Association of incidence of type 1 diabetes with mortality from infectious disease and with antibiotic susceptibility at a country level

To investigate the association between country incidence of type 1 diabetes and mortality from infectious disease and antibiotic susceptibility. An ecological study to explore the relationship at a country level of the reported incidence of type 1 diabetes (DiaMond) to infectious disease mortality (World Health Organisation) and to antibiotic susceptibility (Alexander Project). There were significant negative correlations between the incidence of type 1 diabetes and mortality for all infectious diseases studied. There were also significant positive correlations between the incidence of type 1 diabetes and antibiotic susceptibilities of Strep. pneumoniae, but not to those of Haem. influenzae. Since infectious disease mortality and antibiotic susceptibility are surrogate markers for bacterial exposure, our results provide support for a negative association between bacterial exposure in a community and its incidence of type 1 diabetes. The consistency of our results as well as the highly statistically significant results of most of the associations studied reinforces the validity of our findings.

Antimicrobial activity of the pleuromutilin antibiotic BC-3781 against bacterial pathogens isolated in the SENTRY antimicrobial surveillance program in 2010

BC-3781 is a novel semisynthetic pleuromutilin antibiotic inhibiting bacterial protein synthesis. BC-3781 has completed a phase 2 clinical trial in acute bacterial skin and skin structure infections (ABSSSI). Its antibacterial spectrum additionally covers the predominant pathogens causing community-acquired bacterial pneumonia (CABP). In this study, the antibacterial activity of BC-3781 was evaluated against a contemporary collection of 10,035 bacterial isolates predominately causing ABSSSI and CABP, among other infections, collected within the SENTRY Antimicrobial Surveillance Program worldwide in 2010. BC-3781 exhibited potent activity against organisms commonly isolated from ABSSSI such as Staphylococcus aureus (MIC50/90, 0.12/0.12 μg/ml; 99.8% inhibited at ≤0.5 μg/ml), beta-hemolytic streptococci (MIC50/90, 0.03/0.03 μg/ml; 99.3% inhibited at ≤0.5 μg/ml), and coagulase-negative staphylococci (CoNS; MIC50/90, 0.06/0.12 μg/ml; 97.8% inhibited at ≤1 μg/ml). BC-3781 displayed similar MIC distributions among methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) S. aureus strains. BC-3781 was also active against Enterococcus faecium, with 76.3% of vancomycin-susceptible and 97.0% of vancomycin-resistant isolates being inhibited at BC-3781 concentrations of ≤1 μg/ml. Beta-hemolytic and viridans group streptococci were highly susceptible to BC-3781, with 99.3% and 96.7% of isolates inhibited at ≤0.5 μg/ml, respectively. Further, activity of BC-3781 against Streptococcus pneumoniae (MIC50/90, 0.12/0.25 μg/ml), Haemophilus influenzae (MIC50/90, 1/2 μg/ml), and Moraxella catarrhalis (MIC50/90, 0.12/0.25 μg/ml) was not negatively influenced by β-lactamase production or resistance to other antimicrobial classes tested. In all, BC-3781 displayed a very potent antibacterial profile including the most prevalent bacterial pathogens causing ABSSSI and CABP, thus warranting further clinical development of this antibiotic in these and possibly other indications.

Longitudinal nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in indigenous Australian and Alaska native children with bronchiectasis

Background

Indigenous children in Australia and Alaska have very high rates of chronic suppurative lung disease (CSLD)/bronchiectasis. Antibiotics, including frequent or long-term azithromycin in Australia and short-term beta-lactam therapy in both countries, are often prescribed to treat these patients. In the Bronchiectasis Observational Study we examined over several years the nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in these two PCV7-vaccinated populations.

Methods

Indigenous children aged 0.5–8.9 years with CSLD/bronchiectasis from remote Australia (n = 79) and Alaska (n = 41) were enrolled in a prospective cohort study during 2004–8. At scheduled study visits until 2010 antibiotic use in the preceding 2-weeks was recorded and nasopharyngeal swabs collected for culture and antimicrobial susceptibility testing. Analysis of respiratory bacterial carriage and antibiotic resistance was by baseline and final swabs, and total swabs by year.

