Mechanism of Action
Beta-lactam antibiotics exert their antibacterial effect by inhibiting these enzymes responsible for bacterial cell wall synthesis.
What are penicillin-binding proteins (PBPs)?
This antibiotic class is notorious for causing photosensitivity, making patient counseling on sun protection essential.
What is tetracyclines?
This antibiotic has reliable coverage against MRSA but lacks activity against gram-negative organisms
What is vancomycin?
A patient with severe community-acquired pneumonia is started on ceftriaxone and azithromycin. The macrolide is included primarily to provide coverage for this category of pathogens.
What are atypical organisms (e.g., Legionella, Mycoplasma, Chlamydia)?
A 34-year-old otherwise healthy woman presents to clinic with 24 hours of fever, myalgias, and a positive influenza A test. She requests medication to shorten her illness. Her renal function is normal, and she has no contraindications.
Which antiviral is recommended? Include dosing and duration.
What is oseltamivir 75 mg twice daily for 5 days?
This antibiotic class inhibits bacterial protein synthesis by binding the 30S ribosomal subunit and is concentration dependent.
What are aminoglycosides?
This antifolate combination can cause hyperkalemia, increased serum creatinine without a true decrease in GFR, and bone marrow suppression.
What is sulfamethoxazole-trimethoprim?
This carbapenem lacks activity against Pseudomonas aeruginosa and Enterococcus species.
What is ertapenem?
What is a common spectrum of coverage error that providers make when treating aspiration pneumonia?
What is adding additional anerobic coverage with metronidazole?
A 68-year-old man is admitted with community-acquired pneumonia. CXR shows lobar consolidation. He has COPD and heart failure, but no MRSA or Pseudomonas risk factors.
Which inpatient antibiotic regimen is most appropriate?
What is ceftriaxone and azithromycin?
Fluoroquinolones primarily inhibit these bacterial enzymes involved in DNA replication.
What are DNA gyrase and topoisomerase IV?
This lincosamide is strongly associated with Clostridioides difficile infection, making it one of the highest-risk antibiotics for CDI.
What is clindamycin?
This cephalosporin is commonly remembered as the first cephalosporin with reliable MRSA activity.
What is ceftaroline?
A patient with uncomplicated gram-negative bacteremia due to E. coli UTI improves clinically and source control is achieved. Current evidence supports this total treatment duration.
What is 7 days?
A 56-year-old man with obesity and diabetes is hospitalized with COVID-19 pneumonia. He requires 4 L/min nasal cannula oxygen but is not on high-flow or mechanical ventilation. Labs show elevated CRP.
Which medication has proven mortality benefit in this scenario?
What is dexamethasone?
Daptomycin causes rapid bacterial death through this unique mechanism.
What is membrane depolarization leading to loss of membrane potential?
This beta-lactam can cause seizures, especially in patients with renal impairment or when dosed incorrectly at high levels.
What is imipenem-cilastatin?
This oral agent commonly used for uncomplicated cystitis covers E. coli but does not achieve adequate concentrations for pyelonephritis.
What is nitrofurantoin?
Empiric treatment of necrotizing fasciitis often includes vancomycin plus piperacillin-tazobactam and this additional agent to inhibit streptococcal toxin production.
What is linezolid or clindamycin?
A 75-year-old female with hypertension and chronic kidney disease presents with fever, chills, and difficulty breathing. Chest X-ray shows patchy infiltrates in both lower lobes. Blood cultures reveal Klebsiella pneumoniae, and her renal function is slightly impaired. What is the preferred empiric antibiotic regimen for Klebsiella pneumonia in this patient?
What is ceftriaxone?
The pharmacodynamic parameter most predictive of vancomycin efficacy against MRSA is this ratio.
What is AUC/MIC?
This antibiotic carries a severe adverse reaction for potentially fatal blood dyscrasias, including aplastic anemia, and is reserved for specific severe infections like VRE.
What is Linezolid?
This beta-lactamase inhibitor in Avycaz enhances the activity of ceftazidime by inhibiting class A, C, and some class D beta-lactamases.
What is Avibactam?
This is the minimum duration of IV antibiotic therapy recommended for uncomplicated Staphylococcus aureus bacteremia after blood culture clearance and exclusion of metastatic infection.
What is 14 days?
A 72-year-old ICU patient develops pneumonia after being intubated for 5 days following ARDS. Comorbidities include COPD, hypertension, and ESRD on renal replacement therapy. What risk factors are present for multidrug-resistant (MDR) pathogens? What empiric treatment would you select?
1. What is acute renal replacement therapy prior to VAP onset, ≥5 days of hospitalization prior to the occurrence of VAP, Acute respiratory distress syndrome (ARDS) preceding VAP.
2. What is cefepime/piperacillin-tazobactam/meropenem + vancomycin?