Is Pseudomonas aeruginosa a serious infection?

From the Guidelines

Yes, Pseudomonas aeruginosa is a serious infection that requires prompt medical attention. This gram-negative bacterium can cause severe, life-threatening infections, particularly in people with weakened immune systems, hospitalized patients, and those with certain chronic conditions like cystic fibrosis. Pseudomonas is concerning because it has natural resistance to many antibiotics and can develop additional resistance during treatment. Common infections include pneumonia, urinary tract infections, bloodstream infections, and wound infections following surgery or burns.

Key Considerations

• The incidence of Pseudomonas aeruginosa infections seems to be low 1, but the bacterium is particularly dangerous due to its ability to form biofilms and produce toxins and enzymes that damage tissues and evade host defenses.
• Treatment typically involves potent antibiotics such as antipseudomonal penicillins, carbapenems, cephalosporins, fluoroquinolones, or aminoglycosides, often in combination therapy to prevent resistance development 1.
• The specific antibiotic regimen depends on infection site, severity, and local resistance patterns, with treatment courses typically lasting 7-14 days, though longer for severe infections.
• In patients with risk factors for P. aeruginosa, meropenem offers advantages over imipenem because of the option to increase the dose significantly up to 3 · 2 g 1.
• Patients at risk of P. aeruginosa infection should always be treated with two antipseudomonal drugs to reduce the chance of inadequate treatment 1.

Management Strategies

• For patients with severe community-acquired pneumonia, treatment options include antipseudomonal cephalosporin or acylureidopenicillin/b-lactamase inhibitor or carbapenem (meropenem preferred) plus ciprofloxacin or macrolide + aminoglycoside (gentamicin, tobramycin or amikacin) 1.
• Aerosolized antibiotics, such as tobramycin, may be used to prevent P. aeruginosa pulmonary infection in cystic fibrosis patients 1.
• Monitoring of serum aminoglycoside concentrations is recommended for patients receiving high doses of aerosolized antibiotics 1.

From the FDA Drug Label

Tobramycin for Injection, is an aminoglycoside antibacterial indicated for the treatment of serious bacterial infections caused by susceptible isolates of the designated bacteria in the diseases listed below (1. 1): Septicemia in the pediatric patient and adults caused by P. aeruginosa, E. coli, and Klebsiella species (spp). Skin, bone, and skin structure infections caused by P. aeruginosa, Proteus spp, E. coli, Klebsiella spp., Enterobacter spp., and S. aureus. Complicated urinary tract infections caused by P. aeruginosa, Proteus spp., (indole-positive and indole-negative), E. coli, Klebsiella spp., Enterobacter spp., Serratia spp., S. aureus, Providencia spp., and Citrobacter spp.

Yes, Pseudomonas aeruginosa is considered a serious infection as it is listed among the indications for the use of Tobramycin for Injection, an aminoglycoside antibacterial, for the treatment of serious bacterial infections 2.

• Serious infections caused by P. aeruginosa include:
  • Septicemia
  • Skin, bone, and skin structure infections
  • Complicated urinary tract infections
  • Lower respiratory tract infections

From the Research

Overview of Pseudomonas aeruginosa Infections

• Pseudomonas aeruginosa is a serious infection that can cause significant morbidity and mortality, especially in critically ill and immunocompromised patients 3, 4.
• The infection is commonly associated with hospital-acquired infections, and the appearance of drug-resistant strains is a major concern 3, 5.

Risk Factors and Patient Groups

• Certain patient groups are at higher risk of developing Pseudomonas aeruginosa infections, including those with burn wounds, cystic fibrosis, acute leukemia, organ transplants, and intravenous-drug addiction 6.
• Patients who are hospitalized for extended periods are also at increased risk of developing infection 6.

Types of Infections and Severity

• Pseudomonas aeruginosa can cause a range of infections, including malignant external otitis, endophthalmitis, endocarditis, meningitis, pneumonia, and septicemia 6.
• The likelihood of recovery from Pseudomonas aeruginosa infection is related to the severity of the patient's underlying disease process 6.
• The infection can be severe, with reported mortality rates of up to 61% 4.

Treatment and Antibiotic Resistance

• The treatment of Pseudomonas aeruginosa infections often involves the use of antipseudomonal antibiotics, and combination therapy may be recommended to ensure adequate coverage 5, 4.
• However, the increasing resistance of Pseudomonas aeruginosa isolates to antibiotics complicates the selection of adequate empirical therapy 3, 5.
• New antibiotics, such as ceftolozane/tazobactam, have shown activity against Pseudomonas aeruginosa, including multidrug-resistant isolates 7.