[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). I. Susceptibility distribution].

The bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of them to many kinds of antimicrobial agents were investigated. Of them, 701 strains were estimated as prophlogistic bacteria and used for the investigation. The strains consisted of 258 Gram-positive bacterial strains (36.8%) and 443 Gram-negative bacterial strains (63.2%). Against Staphylococcus aureus, vancomycin (VCM) showed the strongest activity and prevented the growth of all strains with 2 microg/mL. Against Streptococcus agalactiae, ampicillin (ABPC), cefozopran (CZOP), imipenem (IPM), and clarithromycin (CAM) showed a strong activity and the MIC90 was 0.125 microg/mL or less. Against Enterococcus faecalis, VCM, ABPC, and IPM showed a strong antibacterial activity. The antibacterial activity of cephems to Escherichia coli was generally good, and especially CZOP and cefpirome (CPR) showed the strongest activity (MIC90: < or = 0.125 microg/mL). Quinolone resistant E. coli [MIC of ciprofloxacin (CPFX): > or =4 microg/mL] was detected at frequency of 15.7%, which was higher than that in the last year. Against Klebsiella pneumoniae, meropenem (MEPM) showed the strongest activity and next, the antibacterial activity of CRMN and CZOP was good. The antibacterial activity of the other cephems, however, significantly decreased, compared with that evaluated in last year. Against Serratia marcescens, MEPM had the strongest antibacterial activity. Against Proteus mirabilis, MEPM and CRMN showed the strongest activity and prevented the growth of all strains with 0.125 microg/mL or less. Nest, cefmenoxime (CMX), ceftazidime (CAZ), cefixime (CFIX), cefpodoxime (CPDX), CPR, CZOP, and cefditoren (CDTR) showed a strong activity. The antibacterial activity of the drugs to Pseudomonas aeruginosa was generally low, and MIC90 of all the drugs was ranged from 32 to < or = 256 microg/mL except IPM and amikacin (AMK) having 16 microg/mL. The antibacterial activity of CZOP was relatively good (MIC50: 2 microg/mL).

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). II. Background of patients].

Seven hundred and nineteen bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2002 and July 2003. The frequency of bacteria isolation divided with patient clinical background was compared. The clinical background investigated included sex, age, type of infections, timing of antibiotics administration, and presence or absence of surgery affecting a decrease in defense against infection. The bacterial strains were divided with the age and sex of the patients and the types of infections. In males, the number of patients aged less than 50 years was few and the complicated UTIs without indwelling catheter was observed most frequently. Number of patients aged 20-39 years was greater in female than male. In all of ages except 0-9 and 70-79 years, the ratio of the uncomplicated UTIs was high, accounting for 44.4-91.7% of all types of infections. In the present time, the bacteria most frequently isolated were Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis also were relatively frequently isolated. E. coli was most frequently isolated from the uncomplicated UTIs, and P. aeruginosa and E. faecalis were frequently isolated from the complicated UTIs with indwelling catheter. With respect to the relation of these results to the age of the patients, in the uncomplicated UTIs, the isolation frequency of E. coli was the highest in all age groups, accounting for 40% or higher. In the complicated UTIs without indwelling catheter, the isolation frequency of E. coli decreased with aging of the patients but still was the highest in all age groups. In the complicated UTIs with indwelling catheter, the isolation frequency of E. coli was lower than in the uncomplicated UTIs in all age groups and P. aeruginosa and E. faecalis were more frequently isolated. In comparison of causative bacteria in UTIs between before and after the administration of antibiotics, P. aeruginosa increased after the administration in any types of UTIs. In comparison of causative bacteria in UTIs with or without surgery, E. coli was more frequently isolated in the patients without surgery, while P. aeruginosa and E. faecalis were more frequently isolated in the patients with surgery in any UTIs.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2003). III. Secular changes in susceptibility].

