PROTEKT 1999–2000: a multicentre study of the antimicrobial susceptibility of respiratory tract pathogens in Japan

AMPICILLIN SULBACTAM AND CEFOTAXIME ARE SIMILARLY EFFECTIVE IN PEDIATRIC PNEUMONIA

Pneumonia is an infection of the lungs that occurs and still cause high mortality in young children today. The main cause is bacterial or viral. Antibiotics still recommended though it is difficult to know the cause is bacterial or viral. Ampicillin be the first option some guideline. Increased resistance worldwide become one of them concerns the effectiveness of antibiotics. The main treatment of toddler pneumonia in Muhammadiyah Hospital Lamongan are ampicillin sulbactam and cefotaxime. The study was conducted to analyze the effectiveness of both antibiotics. This study aims to analyze comparison in the use of ampicillin sulbactam and cefotaxime pneumonia patients aged 3-59 months from November 2013 to March 2014. Patients who met the inclusion criteria were prospectively observed for clinical data, laboratory data, the data microbiology. After it is analyzed to know the difference between the effectiveness of antibiotics. In this study of 29 patients included in the inclusion criteria, 17 patients who received antibiotics ampicillin sulbactam and 12 patients receiving cefotaxime. In the comparison of the mean pulse pulse is known there is a significant reduction in both groups of patients on the second day and was not significantly different between the two groups (p = 0.084). Likewise, the average ratio of temperature (p = 0.117), breath rate (p = 0.839), leukocytes of patients (p = 0.429). Length of stay for ampicillin sulbactam group was 4.77 days and 5.17 days for cefotaxime group. Analysis showed no differences between the two groups for lenght (p = 0.275). Of the 22 patients who were sampled for blood culture examination only 1 patient with positive results. Based on these results we can conclude that ampicillin sulbactam and cefotaxime effective in cases of children pneumonia, and there is no distinction based on the parameters in body temperature, breath rate, pulse, leukocytes and long hospitalization of patients. Regimentation dosage is appropriate based on guidelines, and length of stay less than 10 days. Found no side effects of both drugs.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Antimicrobial activities of piperacillin-tazobactam against Haemophilus influenzae isolates, including beta-lactamase-negative ampicillin-resistant and beta-lactamase-positive amoxicillin-clavulanate-resistant isolates, and mutations in their quinolone resistance-determining regions

Beta-lactamase-negative ampicillin-resistant (BLNAR) isolates of Haemophilus influenzae have been emerging in some countries, including Japan. The Clinical and Laboratory Standards Institute has only a susceptible MIC breakpoint (< or = 1 microg/ml) for piperacillin-tazobactam and a disclaimer comment that BLNAR H. influenzae should be considered resistant, which was adapted without presentation of data. In addition, fluoroquinolone-resistant H. influenzae isolates have recently been occasionally reported worldwide. To address these problems, we examined susceptibilities to beta-lactams, including piperacillin-tazobactam, and ciprofloxacin by microdilution and disk diffusion (only for piperacillin-tazobactam) methods, against a total of 400 recent H. influenzae clinical isolates, including 100 beta-lactamase-negative ampicillin-susceptible, beta-lactamase-positive ampicillin-resistant, BLNAR, and beta-lactamase-positive amoxicillin-clavulanate-resistant (BLPACR) isolates each. BLNAR and BLPACR isolates were tested by PCR using primers that amplify specific regions of the ftsI gene. We also detected mutations in quinolone resistance-determining regions (QRDRs) by direct sequencing of the PCR products of DNA fragments. Among beta-lactams, piperacillin-tazobactam exhibited potent activity against all isolates of H. influenzae, with all MICs at < or = 0.5 microg/ml (susceptible). A disk diffusion breakpoint for piperacillin-tazobactam of > or = 21 mm is proposed. We confirmed that all BLNAR and BLPACR isolates had amino acid substitutions in the ftsI gene and that the major pattern was group III-like (87.5%). One ciprofloxacin-resistant isolate (MIC, 16 microg/ml) and 31 ciprofloxacin-susceptible isolates (MICs, 0.06 to 0.5 microg/ml) had amino acid changes in their QRDRs. Piperacillin-tazobactam was the most potent beta-lactam tested against all classes of H. influenzae isolates. It is possible that fluoroquinolone-resistant H. influenzae will emerge since several clinical isolates carried mutations in their QRDRs.

