Nationwide, multicenter survey on the efficacy and safety of piperacillin for adult community-acquired pneumonia in Japan.

A survey on adult community-acquired pneumonia was conducted jointly by multiple centers nationwide to verify the Japanese Respiratory Society Guidelines for the Management of Community-Acquired Pneumonia in Adults (JRS2005). The efficacy and safety of piperacillin (PIPC) were investigated at the same time. PIPC is recommended as the initial treatment for patients with suspected bacterial pneumonia and pneumococcal pneumonia in JRS2005. Overall, 552 and 333 patients were registered for safety and efficacy analysis in this study, respectively. The majority of the cases in which PIPC was used had moderate disease (63.7 %), and the most common daily dosage was 4 g (73.6 %). The efficacy rate was 83.5 % overall, 81.1 % in patients with suspected bacterial pneumonia, and 92.8 % in patients with pneumococcal pneumonia. The efficacy rate with a daily dosage of 4 g was 84.9 %, and the efficacy rates achieved with a daily dosage of 4 g in patients who had mild and moderate suspected bacterial pneumonia were 90.0 and 82.6 %, respectively. The most commonly isolated causative organisms were Streptococcus pneumoniae (S. pneumoniae) and Haemophilus influenzae (H. influenzae), and the bacterial eradication rates were high (97.2 and 100 %, respectively). The incidence of adverse drug reactions was 5.62 %, among which the main events were hepatic dysfunction and decreased white blood cell count. In conclusion, this study showed that PIPC is safe and effective at 4 g/day for mild-to-moderate adult community-acquired pneumonia.

Nationwide survey on the 2005 Guidelines for the Management of Community-Acquired Adult Pneumonia: validation of severity assessment.

INTRODUCTION: The Japanese Respiratory Society Guidelines for the Management of Community-Acquired Pneumonia (CAP) in Adults (JRS 2005) were published to revise the Basic Concept for the Management of CAP in Adults (JRS 2000). Revisions in JRS 2005 mainly focused on the criteria for the assessment of pneumonia severity and the differentiation between bacterial pneumonia and atypical pneumonia. To evaluate the JRS 2005 criteria for the assessment of pneumonia severity, we conducted a prospective survey. SUBJECTS AND METHODS: The survey was conducted from July 2006 to March 2007 as a nationwide joint study by 200 institutions. The study subjects included patients aged ≥16 years of age who had CAP. The severity at initial consultation was determined using the criteria established by JRS 2005, JRS 2000, and Infectious Diseases Society of America Guidelines (IDSA-GLs). The survival outcome 30 days after the start of the initial antimicrobial agent treatment was confirmed. RESULTS: A total of 1875 patients were analyzed. The numbers of cases of pneumonia assessed as being moderate and severe were significantly lower when the JRS 2005 criteria were used than when the JRS 2000 criteria were used. Thus, the severity of pneumonia could be determined more appropriately using the JRS 2005 criteria. Furthermore, the severity-dependent prediction of fatal outcomes or mortality according to these criteria was similar to that determined using the IDSA-GLs. CONCLUSIONS: Determining severity on the basis of JRS 2005 can resolve nearly all the problems encountered with JRS 2000; these criteria were found to be useful and rapidly and easily applicable in clinical practice.

Nationwide survey on the 2005 Guidelines for the Management of Community-Acquired Adult Pneumonia: validation of differentiation between bacterial pneumonia and atypical pneumonia.

INTRODUCTION: The Japanese Respiratory Society Guidelines for the Management of Community-Acquired Pneumonia (CAP) in Adults (JRS 2005) was published as a revision of the Basic Concept for the Management of CAP in Adults (JRS 2000). To evaluate the JRS 2005 criteria for differentiating between disease types and assessing the status of antimicrobial agent use in initial treatment, we conducted a prospective survey. SUBJECTS AND METHODS: The survey was conducted from July 2006 to March 2007 as a nationwide joint study by 200 institutions. The study subjects included patients aged ≥16 years of age who had CAP, and patients who met the inclusion criteria were consecutively enrolled. Disease type differentiation based on JRS 2005 and JRS 2000 was conducted. Disease type diagnosis was also performed based on test results. The sensitivity and specificity of disease type differentiation were calculated. The antimicrobial agents used in the initial treatment were classified as recommended or non-recommended based on JRS 2005. The validity of non-recommended antimicrobial agent use was investigated. RESULTS: A total of 1875 patients were analyzed. Differentiation of atypical pneumonia using the JRS 2005 criteria had higher sensitivity and lower specificity than differentiation using the JRS 2000 criteria. The antimicrobial agents recommended by JRS 2005 were used as initial treatment in a low number of cases. The efficacy of the recommended antimicrobial agents was similar to that of the non-recommended agents. CONCLUSIONS: JRS 2005 is advantageous in terms of reducing the number of items used in disease type differentiation. The recommended antimicrobial agents used for the initial treatment are believed to be appropriate.

