What is the treatment for a child with a finger infection?

Treatment of Infected Finger in a Child

For a child with a finger infection, start with incision and drainage if an abscess is present, combined with oral antibiotics targeting Staphylococcus aureus and Streptococcus pyogenes—specifically oral amoxicillin-clavulanate as first-line therapy, or clindamycin if MRSA is suspected or in penicillin-allergic patients. 1

Initial Assessment and Classification

The first critical step is determining whether this is a superficial or deep infection 2:

• Superficial infections (cellulitis, paronychia, minor abscesses) involve skin and subcutaneous tissues
• Deep infections (felon, pyogenic flexor tenosynovitis, septic arthritis) involve tendon sheaths, joint spaces, or bone 2

Red flags requiring immediate surgical consultation include 1, 2:

• Severe pain disproportionate to clinical findings
• Inability to flex the finger (suggests flexor tenosynovitis)
• Fusiform swelling of the entire finger
• Pain with passive extension of the finger
• Tenderness along the flexor tendon sheath
• Systemic toxicity or fever

Treatment Algorithm by Infection Type

Superficial Infections (Cellulitis, Minor Paronychia)

For simple cellulitis without purulence:

• Oral amoxicillin-clavulanate is the preferred first-line agent, covering both streptococci and common staphylococci 1
• Dosing: 45 mg/kg/day divided every 12 hours (or 40 mg/kg/day divided every 8 hours for higher-dose formulations) 3
• Duration: 5-10 days 1

If MRSA is suspected (purulent drainage, previous MRSA infection, or local resistance patterns):

• Clindamycin 10-13 mg/kg/dose every 6-8 hours (maximum 40 mg/kg/day) 1, 4
• Alternative: TMP-SMX (if child >2 months old), though this requires addition of a beta-lactam for streptococcal coverage 1
• Do not use tetracyclines in children <8 years of age 1

Abscess or Felon

Incision and drainage is the primary treatment 1, 2:

• Surgical drainage is essential and often sufficient for small abscesses 1
• Add antibiotics if: surrounding cellulitis present, systemic signs, immunocompromised, or failed drainage alone 1

Antibiotic selection after drainage:

• Same regimen as above: amoxicillin-clavulanate or clindamycin 1
• For hospitalized children with complicated infection: IV vancomycin 15 mg/kg/dose every 6 hours, or IV clindamycin if local MRSA resistance <10% 1

Paronychia

Acute paronychia:

• Warm soaks and elevation 2
• If abscess present: incision and drainage 2
• Topical antibiotics (mupirocin 2% ointment) for minor infections 1
• Oral antibiotics (amoxicillin-clavulanate or clindamycin) if cellulitis extends beyond nail fold 1

Deep Space Infections (Pyogenic Flexor Tenosynovitis, Septic Arthritis)

These require immediate surgical consultation and IV antibiotics 1, 2:

• IV vancomycin is recommended for empiric coverage 1
• If patient is stable without bacteremia and local clindamycin resistance is low (<10%): IV clindamycin 10-13 mg/kg/dose every 6-8 hours 1
• Alternative: IV cefazolin 33 mg/kg/dose every 8 hours (if MRSA not suspected) 1
• Duration: minimum 3-4 weeks for septic arthritis, 4-6 weeks for osteomyelitis 1

Adjunctive Measures

All finger infections benefit from 2:

• Elevation of the affected hand above heart level
• Splinting in position of function (slight flexion at all joints)
• Warm soaks 3-4 times daily
• Analgesics as needed

Special Considerations

Animal or human bite wounds require broader coverage 1:

• Amoxicillin-clavulanate is the drug of choice, covering oral flora including Pasteurella multocida and anaerobes 1
• Ensure tetanus prophylaxis is up to date 1

Herpetic whitlow (vesicular lesions, often in thumb-sucking children):

• This is viral (HSV) and does not require antibiotics 2
• Avoid incision and drainage, which can worsen infection 2

Common Pitfalls

• Never delay surgical consultation for suspected deep infections—these progress rapidly and can cause permanent disability 2
• Avoid monotherapy with TMP-SMX without adding beta-lactam coverage, as it lacks activity against streptococci 1
• Do not use topical bacitracin alone for anything beyond the most superficial wounds—it has insufficient coverage 5
• Ensure proper dosing of amoxicillin-clavulanate based on the amoxicillin component, not the total tablet weight 3
• Take cultures before starting antibiotics in moderate-to-severe infections to guide therapy if initial treatment fails 1

When to Hospitalize

Admit for IV antibiotics and possible surgery if 1, 2:

• Deep space infection suspected
• Systemic toxicity (fever, tachycardia, altered mental status)
• Failed outpatient management after 48-72 hours
• Immunocompromised patient
• Inability to comply with outpatient treatment
• Age <3 months with any bacterial infection