Epidemiological typing ofPseudomonas aeruginosa

Abstract

Current knowledge of the typing of Pseudomonas aeruginosa and new methods for characterizing strains are reviewed. A combination of serotyping as a primary screen with pyocin typing for finer discrimination between isolates gives valid epidemiological data, is within the scope of most clinical laboratories and is to be recommended. Phage typing and H typing do provide good discrimination but are not reproducible in practice because a reaction-difference rule has to be applied to phage patterns, and diphasic variation reduces the accuracy of the identification of flagellar antigens. A problem remains with cystic fibrosis isolates, which show considerable heterogeneity in surface properties. For these strains pyocin production typing by the revised method of Govan is indicated. Newer techniques such as isoenzyme profile and DNA probes of the chromosome require independent evaluation and due to their technical difficulty may not be adopted in a routine context for some years to come.

Ribotyping of Pseudomonas aeruginosa Strains Isolated from Surgical Intensive Care Patients

“…Epidemiologic associations of P. aeruginosa strains have usually been based on a combination of serotyping as a primary screen and pyocin typing for additional discrimination [9]. However, the frequency of individual 0 types of P. aeruginosa in clinical specimens has varied with the country of investigation and the source of the isolate.…”

“…In addition, --8% Rectum (2). decubitus ( of clinical isolates react strongly with a pooled serum but fail to be agglutinated by individual ones [9]. Pyocin as well as phage typeability rates are high but of low reproducibility and discriminatory power, factors that affect the reliability of most typing methods in epidemiologic investigations of P. aeruginosa [10].…”

Multiresistant serotype O 12Pseudomonas aeruginosa: evidence for a common strain in Europe

“…The traditional methods for the typing of P. aeruginosa are in the main relatively discriminating (25), but the uniformity of phage lytic patterns and pyocin types of the 0 12 strains was considered to be insufficient evidence to allow confirmation of strain relatedness. All 0 12 strains were lysed by only one or two of the standard typing phages, or not at all, and pyocin typing failed to discriminate further between strains.…”

Pseudomonas aeruginosacross-colonization and persistence in patients with cystic fibrosis. Use of a DNA probe

“…Thus, loss of high molcular weight lipopolysaccharide in mucoid P. aeruginosa isolates from CF patients render strains non-typable with 0-specific antibodies. Furthermore, CF isolates are less sensitive to lysis by typing phages than are those from other patients (Pitt, 1988). Lastly, different pyocin patterns occur with changes in bacterial metabolism and antibiotic therapy may alter pyocin production patterns (Thomassen, Demko & Doershuk, 1987).…”