Efficacy and safety of moxifloxacin for community-acquired bacterial pneumonia based on pharmacokinetic analysis.

Moxifloxacin is a respiratory quinolone that is expected to be useful for treating community-acquired bacterial pneumonia, but few clinical studies and not a detailed evaluation of its pharmacokinetics have been conducted in Japan in patients with pneumonia. We assessed the efficacy and safety of moxifloxacin in 18 patients with community-acquired bacterial pneumonia using pharmacokinetic-pharmacodynamic analysis. There was significant improvement in body temperature, white blood cell count, C-reactive protein, and chest X-ray score on day 3 of moxifloxacin treatment, which persisted until the completion of treatment (all p < 0.05). Nine strains, including Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, and Enterobacter cloacae, were isolated from sputum cultures of nine patients. The isolated strains were eradicated by moxifloxacin. The mean area under the concentration-time curve from 0 to 24 hours [AUC(0-24 h) (AUC(0-24 h,ss))], maximum plasma concentration (C(max)), and trough plasma level (C(trough)) of moxifloxacin at steady state was 52.0 µg h/ml, 4.5, and 0.9 µg/ml, respectively. Mean AUC(0-24 h,ss)/mimimum inhibitory concentration (MIC), and C(max)/MIC ratios for patients in whom MICs of moxifloxacin were determined for pathogenic bacteria were 723 and 62, respectively. The median AUC(0-24 h,ss)/MIC and C(max)/MIC ratios (based on Monte Carlo simulation employing MICs for 257 strains of S. pneumoniae collected during a respiratory infection survey by the Japanese Society of Chemotherapy in 2007) were 209.56 and 17.88, respectively. Thus, when the target for the AUC/MIC ratio was set at ≥30 and that for the C(max)/MIC ratio at ≥5, the achievement rate for these two parameters was 97.36% and 96.71%, respectively. Two patients (11%) experienced three adverse effects [one nausea, another increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], but the events were not serious. Based on these results, moxifloxacin (400 mg once daily) was considered useful for treating community-acquired bacterial pneumonia and is expected to show excellent efficacy and safety as well as suppressing the emergence of resistance.

QuantiFERON TB-2G test for patients with active tuberculosis stratified by age groups.

We evaluated the usefulness of the QuantiFERON TB-2G (QFT-2G) test and the tuberculin skin test (TST) in patients with active tuberculosis (TB) disease stratified by age in 10-year increments. Although the positive rate on TST was over 80% in younger patients aged < or =9 years, it decreased to 55% in patients of aged 70-79 years and 33% in patients aged over 80 years. However, the positive rate on QFT-2G test was over 80% for the age groups between 10-19 and 60-69 years, excluding younger patients aged < or =9 years. Furthermore, the rate was 79% in patients aged 70-79 years and 75% in patients over 80 years of age. The positive response rate of the QFT-2G test was significantly higher than that of the TST in patients over 50 years of age. The indeterminate result of the QFT-2G test increased with age and it is suggested that this result is concerned with the severity of underlying diseases in patients with active TB disease. Although the positive rate on QFT-2G test decreased with age in adults, it is thought to be a useful supportive diagnostic method for active TB disease compared to the TST, except in younger patients aged < or =9 years old.

Evaluation of clinical dosage of gatifloxacin for respiratory tract infections in elderly patients based on pharmacokinetics/pharmacodynamics (PK/PD).

