Results from the Survey of Antibiotic Resistance (SOAR) 2011–13 in Ukraine

Objectives: To determine the antibiotic susceptibility of respiratory isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2011–13 from Ukraine. Methods: MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. Results: A total of 134 isolates of S. pneumoniae and 67 of H. influenzae were collected from eight sites in Ukraine. Overall, 87.3% of S. pneumoniae were penicillin susceptible by CLSI oral breakpoints and 99.3% by CLSI iv breakpoints. Susceptibility to amoxicillin/clavulanic acid (amoxicillin), ceftriaxone and levofloxacin was 100% by CLSI and PK/PD breakpoints. Cephalosporin and macrolide susceptibility was ≥95.5% and 88.1%, respectively using CLSI breakpoints. Trimethoprim/sulfamethoxazole was essentially inactive against pneumococci. Of the 67 H. influenzae tested, 4.5% were b-lactamase positive and all H. influenzae were fully susceptible to amoxicillin/ clavulanic acid, ceftriaxone, ciprofloxacin, cefixime and levofloxacin (all breakpoints). Cefuroxime susceptibility was 100% by CLSI but 73.1% by EUCAST and PK/PD breakpoints. A discrepancy was found in macrolide susceptibility between CLSI (100% susceptible), EUCAST (22%–43% susceptible) and PK/PD (0%–22% susceptible) breakpoints. Trimethoprim/sulfamethoxazole was poorly active (59.7% susceptible). Conclusions: Generally, antibiotic resistance was low in respiratory pathogens from Ukraine. However, only amoxicillin/clavulanic acid (amoxicillin), ceftriaxone and levofloxacin were fully active against both species. Trimethoprim/sulfamethoxazole was the least active, particularly against S. pneumoniae. Some susceptibility differences were apparent between CLSI, EUCAST and PK/PD breakpoints, especially with macrolides against H. influenzae. These data suggest that further efforts are required to harmonize these international breakpoints. Future studies are warranted to monitor continued low resistance levels in Ukraine compared with other parts of Eastern Europe

Results from the Survey of Antibiotic Resistance (SOAR) 2016–17 in Ukraine: data based on CLSI, EUCAST (dose-specific) and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints

Objectives: To determine antibiotic susceptibility of Streptococcus pneumoniae and Haemophilus influenzae isolates from community-acquired respiratory tract infections (CA-RTIs) collected in 2016–17 from Ukraine. Methods: MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST (dose-specific) and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. Results: A total of 177 viable clinical isolates, including 78 S. pneumoniae and 99 H. influenzae, were collected. Overall, 98% of S. pneumoniae isolates were susceptible to penicillin by CLSI IV or EUCAST high-dose breakpoints and 73.1% were susceptible by CLSI oral or EUCAST low-dose IV breakpoints. Susceptibility rates of 76.9%–100% were observed for most antibiotics by all breakpoints except trimethoprim/sulfamethoxazole (41%–69.2%) and cefaclor, which showed the greatest difference between breakpoints: 0% by EUCAST, 28.2% by PK/PD and 73.1% by CLSI. All S. pneumoniae isolates were susceptible to amoxicillin/clavulanic acid by CLSI and PK/PD breakpoints. H. influenzae isolates were almost all b-lactamase negative (90.9%). One isolate was blactamase negative and ampicillin resistant (BLNAR) by CLSI and four isolates were BLNAR by EUCAST criteria. Susceptibility of isolates was high (90.9%) by CLSI breakpoints for all antibiotics tested except trimethoprim/ sulfamethoxazole (61.6%). Susceptibility using EUCAST breakpoints was similar for ampicillin (90.9%) and amoxicillin/clavulanic acid (95%) but was low for cefuroxime (oral), where only 10.1% of isolates were susceptible. All S. pneumoniae and H. influenzae isolates were susceptible to the fluoroquinolones by all breakpoints. Susceptibility to ceftriaxone was also 100% for H. influenzae and 91% for S. pneumoniae isolates by all breakpoints. The application of different EUCAST breakpoints for low and higher doses for some of the antibiotics (amoxicillin, amoxicillin/clavulanic acid, ampicillin, penicillin, ceftriaxone, clarithromycin, erythromycin, levofloxacin and trimethoprim/sulfamethoxazole) allowed, for the first time in a SOAR study, the effect of raising the dosage on susceptibility to be quantified. Conclusions: Antibiotic susceptibility in these respiratory tract pathogens was generally high in Ukraine. These data are important for empirical therapy choices in the treatment of CA-RTIs