Results

Streptococcus pneumoniae carriage changed little over time. In contrast, carriage of Haemophilus influenzae declined and Staphylococcus aureus increased (from 0% in 2005–6 to 23% in 2010 in Alaskan children); these changes were associated with increasing age. Moraxella catarrhalis carriage declined significantly in Australian, but not Alaskan, children (from 64% in 2004–6 to 11% in 2010). While beta-lactam antibiotic use was similar in the two cohorts, Australian children received more azithromycin. Macrolide resistance was significantly higher in Australian compared to Alaskan children, while H. influenzae beta-lactam resistance was higher in Alaskan children. Azithromycin use coincided significantly with reduced carriage of S. pneumoniae, H. influenzae and M. catarrhalis, but increased carriage of S. aureus and macrolide-resistant strains of S. pneumoniae and S. aureus (proportion of carriers and all swabs), in a ‘cumulative dose-response’ relationship.

Conclusions

Over time, similar (possibly age-related) changes in nasopharyngeal bacterial carriage were observed in Australian and Alaskan children with CSLD/bronchiectasis. However, there were also significant frequency-dependent differences in carriage and antibiotic resistance that coincided with azithromycin use.

Antimicrobial activity of ceftaroline and comparator agents tested against bacterial isolates causing skin and soft tissue infections and community-acquired respiratory tract infections isolated from the Asia-Pacific region and South Africa (2010)

Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil, is a cephalosporin with in vitro bactericidal activity against resistant Gram-positive organisms including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant strains of Streptococcus pneumoniae, and common Gram-negative organisms, including wild-type Enterobacteriaceae. We evaluated the in vitro activity of ceftaroline and selected comparator agents against bacterial isolates collected from patients with skin and soft tissue infections (SSTI) and community-acquired respiratory tract infections (CARTI) in the Asia-Pacific region and South Africa. A total of 2351 isolates, 1100 from SSTI and 1251 from CARTI, were collected from 25 medical centers distributed across 8 countries as part of the 2010 AWARE ceftaroline surveillance program and tested for susceptibility by reference broth microdilution methods. Ceftaroline was very active against S. aureus (MIC50/90, 0.25/1 μg/mL; 93.4% susceptible), including MRSA (MIC50/90, 1/2 μg/mL; 80.6% susceptible). Against β-hemolytic streptococci, ceftaroline demonstrated greater activity (MIC90, 0.015 μg/mL) than penicillin (MIC90, 0.06 μg/mL). Ceftaroline was also highly active against viridans group streptococci (MIC90, 0.12 μg/mL). Similarly to ceftriaxone, ceftaroline activity against Escherichia coli (MIC50/90, >32/>32 μg/mL) and Klebsiella spp. (MIC50/90, 0.12/>32 μg/mL) was compromised by the high prevalence of isolates with an ESBL phenotype in the region, particularly in China. Ceftaroline was the most potent β-lactam tested against S. pneumoniae (MIC50/90 of 0.015/0.25 μg/mL; 99.8% susceptible by Clinical and Laboratory Standards Institute [CLSI] criteria), and it was also highly potent against Haemophilus influenzae (MIC50/90, ≤ 0.008/0.03 μg/mL; 100% susceptible by CLSI criteria). Ceftaroline was also active against H. parainfluenzae (MIC50/90, ≤ 0.008/0.015 μg/mL) and Moraxella catarrhalis (MIC50/90, 0.06/0.12 μg/mL). In summary, ceftaroline showed potent in vitro activity against a large collection of bacterial isolates (2351) associated with SSTI and CARTI from the Asia-Pacific region and South Africa.

[Microbial structure of acute bacterial conjunctivitis]

Microbiological investigation of 124 patients with acute conjunctivitis which were treated in one of Tbilisi policlinics in 2010-12 years, was performed; microbial structure containing 124 microbial strains of different species was detected. Namely, following species of microorganisms were isolated: S. aureus - 35 strains (28,2%), Str. pneumoniae - 10 strains (8,1%), S. epidermidis - 6 strains (4,8%), Ps. aeruginosa - 24 strains (19,4%), Moraxella catarrhalis - 21 strains (16,9%), Haemophilus influenzae biogroup aegipticus - 17 strains (13,7%), and Klebsiella pneumoniae - 11 strains (8,9%). Identification of microorganisms was performed using classic methods of microbiological explorations and test systems API (bio Meriux). Study of sensitivity/resistance to antibiotics (ciprofloxacin, levofloxacin, tobramicin, norfoloxacin, moxifloxacin) containing in eye drops, was performed by diffusion in agar. High level of resistance to this antibiotic was found. As a result it is recommended to perform microbiological investigation in each case of acute conjunctivitis, to receive rational treatment.