The efficacy and safety of gatifloxacin (GFLX) was evaluated for elderly patients with respiratory infections. Each patient received one-half (100 mg b.i.d.) or one-quarter (100 mg q.d.) of the conventional dosage of 200 mg b.i.d., after a tentative clinical dosage for GFLX was estimated based on the patient's age and body weight. The subjects were 34 patients aged 65 years or older with mild to moderate acute bronchitis, pneumonia, or chronic respiratory tract infections. The serum concentration of GFLX was measured for each patient, and population and pharmacokinetic (PPK) analysis was performed, using the Bayesian method, to calculate the AUC and maximum drug concentration (Cmax). The overall efficacy rate of GFLX for 33 patients was 87.9% (29/33 patients). GFLX was effective for 75.0% (6/8 patients) in the 100-mg dosage group and 92.0% (23/25 patients) in the 200-mg dosage group. The clinical efficacy was 90.0% (9/10 patients) for acute bronchitis, 86.7% (13/15 patients) for pneumonia, and 87.5% (7/8 patients) for chronic respiratory tract infections. The bacterial eradication rate was 85.7% (12/14 patients). No adverse events or laboratory abnormalities were observed. The AUC values were 11.2-37.5 microg.h/ml and 12.7-111 microg.h/ml for the 100-mg and 200-mg dosage groups, respectively, and the Cmax values were 1.28-3.02 microg/ml and 0.72-6.35 microg/ml, respectively, for the two groups. These results suggest that the dosage of GFLX examined in this study is clinically useful in elderly patients aged 65 or older with acute bronchitis, pneumonia, or chronic respiratory tract infections. The results of PPK analysis with the dosage management also support the efficacy of GFLX.

Clinical evaluation for diagnosing active TB disease and transitional change of two commercial blood tests.

We compared the usefulness of TST, QFT-TB and T-SPOT.TB for the identification of patients with active tuberculosis (TB) disease and investigated transitional change in both tests during anti-tuberculous treatment. The subjects were 50 healthy volunteers and 48 patients with active TB disease between October 2005 and December 2006. Among active TB disease patients, 60% had a positive TST result, 81% had a positive QFT-TB result, and 87% had a positive T-SPOT.TB result. Indeterminate results of QFT-TB and T-SPOT.TB were recognized in 12% and 6% of patients, respectively. Negative results on QFT-TB and T-SPOT.TB were 6% each. QFT-TB had a sensitivity of 81% for active TB disease. T-SPOT.TB had a sensitivity of 88% for active TB disease. With regard to transitional changes in QFT-TB results and T-SPOT.TB results, both test results showed a positive response in over 40% of patients 12 months after anti-tuberculous treatment. In conclusion, both blood assays seemed to be more useful than TST for the identification of patients with active TB disease. However, neither of the 2 blood tests appears to provide any certainty regarding the cure of infection.

Multicenter survey on hospital-acquired pneumonia and the clinical efficacy of first-line antibiotics in Japan.

OBJECTIVE: The aim of this study was to investigate the pathophysiology of hospital-acquired pneumonia (HAP) and the clinical efficacy of its first-line treatment and to examine the validity of "the Japanese Respiratory Society (JRS) Guidelines for management of HAP". METHODOLOGY: The observational survey was conducted during the period of June 2002-May 2004 and patients with HAP were prospectively surveyed using the consecutive enrollment method. A total of 1,356 patients from 254 hospitals nationwide were analyzed. Clinical response to first-line antibiotics was evaluated at the end of the medication. RESULTS: The 30-day mortality rate was 19.8%. Patients were classified into four groups according to the JRS guideline criteria. There were remarkable variances in the number of cases of each group. Mild/moderate pneumonia with no risk factors (group I) accounted for 0.3% of all cases. The mortality rate tended to be higher, as clinical conditions became more serious (group II < III < IV). Alternatively, though categorized in the same group (group III), there was a difference in the mortality rate by the severity of pneumonia (severe cases 32.2% vs. moderate cases 11.0%). First-line medication using carbapenems accounted for 61.7% of total cases. The efficacy rate of guideline-concordant therapy was significantly higher than that of guideline-discordant therapy (54.2% vs. 41.7%). CONCLUSIONS: This is the first nationwide study on HAP in Japan. The clinical characteristics and prognosis of HAP were elucidated. Review of the current classification of the disease is required and these results provide valuable information for the next revision of the guidelines.

Clinical utility of the QuantiFERON TB-2G test for elderly patients with active tuberculosis.