Results from the Survey of Antibiotic Resistance (SOAR) 2011-14 in the Democratic Republic of Congo, Ivory Coast, Republic of Senegal and Kenya

Objectives: To assess antibiotic susceptibility of community-acquired respiratory tract isolates from Ivory Coast, Kenya, Democratic Republic of Congo (DRC) and Senegal in 2011–14. Methods: Bacterial isolates were collected and MICs determined using Etest® for all antibiotics except erythromycin, for which testing was by disc diffusion. Susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. For macrolide interpretation, CLSI breakpoints were adjusted for incubation in CO2. Results: Susceptibility to penicillin (using CLSI oral or EUCAST breakpoints) was low among isolates of Streptococcus pneumoniae from the DRC and Kenya (17.4% and 19%, respectively) but higher among isolates from the Ivory Coast (70%) and Senegal (85.7%). Penicillin susceptibility using CLSI iv breakpoints was higher in all countries, but still only 69.6% in the DRC. Macrolide susceptibility (based on CLSI erythromycin disc diffusion breakpoints) was also low in Kenya (∼65%) but 87%–100% elsewhere.Haemophilus influenzae were only collected in the DRC and Senegal, with β-lactamase prevalence of 39% and 4%, respectively. Furthermore, β-lactamase-negative ampicillin-resistant (BLNAR) isolates were found in DRC (four isolates, 17%), but only two isolates were found in Senegal (by EUCAST definition). Amoxicillin/clavulanic acid in vitro susceptibility was 73.9% in the DRC and 100% in Senegal based on CLSI breakpoints, but this reduced to 65.2% in the DRC when BLNAR rates were considered. Clarithromycin susceptibility was \u3e95% in both countries. Conclusions: There was considerable variability in antibiotic susceptibility among the African countries participating in the surveillance programme. Thus, continued surveillance is necessary to track future changes in antibiotic resistance. Use of EUCAST versus CLSI breakpoints showed profound differences for cefaclor and ofloxacin against S. pneumoniae, with EUCAST showing lower susceptibility

Results from the Survey of Antibiotic Resistance (SOAR) 2011–13 in Ukraine

Objectives: To determine the antibiotic susceptibility of respiratory isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2011–13 from Ukraine. Methods: MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. Results: A total of 134 isolates of S. pneumoniae and 67 of H. influenzae were collected from eight sites in Ukraine. Overall, 87.3% of S. pneumoniae were penicillin susceptible by CLSI oral breakpoints and 99.3% by CLSI iv breakpoints. Susceptibility to amoxicillin/clavulanic acid (amoxicillin), ceftriaxone and levofloxacin was 100% by CLSI and PK/PD breakpoints. Cephalosporin and macrolide susceptibility was ≥95.5% and 88.1%, respectively using CLSI breakpoints. Trimethoprim/sulfamethoxazole was essentially inactive against pneumococci. Of the 67 H. influenzae tested, 4.5% were b-lactamase positive and all H. influenzae were fully susceptible to amoxicillin/ clavulanic acid, ceftriaxone, ciprofloxacin, cefixime and levofloxacin (all breakpoints). Cefuroxime susceptibility was 100% by CLSI but 73.1% by EUCAST and PK/PD breakpoints. A discrepancy was found in macrolide susceptibility between CLSI (100% susceptible), EUCAST (22%–43% susceptible) and PK/PD (0%–22% susceptible) breakpoints. Trimethoprim/sulfamethoxazole was poorly active (59.7% susceptible). Conclusions: Generally, antibiotic resistance was low in respiratory pathogens from Ukraine. However, only amoxicillin/clavulanic acid (amoxicillin), ceftriaxone and levofloxacin were fully active against both species. Trimethoprim/sulfamethoxazole was the least active, particularly against S. pneumoniae. Some susceptibility differences were apparent between CLSI, EUCAST and PK/PD breakpoints, especially with macrolides against H. influenzae. These data suggest that further efforts are required to harmonize these international breakpoints. Future studies are warranted to monitor continued low resistance levels in Ukraine compared with other parts of Eastern Europe

