Stanford Antimicrobial Safety & Sustainability Program

🔍 While skin swabs in patients with cellulitis are often not helpful (as they can reflect colonization), I&D (incision and drainage) of a purulent abscess is beneficial. Culture with susceptibility testing allows for targeted antibiotic use.

💡 A: The first step when evaluating a patient with SSTI is to assess for purulence, which can be manifested as “lumps, bumps, or pus.”

Empiric MRSA coverage is indicated for purulent SSTI, not non-purulent SSTI.

🌟 ABX Pearl of the Day:

❓ Q: When should you consider empiric MRSA coverage for SSTI treatment?

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📄 See more FAQs on the nasal MRSA PCR test: Stanford Bugs and Drugs Guidebook med.stanford.edu/bugsanddrugs...

🔍If the patient has improved quickly and was never producing sputum, they are less likely to have had MRSA as a causative organism. In this case, the positive MRSA PCR likely represents colonization rather than active infection. Vancomycin can likely be discontinued after 48 hours

💡 A: The decision to de-escalate should be made clinically.

⚠️ Clinically, MRSA pneumonia tends to be aggressive, with significant local tissue destruction, leading to positive culture results. Patients are often quite ill and improve much more slowly.

🌟 ABX Pearl of the Day: (Part 2)

❓Q: If my patient with pneumonia has a positive MRSA nasal PCR but respiratory cultures are NOT available, do I need to continue vancomycin for a full course of therapy?

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References:
Diagn Microbiol Infect Dis. 2016 Nov;86(3):307-310
Am J Infect Control. 2017 Nov 1;45(11):1295-1296

✅ The true utility of the MRSA PCR is in its high negative predictive value (NPV) of >98%, making it a useful tool for clinicians considering de-escalation or discontinuation of vancomycin (or linezolid) for suspected MRSA pneumonia.

🔄 It is reasonable to de-escalate MRSA coverage (vancomycin or linezolid) if a timely, adequate respiratory sample is negative for MRSA.

💡 A: No. A positive nasal MRSA PCR alone is not recommended for the diagnosis of MRSA pneumonia given its poor positive predictive value (PPV) of 34.5% relative to respiratory culture.

🌟 ABX Pearl of the Day:

❓ Q: If my patient with pneumonia has a positive MRSA nasal PCR but respiratory cultures are negative for MRSA, do I need to continue vancomycin for a full course of therapy?

#IDsky #medsky #meded #pharmsky #skyRX #AMSsky

📚 References:
Pappas PG, Kauffman CA, Andes DR, Clancy CJ, Marr KA, Ostrosky-Zeichner L et al. Clinical practice guideline for the management of candidiasis: 2016 update by the Infectious Diseases Society of America. Clin Infect Dis 2016; 62: e1–50.

med.stanford.edu/bugsanddrugs...

⚠️ If there’s concern for symptomatic Candida cystitis, pyelonephritis, or fungal ball, we recommend consulting Infectious Diseases.

🔍 That said, Candida species are normal respiratory and skin flora. Isolates from non-sterile sites (e.g., sputum, BAL, urine, indwelling drains) are generally considered colonizers and do not require targeted antifungal therapy.

💡 A: You should always assume that isolating Candida from blood warrants treatment and is NOT a contaminant.

🌟 ABX Pearl of the Day:

❓ Q: Candida only grew in 1/4 bottles. Is this a contaminant?

#IDsky #medsky #meded #pharmsky #skyRX #AMSsky

Unraveling indications for discharge antibiotics: the Devil’s in the details | Antimicrobial Stewardship & Healthcare Epidemiology | Cambridge Core Unraveling indications for discharge antibiotics: the Devil’s in the details - Volume 5 Issue 1

@ritikaprasad.bsky.social @stanfordasp.bsky.social @marisa-holubar.bsky.social: The inpatient mandatory indication field outperformed the ICD-10 in inferring dc abx indications, and can be used to assess abx appropriateness without needing manual chart review.
doi.org/10.1017/ash....

🤝 ID consultation is recommended for all patients with candidemia, cryptococcemia, or other yeast bloodstream infections.

📊 See the figure below to review antifungal coverage.

⚠️ Rapid distinction is crucial since caspofungin (and other echinocandins) are not effective for treating cryptococcal infections.

🔍 If there’s concern for non-Candida yeast in the blood, communicate early with the Microbiology Lab to aid in identification.

💡 A: Yeast in blood cultures is most often identified as Candida. However, other forms of yeast, such as Cryptococcus, can also be isolated from blood, especially in immunocompromised patients (e.g., HIV/AIDS, decompensated cirrhosis, SOT).

🌟 ABX Pearl of the Day:

❓ Q: My patient is growing yeast in blood cultures. Is this Candida?

#IDsky #medsky #meded #pharmsky #skyRX #AMSsky

📚 References:
Ramirez JA et al. Treatment of Community-Acquired Pneumonia in Immunocompromised Adults: A Consensus Statement. 2020 Nov;158(5):1896-1911. PMID: 32561442

med.stanford.edu/bugsanddrugs...

🤝 Consider an ID consult if there’s concern for complicated pneumonia (abscess/cavity, empyema), opportunistic infection, or history of colonization with MDROs.

See figure for MRSA and PsA Risk factors in CAP from Stanford.

💊 If your patient lacks these risk factors, consider CAP treatment with ceftriaxone and azithromycin.

💡 A: The IDSA CAP guidelines don’t specifically address this population. However, a CHEST consensus statement recommends expanded empiric therapy for pts with risk factors for MRSA or Pseudomonas, especially if a delay in ABX could increase mortality risk (e.g., severe pneumonia or ICU admission).

🌟 ABX Pearl of the Day:

❓ Q: My immunocompromised patient is admitted to the ICU and starting ABX for presumed CAP. Do they need empiric MRSA and Pseudomonas coverage?

#IDsky #medsky #meded #pharmsky #skyRX #AMSsky

📄 Learn more about fosfomycin in our Tip Sheet: med.stanford.edu/content/dam/...