OBJECTIVE: To evaluate the response to the QuantiFERON-TB-2 Gold (QFT-2G) test (Cellestis Ltd; Carnegie, VIC, Australia) in elderly patients with active tuberculosis (TB) to determine whether the QFT-2G test might be a feasible method for diagnosing TB infection in this group of patients. METHODS: The subjects were 30 elderly patients with active TB and 100 younger patients with active TB. The QFT-2G test results were analyzed in relation to combined and separate responses to early secretory antigenic target 6-kD (ESAT-6) protein and culture filtrate protein 10 (CFP-10) antigens. RESULTS: Of the 30 elderly patients with active TB, 27% had a positive tuberculin skin test (TST) result and 77% had a positive QFT-2G test result. Of the 100 younger patients with active TB, 70% had a positive TST result and 87% had a positive QFT-2G test result. Although there was no significant difference between the two patient groups in the positive rate for the QFT-2G test results (p = 0.185), there was a significant difference in the rates of positive TST results between the elderly and younger patients (p = 0.012). The positive test result rate for both ESAT-6 and CFP-10 antigens in the elderly patients (17%) was significantly lower than that in younger patients (37%; p = 0.038). There was an indeterminate result for the QFT-2G test in five elderly patients, and this might have been related to the presence of lymphocytopenia due to underlying disease. A negative result on the QFT-2G test was detected in two elderly patients, and this might have been related to the severity of the active TB. CONCLUSION: We confirmed that the QFT-2G test might be a more useful method of diagnosing TB infection than the TST for elderly patients if peripheral lymphocyte counts have been preserved.

Clinical features of immunocompromised and nonimmunocompromised patients with pulmonary tuberculosis.

Although patients with risk factors for tuberculosis have increased with the increased use of immunosuppressive therapy, there have been few reports about differences in clinical findings between immunocompromised patients and nonimmunocompromised patients with pulmonary tuberculosis. Therefore, we investigated differences between the clinical features of immunocompromised patients with pulmonary tuberculosis and those of nonimmunocompromised patients in the past decade. We analyzed findings in 840 patients (312 immunocompromised and 528 nonimmunocompromised) with pulmonary tuberculosis who were found to be culture-positive for Mycobacterium tuberculosis between January 1997 and December 2006. The characteristic clinical findings of the immunocompromised patients, compared with findings in the nonimmunocompromised group, were as follows: (1) an increase in the number of patients with respiratory symptoms during the period of follow-up of underlying diseases; (2) an increase in the number of patients in a hyponutritional state and with a negative response for the tuberculin skin test; (3) an increase in the number of microbiologically smear-positive sputum specimens; (4) an increase in the number of patients with atypical radiological findings, such as a few cavities or calcification, bilateral and expansive consolidation, miliary shadows, and mediastinal and/or hilar lymphadenopathy ; (5) an increase in the number of patients with misdiagnosed pneumonia at admission; and (6) an increase in the mortality rate. We concluded that, among the immunocompromised patients with pulmonary tuberculosis, there were many patients with atypical radiological findings and with smear-positive findings for acid-fast bacilli examination that was carried out to isolate M. tuberculosis (which had become infectious). We must perform the acid-fast bacilli examination for patients who have a fever and continuous cough, and antituberculous drugs should be administered as soon as possible when the results are positive.

Study of nasopharyngeal bacterial flora. Variations in nasopharyngeal bacterial flora in schoolchildren and adults when administered antimicrobial agents.

Changes in nasopharyngeal bacterial flora in adults with acute upper respiratory tract infection on administration of antimicrobial agents were investigated, and how these changes contrasted with those in children. Many patients with acute sinusitis due to allergies, and patients with malignancy and diabetes mellitus were included in the investigation. The detection rates of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, the major bacteria of acute otitis media (AOM), were 22%, 10%, and 7% respectively, which were significantly lower than those for children. Gram stain examination of nasopharyngeal swab samples showed a significant relation between leukocyte infiltration and the detection amount of S. pneumoniae (P = 0.0086). A significant relation (P = 0.0134) was also observed when H. influenzae was simultaneously detected. No significant change in the three major AOM bacteria present in nasopharyngeal bacterial flora after administration of antimicrobial agents was observed. However, all S. pneumoniae and H. influenzae detected after antimicrobial agent administration had the beta-lactam-resistance gene. It was observed that a significant improvement in leukocyte infiltration occurred 6 to 10 days after antimicrobial agent administration. In contrast, a significant improvement in children was observed at 2 to 5 days. In the adult subjects, this improvement was probably due to spontaneous remission rather than the effect of the antimicrobial agents. Although investigation of the long-term administration of antimicrobial agents was also conducted, its benefits for the patients were not elucidated.

