What is the treatment for periungual infections?

Treatment of Periungual Infections

For periungual infections, the recommended first-line treatment is topical povidone iodine 2% combined with topical antibiotics and corticosteroids, with oral antibiotics added for more severe cases. 1

Classification and Treatment Algorithm

Grade 1 (Mild) Periungual Infection

• Characterized by nail fold edema or erythema with disruption of the cuticle 1
• Treatment:
  • Continue current dose of any ongoing medications and monitor for changes in severity 1
  • Apply topical povidone iodine 2% twice daily 1
  • Apply topical antibiotics/corticosteroid combination 1
  • Reassess after 2 weeks; if worsening or no improvement, proceed to next step 1

Grade 2 (Moderate) Periungual Infection

• Characterized by nail fold edema or erythema with pain, discharge, or nail plate separation 1
• Treatment:
  • Continue current dose of any ongoing medications and monitor for changes 1
  • Obtain bacterial/viral/fungal cultures if infection is suspected 1
  • Apply topical povidone iodine 2% 1
  • Apply topical beta-blocking agents (such as timolol 0.5% gel) 1
  • Apply topical antibiotics and corticosteroids 1
  • ADD oral antibiotics (specific choice based on suspected pathogen) 1
  • Reassess after 2 weeks; if worsening or no improvement, proceed to next step 1

Grade 3 (Severe) Periungual Infection or Intolerable Grade 2

• Characterized by need for surgical intervention or antibiotics, limiting self-care activities 1
• Treatment:
  • Interrupt any causative medications until improvement to Grade 0/1 1
  • Obtain bacterial/viral/fungal cultures 1
  • Apply topical povidone iodine 2% 1
  • Apply topical beta-blocking agents 1
  • Apply topical antibiotics and corticosteroids 1
  • Administer oral antibiotics 1
  • Consider partial nail avulsion for severe cases 1
  • Reassess after 2 weeks; if worsening or no improvement, consider dose interruption or discontinuation of any causative medications 1

Antibiotic Selection

For Suspected Staphylococcal Infection (Most Common)

• Oral options:
  • Dicloxacillin or cloxacillin 1
  • Cephalexin 1
  • For MRSA: Trimethoprim-sulfamethoxazole, doxycycline, or clindamycin 1

For Mixed Bacterial Infections

• Amoxicillin-clavulanate (covers both gram-positive and many gram-negative organisms) 1
• For severe infections: consider combination therapy based on culture results 1

Special Considerations

Prevention of Periungual Infections

• Gentle skin care instructions 1
• Preventive correction of nail curvature (podiatrist referral if needed) 1
• Avoid repeated friction, trauma, and excessive pressure 1
• Wear gloves while cleaning 1
• Avoid biting nails or cutting nails too short 1
• Use antimicrobial soaks and cleansers 1
• Regular nail trimming (straight across, not too short) 1
• Daily application of topical emollients to cuticles and periungual tissues 1
• Wear comfortable, well-fitting shoes and cotton socks 1

Secondary Infections

• Secondary bacterial or mycological superinfections are present in up to 25% of periungual infections 1
• Both gram-positive and gram-negative organisms can be involved 1
• Staphylococcus species (including S. lugdunensis) are common causative agents 2
• Culture-guided therapy is important for recalcitrant cases 1

Pitfalls and Caveats

• Periungual infections can be mistaken for other conditions such as periungual verrucae, pyoderma gangrenosum, or ungual scabies 3, 4, 5
• Persistent or recurrent infections may require investigation for underlying causes 1
• Failure to treat adequately may lead to nail loss or permanent nail damage 3
• Avoid aggressive surgical debridement without appropriate antibiotic coverage 1
• For patients on anticancer agents (particularly EGFR inhibitors), periungual infections are a common adverse effect requiring prompt treatment 1