Results from the Survey of Antibiotic Resistance (SOAR) 2014–16 in Ukraine and the Slovak Republic

S. pneumoniae isolates collected in Ukraine (n"100) showed susceptibility 97% fratesor amoxicillin, amoxicillin/clavulanic acid, penicillin [intravenous (iv) non-meningitis] and fluoroquinolones, between 83% and 86% for oral penicillin, macrolides and cefaclor, and 75% for trimethoprim/sulfamethoxazole. Susceptibility was substantially lower in the Slovak Republic (n"95). All isolates were susceptible to ratesthe fluoroquinolones, but susceptibility to penicillin, amoxicillin, amoxicillin/clavulanic acid, cefuroxime and trimethoprim/sulfamethoxazole varied between 61% and 64%, with only 44% of isolates susceptible to the macrolides. Susceptibility of H. influenzaewasmorehomogeneous,with susceptibilitytoamoxicillin/clavulanic acid,ceftriaxone,cefuroxime, azithromycin and the fluoroquinolones seen in .90% of isolates by CLSI criteria in both countries. Much greater variability was seen across breakpoints, especially for azithromycin, cefaclor and cefuroxime. The b-lactamase rate was 5.1% (5/98) in the Slovak Republic and 7.3% (7/96) in Ukraine, but the Slovak Republic also had a relativelyhighrateofb-lactamase-negative-ampicillin-resistant(BLNAR)isolates(7.1%;7/98)

Results from the Survey Of Antibiotic Resistance (SOAR) 2014-16 in Greece

Objectives: To determine antimicrobial susceptibility in isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from patients with community-acquired respiratory tract infections in Greece. Methods: MICs were determined by CLSI broth microdilution and susceptibility assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. Results: A total of 99 S. pneumoniae and 52 H. influenzae isolates were collected. Overall, 36.4%of S. pneumoniae were penicillin susceptible by CLSI oral/EUCAST and 88.9% by CLSI intravenous (iv) breakpoints. All were fluoroquinolone susceptible with ≥ 94% of isolates also susceptible to amoxicillin, amoxicillin/clavulanic acid and ceftriaxone by CLSI and PK/PD breakpoints. Trimethoprim/sulfamethoxazole, cefuroxime, cefaclor and macrolides were less active, with rates of susceptibility of 83.8%, 69.7%, 50.5% and 49.5%, respectively, by CLSI. Generally susceptibility was the same or slightly lower by EUCAST, but the cefaclor difference was much greater. Among H. influenzae, 15.4% of isolates were β-lactamase positive. Susceptibility to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime and the fluoroquinolones was seen in > 95% of isolates by CLSI criteria. Susceptibility to azithromycin was seen in 94.2% of isolates using CLSI breakpoints, but clarithromycin susceptibility was lower (61.5%). However, susceptibility to both macrolides was seen in < 5% of isolates by PK/PD and EUCAST criteria. Susceptibility to trimethoprim/sulfamethoxazolewas seen in 71.2%of isolates. Conclusions: Owing to the high prevalence of macrolide resistance among S. pneumoniae and the reduced activity of clarithromycin against H. influenzae, it appears that these agents are not appropriate as monotherapy for community-acquired pneumonia in Greece. Amoxicillin/clavulanic acid, on the other hand, maintained excellent in vitro activity and, as opposed to the similarly effective fluoroquinolones, is safe to use in paediatric patients. © The Author(s) 2018. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved

Effect of some antibiotics on pigmentation in Serratia marcescens

Serratia marcescens is characterized by its ability to produce a red pigment called prodigiosin. It is well known that there are some substances affecting pigmentation in bacteria. Cefoxitin, erythromycin, tobramycin, co-trimoxazole, imipenem and nitrofurantoin were found to have an inhibitory effect on pigmentation in a S. marcescens strain isolated from urine. it was also shown that the LD50 dose determined by inoculation of eight-week-old BALB/c mice with serial dilutions of overnight cultures of pigmented and nonpigmented variants was lower (LD50 = 300 X 10(3.94)) in the nonpigmented variant than in the pigmented one (LD50 = 300 x 10(5.58)). In addition, the Sereny test showed that in contrast to the pigmented variant, the nonpigmented variant caused keratitis in guinea pig eye