bacteremia Flashcards
Q: What is bacteremia and what are the potential sources?
A: Bacteremia is the presence of bacteria in the bloodstream. Potential sources include infections from urinary tract, respiratory tract, skin and soft tissues, gastrointestinal tract, and intravascular devices.
Q: What are the key risk factors for developing bacteremia?
A: Key risk factors include immunosuppression (e.g., diabetes mellitus, malignancy), invasive procedures, presence of intravascular devices (e.g., catheters), chronic diseases (e.g., renal failure, liver disease), and recent surgeries or trauma.
Q: How is bacteremia diagnosed?
A: Bacteremia is diagnosed through blood cultures, ideally obtained before starting antibiotics. Additional diagnostic tools include imaging studies and echocardiography if endocarditis is suspected.
Q: Describe the typical clinical presentation of a patient with bacteremia.
A: Patients with bacteremia may present with fever, chills, rigors, hypotension, tachycardia, altered mental status, or symptoms specific to the infection source (e.g., dysuria, cough, wound infection).
Q: What is the initial empiric antibiotic therapy for a patient with suspected bacteremia?
A: Initial empiric therapy often includes broad-spectrum antibiotics such as vancomycin plus piperacillin-tazobactam, tailored based on local antibiogram data and patient-specific factors.
Q: What is the role of follow-up blood cultures in the management of bacteremia?
A: Follow-up blood cultures, typically obtained 48-72 hours after starting treatment, help ensure clearance of the bacteremia and guide adjustments in antibiotic therapy.
Q: How is methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia treated?
A: MSSA bacteremia is treated with antistaphylococcal penicillins (e.g., nafcillin, oxacillin) or cefazolin.
Q: What are the first-line treatments for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia?
A: First-line treatments for MRSA bacteremia include vancomycin or daptomycin.
Q: Describe the treatment approach for Gram-negative bacteremia, particularly with extended-spectrum beta-lactamase (ESBL) producers.
A: Gram-negative bacteremia, particularly with ESBL producers, is treated with carbapenems (e.g., meropenem, imipenem-cilastatin, ertapenem).
Q: What should be done if a patient with bacteremia shows signs of sepsis or septic shock?
A: Immediate management includes aggressive fluid resuscitation, vasopressors if needed, prompt initiation of broad-spectrum antibiotics, and source control (e.g., drainage of abscesses, removal of infected devices).
Q: What are the indications for using echocardiography in bacteremia cases?
A: Echocardiography is indicated if endocarditis is suspected, particularly in cases involving Staphylococcus aureus, Enterococcus species, or fungi, or in patients with prosthetic heart valves or certain congenital heart diseases.
Q: How should bacteremia in immunocompromised patients be managed differently?
A: In immunocompromised patients, empiric antibiotic therapy should cover a broad range of pathogens, including fungi and resistant bacteria, and invasive diagnostic procedures may be more frequently required.
Q: How should central line-associated bloodstream infections (CLABSI) be managed?
A: Management of CLABSI includes removal of the catheter, obtaining blood cultures from peripheral and catheter sites, and starting empiric antibiotic therapy. Catheter tip culture may also be performed to identify the pathogen.
Q: What are the complications associated with untreated or inadequately treated bacteremia?
A: Complications can include sepsis, septic shock, metastatic infections (e.g., endocarditis, osteomyelitis, abscesses), multi-organ failure, and death.
Q: What is the role of antimicrobial stewardship in the treatment of bacteremia?
A: Antimicrobial stewardship involves selecting the appropriate empiric therapy, de-escalating therapy based on culture results, minimizing unnecessary antibiotic use, and reducing the risk of antibiotic resistance.