AWARE Ceftaroline Surveillance Program (2008-2010): trends in resistance patterns among Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in the United States

Ceftaroline fosamil, the prodrug form of the active metabolite ceftaroline, is a new broad-spectrum parenteral cephalosporin with antibacterial activity against the prevalent respiratory pathogens Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus. Bacterial resistance surveillance (5330 isolates) was conducted in the United States between 2008 and 2010 to assess the in vitro activity of ceftaroline and comparator antibacterial agents against invasive respiratory isolates of S. pneumoniae (3329 isolates), H. influenzae (1545 isolates), and M. catarrhalis (456 isolates). All organisms were cultured from patient infections in 71 US hospital laboratories and were submitted to a central reference monitor for broth microdilution testing by Clinical and Laboratory Standards Institute reference methods. Against S. pneumoniae, ceftaroline inhibited 98.7% of strains at the susceptible breakpoint of ≤ 0.25 µg/mL (50% minimum inhibitory concentration [MIC(50)], 0.01 µg/mL; 90% MIC [MIC(90)], 0.12 µg/mL) and was 16-fold more active than ceftriaxone (MIC(90), 2 µg/mL). Among 70 ceftriaxone-resistant pneumococcal isolates, all were inhibited by ≤ 0.5 µg/mL of ceftaroline. Haemophilus influenzae (MIC(50), ≤ 0.008 µg/mL; MIC(90), 0.015 µg/mL) and M. catarrhalis (MIC(50), 0.06 µg/mL; MIC(90), 0.12 µg/mL) were very susceptible to ceftaroline regardless of β-lactamase production. Whereas the high-level of activity of ceftaroline was maintained against S. pneumoniae and H. influenzae from 2008 through 2010, increased rates of nonsusceptibility were observed for amoxicillin/clavulanate, erythromycin, and levofloxacin among S. pneumoniae and for trimethoprim/sulfamethoxazole and azithromycin among H. influenzae. In summary, ceftaroline resistance surveillance (Assessing Worldwide Antimicrobial Resistance Evaluation [AWARE] Program) in the United States (2008-2010) documented in vitro sustained potency and spectrum against Gram-positive and Gram-negative pathogens known to cause community-acquired bacterial pneumonia.

Summary of ceftaroline activity against pathogens in the United States, 2010: report from the Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) surveillance program

The Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) surveillance program is a sentinel resistance monitoring system designed to track the activity of ceftaroline and comparator agents. In the United States, a total of 8,434 isolates were collected during the 2010 surveillance program from 65 medical centers distributed across the nine census regions (5 to 10 medical centers per region). All organisms were isolated from documented infections, including 3,055 (36.2%) bloodstream infections, 2,282 (27.1%) respiratory tract infections, 1,965 (23.3%) acute bacterial skin and skin structure infections, 665 (7.9%) urinary tract infections, and 467 (5.5%) miscellaneous other infection sites. Ceftaroline was the most potent β-lactam agent tested against staphylococci. The MIC(90) values were 1 μg/ml for methicillin-resistant Staphylococcus aureus (MRSA; 98.4% susceptible) and 0.5 μg/ml for methicillin-resistant coagulase-negative staphylococci (CoNS). Ceftaroline was 16- to 32-fold more potent than ceftriaxone against methicillin-susceptible staphylococcal strains. All staphylococcus isolates (S. aureus and CoNS) were inhibited at ceftaroline MIC values of ≤ 2 μg/ml. Ceftaroline also displayed potent activity against streptococci (MIC(90), 0.015 μg/ml for beta-hemolytic streptococci; MIC(90), 0.25 μg/ml for penicillin-resistant Streptococcus pneumoniae). Potent activity was also shown against Gram-negative pathogens (Haemophilus influenzae, Haemophilus parainfluenzae, and Moraxella catarrhalis). Furthermore, wild-type strains of Enterobacteriaceae (non-extended-spectrum β-lactamase [ESBL]-producing strains and non-AmpC-hyperproducing strains) were often susceptible to ceftaroline. Continued monitoring through surveillance networks will allow for the assessment of the evolution of resistance as this new cephalosporin is used more broadly to provide clinicians with up-to-date information to assist in antibiotic stewardship and therapeutic decision making.

[Antimicrobial susceptibility of community-acquired respiratory tract pathogens isolated from adults in China during 2009 and 2010]

OBJECTIVE

To investigate the drug-resistance rates of community-acquired respiratory tract pathogens isolated from adults in China during 2009 and 2010.