The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from 565 patients diagnosed as urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of these bacteria to various antimicrobial agents were examined. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1994 and 2002. The drug sensitivity of S. aureus in this year was similar to those in up to the previous years and S. aureus showed the best susceptibility to vancomycin. The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous years. The drug sensitivity of E. coli in this year was generally good except penicillins and was similar to those in up to the previous years. Among cephems, cefozopran (CZOP) and cefpirome (CPR) showed the highest potency activity (MIC90: < or = 0.125 microg/mL). An antibacterial activity of cefotiam (CTM) was stable for 10 years and was fine (MIC0: < or = 0.5 microg/mL). The sensitivity of E. coli to carbapenems and carumonam (CRMN) also was good like to CZOP. The sensitivity of the complicated UTIs group to quinolones, however, has decreased after 2000 and it was suggested that the resistance to the drug has developed. Kiebsiella spp. showed a decrease in the susceptibility to some of cephems. The drugs indicating a big decrease in the sensitivity were cefazolin, CTM, cefaclor, and cefpodoxime. Imipenem, carbapenems, also indicated a decrease in the sensitivity. The susceptibility of the strain to the other drugs was similar to that in up to the previous years. Among them, CZOP maintained good susceptibility (MIC90: > or = 0.125 microg/mL against uncomplicated UTIs, 0.25 microg/mL against complicated UTIs) like meropenem. The drug sensitivity of P. aeruginosa was generally low and was not much different from that in up to the previous years.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2002). III. Secular changes in susceptibility].

The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as urinary tract infections (UTIs) in 13 institutions in Japan were supplied between August 2002 and July 2003. The susceptibilities of these bacteria to various antimicrobial agents were examined. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1993 and 2001. The drug sensitivity of S. aureus in this year was similar to those in up to the previous year and S. aureus showed the best susceptibility to vancomycin. The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous year. The drug sensitivity of E. coli in this year was generally good except penicillins and was similar to those in up to the previous year. Among cephems, cefozopran (CZOP) and cefpirome (CPR) showed the highest potency (MIC90: < or = 0.125 microg/mL). An antibacterial activity of cefotiam (CTM) was similar to it in 10 years ago and was fine (MIC90: < or = 1 microg/mL). The sensitivity of E. coli to carbapenems and carumonam (CRMN) also was good like to CZOP. However, the sensitivity of the complicated UTIs group to quinolones decreased after 2000 and was suggested to develop the resistance to the drug. The drug sensitivity of Klebsiella spp. in this year also was similar to those in up to the previous year. The bacteria showed good susceptibility (MIC: < or = 0.125 microg/mL) to cefmenoxime (CMX), CPR, cefixime (CFIX), flomoxef (FMOX), and CZOP among cephems. The drug sensitivity of P. aeruginosa was generally low. Most of the bacteria were little sensitive to cephems except CZOP and ceftazidime (CAZ). The sensitive bacteria to CZOP and ceftazidime (CAZ) were observed to be 26.8% (15/56 strains) and 39.3% (22/56 strains) in complicated UTIs group, respectively. The sensitivity profile of P. aeruginosa to the other tested drugs was not much different from that in up to the previous year. However, the sensitivity of the bacteria to carbapenems tended to decrease after 2000, and the low sensitive strains (MIC: > or = 256 microg/mL) were detected at 22.2% (2/9 strains) in the uncomplicated UTIs group and 3.6% (2/56 strains) in the complicated UTIs group.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2002). I. Susceptibility distribution].

