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

Evaluation of Antibiotic Prescribing Pattern Using WHO Access, Watch and Reserve Classification in Kinshasa, Democratic Republic of Congo

BACKGROUND

The AWaRe tool was set up by the World Health Organization (WHO) to promote the rational use of antimicrobials. Indeed, this tool classifies antibiotics into four groups: access, watch, reserve and not-recommended antibiotics. In The Democratic Republic of Congo, data on antibiotic dispensing (prescribing) by health professionals according to the AWaRe classification are scarce. In this research work, we aimed to explore antibiotic dispensing pattern from health professionals according to the WHO AWaRe classification to strengthen the national antimicrobial resistance plan.

METHODS

For this purpose, a survey was conducted from July to December 2022 in the district of Tshangu in Kinshasa. From randomly selected drugstores, drug-sellers were interviewed and randomly selected customers attending those drugstores were included in the study for medical prescriptions collection. The prescribed antibiotics were classified into the access, watch, reserve and not-recommended antibiotics group and by antibiotics number by prescription among pharmacies surveyed.

RESULTS

400 medical prescriptions were collected from 80 drugstores and among which, 301 (75.25%) contained antibiotics. Out of 301 prescriptions, we noticed 164 (54.5%) containing one antibiotic, 117 (38.9%) containing two antibiotics, 15 (5%) containing three antibiotics and 5 (1.6%) containing four antibiotics. A total of 463 antibiotics were prescribed and distributed as 169 (36.5%) were from the access group, 200 (43.2%) from the watch group and 94 (20.3%) from not-recommended antibiotics group, respectively. This can explain the fact of emerging bacterial strains, as, according to the WHO recommendations, the access group should be prioritized because of its activity against a wide range of commonly encountered pathogens and its showing low resistance susceptibility compared to antibiotics from other groups. Based on the anatomical, therapeutic and chemical (ATC) classifications, we observed that third generation cephalosporins represented 34.33% of the prescribed antibiotics, followed by penicillins (17.17%), macrolides (7.63%), aminoglycosides (7.36%) and Imidazole (7.36%), thus accounting approximately for 74% of the classes of antibiotics prescribed. Additionally, among them, the most frequently prescribed antibiotics were Ceftriaxone (21.38%), Amoxicillin (11.01%), Gentamycin (5.61%), Amoxicillin-clavulanic acid (5.61%), Azithromycin (4.97%) and Metronidazole (4.75%), thus accounting for approximately 54% of all the prescribed antibiotics.

CONCLUSION

These results highlight the importance of strict implementation of the national plan to combat antimicrobial resistance and the need to train health workers in the correct application of the WHO AWaRe classification.

Antibiogram Development in the Setting of a High Frequency of Multi-Drug Resistant Organisms at University Teaching Hospital, Lusaka, Zambia

Antimicrobial resistance is a global challenge requiring reliable surveillance data collection and use. Prior studies on resistance in Zambia depended on laboratory methods with limited standardization. Since 2015, the University Teaching Hospital (UTH) microbiology laboratory has used the Vitek 2 Compact (bioMerieux, Inc., Marcy-l'Étoile, France) for standardized identification and susceptibility testing. We conducted a cross-sectional study of 2019 bacterial isolates collected from July 2015 to April 2017 to identify bacterial causes of infections, their susceptibility to commonly used antibiotics at UTH, and develop hospital antibiograms with a multidisciplinary team using World Health Organization guidance. We found high levels of antibiotic resistance among Gram negative bacteria. Escherichia coli and Klebsiella pneumoniae were highly resistant to all antibiotics except amikacin and carbapenems. E. coli had susceptibilities of 42.4% to amoxicillin/clavulanic acid, 41.4% to ceftriaxone, 40.2% to ciprofloxacin, and 10.4% to trimethoprim/sulfamethoxazole (TMP/SMX). K. pneumoniae had susceptibilities of 20.7% to amoxicillin/clavulanic acid, 15.6% to ceftriaxone, 48.5% to ciprofloxacin, and 12.3% to TMP/SMX. The high resistance to 3rd generation cephalosporins indicates high rates of beta-lactamase production. This is information that clinicians need to inform clinical decision making and choice of empiric antibiotics and that UTH requires to inform antimicrobial stewardship such as improvements in antibiotic use.

Results from the Survey of Antibiotic Resistance (SOAR) 2015-18 in Tunisia, Kenya and Morocco: data based on CLSI, EUCAST (dose-specific) and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints

OBJECTIVES

To determine antibiotic susceptibility of community-acquired respiratory tract infection (CA-RTI) isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2015-18 from Tunisia, Kenya and Morocco.

METHODS

MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST (dose-specific) and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints.