METHODS

A total of 1793 strains (S. aureus 421, S. pneumoniae 420, K. pneumoniae 404, H. influenzae 313, other Streptococcus. spp 149, and M. catarrhalis 86) of non-duplicated community-acquired respiratory tract pathogens were isolated from 11 hospitals in 6 cities. The MIC values were determined by the broth microdilution method, and the production of β-lactamase was tested using a nitrocefin-based test.

RESULTS

All of the S.aureus isolates were methicillin-sensitive (MSSA). Of the MSSA isolates, less than 1% (4/421) was resistant to β-lactamase inhibitor combinations, about 13.1% (55/421) and 9% (38/421) resistant to levofloxacin and moxifloxacin, and 57% (240/421), 53.2% (224/421), and 88.7% (373/421) resistant to azithromycin, clarithromycin, and penicillin, respectively. No S. aureus isolates resistant to vancomycin were detected in this study. Based on different criteria, the percentages of penicillin-sensitive S. pneumoniae (PSSP), penicillin-intermediate S. pneumoniae (PISP), and penicillin-resistant S. pneumoniae (PRSP) were 24.4% (102/420), 27.3% (115/420), 48.3% (203/420) (Oral) and 1.9% (8/420), 9% (38/420), 89.1% (374/420) (parenteral), respectively. The resistance rates of S. pneumonia to azithromycin, clarithromycin, cefaclor, cefuroxime, ceftriaxone and amoxicillin with clavulanic acid were 88.2% (370/420), 87.4% (367/420), 45.3% (190/420), 41.9% (176/420), 10.2% (43/420), and 5.2% (22/420), respectively. About 2.6% (11/420) and 0.2% (1/420) of S. pneumonia isolates were resistant to levofloxacin and moxifloxacin. More than 70% (104/149) of β-hemolytic streptococci isolates were resistant to azithromycin and clarithromycin, and about 10.1% (15/149) of isolates were resistant to levofloxacin. The resistance rates of K.pneumonia to most antibiotics were > 20% (81/404), and that of ceftazidime was lower than cefuroxime, cefaclor, and ceftriaxone. The mean prevalence value of ESBL producing K. pneumonia was 38.8% (157/404), with significantly regional variations. More than 90% of H. influenza and M. catarrhalis were susceptible to most antibiotics, with resistance rate of < 5% (16/313, H. influenza; 4/86, M. catarrhalis). The mean productions of β-lactamase in H. influenza and M. catarrhalis were 13.1% (41/313) and 91.7% (79/86), respectively.

CONCLUSIONS

The percentage of PRSP increased significantly, and the resistance rates of community-acquired respiratory tract pathogens to common antibiotics such as macrolide and cephalosporins increased gradually. New fluoroquinolones such as moxifloxacin showed a high antimicrobial activity against most of the respiratory pathogens.

C4-alkylthiols with activity against Moraxella catarrhalis and Mycobacterium tuberculosis

Antimicrobial resistance represents a global threat to healthcare. The ability to adequately treat infectious diseases is increasingly under siege due to the emergence of drug-resistant microorganisms. New approaches to drug development are especially needed to target organisms that exhibit broad antibiotic resistance due to expression of β-lactamases which is the most common mechanism by which bacteria become resistant to β-lactam antibiotics. We designed and synthesized 20 novel monocyclic β-lactams with alkyl- and aryl-thio moieties at C4, and subsequently tested these for antibacterial activity. These compounds demonstrated intrinsic activity against serine β-lactamase producing Mycobacterium tuberculosis wild type strain (Mtb) and multiple (n=6) β-lactamase producing Moraxella catarrhalis clinical isolates.

Studies on the antibacterial effects of statins--in vitro and in vivo

Background

Statin treatment has been associated with a beneficial outcome on respiratory tract infections. In addition, previous in vitro and in vivo experiments have indicated favorable effects of statins in bacterial infections.

Aim

The aim of the present study was to elucidate possible antibacterial effects of statins against primary pathogens of the respiratory tract.

Methods

MIC-values for simvastatin, fluvastatin and pravastatin against S. pneumoniae, M. catarrhalis and H. influenzae were determined by traditional antibacterial assays. A BioScreen instrument was used to monitor effects of statins on bacterial growth and to assess possible synergistic effects with penicillin. Bacterial growth in whole blood and serum from healthy volunteers before and after a single dose of simvastatin, fluvastatin and penicillin (positive control) was determined using a blood culture system (BactAlert).