Antimicrobial susceptibility of respiratory tract pathogens in Japan during PROTEKT years 1-5 (1999-2004)

Susceptibility to a range of antimicrobial agents was determined among isolates of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae collected in 12 centers throughout Japan during years 1-5 (the respiratory seasons of 1999-2004) of the longitudinal Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin study. The most frequent source of isolates of S. pneumoniae was from patients with community-acquired pneumonia (CAP) (25.3%). Reduced susceptibility to penicillin or erythromycin resistance was common among S. pneumoniae isolates (30.9-44.5% and 77.2-81.9%, respectively). The macrolide MIC(50) for S. pneumoniae was >or=128 microg/ml (azithromycin and erythromycin) and >or=64 microg/ml (clarithromycin). The erm(B) genotype accounted for the most erythromycin-resistant isolates in each study year. H. influenzae isolates were most commonly derived from patients with CAP (26.2%). The proportion of H. influenzae isolates that were beta-lactamase positive ranged between 4.3% and 9.7%. The prevalence of beta-lactamase-negative ampicillin-resistant isolates increased from 0.4% to 2.6% between years 1 and 4 then to 19.7% in year 5. S. pyogenes isolates were highly susceptible to most antimicrobial agents except macrolides and tetracycline. Telithromycin was highly active against all three pathogens examined throughout the study.

Antibiotic susceptibility of Haemophilus influenzae strains isolated from various clinical sources in Hokkaido Prefecture, Japan

Any increase in beta-lactam-resistant Haemophilus influenzae is a serious problem in respiratory and otolaryngology medicine. In this study, we examined the antibiotic susceptibility and genotype of 457 clinical Haemophilus influenzae strains isolated in Hokkaido Prefecture, Japan. Strains with beta-lactam-resistant mutations in gene encoding penicillin-binding protein 3 were more frequently found in lower respiratory tract specimens (sputa) than in upper respiratory tract specimens, such as rhinorrhea. The existence of the TEM-1 beta-lactamase gene occurred more frequently in adult patients than in pediatric patients. The results suggest that beta-lactam-resistant or nonsusceptible strains are more prevalent in adult patients with respiratory diseases. We observed only a very few strains which were nonsuscpetible to third-generation cephalosporins (CEPs) and carbapenems. However, 12%-13% of the strains were shown to be resistant to penicillins and second-generation CEPs, and approximately 4% of the strains were shown to be nonsusceptible to fourth-generation CEPs. In addition, we identified tetracycline-resistant (2.8%), chloramphenicol-resistant (0.6%), clarithromycin-resistant (2.6%), and fluoroquinolone-nonsusceptible (approximately 2%) H. influenzae strains.

Emergence of fluoroquinolone-resistant Haemophilus influenzae strains among elderly patients but not among children

We screened 457 Haemophilus influenzae strains isolated in Japan during 2002 to 2004 and identified 12 fluoroquinolone-resistant strains (2.6%). The resistant strains were divided into three genotypes (eight, three, and one of each type). These were isolated from patients over 58 years of age. Several fluoroquinolone-resistant clones appeared to have invaded the population of elderly patients in a particular area, Sapporo city.

Resistance of Haemophilus influenzae isolates in children under 5 years old with acute respiratory infections in China between 2000 and 2002

This prospective, three-centre study tested for antimicrobial susceptibility in 898 isolates of Haemophilus influenzae between 2000 and 2002 in Chinese children aged under 5 years with acute upper respiratory tract infection. The average incidence of beta-lactamase production was 12.0%. Overall, 88.0% of isolates were susceptible to ampicillin, 100.0% were susceptible to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime and azithromycin, and 99.0% were susceptible to ciprofloxacin. Isolates from Beijing and Shanghai had a lower susceptibility to tetracycline (57.0% and 61.0%, respectively) compared with those from Guangzhou (81.0%), while trimethoprim/sulfamethoxazole susceptibilities in Shanghai (47.0%) and Guangzhou (54.0%) were significantly higher than in Beijing (35.0%). A total of 34.5% of all the isolates were susceptible to all eight of these antimicrobial agents and 12.8% were multi-drug resistant. Ampicillin resistance increased over the duration of the study. These findings show that beta-lactamase production and ampicillin resistance among isolates from Chinese children with upper respiratory tract infection are increasing, and highlight the strong correlation between ampicillin resistance and resistance to cefaclor, chloramphenicol and tetracycline in H. influenzae isolates.