RESULTS

S. pneumoniae isolates from Tunisia (n = 79), Kenya (n = 44) and Morocco (n = 19) and H. influenzae isolates (n = 74) from Tunisia only were collected and analysed. Low antibiotic susceptibility was observed in S. pneumoniae from Tunisia, with >90% susceptible only to the fluoroquinolones (all breakpoints), penicillin (CLSI IV and EUCAST high-dose) and ceftriaxone (CLSI, EUCAST high-dose and PK/PD breakpoints). In addition, isolate susceptibility in Kenya was >90% to amoxicillin and amoxicillin/clavulanic acid (CLSI and PK/PD breakpoints). Antibiotic activity was highest in Morocco, where ≥89.5% of pneumococci were susceptible to most antibiotics, excluding trimethoprim/sulfamethoxazole (68.4% by CLSI or PK/PD and 79%-84.2% by EUCAST), macrolides (79%-84.2% by all breakpoints) and cefaclor (0% by EUCAST and 52.6% by PK/PD). The majority (≥86.5%) of H. influenzae isolates from Tunisia were susceptible to most antibiotics by all available breakpoints, except ampicillin and amoxicillin (almost one-third were β-lactamase positive), trimethoprim/sulfamethoxazole (51.4%-56.8%), cefaclor (1.4% by PK/PD), cefuroxime (4.1% by EUCAST), macrolides (1.4%-2.7% by PK/PD) and cefdinir (66.2% by PK/PD). 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

Low antibiotic susceptibility was observed in S. pneumoniae from Tunisia, but susceptibility was higher in isolates from Kenya and highest in those from Morocco. H. influenzae from Tunisia were highly susceptible to most antibiotics. These factors are important in decision making for empirical therapy of CA-RTIs.

The Role of PK/PD Analysis in the Development and Evaluation of Antimicrobials

Pharmacokinetic/pharmacodynamic (PK/PD) analysis has proved to be very useful to establish rational dosage regimens of antimicrobial agents in human and veterinary medicine. Actually, PK/PD studies are included in the European Medicines Agency (EMA) guidelines for the evaluation of medicinal products. The PK/PD approach implies the use of in vitro, ex vivo, and in vivo models, as well as mathematical models to describe the relationship between the kinetics and the dynamic to determine the optimal dosing regimens of antimicrobials, but also to establish susceptibility breakpoints, and prevention of resistance. The final goal is to optimize therapy in order to maximize efficacy and minimize side effects and emergence of resistance. In this review, we revise the PK/PD principles and the models to investigate the relationship between the PK and the PD of antibiotics. Additionally, we highlight the outstanding role of the PK/PD analysis at different levels, from the development and evaluation of new antibiotics to the optimization of the dosage regimens of currently available drugs, both for human and animal use.

Improved penicillin susceptibility of Streptococcus pneumoniae and increased penicillin consumption in Japan, 2013-18

OBJECTIVES

To examine the association between penicillin susceptibility of Streptococcus pneumoniae and penicillin consumption in Japan.

METHODS

We used Japan Nosocomial Infection Surveillance data on the susceptibility of S. pneumoniae and sales data obtained from IQVIA Services Japan K.K. for penicillin consumption. We analysed both sets of data by decomposing them into seasonality and chronological trend components. The cross-correlation function was checked using Spearman's rank correlation coefficient to examine the correlation between susceptibility and consumption.

RESULTS

After adjusting for seasonality, the susceptibility of S. pneumoniae to penicillins gradually improved (55.7% in 2013 and 60.6% in 2018, respectively) and penicillin consumption increased during the same period (0.76 defined daily doses per 1,000 inhabitants per day [DID] in 2013, and 0.89 DID in 2018). The results showed positive cross-correlation (coefficient 0.801, p-value < 0.001). In contrast, cephalosporin consumption decreased (3.91 DID in 2013 and 3.19 DID in 2018) and showed negative cross-correlation with susceptibility of S. pneumoniae to penicillins (coefficient -0.981, p-value < 0.001).

CONCLUSIONS

The rates of penicillin-susceptible S. pneumoniae isolates did not negatively correlate with penicillin consumption at the population level. Increased penicillin consumption might not impair the penicillin susceptibility of S. pneumoniae.

Analysis of Haemophilus species in patients with respiratory tract infections in Yaoundé, Cameroon

OBJECTIVES

To identifyHaemophilus species and characterize antimicrobial susceptibility of isolates from patients with respiratory tract infections (RTIs) in Cameroon.

METHODS

Isolates (n = 95) were from patients with RTIs obtained from two Hospitals in Yaoundé, Cameroon. Isolates were identified by biochemical assay, PCR-based method, MALDI-TOF and whole genome sequencing. Antibiotic minimum inhibitory concentrations were determined by E-test.

RESULTS

H. influenzae was the most prevalent species varying from 76.8% to 84.2% according to different methods. The isolates were mainly nontypable (n = 70, 96%). Three isolates of H. influenzae were capsulated (b, e and f). The isolates were genetically diverse and 40 unique sequence types were identified including 11 new ones. Resistance to ampicillin was observed among 55.3% (52/94) and 9% (14/52) produced TEM-1 β-lactamase. PBP3 mutations occurred in 57.7% of ampicillin resistant isolates (30/52). Eleven isolates were chloramphenicol resistant with 80% producing chloramphenicol acetyltransferase (8/10). Four Haemophilus isolates were rifampicin resistant with two mutations in rpoB gene. Five isolates were ciprofloxacin resistant and harbored mutations in the quinolone resistance determining regions of gyrA and parC genes.

