS
Usually arranged by admitting physician after operative therapy
[Outline]
- Antosia RE, Lyn E. The hand. In: Rosen P, et al., eds. Emergency Medicine: Concepts and Clinical Practice. 4th ed. St. Louis, MO: Mosby, 1997;1998:625–668.
- Bach HG, Steffin B, Chhadia AM, et al. Community-associated methicillin-resistant Staphylococcus aureus hand infections in an urban setting. J Hand Surg Am. 2007;32(3):380–383.
- Ong YS, Levin LS. Hand infections. Plast Reconstr Surg. 2009;124(4):225e–233e.
See Also (Topic, Algorithm, Electronic Media Element)
Hand Infections http://emedicine.medscape.com/article/783011-overview