High prevalence of erythromycin resistance and macrolide-resistance genes, mefA and ermB, in Streptococcus pneumoniae isolates from the upper respiratory tracts of children in the Sapporo district, Japan

Our previous study demonstrated that the frequency of penicillin-resistant Streptococcus pneumoniae (PRSP) was lower in our district than in districts in other Japanese studies. In this study, we investigated the prevalence of erythromycin resistance. The susceptibility to erythromycin and the distribution of the macrolide-resistance genes, mefA and ermB, were examined in S. pneumoniae isolates from the upper respiratory tracts of children in four cities in the Sapporo district, Hokkaido prefecture, Japan. Of the 156 isolates, 27 (17.3%) were erythromycin-sensitive, 6 (3.9%) were erythromycin-intermediately resistant, and 123 (78.9%) were erythromycin-resistant. Fifty-nine (37.8%) had the mefA gene, 89 (57.1%) had the ermB gene, and 129 (82.7%) had the mefA and/or the ermB gene. The ermB-positive isolates tended to show high resistance to erythromycin. Erythromycin-resistant isolates and the macrolide-resistance genes were often present in infants or younger children. The frequency of erythromycin-resistant isolates in the four cities was very high, ranging from 76.3% to 83. 3%, as high as the national average. Although erythromycin-resistant isolates generally tend to show cross-resistance to penicillin, the frequency of PRSP was very low in this study, as compared with other Japanese studies. Erythromycin resistance was frequently recognized not only in PRSP but also in penicillin-sensitive S. pneumoniae (PSSP) as well. In Japan, erythromycin resistance may have already become widespread, even in local areas where penicillin resistance is not especially prevalent.

Therapeutic options for pneumococcal pneumonia in Turkey

BACKGROUND

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide. Streptococcus pneumoniae continues to be the most important causative agent in CAP.

OBJECTIVE

This article reviews options for the empiric treatment of pneumococcal pneumonia in Turkey based on local epidemiologic data.

METHODS

This was a retrospective review of studies evaluating antimicrobial susceptibility patterns among clinical isolates of S pneumoniae in Turkey from 2000 onward. Relevant studies were identified through literature searches of both Turkish (Ulakbim and Pleksus) and international (MEDLINE) databases using the search terms S pneumoniae and Turkey. Only antibiotics likely to be used in pneumococcal pneumonia were evaluated. The minimum concentration required to inhibit 90% of isolates (MIC(90)) for each antibiotic was obtained by averaging all reported values to arrive at a single value for the entire country.

RESULTS

The MIC(90) for penicillin was 1 g/mL; among all isolates of S pneumoniae, 6.4% were penicillin resistant and 30.9% showed intermediate susceptibility. The MIC(90)s and overall rates of resistance (combined intermediate susceptibility and resistance) for the other antibiotics studied were as follows: cefaclor, 4 microg/mL (26.3%); cefuroxime, 2 microg/mL (15.4%); ceftriaxone, 0.25 microg/mL (0.75%); imipenem, 0.06 microg/mL (0%); erythromycin, 2 microg/mL (13.9%); clarithromycin, 2 microg/mL (13.7%); azithromycin, 2 microg/mL (13.8%); telithromycin, 0.06 microg/mL (no published breakpoints); trimethoprim-sulfamethoxazole, 4 microg/mL (63.8%); tetracycline, 16 microg/mL (24.6%); ciprofloxacin, 2 microg/mL (no published breakpoints); ofloxacin, 2 microg/mL (4%); levofloxacin, 1 microg/mL (0%); gemifloxacin, 0.06 microg/mL (no published breakpoints); and moxifloxacin, 0.06 microg/mL (0%). Penicillin G, at standard parenteral doses, has been shown to achieve concentrations above the MIC for >40% to 100% of the dosing interval, depending on the MIC of the isolate. Based on pharmacodynamic studies, the MIC(90) for penicillin in Turkey should easily be exceeded with the use of penicillin G 3 mU QID. In vitro, susceptibility is generally greater to amoxicillin than to penicillin, with average amoxicillin MIC values approximately 1 dilution lower than those for penicillin. Amoxicillin's better pharmacodynamic/pharmacokinetic properties relative to penicillin make it a reasonable option for the treatment of CAP. In pharmacodynamic studies, amoxicillin 1 g TID achieved and maintained serum concentrations of 2 to 4 microg/mL for at least 40% of the dosing interval. A new formulation of amoxicillin/clavulanate given 2000/125 mg BID is expected to eradicate isolates of S pneumoniae at an amoxicillin MIC < or = 4 microg/mL.

CONCLUSIONS

Based on data from Turkish surveillance studies performed from 2000 onward, high-dose parenteral penicillin G and parenteral/oral amoxicillin may be initial choices for the empiric treatment of uncomplicated pneumococcal pneumonia in Turkey. If these agents cannot be used for any reason, other options include parenteral cefuroxime, ceftriaxone, cefotaxime, newer quinolones, macrolides, and telithromycin. Due to elevated rates of resistance in Turkey, trimethoprim-sulfamethoxazole and tetracyclines are not recommended for empiric use in these infections.

Pharmacodynamic evaluation of tosufloxacin against Streptococcus pneumoniae in an in vitro model simulating serum concentration

We compared the antibacterial effects and the emergence of resistance to tosufloxacin or levofloxacin for Streptococcus pneumoniae by simulating the serum concentration according to the Japanese clinical regimens using an in vitro pharmacokinetic-pharmacodynamic model. For quinolone-susceptible strain ATCC49619, tosufloxacin showed bactericidal activity, given that both the AUC(0-24h)/MIC ratios at the dosage of 150 mg t.i.d. and 300 mg b.i.d. of tosufloxacin tosilate were 138 and 193, and the C(max)/MIC ranges were 7.93-10.2 and 15.9-17.6, respectively, which were greater than those of levofloxacin (100 mg t.i.d. and 200 mg b.i.d.). The greater area above the killing curves (AAKCs) or shorter time to achieve 99.9% killing (99.9% KT) in both models of tosufloxacin than those of levofloxacin was related to their larger AUC(0-24h)/MIC and C(max)/MIC. Exposure of only 100 mg t.i.d. of levofloxacin led to outgrowth of the parC mutants, which were twofold less susceptible to levofloxacin than the parent strain. Neither of the tosufloxacin tosilate regimens resulted in isolation of resistant mutants of this strain. For the parC mutant strain D-3197, both the AUC(0-24h)/MIC and C(max)/MIC ratios of tosufloxacin were greater than those of levofloxacin, which resulted in comparable or better bactericidal activity as compared to those of levofloxacin. However, both fluoroquinolones and both regimens led to outgrowth of resistant mutants, which possessed a mutation in gyrA in addition to parC. In conclusion, tosufloxacin is superior to levofloxacin in bactericidal activity against S. pneumoniae in the Japanese clinical regimens, especially in the quinolone-susceptible strain, without emergence of resistant subpopulations.

Evaluation of the BD Phoenix SMIC/ID, a new streptococci identification and antimicrobial susceptibility panel, for potential routine use in a university-based clinical microbiology laboratory

We evaluated the new BD Phoenix automated microbiology system (Becton Dickinson Diagnostic Systems, Sparks, MD) SMIC/ID-4 panel for routine identification (ID) and antimicrobial susceptibility testing (AST) of streptococci in a university-based laboratory. Clinical isolates of Streptococcus pneumoniae (n = 92), Streptococcus pyogenes (n = 24), and Streptococcus agalactiae (n = 10) were collected, and comparisons were made with the routine manual methods used in our microbiology laboratory for ID and susceptibility testing. ID concordance with manual methods was 85.9%, 95.8%, and 90.0% for S. pneumoniae, S. pyogenes, and S. agalactiae, respectively. With respect to AST concordance for S. pneumoniae and beta-hemolytic streptococci (S. pyogenes and S. agalactiae) using Phoenix and standard broth microdilution panels, overall essential agreement was 93.0% and 97.5%, respectively, whereas overall category agreement was 92.4% and 98.9%, respectively. Major and minor error rates for S. pneumoniae and beta-hemolytic streptococci were 0.5% and 0.3%, and 7.1% and 0.8%, respectively. Very major errors were not observed in this study. Mean time for ID and AST test completion was 13.6 +/- 1.6, 10.7 +/- 2.4, and 11.2 +/- 2.3 h for S. pneumoniae, S. pyogenes, and S. agalactiae, respectively. We have demonstrated that Phoenix ID results show high agreement with manual ID and that AST performance was equivalent to standard broth microdilution in less time.