The microbiological and clinical effects of combined therapy according to guidelines on the treatment of pulmonary Mycobacterium avium complex disease in Japan - including a follow-up study.

BACKGROUND: The difficulty of treatment for pulmonary Mycobacterium avium complex (MAC) in Japan. OBJECTIVES: To investigate the clinical and microbiological effects of treatment according to the guidelines proposed by the American Thoracic Society and the Japanese Society for Tuberculosis and prospective follow-up studies after the completion of treatment of patients with pulmonary MAC disease. METHODS: Analysis of the microbiological effects with regard to sputum conversion rate and the sputum relapsing rate and the clinical effects with regard to clinical symptoms and radiological findings for patients with pulmonary MAC disease treated with a regimen consisting of rifampicin, ethambutol, streptomycin, and clarithromycin over 24 months and follow-up over 12 months. RESULTS: Sixty-five patients with pulmonary MAC disease were enrolled in this trial. In 39 patients, negative sputum conversion was observed within 6 months after the initiation of this regimen, 16 relapsed, and 20 experienced clinical worsening within 1 year after the completion of treatment. Although retreatment with the same regimen or a regimen including new quinolones was carried out for these patients, we could not achieve negative sputum conversion and/or clinical improvement. CONCLUSIONS: We believe that the dose of clarithromycin for pulmonary MAC disease may be increased and recommend surgery for patients with a localized lesion at early-stage MAC disease to prevent a high rate of relapse.

A double-blind randomized study of aminoglycoside infusion with combined therapy for pulmonary Mycobacterium avium complex disease.

A prospective study of the clinical efficacy of an aminoglycoside antibiotic (streptomycin, SM) for the treatment of pulmonary Mycobacterium avium complex (MAC) disease was carried out. In a multicenter trial, patients with pulmonary MAC disease received protocol-guided combined chemotherapy with or without SM. SM was given to the patients intramuscularly 15 mg/kg three times per week for the initial 3 months and three other antibiotics (rifampicin, ethambutol, and clarithromycin) were added and administered for over 24 months after the conversion of MAC strains. From April 1998 to December 2004, 160 HIV-negative patients were enrolled in this trial. Fourteen patients were found to be ineligible because they could not continue the treatment, and they were excluded from the analysis after randomization. Seventy-three patients were assigned to receive combined chemotherapy with SM (group A) and 73 were assigned to receive combined chemotherapy without SM (group B). The median durations of treatment were 27.6 months in group A and 28.4 months in group B. The difference in the backgrounds of the groups was not statistically significant. There were no differences in microbiological and radiological findings between the groups, but the sputum conversion rate for pulmonary MAC disease at the completion of treatment was significantly higher in group A than that in group B. Although, there were no significant differences in the sputum relapse rate and clinical improvement including both clinical symptoms and radiological findings, group A showed better initial microbiological response than group B. As for adverse reactions and abnormal laboratory findings, there were no significant differences between the groups. Based on the results of this double-blind randomized study, we support treatment including SM according to both the American Thoracic Society (ATS) and the Japanese Society for Tuberculosis (JST) guidelines for patients with pulmonary MAC disease without HIV infection.

Evaluating the use of a Streptococcus pneumoniae urinary antigen detection kit for the management of community-acquired pneumonia in Japan.

BACKGROUND: The urinary antigen detection kit for Streptococcus pneumoniae was tested. OBJECTIVES: It was our aim to evaluate the usefulness of the immunochromatographic membrane test by doing a large prospective study of community-acquired pneumonia (CAP) in Japan. METHODS: We prospectively evaluated the use of the S. pneumoniae urinary antigen detection kit and analyzed the treatment and clinical effect seen in patients with positive test kit results. One hundred and fifty-six patients with CAP admitted to our hospital between October 2001 and September 2003 were evaluated. RESULTS: In 49% of these CAP patients, the causative microorganisms were isolated. S. pneumoniae was suspected to be the causative microorganism in 15%, but positive results of the urinary antigen detection kit indicated S. pneumoniae to be a probable microorganism in 28%, even though antibiotics had previously been administered to half of the patients. The kit was particularly useful for diagnosing patients with poor quality sputum in whom antibiotics treatment nevertheless had to be selected. Antibiotics appropriate for S. pneumoniae (mainly penicillin) were given. The treatment was found to have excellent clinical results in 89% of the CAP patients. CONCLUSIONS: The S. pneumoniae urinary antigen detection kit was considered to be useful in selecting treatment since there was a high level of clinical effectiveness when the most suitable antibiotics were immediately administered to positive patients. The use of the S. pneumoniae urinary antigen kit is rapid and simple compared with conventional microbiological procedures.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2004)].

