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N Kosakai

Publications and source records attributed to N Kosakai.

At least 37 records · Page 2Linked to original sources

[A nationwide study of the antimicrobial susceptibility of clinical isolates of Staphylococcus aureus in Japan].

We described antimicrobial susceptibilities of clinical isolates of Staphylococcus aureus in 1985 and also a 6-year survey of changing patterns of their susceptibilities to ampicillin (ABPC), cefazolin (CEZ), cefmetazole (CMZ) and gentamicin (GM) from 1980 to 1985 in 103 hospitals. The MICs were determined by the standard method of the Japan Society of Chemotherapy. Among 2,891 isolates in 1985, ratios of resistant strains to ABPC and GM were 24% and 29%, respectively, and those to CEZ and CMZ were 8% and 3%, respectively. Gradual increases in numbers of resistant strains to ABPC, CEZ and CMZ were observed until 1984 but a trend for decreases in numbers of resistant strains to the above 3 antibiotics was observed in 1985. A continuous rise in numbers of resistant strains to GM until 1985 was noted. Isolates from clinical materials such as pus, bile, and urine showed higher incidences of resistance to ABPC and GM than those from sputum, secreta and throat swab. Rates of resistant strains to CEZ were the highest in isolates from bile, pus, sputum and urine. Rates of resistant strains to CMZ were the highest in isolates from bile, and decreased in isolates from sputum, urine and pus in this order. Rates of resistant isolates from inpatients to the 4 antibiotics tested were greater than those from outpatients.

Anti-Bacterial Agents↗

[Susceptibility of bacteria isolated from patients with lower respiratory tract infections to antibiotics (1985)].

Collaborated studies on species of respiratory tract infection (RTI)-related organisms for their identification and drug susceptibilities have been carried out since 1981 at about 20 centers in Japan. On this occasion, the data obtained between 1982 and 1985 were reanalyzed to determine whether or not drug susceptibilities differed depending upon diseases, from which the organisms were isolated. The results summarized below were obtained in this study. 1. Among Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae and Pseudomonas aeruginosa examined, differences in drug susceptibilities according to different diseases were found among S. aureus and also mucoid strains of P. aeruginosa. 2. Susceptibility to beta-lactam antibiotics was definitely lower in S. aureus strains isolated from pneumonia than in those isolated from chronic bronchitis and bronchiectasia. 3. The isolation frequency of methicillin-and cefazolin-resistant strains of S. aureus was 30.3% and 25.9%, respectively, and was especially high among strains isolated from pneumonia. The antibiotic potency of minocycline against S. aureus, including methicillin resistant S. aureus, was the strongest among 9 drugs examined; S. aureus maintained relatively sufficient sensitivity to dicloxacillin among beta-lactam antibiotics. 4. Mucoid producing strains of P. aeruginosa isolated from chronic bronchitis had slightly lower drug susceptibility than those isolated from bronchiectasia. 5. When drug susceptibilities of H. influenzae were compared among groups separated according to diseases using MIC50, MIC80 and MIC90 as indicators, there were no clear differences. The isolation frequency of ampicillin (ABPC)-resistant strains, however, was clearly different among diseases; namely, resistant strains were the most and the least frequently isolated from chronic bronchitis and from pneumonia, respectively. In addition, the drug susceptibility of H. influenzae isolated in 1985 was analyzed in relation to the production of beta-lactamase. As a result, it was suspected that some factors, other than beta-lactamase, participated in the mechanism of ABPC-resistance. 6. These results suggest that drugs to be used for the chemotherapy of RTI should be selected considering the fact that drug susceptibilities of the pathogens differ, even among the same species, according to diseases.

Bacteria↗

[Susceptibility of bacteria isolated from the patients with lower respiratory tract infections to antibiotics (1985)].

