ORIGINAL ARTICLES   

Minerva Urologica e Nefrologica 1999 December;51(4):217-26

Copyright © 2000 EDIZIONI MINERVA MEDICA

language: Italian

Frequency and antibiotics susceptibility of urinary pathogens isolated in the microbiology and virology laboratory of the A.O. of Careggi, Florence (July 1996-December 1996)

Anichini P., Bordonaro P., Fontanelli A., Nicoletti P.

Azienda Ospedaliera «Careggi» - Firenze, Laboratorio di Microbiologia e Virologia

Background. The aim of the study was to evaluate the isolation frequency and antibiotic susceptibility of pathogens isolated form urinocoltures.
Methods. 2192 bacterial strains obtained from urine coltures with bacterial count >100,000 UFC/ml were examined in our Laboratory from July through December 1996. Inpatients as well as outpatients were considered. Five different ward typologies were taken into account (Surgery, Medicine, Obstetrics, Spinal Unit and High Risk Wards). Isolation frequencies were evaluated for each ward, but in order to get an adequate statistical sample they were divided into in two categories, e.g. strains isolated from inpatients and from outpatients. Antibiotic susceptibility was also evaluated dividing the data into the same two categories. For strains isolated with lower frequencies that was not possible, and data from inpatients were grouped with data from outpatiens.
Results. The results obtained show that bacterial species most frequently isolated among inpatiens are Escherichia coli (45.7%), Enterococcus faecalis (16.8%), Proteus mirabilis (9.1%), Pseudomonas aeruginosa (6.9%) and Klebsiella pneumoniae (6.4%). Those most frequently isolated among outpatiens are Escherichia coli (58.1%), Enterococcus faecalis (12.3%), Proteus mirabilis (9.1%), Klebsiella pneumoniae (4.4%) and Coagulase negative staphylococci (4.0%). As far as antibiotic susceptibility is concerned, whenever a statistically significant difference in sensitivity could be observed between strains isolated from inpatients and strains isolated from outpatients, sensitivity was always higher for outpatients strains.
Conclusions. Isolation frequency and antibiotic susceptibility are different depending on the place of origin of the patients (inpatients/ outpatients). This implies a different approach to the empiric therapy in urinary tract infections.