Antibiotic Coverage
This antibiotic class is commonly used for uncomplicated streptococcal skin infections when MRSA coverage is not needed.
What are the beta-lactams, such as penicillins or cephalosporins?
This gram-positive coccus is the most common cause of uncomplicated cellulitis and erysipelas.
What is Streptococcus pyogenes?
This gram-negative rod is the most common cause of uncomplicated urinary tract infections.
What is Escherichia coli?
This anaerobic organism is part of normal GI flora and is an important cause of intra-abdominal abscesses.
What is Bacteroides fragilis?
This group is called atypical because they lack this feature of a typical bacterial pathogen.
What is a cell wall?
A patient has a purulent skin abscess requiring antibiotic treatment because of surrounding cellulitis and systemic symptoms. This organism must be considered when choosing empiric therapy.
What is MRSA?
This gram-positive coccus is a major cause of skin abscesses and may be either methicillin-sensitive or methicillin-resistant.
What is Staphylococcus aureus?
This gram-negative diplococcus can cause meningitis and meningococcemia, often presenting with fever, headache, neck stiffness, and a rapidly developing petechial or purpuric rash.
What is Neisseria meningitidis?
This antibiotic has excellent anaerobic coverage and is commonly combined with other agents when broad-spectrum treatment is needed.
What is metronidazole?
This atypical respiratory pathogen lacks a cell wall, making beta-lactam antibiotics ineffective.
What is Mycoplasma pneumoniae?
A young adult has a persistent dry cough and patchy infiltrates. Mycoplasma pneumoniae is suspected. This class of antibiotics provides appropriate coverage.
What are macrolides?
An older adult develops pneumonia following influenza. Sputum culture grows gram-positive, lancet-shaped diplococci.
What is Streptococcus pneumoniae?
This oxidase-positive, non-lactose-fermenting gram-negative rod is an important cause of healthcare-associated pneumonia and is associated with burn wounds.
What is Pseudomonas aeruginosa?
A patient develops profuse watery diarrhea after receiving clindamycin. The causative organism is a gram-positive, spore-forming anaerobic rod.
What is Clostridioides difficile?
A sexually active patient presents with dysuria and mucopurulent cervical discharge. NAAT testing is positive for an obligate intracellular bacterium that commonly causes cervicitis and urethritis but may be asymptomatic.
What is Chlamydia trachomatis?
A patient with community-acquired pneumonia needs treatment that covers typical respiratory bacteria plus atypical organisms. Name one commonly used outpatient regimen.
What is amoxicillin plus doxycycline or a macrolide?
A patient has a prosthetic heart valve and develops subacute endocarditis caused by a coagulase-negative, gram-positive coccus that commonly colonizes skin.
What is Staphylococcus epidermidis?
This lactose-fermenting gram-negative rod is associated with pneumonia, urinary infections, and infections in hospitalized patients and can produce ESBL (Extended-Spectrum Beta-Lactamases) enzymes.
What is Klebsiella pneumoniae?
A patient develops severe muscle pain and rapidly progressive swelling after a traumatic wound. Imaging reveals gas within the soft tissues, and the wound produces a foul-smelling discharge. This anaerobic, gram-positive, spore-forming rod is the classic cause.
What is Clostridium perfringens?
This organism can cause atypical pneumonia associated with diarrhea, hyponatremia, and exposure to contaminated water systems.
What is Legionella pneumophila?
A patient with a serious infection has a history of anaphylaxis to penicillin. The clinician wants empiric therapy covering MRSA, Pseudomonas, and anaerobes. One possible approach is vancomycin plus an antipseudomonal agent plus this drug specifically for anaerobic coverage.
What is metronidazole?
A hospitalized patient develops bacteremia caused by a gram-positive organism that is resistant to vancomycin because of an altered cell-wall target.
What is VRE (Enterococcus faecium/faecalis)?
A sexually active patient has urethritis. The organism is a gram-negative diplococcus that can be treated with ceftriaxone.
What is Neisseria gonorrhoeae?
A patient develops a foul-smelling dental infection involving anaerobic oral flora. This oral antibiotic provides both aerobic gram-positive and anaerobic coverage.
What is amoxicillin-clavulanate? (Augmentin)
A patient with atypical pneumonia has a history of recent exposure to contaminated water from a large building's plumbing system. Which antibiotic class is particularly important because this organism is intracellular?
What are macrolides or fluoroquinolones?