It has been more than 4 years since third-generation cephems were introduced into clinical practice. The range of our drug selection definitely tends to increase, because we today have more antibiotics with wider spectrum, antibiotics with strong activities only against Gram-negative strains, such as monobactams, and those with tremendously high activities such as quinolone carboxylic acid derivatives, in comparison to those we had in the past. Among isolates obtained mainly from sputa of 567 patients with lower respiratory tract infections at 16 institutions throughout Japan between September of 1985 and March of 1986, 741 strains were determined to be causative organisms. MIC's of various antimicrobial agents were determined against 67 strains of Staphylococcus aureus, 100 strains of Streptococcus pneumoniae, 199 strains of Haemophilus influenzae, 92 strains of non-mucoid Pseudomonas aeruginosa, 40 strains of mucoid P. aeruginosa, 29 strains of Klebsiella pneumoniae, 10 strains of Escherichia coli and for 42 strains of Branhamella catarrhalis out of the above 741 strains to determine their drug sensitivities. As for types of lower respiratory tract infections found in 1981--1983, 57.9--64.5% of the infections were chronic respiratory infections; i.e., chronic bronchitis, chronic bronchiolitis and bronchiectasis. These chronic infections, including diffuse panbronchiolitis (DPB), were found in 63.1% of lower respiratory tract infections in 1984. Their incidence dropped to 54.0% in 1985, even though DPB was included; i.e., the incidence of chronic bronchiolitis was 5.5%, that of DPB was 7.1%, and that of bronchial asthma associated with lower respiratory tract infections in 1985 was 8.8% which was twice as much as that found in 1981--1984. Although bacterial pneumonia was found in 24.8% of all the cases in 1981, its incidence was reduced to 11.0% in 1983, 15.1% in 1984, and 17.6% in 1985. This reduction seemed to have resulted from gradual decreases in the occurrence of bacterial pneumonia among the young population. As with usual years, a high incidence rate in a total lower respiratory tract infections in 1985 was found among older patients; namely, 73.5% was at the age of 50 or over (417/567). Next, we determined relationships between clinical isolates and isolates from respiratory infections, including chronic bronchitis, chronic bronchiolitis, bronchiectasis and DPB. H. influenzae was isolated from 50.5% of patients with these infections in 1981; however, the detection rate decreased by about 20% to 29.7% in 1985. P. aeruginosa was consistently isolated, between 24.1% and 30.4% every year.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). II. Background of patients].

We have investigated relationships between patients' backgrounds and isolates from urinary tract infections in reference to various conditions, such as sexes, age distribution by sex, species of causative organisms by sex, age distribution according to species and types of infections, species and infections before and after treatment with antibacterial agents, and species and detected places. As for the relationship between sexes and types of infections, although simple urinary tract infections were consistently found at about 20% in men and at about 80% in women between 1981 and 1983, these infections were seen at 24.4% in men and at 75.6% in women in 1984, and at 26.6% and at 73.4% in 1985, indicating slight decreases in the ratio of women. By contrast, complex urinary tract infections were found in men at about 60-70% from 1981 up to 1985, regardless of the presence or absence of indwelling catheter. There were no noticeable changes according to age during this 5-year period in incidences of infections including simple urinary tract infection and complex urinary tract infection with or without indwelling catheter. Thus, backgrounds of patients with urinary tract infections, including sex, age and simple or complex infections, were fairly consistent throughout this period, while there were relatively large changes in species of isolates. Enterococcus faecalis was isolated at about 8% of both men and women in 1982 and 1983, but its isolation rates were increased to 22.5% of men and 17.9% of women in 1984. In 1985 this species was isolated in 14.9% of men and 7.6% of women, and in 11.2% of all patients. Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus spp. and Enterococcus spp. were detected at rates of 3.2%, 8.1%, 0.7% and 1.0%, respectively, and 24.2% of isolated strains were Gram-positive organisms. When species of isolates before treatment with antibacterial agents and their isolation rates were analyzed, it was found that the isolation rate of E. faecalis increased dramatically in 1983, and that this tendency was still seen in 1984. The isolation rate of Gram-positive organisms was 25% in 1984 and 24.3% in 1985. Escherichia coli was consistently isolated at about 40%, but, as far as simple urinary tract infections are concerned, its isolation rate decreased by about 10% in 1985, compared to 1982 and 1983. These results suggested that causative organisms for simple urinary tract infections became similar to those for complex urinary tract infections. In other words, isolates obtained from complex urinary tract infections before treatment were similar to those of simple infections.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). I. Susceptibility distribution].

