[Frequency and antibiotic susceptibility of urinary pathogens isolated in the microbiology and virology laboratory of the Careggi General Hospital in the period July-December 1996].
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 cultures 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 outpatients.


RESULTS
The results obtained show that bacterial species most frequently isolated among inpatients 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 outpatients 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.
Anichini
P
P
Laboratorio di Microbiologia e Virologia, Azienda Ospedaliera Careggi, Firenze.
Bordonaro
P
P
Fontanelli
A
A
Nicoletti
P
P
D001419:Bacteria / Q000187:drug effects*; D004352:Drug Resistance, Microbial; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology*