Is mupirocin effective against Hemophilus influenzae infections?

Mupirocin is Not Effective Against Haemophilus influenzae Infections

Mupirocin is not effective for treating Haemophilus influenzae infections and should not be used for this purpose. While mupirocin has excellent activity against staphylococci and streptococci, it has limited effectiveness against Gram-negative bacteria like H. influenzae in clinical practice.

Antimicrobial Spectrum of Mupirocin

Mupirocin's clinical utility is primarily for:

• Staphylococcus aureus (including MRSA)
• Staphylococcus epidermidis
• Streptococcus species
• Localized skin infections like impetigo 1

Despite some early in vitro studies suggesting potential activity against H. influenzae 2, this has not translated to clinical effectiveness for H. influenzae infections.

Recommended Treatments for H. influenzae Infections

For H. influenzae infections, the following treatments are recommended instead:

For Non-Severe H. influenzae Respiratory Infections:

• First-line: Amoxicillin-clavulanate, cefpodoxime, cefprozil, or cefuroxime 3
• Alternative: Respiratory fluoroquinolones (levofloxacin, moxifloxacin) 3

For Severe H. influenzae Infections:

• Cefotaxime, ceftriaxone, or cefuroxime IV 3
• These agents also eradicate H. influenzae colonization 3

For Prophylaxis After H. influenzae Type b Exposure:

• Rifampin is recommended for chemoprophylaxis as it achieves high concentrations in respiratory secretions and eradicates nasopharyngeal carriage in >95% of carriers 3

Antibiotic Resistance Considerations

H. influenzae has shown increasing resistance patterns that further limit treatment options:

• Many strains produce beta-lactamase, making them resistant to ampicillin 4
• Resistance to tetracycline, kanamycin, and chloramphenicol has also been documented 4

Clinical Applications of Mupirocin

Mupirocin's appropriate uses include:

1. Treatment of impetigo and other localized skin infections caused by susceptible organisms 1, 5
2. Eradication of nasal carriage of Staphylococcus aureus, including MRSA 3, 6
3. Prevention of recurrent staphylococcal skin infections when used as part of a decolonization strategy 3

Important Considerations When Using Mupirocin

• Complete the full 5-7 day course of treatment even if improvement occurs earlier 1
• Limit use to short courses to prevent development of resistance 3
• Mupirocin resistance has been reported in some community settings 3
• Some mupirocin formulations contain natural rubber latex, which may cause allergic reactions in latex-sensitive individuals 3

In conclusion, while mupirocin has an important role in treating staphylococcal and streptococcal skin infections, it should not be used for H. influenzae infections. For H. influenzae infections, appropriate antibiotics include beta-lactams with beta-lactamase inhibitors, cephalosporins, or fluoroquinolones depending on the severity and site of infection.