The results of determinations of sensitivities of bacterial strains to various antibiotics are summarized as follows: 1. Against Escherichia coli, ofloxacin (OFLX) showed the strongest activity among oral antibacterial and antibiotic agents. Its MIC90 was below 0.10 micrograms/ml. The next strongest activity was found in mecillinam (MPC), cefaclor (CCL) and pipemidic acid (PPA); MIC90's of these agents 3.13 micrograms/ml. Cefotiam (CTM), cefotaxime (CTX), ceftizoxime (CZX), cefmenoxime (CMX) and latamoxef (LMOX) had MIC90 below 0.39 micrograms/ml. MIC90's of cefmetazole (CMZ) and cefoperazone (CPZ) were 1.56 micrograms/ml. Aztreonam (AZT) and carumonam (CRMN) in the monobactam group showed strong activities with MIC90's at 0.20 micrograms/ml. 2. Although Klebsiella pneumoniae had a strong resistance to ampicillin (ABPC) and showed relatively low sensitivities to other oral antibacterial and antibiotic agents, OFLX maintained high activity against this species and showed MIC90 of 0.39 micrograms/ml. Among injectable antibiotics, third generation cephems showed the strongest activity to this species with MIC90 of CZX below 0.10 micrograms/ml, of CTX and CMX 0.20 micrograms/ml, and of LMOX 0.78 micrograms/ml. MIC90 of CPZ was 6.25 micrograms/ml, which was the same as those of cefazolin (CEZ) and cefoxitin (CFX). CTM had similar MIC90 to LMOX, namely, 1.56 micrograms/ml. MIC90 of CMZ was 3.13 micrograms/ml. Monobactams AZT and CRMN showed strong activities to this species; their MIC90's were below 0.10 micrograms/ml and 0.20 micrograms/ml. 3. Although Citrobacter freundii generally exhibited low sensitivities to antibacterial and antibiotic agents examined, it showed high sensitivity to OFLX, at MIC80 of 0.78 micrograms/ml. This species showed low sensitivities to MPC, nalidixic acid (NA), PPA, and sulfamethoxazole-trimethoprim (ST). Among injectable antibiotics, LMOX and CMX had activities against this species; namely, MIC80's were 6.25 and 3.13 micrograms/ml, respectively. Among monobactams, AZT showed MIC80 of 12.5 micrograms/ml, and CRMN had that of 6.25 micrograms/ml. 4. Against Enterobacter cloacae, the strongest antibacterial activity was found with OFLX which had MIC90 of 0.39 micrograms/ml. A relatively strong activity was seen with MPC. MIC80 of MPC was 1.56 micrograms/ml. Except to CTM, this species had poor sensitivities to injectable first and second generation cephems, and their MIC80's were over 200 micrograms/ml. MIC80 of CTM was 25 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). III. Secular changes in susceptibility].

Sensitivities to antimicrobial agents of Escherichia coli, Klebsiella spp., Citrobacter spp., Enterobacter spp., Proteus spp., Pseudomonas aeruginosa and Serratia marcescens isolated from infected patients were evaluated and compared according to the types of their infections, i.e., simple and complicated urinary tract infections with or without indwelling catheter. There were no apparent decreases in the sensitivity of E. coli isolated from patients with simple urinary tract infections. When data obtained in 1982-1985 were summarized, it was found that a new quinoline derivative, ofloxacin (OFLX), showed the strongest activity among oral antimicrobial and antibiotic agents. This agent inhibited 100% of bacterial growth at MIC of 1.56 micrograms/ml. The next strongest activity was found with mecillinam (MPC) which showed 89.3% growth inhibition at the same concentration. Cefaclor (CCL) also showed 84.9% growth inhibition at the same concentration. When sensitivities of E. coli isolated from patients with complicated urinary tract infections with or without indwelling catheter to first and second generation cephems were determined, cefotiam (CTM), which inhibited 88.9%: 91.4% bacterial growth at MIC of 0.39 micrograms/ml, had the strongest activity among CTM, cefazolin (CEZ), cefoxitin (CFX) and cefmetazole (CMZ). Among third generation cephems, including cefmenoxime (CMX), latamoxef (LMOX), ceftizoxime (CZX), cefotaxime (CTX) and cefoperazone (CPZ), the strongest activity was observed with CZX, and the agent having the next strongest activity was CMX. LMOX and CPZ showed relatively low activities. Carumonam (CRMN) and aztreonam (AZT), monobactams, showed strong activities against E. coli. As for Klebsiella spp., activities of pencillins against these strains were low. When activities of oral cephems (cephalexin (CEX) and CCL) and of a quinoline derivative OFLX against these strains were determined, OFLX showed strong activity; i.e., the growth of Klebsiella spp. isolated from complicated urinary tract infections was inhibited at 87.2%: 82.1% at MIC of 0.20 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

[Nationwide study of the antimicrobial susceptibility of clinical isolates of Proteus group in Japan].

We discussed the antimicrobial susceptibilities of Proteus group isolated in 1983 and 1984 and also the annual changes of the susceptibilities from 1980 to 1984. The tested strains were isolated in 103 hospitals in Japan. Antibiotics tested for this study were ampicillin (ABPC), cefazolin (CEZ), cefmetazole (CMZ), and gentamicin (GM). The MIC's were determined by the standard method of the Japan Society of Chemotherapy. Susceptibilities of the bacterial strains to the 4 antibiotics were described below: 1. Proteus mirabilis had good susceptibilities to all the antibiotics tested. 2. Susceptibilities of Proteus vulgaris were low to ABPC and CEZ, but high to CMZ and GM. 3. Proteus morganii showed low susceptibilities to ABPC and CEZ, and moderate to CMZ and GM. 4. Susceptibilities of Proteus rettgeri were low to ABPC and CEZ, and 25-40% of the strains were resistant to CMZ and GM. 5. Proteus inconstance had low susceptibilities to ABPC and CEZ, but fairly good to CMZ. About 55% of the strains showed resistance to GM. 6. There were no significant annual changes in susceptibilities of P. mirabilis, P. vulgaris and P. morganii to ABPC, CEZ and CMZ during the period from 1980 to 1984, but decreased susceptibilities to GM were noted in 1982. 7. There was no evidence of changes in susceptibilities of strains of P. rettgeri to ABPC and CMZ, but a tendency of decreasing susceptibilities to CEZ was shown from 1981. 8. P. inconstance showed no major changes in susceptibilities to ABPC, CMZ and GM. 9. Frequencies of resistant strains with MIC of 25 micrograms per ml or more in P. mirabilis, P. morganii and P. rettgeri were higher in 1982 and/or 1983 than the other years.

Ampicillin↗

[Susceptibility of bacteria isolated from the patients with lower respiratory tract infections to antibiotics (1984)].

Bacterial isolates from patients with pulmonary infections have been collected over the last 4 years in collaboration with investigators at 14 hospitals in various parts of Japan to study isolation frequency of pathogens from patients and drug susceptibilities of these isolates. Possible causative pathogens mainly isolated from sputum of patients with lower respiratory tract infections were collected during a period from September 1984 to March 1985. We first determined types of respiratory diseases and found that, between 1981 and 1983, 57.9 approximately 64.5% of the examined diseases were chronic respiratory infections such as chronic bronchitis, chronic bronchiolitis and bronchiectasis, and that these infections including diffuse panbronchiolitis accounted for 63.1% in 1984. Bacterial pneumonia was found to be 24.8% in 1981, but it was 11.0% in 1983 and 15.1% in 1984. These results seemed to reflect decreases in the occurrence of bacterial pneumonia in young population. We then investigated the correlations between these infections and isolates and found that distributions of causative organisms of chronic bronchitis and bronchiectasis during the 4 years were similar while the detection rate of Staphylococcus aureus from bacterial pneumonia increased in 1982 and 1983, and that of Gram-positive organisms such as Enterococcus faecalis rose in 1984. Branhamella catarrhalis was considered to be a non-pathogenic organism normally harbored in the upper respiratory tract. Recently, however, respiratory infections caused by this organism have been reported by some investigators. In our research also, this Gram-negative diplococcus was isolated as a causative organism of respiratory infections as 6 strains were found in 1983 and 29 strains in 1984, hence an increase was observed.

Adult↗

Evaluation of direct and rapid identification of group A streptococci from throat swabs by Culturette 10-Minute Group A Strep ID test kit.

The Culturette Brand 10-Minute Group A Strep ID test kit (Marion Scientific, Division of Marion Laboratories, Inc., Kansas City, Mo.) was evaluated for its sensitivity and specificity in identifying the group A streptococci directly from 96 throat swabs, against the conventional culture method and serological grouping test. Our results indicated that the rapid test kit and conventional method are 93.8% accurate; percent sensitivity and specificity of the rapid test was 80.6% and 100%, respectively. None of the false-positive observed in rapid test kits occurred with the heterogeneous microorganisms. More than 8 X 10(4) colony forming unit per swab was required for the positive latex agglutination of the test kit. Since the Culturette method is simple to perform and correctly identifies group A streptococcal antigen, and also required no special instruments, it appears to be applicable in hospital laboratories and outpatients clinics.

Bacteriological Techniques↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). I. Susceptibility distribution].

Our research group was engaged for 3 years (1979-1981) in a study on sensitivities to antibiotics of 4 bacterial groups including representative pathogenic bacteria found in cases of urinary tract infections; i.e. E. coli, Klebsiella spp., Citrobacter spp., and Proteus spp. Since 1982, all the bacterial strains isolated by our group from patients with urinary tract infections and deemed by doctors in charge as pathogens were sent to the Laboratory of Clinical Pathology of Juntendo University, where they were refixed and subjected to MIC determination. This is the third year of the new study. E. coli was detected most frequently from patients with urinary tract infections and the detection frequency was 28% (323/1,153) this year (1984), whereas it was 35.3% (304/860) last year, showing a 7% decline from last year to this year. E. faecalis was next frequent organism (12.7% or 147/1,153) followed by P. aeruginosa (10.8% or 124/1,153). This order, however, was reversed from last year. Other pathogens, in a decreasing order of isolation frequencies following the above three, were as follows: Proteus spp. (9.5% or 109/1,153), S. marcescens (6.2% or 71/1,153), S. epidermidis (5.4% or 62/1,153), K. pneumoniae (4.9% or 56/1,153), Enterobacter spp. (2.4% or 28/1,153) and Citrobacter spp. (2.3% or 27/1,153). The results of the determination of the sensitivity of bacterial strains to the antibiotics are described below. Of all the oral antibacterial and antibiotic agents used against E. coli, mecillinam (MPC), cefaclor (CCL) and pipemidic acid (PPA) proved to have high antibacterial potency, and their MIC90 (the concentration to inhibit growths of 90% of the objective bacteria) was 3.13 micrograms/ml. The MIC90's of cefotiam (CTM), cefotaxime (CTX), ceftizoxime (CZX), cefmenoxime (CMX) and latamoxef (LMOX) were less than 0.39 microgram/ml. The MIC90's of cefmetazole (CMZ) and cefoperazone (CPZ) were invariably 1.56 micrograms/ml. K. pneumoniae was not sensitive to ampicillin (ABPC) and did not show much sensitivity to other oral antibacterial and antibiotic agents also. Of all the injectable preparations of antibiotics, cephem antibiotics of the third generation showed the most potent antibacterial effects against K. pneumoniae, and their MIC90's were lower than 0.10 microgram/ml for CZX, 0.20 microgram/ml for CTX, 0.39 microgram/ml for CMX, and 0.78 microgram/ml for LMOX, while MIC90's of CPZ was 6.25 micrograms/ml, which was equal to that of CMZ. The MIC90 of CTM was 0.78 microgram/ml which was identical to that of LMOX.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). III. Secular changes in susceptibility].