From October 2004 to September 2005, we collected the specimen from 319 patients with lower respiratory tract infections in 12 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and patients' characteristics. Of 383 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 381 strains were examined. The breakdown of the isolated bacteria were: Staphylococcus aureus 87, Streptococcus pneumoniae 80, Haemophilus influenzae 78, Pseudomonas aeruginosa (non-mucoid) 35, P. aeruginosa (mucoid) 9, Klebsiella pneumoniae 15, Moraxella subgenus Branhamella catarrhalis 30, etc. Of 87 S. aureus strains, those with 2 microg/mL or less of MIC of oxacillin (methicillin-sensitive S. aureus: MSSA) and those with 4 microg/mL or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) were 40 (46.0%) and 47 (54.0%) strains, respectively. Against MSSA, imipenem had the most potent antibacterial activity and inhibited the growth of all the strains at 0.063 microg/mL. Against MRSA, vancomycin showed the most potent activity and inhibited the growth of all the strains at 1 microg/mL. Arbekacin (ABK) also showed the potent activity and its MIC90 was 2 microg/mL. Carbapenems showed the most potent activities against S. pneumoniae and inhibited the growth of all the strains at 0.25-0.5 microg/mL. Cefozopran (CZOP) also had a preferable activity (MIC90: 1 microg/mL) and inhibited the growth of all the strains at 2 microg/mL. In contrast, there were high-resistant strains (MIC: 128 microg/mL or more) for ABK (2.5%), erythromycin (37.5%), and clindamycin (38.8%). Against H. influenzae, levofloxacin showed the most potent activity and inhibited the growth of all the strains at 0.125 microg/mL. Meropenem showed the most potent activity against P. aeruginosa (mucoid) and inhibited the growth of all the strains at 2 microg/mL. Against P. aeruginosa (non-mucoid), amikacin (AMK) had the most potent activity and its MIC90 was 4 microg/mL. The activity of CZOP against the non-mucoid type also was preferable and its MIC90 was 8 microg/mL. Against K. pneumoniae, CZOP, cefmenoxime, cefpirome, flomoxef were the most potent activity and inhibited the growth of all the strains at 0.063 microg/mL. Also, all the agents generally showed a potent activity against M. (B.) catarrhalis and the MIC90 of them were 4 microg/mL or less. The approximately half the number (57.0%) of the patients with respiratory infection were aged 70 years or older. Bacterial pneumonia and chronic bronchitis accounted for 50.8% and 23.8% of all the respiratory infection, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (21.6%), S. pneumoniae (24.7%) and H. influenzae (20.1%). S. aureus (20.9%), S. pneumoniae (16.1%), and H. influenzae (16.1%) also were relatively frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from the patients were S. pneumoniae (22.3%) and H. influenzae (25.1%). The bacteria relatively frequently isolated from the patients treated with macrolides were P. aeruginosa and the isolation frequency was 43.5%.

Study of nasopharyngeal bacterial flora. Second report. Variations in nasopharyngeal bacterial flora in children aged 6 years or younger when administered antimicrobial agents. Part 1.

