[Dominant etiological factors of urinary tract infections in various hospital departments and their resistance to chemotherapeutic agents]. / Czynniki etiologiczne zakazen ukladu moczowego dominujace na róznych oddzialach szpitalnych i ich opornosc na chemioterapeutyki.

PURPOSE: The purpose of this study was the determination of the incidence of urinary tract infection (UTI) in patients hospitalized in specific wards, and the analysis of the factors influencing the incidence of infection. METHODS: 329,608 hospital infection registration cards taken from the Polish national program for registration of hospital infections were analysed. This programme is based on a unified registration card system and on the definitions of particular types of hospital-acquired infections provided by the CDC (Centers for Disease Control, Atlanta, Georgia, USA). Statistical analysis was performed using the Statistica programme. RESULTS: 1,422 cases of hospital-acquired UTI, making up 21% of total hospital-acquired infections, were found. Six hundred sixty-six microbes were isolated from this total number of cases. The dominant pathogens were: Escherichia coli (31%), followed by Pseudomonas aeruginosa (13%), and Enterococcus sp. (12%). Hospital-acquired UTI occurred most often in maternity wards, gynaecology departments and intensive care units. Microbiological confirmation was obtained for only 45% of the clinically diagnosed cases of UTI. A disquieting increase of Pseudomonas aeruginosa resistant to chinolones was observed as well as extremely high resistance to aminoglycosides in Enterococcus sp. CONCLUSIONS: Urinary tract infections (UTIs) are the second most common form of hospital-acquired infection. Causal agents of hospital-acquired UTIs differed, depending upon the specific ward to which the patient is admitted. The most frequently isolated pathogens were Escherichia coli, Pseudomonas aeruginosa and Enterococcus sp. Microbiological confirmation of the clinically diagnosed cases of urinary tract infection is absolutely necessary, as well as a better cooperation between practicing physicians and microbiologists in the detection of hospital-acquired infection and interpretation of results.

Experimental study of mechanical properties of composite carbon screws.

Carbon-carbon composite was used to manufacture carbon screws as possible material for osteosynthesis. The mechanical properties were optimized including the fibre orientation in the composite volume, the effect of the size of the thread and the thread shape. The mechanical properties of the carbon screws were compared with conventional OSTEO steel cortical screws. Two types of carbon specimens were used, varying in fibre orientation along the screw axis. The mechanical properties of the carbon screws including the failure force for one thread and the critical shear stress were determined. The force destroying the connection of the carbon screw with bone was determined. The holding capacity of the carbon screw was compared to the steel screw. The extraction tests demonstrated 50% less holding force than the OSTEO steel screw.