What antibiotic regimen is recommended for a patient with a beta-lactamase (beta-lactam enzyme) positive culture?

From the Guidelines

For patients with beta-lactamase positive cultures, the recommended antibiotic regimen is Ceftolozane/Tazobactam 1.5 g 8-hourly + Metronidazole 500 mg 6-hourly or Ceftazidime/Avibactam 2.5 g 8-hourly + Metronidazole 500 mg 6-hourly, as these combinations have been shown to be effective against beta-lactamase producing organisms 1. The choice of antibiotic regimen should be guided by the severity of the infection, the susceptibility of the organism, and the patient's clinical response.

• In patients with suspected or proven infection with MDR (non-metallo-beta-lactamase-producing) Pseudomonas aeruginosa, consider use of antibiotic combinations with Ceftolozane/Tazobactam 1.
• In patients with suspected or proven infection with carbapenemase-producing Klebsiella pneumoniae, consider use of antibiotic combinations with Ceftazidime/Avibactam 1.
• In patients with documented beta-lactam allergy, consider use of antibiotic combinations with Amikacin 15–20 mg/kg 24-hourly 1. It is essential to note that the treatment regimen should be tailored to the individual patient's needs and should be based on clinical response, rather than solely on a predetermined protocol 1.
• The use of vasopressor agents may be necessary to augment and assist fluid resuscitation, particularly in patients who are not responding to fluid therapy alone 1.
• The duration of treatment should be guided by the severity of the infection and the patient's clinical response, and should generally range from 7-14 days depending on the site and severity of the infection.

From the FDA Drug Label

AVYCAZ is a combination of ceftazidime, a cephalosporin, and avibactam, a beta-lactamase inhibitor, indicated for the treatment of the following infections caused by designated susceptible Gram-negative microorganisms in adult and pediatric patients AVYCAZ (ceftazidime and avibactam) is indicated for the treatment of complicated urinary tract infections (cUTI) including pyelonephritis in adult and pediatric patients (at least 31 weeks gestational age) caused by the following susceptible gram-negative microorganisms: To reduce the development of drug-resistant bacteria and maintain the effectiveness of AVYCAZ and other antibacterial drugs, AVYCAZ should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria.

The recommended antibiotic regimen for a patient with a beta-lactamase positive culture is AVYCAZ (ceftazidime and avibactam), as it contains a beta-lactamase inhibitor, which can help combat beta-lactamase producing bacteria. The dosage and administration of AVYCAZ vary depending on the patient's age, weight, and renal function, as outlined in the drug label 2, 2, and 2.

• Key points:
  • AVYCAZ is a combination of ceftazidime and avibactam.
  • It is indicated for the treatment of complicated urinary tract infections (cUTI) and other infections caused by susceptible Gram-negative microorganisms.
  • The dosage and administration of AVYCAZ depend on the patient's age, weight, and renal function.
  • AVYCAZ should be used to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria.

From the Research

Antibiotic Regimen for Beta-Lactamase Positive Culture

• The recommended antibiotic regimen for a patient with a beta-lactamase positive culture includes the use of beta-lactam/beta-lactamase inhibitor combinations, such as piperacillin/tazobactam 3, ampicillin-sulbactam 4, or ticarcillin-clavulanic acid 4.
• Piperacillin/tazobactam has been shown to be effective in treating various infections, including lower respiratory tract, intra-abdominal, urinary tract, gynaecological, and skin/soft tissue infections, as well as fever in patients with neutropenia 3.
• The use of piperacillin/tazobactam in combination with an aminoglycoside has been shown to be effective in treating severe nosocomial infections 3 and febrile neutropenia 3.
• However, the efficacy of piperacillin/tazobactam against extended-spectrum beta-lactamase (ESBL)-producing organisms is still a topic of debate 5, 6.
• A study found that piperacillin/tazobactam may be an effective alternative to carbapenems for the treatment of nonbacteremic urinary tract infections due to ESBL-producing Enterobacteriaceae 6.
• Another study found that combination therapy with a beta-lactam drug and an aminoglycoside showed no advantage over monotherapy with a single beta-lactam drug, except in cases of neutropenic patients or those with Pseudomonas aeruginosa bacteremia 7.

Key Considerations

• The choice of antibiotic regimen should be based on the specific type of infection, the severity of the infection, and the susceptibility of the organism to the antibiotic 3, 4, 5, 6, 7.
• The use of beta-lactam/beta-lactamase inhibitor combinations, such as piperacillin/tazobactam, should be considered in cases where the organism is suspected to be beta-lactamase positive 3, 4.
• The addition of an aminoglycoside to the antibiotic regimen may be considered in cases of severe infections or in patients with specific risk factors, such as neutropenia or Pseudomonas aeruginosa bacteremia 3, 7.