The bacterial strains isolated from 491 patients diagnosed as having urinary tract infections (UTIs) in 13 institutions in Japan were supplied between August 2002 and July 2003. The susceptibilities of them to many kinds of antimicrobial agents were investigated. Of them, 578 strains were estimated as causative bacteria and used for the investigation. The number of them was 578 strains consisting of 177 gram-positive bacterial strains (30.6%) and 401 gram-negative bacterial strains (69.4%). Against Staphylococcus aureus, vancomycin (VCM) showed a strong activity and prevented the growth of all strains with 1 microg/mL. The susceptibility of Staphylococcus epidermidis to cephems including cefotiam (CTM) was relatively good. Against Enterococcus faecalis, ampicillin (ABPC), imipenem (IPM), and VCM showed the strongest antibacterial activity (MIC90: 2-4 microg/mL). In addition, the low sensitive strains (MIC: > or = 256 microg/mL) to clarithromycin (CAM) were detected at 48.3% but none to cefozopran (CZOP). The antibacterial activity of cephems to Escherichia coli was generally good, and especially CZOP and cefpirome (CPR) showed the highest activity (MIC90: < or = 0.125 microg/mL). Quinolone resistant E. coli was detected at frequency of 13.5%, which was higher than that in the last year. The antibacterial activity of cephems to Citrobacter freundii was generally low but CZOP and CPR had a strong acitivity (MIC90: 0.25 and 0.5 microg/mL, respectively). The antibacterial activity of cephems to Klebsiella pneumoniae was good and especially cefmenoxime (CMX), cefixime (CFIX), flomoxef (FMOX), CPR, and CZOP showed stronger activity (MIC90: < or = 0.125 microg/mL). Against Serratia marcescens, meropenem (MEPM) had the highest antibacterial activity followed by CPR and CZOP. Against Proteus mirabilis, CMX, ceftazidime (CAZ), CPR, MEPM, carumonam (CRMN), and levofloxacin (LVFX) showed the strongest activity (MC90: < or = 0.125 microg/mL). Among other cephems, CZOP and CFIX were also strong (MIC90: 0.25 microg/mL). The antibacterial activity of the drugs to Pseudomonas aeruginosa was generally low, and MIC90 of all the drugs were ranged from 64 to > or = 256 microg/mL except IPM and amikacin (AMK) having 16 microg/mL. The antibacterial activity of CZOP was relatively good (MIC50: 8 microg/mL).

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2002). II. Background of patients].

A total of 615 bacterial strains isolated from 491 patients diagnosed as having urinary tract infections (UTIs) in 13 institutions in Japan were supplied between August 2002 and July 2003. Then, the clinical background of patients were investigated such as sex, age, and type of infections and kind of bacteria, frequency of bacteria isolation by age and infections, bacteria and infections by timing of antibiotics administration, and bacteria and infections by surgical procedures. The bacterial strains were divided by the age and sex of the patients and the types of infections. In males, the number of patients aged less than 50 years was few and the complicated UTIs without indwelling catheter was observed most frequently. In the present time, the bacteria most frequently isolated were Escherichia coli. Pseudomonas aeruginosa and Enterococcus faecalis were also relatively frequently isolated. E. coli decreased and P. aeruginosa increased with the complication of the infections. E. faecalis tended to be isolated more frequently in the complicated UTIs than in the uncomplicated UTIs. With respect to the relation of these results to the age of the patients, in the uncomplicated UTIs, the isolation frequency of E. coli was the highest in all age groups, accounting for 70.8% in 20-49 years old. In the complicated UTIs without indwelling catheter, the isolation frequency of E. coli decreased with aging of the patients and was lower than that of E. faecalis in the patients aged 70 or more (18.3 vs 20.6%). In the complicated UTIs with indwelling catheter, the isolation frequency of E. coli was lower than in the uncomplicated UTIs in all age groups and P. aeruginosa and E. faecalis were more frequently isolated. In comparison of causative bacteria in UTIs between before and after the administration of antibiotics, E. coli decreased and P. aeruginosa increased after the administration in any UTIs. In comparison of causative bacteria in UTIs with or without surgery, E. coli was more frequently isolated in the patients without surgery, while P. aeruginosa was more in the patients with surgery in any UTIs. E. faecalis was more frequently isolated in the patients with surgery in uncomplicated and complicated UTIs without indwelling catheter and in the patients without surgery in complicated UTIs with indwelling catheter.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2001). I. Susceptibility distribution].

