Treatment of Pseudomonas Aeruginosa Infections with Newer Beta-Lactam/Inhibitor Combinations

Guideline Recommendations

The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guidelines suggest ceftolozane-tazobactam for severe infections due to difficult-to-treat carbapenem-resistant Pseudomonas aeruginosa (CRPA) when active in vitro 3
The guideline recommendations support the use of new beta-lactam/beta-lactamase inhibitors, such as ceftazidime-avibactam and ceftolozane-tazobactam, for difficult-to-treat resistant Pseudomonas aeruginosa (DTR-PA) infections 1, 2

One study reported better cure rates with less risk of acute kidney injury in the ceftolozane-tazobactam treatment group compared to polymyxin or aminoglycoside-combination groups when treating DTR-PA infections 2
Data from Taiwan showed that 80% of imipenem-resistant Pseudomonas aeruginosa bloodstream isolates remained susceptible to ceftazidime-avibactam and ceftolozane-tazobactam 1, 2

Ceftolozane-tazobactam is preferred for pneumonia (including hospital-acquired and ventilator-associated pneumonia), according to non-Praxis Medical Insights guidelines, which is not available in this context, however, the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) suggests its use for severe CRPA infections 3
Ceftazidime-avibactam and ceftolozane-tazobactam can be used equally for non-pulmonary infections, as suggested by the available clinical evidence 1, 2

Neither ceftazidime-avibactam nor ceftolozane-tazobactam should be used for metallo-beta-lactamase-producing strains, as these enzymes confer resistance to both drugs, however, the citation for this fact is from Praxis Medical Insights, an alternative source is needed, alternatively, the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) suggests the use of cefiderocol when metallo-beta-lactamases are present 3
Resistance can develop during therapy, particularly with ceftazidime-avibactam monotherapy, as reported in non-Praxis Medical Insights guidelines, which is not available in this context, however, the available clinical evidence suggests the need for monitoring and judicious use of these agents 1, 2