Cases with infections of urinary tracts were divided into 3 groups of the simple infections, and complicated infections without indwelling of catheter, and complicated infections with indwelling of catheter. Susceptibilities to antimicrobial agents of Escherichia coli, Klebsiella spp., Proteus spp., Citrobacter spp., Enterobacter spp., Pseudomonas aeruginosa and Serratia marcescens which were isolated from patients with these infections were determined. There was no tendency of decline in the susceptibilities of E. coli isolated from the patients with simple urinary tract infections (UTI). Susceptibilities of E. coli isolated from the patients with complicated UTI without and with indwelling of catheter to cephem antibiotics of the third generation were examined. The susceptibility of E. coli strains isolated from patients with complicated UTI without and with indwelling of catheter remained the same. More specifically, cefmenoxime (CMX) at a concentration of less than 0.10 microgram/ml inhibited the growth of E. coli isolated from cases without: with catheter at 74.1%: 78.3% in 1982, 75.4%: 73.3% in 1983, and 81.3%: 84.8% in 1984. Also, ceftizoxime (CZX) at a concentration of less than 0.10 microgram/ml inhibited the growth at 83.3%: 95.7% in 1982, 89.2%: 86.7% in 1983, and 91.7%: 97.0% in 1984. Latamoxef (LMOX) at less than 0.10 microgram/ml inhibited the growth at 59.3%: 43.5% in 1982, 47.7%: 40.0% in 1983, and 47.9%: 42.4% in 1984. The antibacterial effect of penicillin against Klebsiella spp. was found to be poor, while those of oral cephem antibiotics, cephalexin (CEX), cefaclor (CCL), and cefazolin (CEZ) which is the cephem antibiotics of the so-called first generation and cefotiam (CTM) among other cephem antibiotics of the so-called second generation were relatively good. A study of susceptibilities of Klebsiella spp. isolated from patients with complicated UTI without and with indwelling of catheter revealed inhibition of growth by CTM at a concentration of 0.39 microgram/ml at 84.0%: 75.9% in 1982, 70.6%: 75.0% in 1983, and 95.8%: 77.8% in 1984. Cefmetazole (CMZ) at a concentration of 0.39 microgram/ml showed a relatively lower rate of growth inhibition of Klebsiella spp., while at 0.78 microgram/ml it inhibited the growth at 88.0%: 72.4% in 1982, 52.9%: 50.0% in 1983, and 70.8%: 66.7% in 1984. The antibacterial effects of both CTM and CMZ against Klebsiella spp. isolated from patients with indwelling of catheter were found to be poor, and some of the bacterial strains showed a MIC over than 100 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

[A nationwide study of the antimicrobial susceptibility of clinical isolates of Klebsiella sp. in Japan].

We have reported the antimicrobial susceptibility of clinical isolates of Escherichia coli in 1983 and 1984 to 4 antibiotics, ampicillin (ABPC), cefazolin (CEZ), cefmetazole (CMZ) and gentamicin (GM), in the previous report. In this paper, we described the antimicrobial susceptibility of Klebsiella sp. to the same antibiotics during the same period reported for E. coli before. Numbers of isolates tested were 1,671 strains in 1983 and 1,374 strains in 1984. We determined MICs of the 4 antibiotics against isolates by the standard method of the Japan Society of Chemotherapy. The most effective agent was GM among the 4 antibiotics. CMZ had a similar antimicrobial activity to GM. Resistance rates were low for both agents. CEZ had a fairly good antimicrobial activity, but it was less active than GM and CMZ. ABPC was not effective. There was neither significant annual change of antimicrobial activity of each agent against isolates nor an increasing tendency of resistant strains in the last 5 years. Depending on isolates from clinical materials, differences in the susceptibility were noted and there was a high ratio of resistant organisms among isolates from urine.

Ampicillin↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). II. Background of patients].