The bacterial strains isolated from patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between the period of September and December 2001. Then, the susceptibilities of them to a variety of antimicrobial agents were investigated. The number of them were 496 strains. The breakdown of these strains was Gram-positive bacteria as 29.6% and Gram-negative bacteria as 70.4%. Susceptibilities of these bacteria to antimicrobial agents were as follows; against Staphylococcus aureus, vancomycin (VCM) showed a strong activity, and this drug also had a strong activity against MRSA in preventing growth of all strains at 1 microgram/mL. In addition, arbekacin (ABK) showed strong activity with the MIC90 of 2 micrograms/mL against MRSA and prevented growth of all strains at 4 micrograms/mL. ABK also showed a strong activity against Staphylococcus epidermidis in preventing growth of all strains at 0.5 microgram/mL. Ampicillin (ABPC) and cefozopran (CZOP) showed a relatively strong activity against S. epidermidis (MIC90: 8 micrograms/mL). ABPC, imipenem (IPM), and VCM showed strong activities against Enterococcus faecalis. No increase of low-susceptible strains in E. faecalis was observed against these antimicrobial agents. Against Escherichia coli, carbapenems showed the highest activities: meropenem (MEPM) prevented growth of all strains at 0.25 microgram/mL; IPM prevented growth of all strains at 0.5 microgram/mL. CZOP and cefotiam (CTM) also showed strong activities against E. coli: MIC90 of CZOP was within 0.125 microgram/mL; MIC90 of CTM was within 0.5 microgram/mL. Quinolone-resistant E. coli was detected at frequency of 9.3%, which was lower than that in the last year, and was higher level than those in up to 1999. MEPM showed the strongest activity against Citrobacter freundii in preventing growth of all strains at 0.125 microgram/mL. Almost all drugs showed strong activities against Klebsiella pneumoniae and Proteus mirabilis, and MEPM prevented growth of all strains within 0.125 microgram/mL. Against Serratia marcescens, the MIC90 of gentamicin (GM) was the lowest value being 2 micrograms/mL, and those of IPM and carumonam were 8 and 16 micrograms/mL, respectively. Against Pseudomonas aeruginosa, almost all drugs were not so active. The MIC90 of GM was 8 micrograms/mL, those of IPM and amikacin were 16 micrograms/mL, and those of all other drugs were over than 32 micrograms/mL.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2001). II. Background of patients].

Five-hundred thirty one bacterial strains isolated from 412 patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between September and December 2001. Then, the clinical background of patients were investigated such as sex, age, and type of infections, infections and kind of bacteria, frequency of bacteria isolation by age and infections, bacteria and infections by timing of antibiotics administration, and bacteria and infections by surgical procedures. With regard to the relationship between age and sex of patients and type of infections, the number of cases aged lower than 50 years was few and complicated UTIs without indwelling catheter was the most frequent in male patients. In females, the number of patients aged lower than 20 years was few. Most of female patients aged lower than 80 years had uncomplicated UTIs. As for the relationship between type of infections and kind of bacteria, Escherichia coli decreased as the infections were more complicated, and Pseudomonas aeruginosa and Enterococcus faecalis increased as the infections were more complicated. In relation of these results to age of patients, isolation frequency of E. coli gradually decreased with aging in patients aged 20 years and older with uncomplicated UTIs. The isolation frequencies of E. faecalis decreased with aging in the patients with complicated UTIs without indwelling catheter while P. aeruginosa decreased with aging in the patients with complicated UTIs with indwelling catheter. E. coli was isolated a few after administration of antibiotics, and P. aeruginosa and E. faecalis were frequently isolated after administration in the patients with all types of infections. As for type of causative organisms in UTIs and with or without surgical operation, E. coli was frequently isolated in the patients without surgery in the patients with uncomplicated UTIs and complicated UTIs without indwelling catheter, while P. aeruginosa was frequently isolated in the patients who underwent surgery in the patients with uncomplicated UTIs and complicated UTIs with indwelling catheter. In uncomplicated UTIs, isolation frequencies of Klebsiella spp., P. aeruginosa, and E. faecalis were significant in the patients with surgery. In complicated UTIs without indwelling catheter, Klebsiella spp. was frequently isolated in the patients with surgery. In complicated UTIs with indwelling catheter, S. aureus and Staphylococcus spp. were frequently isolated in the patients without surgery.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2001). III. Secular changes in susceptibility].

