What is the treatment for a patient with a nail infection that has purulent discharge?

Treatment of Nail Infection with Purulent Discharge

For a nail infection with purulent discharge that can be expressed, initiate oral antibiotics targeting Staphylococcus aureus and gram-positive organisms immediately, obtain bacterial cultures from the purulent material, and drain any abscess present. 1, 2

Immediate Management Steps

Culture and Drainage

• Obtain bacterial cultures from the purulent discharge before starting antibiotics to guide appropriate therapy and identify the causative organism. 1, 2
• If an abscess is present, drainage is mandatory before antibiotic therapy. 2 The ability to express green pus suggests an abscess or significant purulent collection that requires drainage. 3
• Consider partial or total nail avulsion if a subungual abscess is present, as this may be required in addition to antibiotics. 1, 2

Antibiotic Selection

First-line oral antibiotics include: 1, 2

• Cephalexin (first-generation cephalosporin) - particularly effective against Staphylococcus aureus and Streptococcus pyogenes 2
• Amoxicillin-clavulanate 1
• Clindamycin 1
• Doxycycline 1

The primary pathogens to target are Staphylococcus aureus and other gram-positive organisms. 1 Green discharge specifically may indicate Pseudomonas aeruginosa infection, which would require fluoroquinolone coverage (ciprofloxacin). 3, 4

Adjunctive Wound Care

• Apply daily dilute vinegar soaks to reduce inflammation and edema. 1
• Use mid to high potency topical steroid ointment to reduce inflammation. 1
• Keep the affected area clean and dry between soaks. 2
• Apply antiseptic hand baths with povidone-iodine 1:10 or potassium permanganate 1:10,000. 3
• Consider povidone-iodine ointment for topical application. 3

Monitoring and Follow-up

• Reassess after 2 weeks of treatment. 3, 1, 2
• If infection worsens or does not improve, consider:
  • Alternative antibiotics based on culture results 2
  • Surgical intervention for drainage 3, 2
  • Dose reduction or interruption of therapy if severe (grade 3) infection 3

Special Considerations

Green Discharge

Green or black coloration of purulent discharge strongly suggests Pseudomonas aeruginosa infection, which requires specific treatment with ciprofloxacin rather than standard gram-positive coverage. 3, 4

Severity Grading

• Moderate (grade 2): Continue antibiotics, monitor for 2 weeks, consider silver nitrate for granulation tissue, use oral antibiotics (tetracyclines if not superinfected, otherwise quinolones). 3
• Severe (grade 3): May require dose reduction, oral antibiotics based on resistance results, consider surgical intervention. 3

Common Pitfalls to Avoid

• Failing to obtain cultures before starting antibiotics can prevent identification of resistant organisms or unusual pathogens. 1, 2
• Inadequate duration of antibiotic therapy leading to recurrence - follow recommended treatment duration. 2
• Not draining an abscess before antibiotic therapy reduces treatment effectiveness. 2
• Avoiding manipulation of cuticles and nail biting to prevent further infection. 2
• Inadequate cleaning and debridement of the nail bed when nail removal is performed can lead to complications. 5