No, discontinue the antibiotic ointment
Topical antibiotics should not be used for PEG site infections, even when cultures show Proteus mirabilis and Pseudomonas aeruginosa. The patient is already receiving appropriate systemic fluoroquinolone therapy, which is the correct treatment approach for this infection 1.
Rationale Based on Current Guidelines
The 2022 ESPEN guidelines explicitly state that "topical antibiotics should not be used" for PEG site infections 1. Instead, the recommended approach is:
- First-line treatment: Antimicrobial dressings (containing silver, iodine, or polyhexamethylene biguanide) applied topically to the entry site
- If local therapy fails: Add systemic broad-spectrum antibiotics tailored to culture results
Since your patient already has positive cultures showing Proteus mirabilis and Pseudomonas aeruginosa and is on systemic fluoroquinolone therapy, the antibiotic ointment serves no additional therapeutic purpose and should be stopped.
What to Use Instead
Replace the antibiotic ointment with antimicrobial dressings that provide sustained-release antimicrobial activity 1:
- Silver-impregnated dressings
- Iodine-based dressings
- Polyhexamethylene biguanide dressings
- Available as foams, hydrocolloids, or alginates
Important caveat: Check for allergies to dressing components, and remember that silver dressings cannot be worn during MRI procedures 1.
Clinical Context
Both Pseudomonas and Proteus are common pathogens in PEG site infections 2. The fluoroquinolone coverage is appropriate for both organisms, assuming susceptibility testing confirms sensitivity. The systemic antibiotic addresses the infection systemically, while antimicrobial dressings provide local wound management without the risks associated with topical antibiotics (such as promoting resistance or allergic reactions).
When to Escalate
If the infection does not resolve despite appropriate systemic antibiotics and antimicrobial dressings, the PEG tube should be removed 1. This is particularly important if there is stoma tract disruption, persistent peristomal infection despite treatment, or skin excoriation.