The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as urinary tract infections (UTIs) in 10 institutions in Japan were supplied between September and December, 2001. Then, the susceptibilities of these bacteria to various antimicrobial agents were examined, and the results were compared with those obtained between 1992 and 2000. Comparison was made by classifying strains isolated from patients into those in uncomplicated UTIs and those in complicated UTIs (including with or without indwelling catheter). The drug sensitivity of S. aureus in this year was comparable to those in up to the previous year, and S. aureus showed the best susceptibility to vancomycin (VCM). E. faecalis showed good susceptibility to ampicillin and imipenem, and the MIC90s were 2 micrograms/mL. The susceptibility of E. faecalis to VCM was also good. E. coli showed good susceptibility to the drugs except penicillins. Among cephems, the susceptibility to cefozopran (CZOP) was better (MIC90: < or = 0.125 microgram/mL). Just as the last report, the decreases in susceptibility of E. coli to quinolones were also observed in the patients with complicated UTIs. The susceptibility of Klebsiella spp. to all the test drugs did not significantly change in 2001 and was generally good but not to penicillins. Among cephems, Klebsiella spp. showed good susceptibility to flomoxef, cefpirome, cefixime, and CZOP with < or = 0.125 microgram/mL of MIC90s either in uncomplicated or complicated UTIs. Although the drug sensitivity of P. aeruginosa was generally low, the detection of the strains that showed good susceptibility to quinolones and carbapenems (MIC: < or = 0.125-2 micrograms/mL) were relatively frequent.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). I. Susceptibility distribution].

The bacterial strains isolated from patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between the period of August 2000 and July 2001. Then, the susceptibilities of them to many kinds of antimicrobial agents were investigated. The number of them were 511 strains. The breakdown of these strains was Gram-positive bacteria as 29.0% and Gram-negative bacteria as 71.0%. Susceptibilities of these bacteria to antimicrobial agents were as follows; vancomycin (VCM), ampicillin (ABPC) and imipenem (IPM) showed strong activities against Enterococcus faecalis. No increase in low-susceptible strains of E. faecalis observed against these antimicrobial agents. VCM showed a strong activity against MRSA preventing growth of all strains with 1 microgram/ml. In addition, the activity of arbekacin (ABK) was strong with the MIC90 of 2 micrograms/ml against MRSA and prevented growth of all strains with 4 micrograms/ml. ABK showed a strong activity against Staphylococcus epidermidis preventing growth of all strains with 0.5 microgram/ml. ABPC, cefotiam (CTM) and cefozopran (CZOP) also showed a relatively strong activity against S. epidermidis (MIC90: 4 to 8 micrograms/ml). Against Escherichia coli, carbapenems showed high activities: meropenem (MEPM) prevented growth of all strains within 0.125 microgram/ml; IPM prevented growth of all strains with 0.25 microgram/ml. CZOP and CTM also showed strong activities against E. coli: MIC90 of CZOP was within 0.125 microgram/ml; MIC80 and MIC90 of CTM were 0.25 and 0.5 microgram/ml, respectively. Quinolone resistant E. coli was detected at frequency of 14.0%, which was significantly higher than that in the last year. Almost all drugs showed strong activities against Klebsiella pneumoniae and Proteus mirabilis, and MEPM prevented growth of all strains within 0.125 microgram/ml. Against Pseudomonas aeruginosa, almost drugs were not so active. The MIC90 of carbapenems and gentamicin (GM) were 16 micrograms/ml and those of all other drugs were more than 32 micrograms/ml. Against Serratia marcescens, the MIC90 of IPM and GM were the lowest value being 2 micrograms/ml, and that of MEPM was 4 micrograms/ml.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). II. Background of patients].

