Pseudomonas aeruginosa Infection in Cancer Patients

Abstract

Pseudomonas aeruginosa is an important cause of infection in immunosuppressed patients, particularly those with cancer. However, it is being recognized with greater frequency in patients who appear to be immunocompetent. Changes in modern lifestyles have led to the appearance of some new manifestations of pseudomonas infection including corneal ulceration and keratitis associated with contact lenses, and hot-tub- or whirlpool-associated folliculitis. These represent additional hazards to patients with cancer. Many studies, both in animals and humans, have contributed to our knowledge of the pathogenesis, immunology, treatment, and prevention of pseudomonas infections. Although the aminoglycosides represented a significant step forward in the treatment of these infections, of greater importance was the discovery of the antipseudomonal penicillins. These antibiotics are more effective than the aminoglycosides in neutropenic patients, who are especially susceptible to pseudomonal infections. The older antipseudomonal penicillins (carbenicillin, tircarcillin) have largely been replaced by newer ones (mezlocillin, azlocillin, pipercillin) which are more potent in vitro against P. aeruginosa. Although the accepted therapeutic practice has been to utilize a penicillin in combination with an aminoglycoside, the introduction of newer beta lactam agents and fluoroquinolones with antipseudomonal properties offers the possibility of other approaches to combination therapy. These include the combination of a penicillin or a cephalosporin or the combination of a quinolone with an aminoglycoside or a betalactam antibiotic. However, the development of newer antimicrobial agents is not likely to be a lasting solution to the problem of pseudomonas infections. Since pseudomonas infection often progresses rapidly, optimal results will always depend upon the prompt initiation of appropriate therapy in febrile patients, particularly those who are at high risk. The use of granulocyte transfusions has proved to be of limited benefit. Early data with the use of monoclonal antibodies is promising, and the results of large-scale trials are eagerly awaited. It is hoped that continuing investigation of pseudomonas vaccines will lead to the discovery of effective prophylaxis for highly susceptible patients. It is also hoped that with the availability of GM-CSF it will become possible to reduce the period of risk for serious infections. Finally, a reduction in the frequency of microbiologically proven P. aeruginosa infections in cancer patients should not lead to the assumption that these organisms do not constitute a problem in such patients anymore. The use of prophylactic antibiotics and prompt empiric antibiotic coverage for therapy has resulted in this decline. Cultures are therefore unlikely to be positive with the same frequency as they were before antimicrobial prophylaxis and empiric antibiotic therapy became standard practice.(ABSTRACT TRUNCATED AT 400 WORDS)

N-(3-Oxo-acyl)homoserine Lactones Signal Cell Activation through a Mechanism distinct from the Canonical Pathogen-associated Molecular Pattern Recognition Receptor Pathways

“…Although further work is needed to identify and characterize specific subsets of C12-regulated genes, the effect on c-jun gene expression further emphasizes differences between signaling in response to pro-inflammatory stimuli and C12. Additionally, C12-induci- ble expression of the proto-oncogene c-jun may be relevant to P. aeruginosa infections in cancer patients (65).…”

Epidemiological investigation of Pseudomonas aeruginosa nosocomial bacteraemia isolates by PCR-based DNA fingerprinting analysis

“…were the first to were obtained. As bacteraemia cases were observed 2 compare the discriminatory power and the reproduciweeks-6 months after surgical implantation of the bility of hybridisation of restricted chromosomal DNA devices, contamination could have occurred during with a specific (tox A) probe, ribotyping and PFGE [ 5 ] . manipulation of infusion implants for the administraThey concluded that PFGE was the most powerful tool tion of anticancer therapy.…”

Antimicrobial Effects of Drugs against Multidrug-Resistant Pseudomonas aeruginosa

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Multidrug-resistant gram-negative rods such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae have presented problems.1,2) In particular, P. aeruginosa is an important species causing nosocomial infection, 3) and its development of multidrug-resistance has become a major social issue. [4][5][6] In Japan, multidrug-resistant P. aeruginosa was defined as isolates resistant to all of the following drugs: imipenem, MIC (minimum inhibitory concentration) Ն16 mg/ml; amikacin, MIC Ն32 mg/ml; and ciprofloxacin, MIC Ն4 mg/ ml.

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