Typing of Pseudomonas aeruginosa from hospitalized patients: a comparison of susceptibility and biochemical profiles with genotype

Abstract

Typing techniques are essential for understanding hospital epidemiology, permitting the elucidation of the source of infection and routes of bacterial transmission. Although DNA-based techniques are the "gold standard" for the epidemiological study of Pseudomonas aeruginosa, antibiotic profiles and biochemical results are used because they are easy to perform and to interpret and relatively inexpensive. Antibiotypes (susceptibility profiles) and biotypes (biochemical profiles) were compared to genotypes established by DNA restriction enzyme analysis in 81 clinical isolates of P. aeruginosa from three hospitals in Porto Alegre, Brazil. The epidemiological relationship among patients was also evaluated. Susceptibility and restriction profiles were discrepant in more than 50% of the cases, and many antibiotypes were observed among isolates from the same genotype. Furthermore, susceptibility profiles did not allow the distinction of isolates from unrelated genotypes. Since a large number of isolates (63%) yielded the same biochemical results, only 10 biotypes were detected, showing that this typing method has a low discriminatory power. On the other hand, DNA restriction enzyme typing allowed us to establish 71 distinct types. Epidemiological data about the relation among P. aeruginosa isolates were not conclusive. The results of the present study indicate that the only method that can establish a clonal relation is DNA restriction enzyme typing, whereas the other methods may cause misleading interpretations and are inadequate to guide proper infection control measures.

Nosocomial infections in human immunodeficiency virus type 1 (HIV-1) infected and AIDS patients: major microorganisms and immunological profile

“…This result is in agreement with the previous reports which affirmed that P. aeruginosa is common in NIs and is pointed as an important agent of morbidity and mortality among HIV-1 patients because it can be fatal in the advanced stages of HIV-1 disease, specially when the CD4 + T cell counting is low (11,22,31). Pseudomonas spp.…”

Clonal Analysis of Clinical and Environmental Pseudomonas aeruginosa Isolates from Meknes Region, Morocco

“…Clinical isolates were also highly diverse, the level detected (76.9%) is higher than that reported by Selim et al (2015) signaling 50% of polymorphism in P. aeru ginosa isolates from Egypt. However it remains slightly lower than that obtained by Freitas and Barth (2004) indicating 71 PFGE types in 81 clinical isolates from 3 Brazilian hospitals. Obtained polymorphism is also lower than that reported by Lim et al (2009) signaling 93.7% of polymorphism among 48 P. aeruginosa isolates from 6 Malaysian hospitals.…”

Pseudomonas aeruginosa isolates recovered from clinical and environmental samples in Buea, Cameroon: current status on biotyping and antibiogram

“…We are therefore constrained to speculate that patients’ beds might have served as a vehicle for contaminating wounds. In a similar study in Brazil, Freitas and Barth (2004) typed P. aeruginosa using a combination of biotyping, antibiotyping and DNA typing to characterize P. aeruginosa isolates from hospitalized patients. They detected 10 biotypes among their isolates and concluded that biotyping has a low discriminatory power thus corroborating our results.…”