What antibiotic treatment is recommended for a patient with a wound culture showing heavy growth of Staphylococcus aureus and few colonies of Acinetobacter lwoffi, who has recently taken Bactrim (Sulfamethoxazole/Trimethoprim) DS for 7 days?

From the Guidelines

The patient should be switched to a different antibiotic regimen, such as clindamycin 300-450 mg three times daily for 7-10 days, due to the heavy growth of Staphylococcus aureus and recent completion of Bactrim DS without resolution, suggesting possible Bactrim resistance. The few colonies of Acinetobacter lwoffi likely represent colonization rather than true infection. According to the guidelines by the Infectious Diseases Society of America 1, clindamycin is a recommended option for empirical coverage of CA-MRSA in outpatients with skin and soft tissue infections (SSTIs). The patient's recent completion of Bactrim DS without resolution suggests possible resistance, and clindamycin provides excellent coverage against methicillin-susceptible S. aureus (MSSA) with good tissue penetration.

• The wound should also be properly cleaned and dressed, with consideration for debridement if appropriate.
• Reassessment after 48-72 hours of therapy is recommended to ensure clinical improvement.
• If MRSA is suspected based on risk factors or local prevalence, consider alternative treatments such as doxycycline 100 mg twice daily or linezolid 600 mg twice daily 1.
• It is essential to note that the use of rifampin as a single agent or as adjunctive therapy for the treatment of SSTI is not recommended 1.
• The patient's clinical response should be individualized, and the duration of therapy should be adjusted accordingly, with a recommended range of 7-14 days 1.

From the FDA Drug Label

The Staphylococcus aureus isolate does not demonstrate inducible clindamycin resistance as determined by testing clindamycin in combination with erythromycin (D-test negative). Oxacillin (cefoxitin)-susceptible staphylococci can be considered susceptible to: amoxicillin-clavulanate, ampicillin-sulbactam, piperacillin-tazobactam, ticarcillin-clavulanate, cefaclor, cefdinir, cephalexin, cefpodoxime, cefprozil, cefuroxime, loracarbef, cefamandole, cefazolin, cefepime, cefmetazole, cefonicid, cefoperazone, cefotaxime, cefotetan, ceftizoxime, ceftriaxone, cefuroxime, cephalothin, ceftaroline, moxalactam, doripenem, ertapenem, imipenem, meropenem. Rifampin should not be used alone for antimicrobial therapy. Organisms that are susceptible to tetracycline are also considered susceptible to doxycycline and minocycline.

Based on the provided information, the recommended antibiotic treatment for the patient with a wound culture showing heavy growth of Staphylococcus aureus and few colonies of Acinetobacter lwoffi could be:

• Ceftaroline: The Staphylococcus aureus isolate is susceptible to ceftaroline with an MIC of <=0.5.
• Daptomycin: The Staphylococcus aureus isolate is susceptible to daptomycin with an MIC of <=0.5, as shown in the study 2.
• Vancomycin: Although not directly mentioned in the provided text, vancomycin is often used to treat Staphylococcus aureus infections, especially methicillin-resistant Staphylococcus aureus (MRSA), as shown in the study 3. It is essential to note that Acinetobacter lwoffi is also present, and its susceptibility pattern should be considered when choosing an antibiotic regimen. However, the provided information does not offer a clear recommendation for treating Acinetobacter lwoffi. Given the recent use of Bactrim (Sulfamethoxazole/Trimethoprim) DS, it is crucial to consider the potential for resistance and select an alternative antibiotic. The choice of antibiotic should be made based on the specific susceptibility pattern of the isolated organisms, the severity of the infection, and the patient's clinical condition.

From the Research

Antibiotic Treatment Recommendations

Based on the provided wound culture results, which show heavy growth of Staphylococcus aureus and few colonies of Acinetobacter lwoffi, the following antibiotic treatment options can be considered:

• The patient's recent use of Bactrim (Sulfamethoxazole/Trimethoprim) DS for 7 days should be taken into account when selecting an antibiotic regimen.
• The Staphylococcus aureus isolate does not demonstrate inducible clindamycin resistance, and it is susceptible to several antibiotics, including ceftaroline, daptomycin, and linezolid 4, 5, 6.
• Acinetobacter lwoffi is susceptible to several antibiotics, including ceftazidime, ciprofloxacin, gentamicin, and imipenem.

Treatment Options

The following treatment options can be considered:

• Linezolid, which has been shown to be effective against Staphylococcus aureus infections, including those caused by methicillin-resistant strains 4, 6.
• Daptomycin, which has been shown to be effective against Staphylococcus aureus infections, including those caused by methicillin-resistant strains 5.
• Ceftaroline, which has been shown to be effective against Staphylococcus aureus infections, including those caused by methicillin-resistant strains.
• Combination therapy with two or more antibiotics, such as daptomycin and linezolid, may be considered for severe or complicated infections 5.

Important Considerations

• The patient's recent use of Bactrim (Sulfamethoxazole/Trimethoprim) DS for 7 days should be taken into account when selecting an antibiotic regimen.
• The susceptibility patterns of the isolated organisms should be considered when selecting an antibiotic regimen.
• The potential for antibiotic resistance and the need for combination therapy should be considered when selecting an antibiotic regimen 7, 8.