Findings

The MIC-value for simvastatin against S pneumoniae and M catarrhalis was 15 µg/mL (36 mmol/L). Fluvastatin and Pravastatin showed no antibacterial effect in concentrations up to 100 µg/mL (230 µmol/L). Statins did not affect growth or viability of H influenzae. Single doses of statins given to healthy volunteers did not affect growth of pneumococci, whereas penicillin efficiently killed all bacteria.

Conclusions

Simvastatin at high concentrations 15 µg/mL (36 µmol/L) rapidly kills S pneumoniae and M catarrhalis. However, these concentrations by far exceed the concentrations detected in human blood during simvastatin therapy (1–15 nmol/L) and single doses of statins given to healthy volunteers did not improve antibacterial effects of whole blood. Thus, a direct bactericidal effect of statins in vivo is probably not the mechanism behind the observed beneficial effect of statins against various infections.

Multistep resistance development studies of ceftaroline in gram-positive and -negative bacteria

Ceftaroline, the active component of the prodrug ceftaroline fosamil, is a novel broad-spectrum cephalosporin with bactericidal activity against Gram-positive and -negative isolates. This study evaluated the potential for ceftaroline and comparator antibiotics to select for clones of Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis with elevated MICs. S. pneumoniae and S. pyogenes isolates in the present study were highly susceptible to ceftaroline (MIC range, 0.004 to 0.25 μg/ml). No streptococcal strains yielded ceftaroline clones with increased MICs (defined as an increase in MIC of >4-fold) after 50 daily passages. Ceftaroline MICs for H. influenzae and M. catarrhalis were 0.06 to 2 μg/ml for four strains and 8 μg/ml for a β-lactamase-positive, efflux-positive H. influenzae with a mutation in L22. One H. influenzae clone with an increased ceftaroline MIC (quinolone-resistant, β-lactamase-positive) was recovered after 20 days. The ceftaroline MIC for this isolate increased 16-fold, from 0.06 to 1 μg/ml. MICs for S. aureus ranged from 0.25 to 1 μg/ml. No S. aureus isolates tested with ceftaroline had clones with increased MIC (>4-fold) after 50 passages. Two E. faecalis isolates tested had ceftaroline MICs increased from 1 to 8 μg/ml after 38 days and from 4 to 32 μg/ml after 41 days, respectively. The parental ceftaroline MIC for the one K. pneumoniae extended-spectrum β-lactamase-negative isolate tested was 0.5 μg/ml and did not change after 50 daily passages.

[Rational antibiotic therapy of acute upper respiratory tract infections]

Overuse of antibiotics is a major cause of bacterial resistance. Inappropriate and unnecessary antibiotic therapies are particularly frequent in the treatment of respiratory tract infections, which are viral in origin in about 80% of cases. This review work presents the principles of rational antibiotic therapy of acute upper respiratory tract infections, namely pharyngotonsillitis, otitis media and sinusitis according to Polish Recommendations 2010.

Nasopharyngeal flora and drug susceptibility in children with macrolide therapy

OBJECTIVES/HYPOTHESIS

Low-dose, long-term administration of macrolides (macrolide therapy) has been used as an effective treatment for chronic respiratory tract diseases. The authors reported on the nasopharyngeal flora in children treated with macrolide therapy.

STUDY DESIGN

Prospective study.

METHODS

Nasopharyngeal cultures were obtained from 73 children with chronic rhinosinusitis and/or otitis media with effusion at the end of the low-dose administration of clarithromycin (macrolide group). As control subjects, 98 children with chronic rhinosinusitis and/or otitis media with effusion who were not given macrolides were also included in the study. The culture results were evaluated with respect to antimicrobial susceptibility patterns, risk factors for carriage of erythromycin-resistant Streptococcus pneumoniae, and the clinical efficacy of the therapy.

RESULTS

The macrolide therapy did not have a significant effect on the incidence or the susceptibility patterns of potential pathogens except for Moraxella catarrhalis. Most of children in the macrolide group possessed a normal flora compared with the control children. The risk factors for carriage of erythromycin-resistant S pneumoniae were male gender in the macrolide group and age under 6 years and use of antimicrobial drugs other than macrolides in the control group. The clinical efficacy of the therapy was independent of carriage of erythromycin-resistant S pneumoniae.

CONCLUSION

Macrolide therapy has little effect on carriage of drug-resistant pathogens, and the efficacy of the therapy depends on the anti-inflammatory effect of the drugs, which is independent of their antimicrobial effect.