Five-hundred eighty eight bacterial strains isolated from 435 patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between August 2000 and July 2001. Then, the clinical background of patients were investigated such as sex, age, and type of infections, infections and kind of bacteria, frequency of bacteria isolation by age and infections, bacteria and infections by timing of antibiotics administration, and bacteria and infections by surgical procedures. About the relationship between age and sex of patients and type of infections, the number of male patients aged less than 50 years was few, and complicated UTIs without indwelling catheter was the most frequent. In females, the number of patients aged less than 20 years was few. The majority of female patients aged 40 years and over had complicated UTIs while uncomplicated UTIs was most frequent in the patients being twenties. As for type of infections and kind of bacteria, Escherichia coli decreased when the infections became complicated, and pseudomonas aeruginosa increased when the infection became complicated. Enterococcus faecalis was isolated more frequently in complicated UTIs than in uncomplicated UTIs. Considering this result by age of patients, isolated frequency of E. coli was gradually decreased with aging in patients aged 20 years and over with uncomplicated UTIs or complicated UTIs without indwelling catheter. The isolated frequencies of Klebsiella spp., P. aeruginosa, and E. faecalis were high in the patients with complicated UTIs without indwelling catheter. In the patients aged 70 years and over with complicated UTIs with indwelling catheter, P. aeruginosa and E. faecalis were frequently isolated. As for type of causative organisms in UTIs before and after the administration of antibiotics, the isolation of bacteria was remarkably decreased after administration in the patients with uncomplicated UTIs and complicated UTIs without indwelling catheter. E. coli decreased after administration of antibiotics, and P. aeruginosa increased after administration in the patients with all types of infections. As for type of causative organisms in UTIs and surgical procedures, E. coli was frequently isolated in the patients without surgery in all types of infections, while P. aeruginosa was frequently isolated in the patients who underwent surgery. In uncomplicated UTIs, Proteus spp. and E. faecalis were frequently isolated in the patients with surgery. In complicated UTIs without indwelling catheter, Klebsiella spp. was frequently isolated in the patients without surgery and E. faecalis was frequently isolated in the patients with surgery. In complicated UTIs with indwelling catheter, most of organisms except P. aeruginosa and S. aureus were frequently isolated in the patients without surgery.

[Comparative studies on activities on antimicrobial agents against causative organisms isolated from patients with urinary tract infections (2000). III. Secular changes in susceptibility].

The bacteria (Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as having urinary tract infections (UTIs) in 10 institutions in Japan were supplied between August 2000 and July 2001. Then, the susceptibilities of these bacteria to various antimicrobial agents were examined, and the results were compared with those obtained between 1992 and 1999. Comparison was made by classifying strains isolated from patients into those in uncomplicated UTIs and those in complicated UTIs (including with or without indwelling catheter). E. faecalis showed good susceptibility to ampicillin (ABPC) and imipenem (IPM), and the MIC90s were 2 micrograms/ml. Also, E. faecalis showed good susceptibility to vancomycin (VCM). However, the MIC90, which was 2 micrograms/ml between 1992 and 1999, rose to 4 micrograms/ml in patients with complicated UTIs because the strains inhibited at 4 micrograms/ml increased more than before. The low susceptibility of S. aureus to arbekacin (ABK) in complicated UTIs, as shown in 1998 and 1999, recovered in 2000, and no strains inhibited at > or = 4 micrograms/ml were detected. E. coli showed good susceptibility to CTM (MIC90: 0.25-0.5 microgram/ml) and CZOP (MIC90: < or = 0.125 microgram/ml) and was not resistant to those. E. coli also showed good susceptibility to the other drugs except to penicillins. Decreases in susceptibility of E. coli to quinolones, ciprofloxacin (CPFX), and sparfloxacin (SPFX) were observed in the patients with complicated UTIs. The susceptibility of Klebsiella spp. to all drugs did not significantly change in 2000 and was generally good except to penicillins. Although the susceptibility of P. aeruginosa to carbapenems was notable, the MIC90 went up from 4 micrograms/ml to 16 micrograms/ml in complicated UTIs compared with those observed in the previous year.