What is the appropriate antibiotic treatment for Methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative (Gram negativo) and Gram-positive (Gram positivo) pneumonia using Piperacillin/Tazobactam (Pipertazo) and Vancomycin?

From the Guidelines

For a patient with pneumonia caused by MRSA and gram-negative cocci, the combination of piperacillin-tazobactam and vancomycin is an appropriate empiric therapy, as recommended by the Infectious Diseases Society of America and the American Thoracic Society 1.

Key Considerations

• Vancomycin specifically targets MRSA, while piperacillin-tazobactam provides broad-spectrum coverage against gram-negative organisms.
• For vancomycin, the typical adult dosing is 15-20 mg/kg IV every 8-12 hours (adjusted based on renal function), with target trough levels of 15-20 μg/mL for pneumonia, as outlined in the guidelines 1.
• Piperacillin-tazobactam is typically dosed at 4.5g IV every 6-8 hours for normal renal function.

Treatment Approach

• This combination should be continued until culture results and susceptibilities are available, typically for 7-14 days depending on clinical response.
• Monitor for vancomycin-associated nephrotoxicity and adjust dosing based on levels.
• Once culture results return, therapy should be narrowed to the most appropriate agent(s) to reduce the risk of developing resistance and adverse effects from unnecessary antibiotics.

Guiding Principles

• The choice between vancomycin and linezolid may be guided by patient-specific factors such as blood cell counts, concurrent prescriptions for serotonin-reuptake inhibitors, renal function, and cost, as noted in the guidelines 1.
• The Infectious Diseases Society of America and the American Thoracic Society recommend that MRSA HAP/VAP be treated with either vancomycin or linezolid rather than other antibiotics or antibiotic combinations (strong recommendation, moderate-quality evidence) 1.

From the FDA Drug Label

1. 2 Nosocomial Pneumonia Piperacillin and tazobactam for injection, USP is indicated in adults and pediatric patients (2 months of age and older) for the treatment of nosocomial pneumonia (moderate to severe) caused by beta-lactamase producing isolates of Staphylococcus aureus and by piperacillin and tazobactam-susceptible Acinetobacter baumannii, Haemophilus influenzae, Klebsiella pneumoniae, and Pseudomonas aeruginosa

• MRSA (Methicillin-resistant Staphylococcus aureus) is not explicitly mentioned in the label as being covered by piperacillin/tazobactam.
• Cocci Gram-negative and Cocci Gram-positive pneumonia are not explicitly addressed in the label.
• The label does mention Staphylococcus aureus, but it does not specify if this includes MRSA.
• Vancomycin is not mentioned in the label as a comparator or alternative to piperacillin/tazobactam.
• Piperacillin/tazobactam is indicated for nosocomial pneumonia caused by certain bacteria, but the label does not provide information on its effectiveness against MRSA or Cocci Gram-negative and Gram-positive pneumonia 2

From the Research

MRSA and Pneumonia Treatment

• The treatment of MRSA pneumonia often involves the use of antibiotics such as vancomycin and piperacillin-tazobactam 3, 4.
• Studies have shown that the combination of vancomycin and piperacillin-tazobactam can be effective against MRSA, with synergy observed in vitro and in vivo 3, 4.
• The use of vancomycin and piperacillin-tazobactam in combination has been shown to achieve a significant reduction in bacterial growth and enhance antimicrobial activity against MRSA and vancomycin-intermediate Staphylococcus aureus (VISA) 4.

Antibiotic Options

• Other antibiotics that have been used to treat MRSA pneumonia include linezolid, teicoplanin, and daptomycin 5, 6.
• Linezolid has been shown to be effective against MRSA bacteremia, with comparable effectiveness and safety to vancomycin, teicoplanin, and daptomycin 7.
• The choice of antibiotic will depend on various factors, including the severity of the disease, the setting of occurrence, and the patient's baseline risk of toxicity and drug interactions 6.

Cocci Gram-Negative and Gram-Positive Pneumonia

• The treatment of pneumonia caused by gram-negative and gram-positive cocci will depend on the specific organism and its antibiotic susceptibility pattern.
• Vancomycin and piperacillin-tazobactam may be effective against gram-positive cocci, while other antibiotics such as ceftazidime or cefepime may be effective against gram-negative cocci 4.
• The use of antibiotic combinations, such as vancomycin and piperacillin-tazobactam, may be necessary to ensure adequate coverage against both gram-positive and gram-negative organisms 3, 4.