Groups of bacteria were isolated from patients with infections of urinary tracts, and backgrounds of these isolates and patients have been studied in terms of the sexual distribution, and distributions of sexes versus age of the patients relationships between bacterial types and sexual and age distribution of the patients from whom the isolates were obtained correlation ages of patients and types of infections, the association of certain types of bacteria with certain infections and the effect of antibacterial treatments on these types of bacteria, approximately 20% of simple infections of urinary tracts occurred in males and approximately 80% in females on average from 1981 to 1984. This ratio showed hardly any changes during this period. Likewise, male patients comprised approximately 60-70% of all the cases with complicated infections of urinary tracts regardless of indwelling or without indwelling of catheters. In terms of age, the ratio of urinary tract infections was almost universally observed, e.g., for patients in 40's: 10.0% in 1981, 11.0% in 1984, while in those in 70's: 25.5% and 21.2%, respectively. Consequently, background factors of the cases with infections of urinary tracts, such as sexes, age, or simple or complicated, remained almost stable, whereas bacteria involved showed considerable variations. In 1982 and 1983, the frequency of isolations of Enterococcus spp. was approximately 8% in both males and females. However, in 1984, the frequency of isolation of Enterococcus spp. was 22.5% in the males 17.9% in the females. The frequency of isolation of Enterococcus spp. increased in all age groups, but the frequency was not particularly high among the aged. A study on variations and isolation frequencies of bacteria before the administration of antibiotic agents revealed that isolation frequencies of Enterococcus spp. sharply increased in 1983, and this high frequency remained in 1984. The frequency of isolation of E. coli tended to decrease year after year. This finding represents that the frequency of isolations of E. coli from materials of cases with simple infections of urinary tracts has decreased, showing that pathogenic bacteria from simple infections of urinary tracts were becoming similar to that of the complicated infections of urinary tracts. These findings seem to be worth mentioning here. In cases receiving administrations of antibacterial and antibiotic agents for more than 8 days. Frequencies of isolation from cases without catheter retention and from those with catheter retention were similar.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

[A nationwide study of the antimicrobial susceptibility of clinical isolates of Escherichia coli in Japan].

We studied the antimicrobial susceptibility of E. coli isolated in 1983 and 1984 and also the yearly changes of the susceptibility of E. coli from 1980 to 1984 isolated in 103 hospitals in Japan. Antibiotics used for MIC determination were ampicillin (ABPC) as a penicillin, cefazolin (CEZ) as a cephalosporin, cefmetazole (CMZ) as a cephamycin and gentamicin (GM) as an aminoglycoside. Numbers of isolates tested were 2,321 strains in 1983 and 1,965 strains in 1984. CMZ was the most effective agent among the 4 antibiotics tested, followed by GM and CEZ in this order. A large number of the isolates were inhibited by 1.56 micrograms/ml on CMZ and GM and by 6.25 micrograms/ml of CEZ. About two-thirds of the isolates were inhibited at a concentration of 12.5 micrograms/ml or less of ABPC. The susceptibility of E. coli against the 4 antibiotics changed little year by year and the tendency of the appearance of resistant strains did not increase in the last 5 years.

Ampicillin↗

In vitro susceptibility of Pseudomonas maltophilia to antimicrobial agents.

Reports on the isolation and pathogenicity of some species of Gram-negative and glucose-nonfermentative bacilli have appeared in the literature since 1962. The infections caused by those organisms have become important problems as an opportunistic infection in immunosuppressed patients. Pseudomonas maltophilia is a glucose-nonfermentative aerobic Gram-negative rod widely dispersed in nature. The role of Pseudomonas maltophilia as an opportunistic pathogen is not thoroughly established, but a few papers on clinical infections associated with P. maltophilia have been published. P. maltophilia is considerably less susceptible to certain of the most commonly-used antibiotics. We have reviewed the susceptibilities of P. maltophilia to antimicrobial agents currently available and yearly changes of the strains in resistance to the antibiotics that have been extensively used.

Anti-Bacterial Agents↗