In our first report, we investigated nasopharyngeal bacterial flora related to penicillin-resistant Streptococcus pneumoniae (PRSP) and beta-lactamase-negative ampicillin-resistant Haemophilus influenzae (BLNAR) and their relation to acute upper respiratory tract infection (AURTI). This report analyzes the results of a study of nasopharyngeal bacterial flora before the administration of antimicrobial agents in 172 AURTI patients aged 6 years or younger. In addition to Gram staining, microscopic observation, and culturing, a polymerase chain reaction (PCR) method was used to identify PRSP (gPRSP) and BLNAR (gBLNAR) drug-resistant genes. Of the patients analyzed, 90% had acute otitis media (AOM) and were aged 2 years or younger. The antimicrobial agents administered were amoxicillin (34%), clavulanic acid/amoxicillin (11%), cefditren pivoxil (CDTR-PI) (43%), and others (12%). This was particularly true for patients administered CDTR-PI, among whom there were many who had already suffered one or more episodes of AOM by the age of 1 year or younger, and many in which gPRSP were detected (P < 0.01). There was a significant relation between the degree of nasopharyngeal inflammation indicated by leukocyte infiltration images and the amount of S. pneumoniae and H. influenzae detected, which are the main pathogenic bacteria causing AOM (P < 0.01). In addition to leukocyte infiltration images, there were cases in which shedding of ciliated cells was observed and/or giant monocytic cells. Both nasopharyngeal leukocyte infiltration images and/or shed cell findings observed in infant AURTI cases are important indices for the prompt detection of gPRSP and/or gBLNAR and appropriate doses of antimicrobial agents.

Study of nasopharyngeal bacterial flora. Second report. Variations in nasopharyngeal bacterial flora in children aged 6 years or younger when administered antimicrobial agents. Part 2.

This report focuses on changes in the nasopharyngeal bacterial flora before and after administration of antimicrobial agents in 172 cases of acute upper respiratory infection in patients aged 6 years or younger. The antimicrobial agents administered were amoxicillin (AMPC) (34%), clavulanic acid/amoxicillin compound (11%), cefditren pivoxil (CDTR-PI) (43%), and others (12%). Changes in nasopharyngeal bacterial flora were investigated with reexaminations conducted after 2-5 days (day 2-5 subgroup), 6-10 days (day 6-10 subgroup), and 11 days and thereafter. There was a significant reduction in the Streptococcus pneumoniae detected in the group administered AMPC (AMPC group) in the day 2-5 subgroup and the day 6-10 subgroup. There was also a significant decrease in H. influenzae in the group administered CDTR-PI (CDTR-PI group) in the day 2-5 subgroup. From this it was inferred that for the most part significant changes in infectious nasopharyngeal bacteria occurred in the day 2-5 subgroups. However, a significant improvement in the degree of inflammation, as indicated by leukocyte infiltration images for the AMPC group, was observed in the day 2-5 subgroup, and for the CDTR-PI group in the day 6-10 subgroup. On the other hand, in both the antimicrobial agent groups, S. pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis were newly detected at reexamination. Furthermore, a difference in the incidence of these bacteria was observed between the 2 antimicrobial agent groups. It was suggested that such phenomena related to the survival of resistant strains or a recurrence otitis media.

Drug-resistant genes and serotypes of pneumococcal strains of community-acquired pneumonia among adults in Japan.

BACKGROUND: A high frequency of drug-resistant pneumococci has been reported in Asian countries. Few data on the drug-resistance or serotype of pneumococcal strains responsible for community-acquired pneumonia (CAP), however, are available for the past two decades in Japan. METHODOLOGY: Susceptibility to antibiotics and the genotype of antibiotic-resistant genes and serotypes of Streptococcus pneumoniae isolates from 114 adult patients with CAP were examined in a nationwide study in Japan between 2001 and 2003. RESULTS: Most of the cases were non-bacteraemic pneumonia and the case fatality rate was 4.4%. The most frequent genotype of the pbp gene was pbp1a + 2x + 2b (gPRSP; 36.8%) followed by pbp 2x (28.1%) and of the macrolide-resistant gene, it was ermB (50.0%). The most common serotype was 19F (29.1%), followed by serotype 23F (13.2%), 6B (12.3%) and 3 (11.4%). The coverage of serotypes of isolates by a 23-valent pneumococcal polysaccharide vaccine (PPV) would be 82.5% in these patients with CAP. Most of strains with serotypes 19F and 23F were gPRSP. A cluster of serotype 3 strains associated with the pbp 2x and ermB gene was also noted. CONCLUSION: A high frequency of altered pbp gene mutations or of macrolide-related genes and a high serotype coverage by the 23-valent PPV found in our study of pneumococcal pneumonia facilitates attempts to increase the coverage rate of the 23-valent PPV in adults older than 65 years in Japan.