[Resistance study of community respiratory pathogens isolated in China from 2005 to 2007]

OBJECTIVE

To investigate the antimicrobial resistance of community respiratory pathogens isolated in China.

METHODS

The strains of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, S. pyogenes were isolated from patients with community-acquired respiratory tract infections at 14 Chinese hospitals from 2005 to 2007. Etest and disk diffusion methods were used to survey the susceptibility of 14 antibiotics against these strains. These antibiotics included penicillin G, ampicillin, amoxicillin/clavulanic acid, cefaclor, cefprozil, ceftriaxone, cefepime, levofloxacin, gatifloxacin, ciprofloxacin, tetracycline, clindamycin, erythromycin and trimethoprim/sulfamethoxazole (SXT).

RESULTS

A total of 1870 strains were collected including S. pneumoniae (n = 997), S. pyogenes (n = 176), H. influenzae (n = 499) and M. catarrhalis (n = 198). The 2005 - 2007 prevalence of penicillin-susceptible S. pneumoniae (PSSP) were 92.6%, 73.9%, 74.1% and penicillin-intermediate S. pneumoniae (PISP) 4.5%, 9.5%, 14.3% and penicillin-resistant S. pneumoniae (PRSP) 2.9%, 16.6%, 11.6% respectively. 36.9% of S. pneumoniae strains isolated from <or= 6 years old children were penicillin-non-susceptive isolates (PNSSP) and < 22.0% of PNSSP isolated from other age groups. The susceptible rates of beta-lactamase antibiotics to PRSP and PISP isolates were less than 25.0% and 49.2% respectively. From 48.5% to 98.6% PSSP isolates were susceptible to beta-lactamase antibiotics. The susceptible rates of PNSSP and PSSP to erythromycin, tetracycline and SXT were below 7.1% and 32.1% respectively. About 95% S. pneumoniae were susceptible to ciprofloxacin, levofloxacin and gatifloxacin. All of S. pyogenes isolates were susceptible to beta-lactamase antibiotics, and 16.7%, 27.1% and 15.6% Of S. pyogenes isolates were susceptible to erythromycin. 8.5%, 19.9%, 15.3% of H. influenzae and 57.4%, 78.8%, 95.5% of M. catarrhalis produced beta-lactamase during the 3-year period. The susceptible rates of cefepime, ceftriaxone, gatifloxacin, levofloxacin and ciprofloxacin to H. influenzae and M. catarrhalis were >or= 92.9%.

CONCLUSIONS

Antimicrobial resistance in S. pneumoniae is rising. The prevalence of PNSSP isolated from children < or = 6 years old is higher than other age groups. Amoxicillin-clavulanic acid, ceftriaxone, cefepime, gatifloxacin and levofloxacin remain highly active against common community respiratory pathogens.

Synthesis of N-substituted 5-iodouracils as antimicrobial and anticancer agents

This study reports the synthesis of some substituted 5-iodouracils and their bioactivities. Alkylation of 5-iodouracils gave predominately N1-substituted-(R)-5-iodouracil compounds 7a-d (R = n-C₄H₉, s-C₄H₉, CH₂C₆H₁₁, CH₂C₆H₅) together with N1,N3-disubstituted (R) analogs 8a-b (R = n-C₄H₉, CH₂C₆H₁₁). Their antimicrobial activity was tested against 27 strains of microorganisms using the agar dilution method. The analogs 7a, 7c and 7d displayed 25-50% inhibition against Branhamella catarrhalis, Neisseria mucosa and Streptococcus pyogenes at 0.128 mg/mL. No antimalarial activity was detected for any of the analogs when tested against Plasmodium falciparum (T9.94). Their anticancer activity was also examined. Cyclohexylmethyl analogs 7c and 8b inhibited the growth of HepG2 cells. Significantly, N1,N3-dicyclohexylmethyl analog 8b displayed the most potent anticancer activity, with an IC₅₀ of 16.5 μg/mL. These 5-iodouracil analogs represent a new group of anticancer and antibacterial agents with potential for development for medicinal applications.

Microbiology of otitis media: a moving target

The microbiology of acute otitis media (AOM) is linked to the nasopharyngeal commensal flora. This respiratory ecosystem undergoes various selective pressures, such as antibiotic consumption and vaccine use. Socio-economic conditions also influence the bacterial composition of the nasopharynx. Streptococcus pneumoniae, non-encapsulated Haemophilus influenzae, Moraxella catarrhalis, and group A Streptococcus are the leading causes of bacterial AOM worldwide. This paper will discuss the causes and consequences of recent shifts in the underlying microbiology of AOM.

