Impetigo is a contagious superficial skin infection most commonly caused by Staph aureus; which topical antibiotic is commonly used?

Impetigo is a contagious superficial skin infection most commonly caused by Staph aureus; which topical antibiotic is commonly used?

• A. Mupirocin ointment
• B. Neomycin ointment
• C. Hydrocortisone cream
• D. Clindamycin oral

Answer: (A)

Impetigo is a shallow skin infection most often caused by Staphylococcus aureus, with Streptococcus pyogenes as a possible contributor. For localized, uncomplicated cases, a topical antibiotic is preferred because it delivers high concentrations directly to the infected skin with minimal systemic exposure. Mupirocin ointment is the classic topical agent for impetigo because it effectively covers the usual pathogens involved (Staph aureus and Streptococcus species) and is specifically formulated for skin use. Its action is to inhibit bacterial protein synthesis by blocking isoleucyl-tRNA synthetase, which stops bacterial growth at the site of infection. It is well tolerated and has good skin penetration with limited systemic absorption, making it ideal for treating minor, localized lesions and helping to reduce contagiousness. Other options don’t fit as well for simple topical therapy. Neomycin ointment can cause dermatitis and has variable efficacy against impetigo pathogens, making it a less reliable choice. Hydrocortisone cream is a steroid and does not treat the infection; it may reduce inflammation but can worsen infection if used alone. Clindamycin given orally is a systemic antibiotic appropriate for more extensive disease or resistant organisms, not for straightforward topical treatment. So, for uncomplicated impetigo treated topically, mupirocin ointment is the best choice.

Impetigo is a shallow skin infection most often caused by Staphylococcus aureus, with Streptococcus pyogenes as a possible contributor. For localized, uncomplicated cases, a topical antibiotic is preferred because it delivers high concentrations directly to the infected skin with minimal systemic exposure.

Mupirocin ointment is the classic topical agent for impetigo because it effectively covers the usual pathogens involved (Staph aureus and Streptococcus species) and is specifically formulated for skin use. Its action is to inhibit bacterial protein synthesis by blocking isoleucyl-tRNA synthetase, which stops bacterial growth at the site of infection. It is well tolerated and has good skin penetration with limited systemic absorption, making it ideal for treating minor, localized lesions and helping to reduce contagiousness.

Other options don’t fit as well for simple topical therapy. Neomycin ointment can cause dermatitis and has variable efficacy against impetigo pathogens, making it a less reliable choice. Hydrocortisone cream is a steroid and does not treat the infection; it may reduce inflammation but can worsen infection if used alone. Clindamycin given orally is a systemic antibiotic appropriate for more extensive disease or resistant organisms, not for straightforward topical treatment.

So, for uncomplicated impetigo treated topically, mupirocin ointment is the best choice.