Changes in antibiotic resistance of respiratory pathogens in the Slovak Republic

Respiratory tract infections are one of the most common reasons for public sickness rate. Even though they are usually virus-caused, antibiotic prescription is mostly used in primary care. The increase of resistance of bacterial strains observed in the last decade has much to do with this. This increase is connected mainly with the increasing antibiotics consumption and their selective pressure. That is why in many countries, there is an effort to stop this increase by reducing the useless prescription from etiology point of view. This paper points out a more careful approach to acute bacterial rhinosinusitis treatment in the community, taking into consideration the worsening condition of antibiotics resistance in Slovakia and Europe.

[Drug susceptibility of bacteria isolated from pediatric respiratory infections at general practitioners' clinics to pediatric antibiotics]

Four major causative bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pyogenes) of pediatric respiratory infections, 295 clinical isolates in total, were isolated at general practitioners' clinics in Sendai city, and evaluated the drug susceptibility to seven antibiotics for pediatric. Penicillin-resistant S. pneumoniae and penicillin-intermediate S. pneumoniae (PRSP-PISP) were 55.8% of all S. pneumoniae isolates. The MIC90 of penicillin and cephalosporin antibiotics in S. pneumoniae were good, 0.5-1 microg/mL, however, macrolide-resistant strains remarkably increased. As for H. influenzae, 50.0% of all isolates were ampicillin-intermediate and -resistant (MIC: > or = 2 microg/mL), the MIC90s of cephalosporin antibiotics had large differences between 0.5 to 8 microg/mL, and generally less susceptibility was shown to other antibiotics. M. catarrhalis showed less susceptibility to amoxicillin which behaved unstably to penicillinase, on the other hand, the MIC90s of other antibiotics were relatively good, 0.25-1 microg/mL. S. pyogenes remarkably tend to be resistant to macrolide antibiotics, however, the MIC90s of penicillin and cephalosporin antibiotics were very good, 0.03-0.06 microg/mL. Pediatric respiratory infections are required a treatment which results in inhibition of drug-resistant bacteria. Based on the results of drug susceptibility testing, we should make a proper selection of antibiotics by reference to disposition such as drug concentration in serum and transfer into cells.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2005)]

From October 2005 to September 2006, we collected the specimen from 366 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 411 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in infection, 406 strains were examined. The isolated bacteria were: Staphylococcus aureus 70, Streptococcus pneumoniae 85, Haemophilus influenzae 78, Pseudomonas aeruginosa (non-mucoid) 46, P. aeruginosa (mucoid) 14, Klebsiella pneumoniae 21, and Moraxella subgenus Branhamella catarrhalis 40. Of 70 S. aureus strains, those with 2 microg/ml or less of MIC of oxacillin (methicillin-susceptible S. aureus: MSSA) and those with 4 microg/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) were 38 (54.3%) and 32 (45.7%) strains, respectively. Against MSSA, imipenem had the most potent antibacterial activity and inhibited the growth of 37 strains (97.4%) at 0.063 microg/ml or less. Against MRSA, arbekacin and vancomycin showed the most potent activity and inhibited the growth of all the strains at 1 microg/ml. Carbapenems showed the most potent activities against S. pneumoniae and in particular, panipenem inhibited the growth of all the strains at 0.063 microg/ml or less. Faropenem also had a preferable activity and inhibited the growth of all the strains at 0.25 microg/ml. In contrast, there were high-resistant strains (MIC: over 128 microg/ml) for erythromycin (38.1%) and clindamycin (22.6%). Against H. influenzae, levofloxacin showed the most potent activity and its MIC90 was 0.063 microg/ml or less. Meropenem showed the most potent activity against P. aeruginosa (mucoid) and its MIC90 was 0.5 microg/ml. Against P. aeruginosa (non-mucoid), arbekacin had the most potent activity and its MIC90 was 8 microg/ml. Against K. pneumoniae, cefozopran was the most potent activity and inhibited the growth of all the strains at 0.063 microg/ml or less. Also, all the antibacterial agents except ampicillin generally showed a potent activity against M. (B.) catarrhalis and the MIC90 of them were 2 microg/ml or less. The approximately half the number (53.6%) of the patients with respiratory infection were aged 70 years or older. Bacterial pneumonia and chronic bronchitis accounted for 44.3% and 29.8% of all the respiratory infection, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (15.4%), S. pneumoniae (23.4%), and H. influenzae (21.3%). S. aureus (25.4%) and S. pneumoniae (18.0%) also were frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from the patients were S. pneumoniae (22.0%) and H. influenzae (21.4%). The bacteria frequently isolated from the patients treated with macrolides were S. pneumoniae and P. aeruginosa, and their isolation frequencies were each 35.3%.

[Antimicrobial susceptibility of 80 Moraxella catarrhalis strains isolated in the children's hospital of Tunis]

Eighty non-repetitive strains of Moraxella catarrhalis, isolated in Tunis Children's Hospital during five years from 1998 to 2002, were tested for their antimicrobial susceptibility, 95% of these strains were isolated from lung samples: 57.5% from trachea products, 35% from sputum and 2.5% from bronchial washings. The majority of strains (72%) were obtained from children under two years old. Antimicrobial susceptibility study showed that 95% of stains were beta-lactamase-producing, therefore they were penicillin G and amoxicillin resistant with high MICs. MIC(90) of penicillin G and amoxicillin of beta-lactamase-producing strains were respectively greater than 32 and 6 mg/l, these MIC decrease with addition of clavulanic acid. In fact, all strains studied were susceptible to the association amoxicillin-clavulanic acid as well as to cefotaxime. Concerning the other antimicrobial groups percentages of resistant strains found were as follows: erythromycin 3.75%, trimethoprim-sulfamethoxazol 12.5% and tetracycline 1.25%. Finally, all strains were susceptible to chloramphenicol, rifampicin and ciprofloxacin.

Global and local variations in antimicrobial susceptibilities and resistance development in the major respiratory pathogens

Acute respiratory tract infections, such as bacterial pneumonia and acute exacerbations of chronic bronchitis, have been identified by the World Health Organisation as the leading global infectious cause of death. An increasing prevalence of antibiotic resistance has been identified worldwide in the three major bacterial respiratory pathogens -Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae. The selection and spread of resistance is to some degree inevitable and the importance of monitoring its progress has led to the instigation of numerous international, regional and national surveillance programmes. The results from surveillance studies show wide variations in susceptibility rates, both geographically and over time, highlighting the need for local resistance prevalence data in order to guide empirical prescribing and to identify areas in which medical need for new agents is greatest.

National and regional assessment of antimicrobial resistance among community-acquired respiratory tract pathogens identified in a 2005-2006 U.S. Faropenem surveillance study

Surveillance studies conducted in the United States over the last decade have revealed increasing resistance among community-acquired respiratory pathogens, especially Streptococcus pneumoniae, that may limit future options for empirical therapy. The objective of this study was to assess the scope and magnitude of the problem at the national and regional levels during the 2005-2006 respiratory season (the season when community-acquired respiratory pathogens are prevalent) in the United States. Also, since faropenem is an oral penem being developed for the treatment of community-acquired respiratory tract infections, another study objective was to provide baseline data to benchmark changes in the susceptibility of U.S. respiratory pathogens to the drug in the future. The in vitro activities of faropenem and other agents were determined against 1,543 S. pneumoniae isolates, 978 Haemophilus influenzae isolates, and 489 Moraxella catarrhalis isolates collected from 104 U.S. laboratories across six geographic regions during the 2005-2006 respiratory season. Among S. pneumoniae isolates, the rates of resistance to penicillin, amoxicillin-clavulanate, and cefdinir were 16, 6.4, and 19.2%, respectively. The least effective agents were trimethoprim-sulfamethoxazole (SXT) and azithromycin, with resistance rates of 23.5 and 34%, respectively. Penicillin resistance rates for S. pneumoniae varied by region (from 8.7 to 22.5%), as did multidrug resistance rates for S. pneumoniae (from 8.8 to 24.9%). Resistance to beta-lactams, azithromycin, and SXT was higher among S. pneumoniae isolates from children than those from adults. beta-Lactamase production rates among H. influenzae and M. catarrhalis isolates were 27.4 and 91.6%, respectively. Faropenem MICs at which 90% of isolates are inhibited were 0.5 mug/ml for S. pneumoniae, 1 mug/ml for H. influenzae, and 0.5 mug/ml for M. catarrhalis, suggesting that faropenem shows promise as a treatment option for respiratory infections caused by contemporary resistant phenotypes.