CONCLUSION

H. influenzae isolates are highly diverse and show high levels of antibiotic resistance. H. influenzae serotype b is still circulating in the post-vaccination era.

Current status of resistance to antibiotics in the Democratic Republic of the Congo: A review

A review of literature was conducted to assess the prevalence and mechanisms of antibiotic resistance to date, mainly to β-lactam antibiotics, cephalosporins, carbapenems, colistin, and tigecycline in the Democratic Republic of the Congo (DRC). English and French publications were listed and analysed using PubMed/Medline, Google Scholar, and African Journals database between 1 January 1990 and 31 December 2019. For the 30 published articles found: (1) bacterial resistance to antibiotics concerned both Gram-negative and Gram-positive bacteria; (2) multidrug resistance prevalence was the same in half of Streptococcus pneumoniae isolates; (3) a worrying prevalence of methicillin-resistant Staphylococcus aureus (MRSA) was noted, which is associated with co-resistance to several other antibiotics; and (4) resistance to third-generation cephalosporins was very high in Enterobacteriaceae, mainly because of bla_CTX-M-1 group and bla_SHV genes. Data on carbapenem and colistin resistance were not available in DRC until recently. Further work is required to set up a surveillance system for antibiotic resistance in DRC.

Evaluation of the adequacy of the antimicrobial therapy of invasive Haemophilus influenzae infections: A pharmacokinetic/pharmacodynamic perspective

INTRODUCTION

In Europe, non-typeable H. influenzae (NTHi) is the leading cause of invasive H. influenzae disease in adults and is associated with high mortality. The goal of this study was to determine whether current antimicrobial treatments for H. influenzae infection in Spain are suitable based on their probability of achieving pharmacokinetic/pharmacodynamic (PK/PD) targets.

METHODS

Pharmacokinetic parameters for the antibiotics studied (amoxicillin, amoxicillin/clavulanic acid, ampicillin, cefotaxime, ceftriaxone, imipenem and ciprofloxacin) and susceptibility data for H. influenzae were obtained from literature. A Monte Carlo simulation was used to estimate the probability of target attainment (PTA), defined as the probability that at least a specific value of a PK/PD index is achieved at a certain MIC, and the cumulative fraction of response (CFR), defined as the expected population PTA for a specific drug dose and a specific microorganism population.

RESULTS

Regardless of dosing regimen, all antibiotics yielded CFR values of 100% or nearly 100% for all strains, including BL+, BL- and BLNAR, except amoxicillin and ampicillin for BL+. Thus, if an infection is caused by BL+ strains, treatment with amoxicillin and ampicillin has a high probability of failure (CFR≤8%). For standard doses of amoxicillin, amoxicillin/clavulanic acid and imipenem, PK/PD breakpoints were consistent with EUCAST clinical breakpoints. For the other antimicrobials, PK/PD breakpoints were higher than EUCAST clinical breakpoints.

CONCLUSIONS

Our study confirms by PK/PD analysis that, with the antimicrobials used as empirical treatment of invasive H. influenzae disease, a high probability of therapeutic success can be expected.

Results from the Survey of Antibiotic Resistance (SOAR) 2014-16 in Russia

Objectives

To determine antibiotic susceptibility in isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from Russia.

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 279 S. pneumoniae and 279 H. influenzae were collected. Overall, 67.0% of S. pneumoniae were penicillin susceptible by CLSI oral/EUCAST and 93.2% by CLSI intravenous (iv) breakpoints. All were fluoroquinolone susceptible, with amoxicillin, amoxicillin/clavulanic acid and ceftriaxone susceptibility ≥92.8% by CLSI and PK/PD breakpoints. Isolates showed lower susceptibility to cefuroxime, cefaclor, macrolides and trimethoprim/sulfamethoxazole by CLSI criteria: 85.0%, 76.7%, 68.8% and 67.7%, respectively. Generally, susceptibility was slightly lower by EUCAST criteria, except for cefaclor, for which the difference in susceptibility was much greater. Penicillin-resistant isolates had low susceptibility (≤60%) to all agents except fluoroquinolones. All 279 H. influenzae were ceftriaxone susceptible, 15.4% were β-lactamase positive and ≥97.5% were amoxicillin/clavulanic acid susceptible (CLSI, EUCAST and PK/PD breakpoints). Four isolates were fluoroquinolone non-susceptible by current EUCAST criteria. A major discrepancy was found with azithromycin susceptibility between CLSI (99.3%) and EUCAST and PK/PD (2.2%) breakpoints. Trimethoprim/sulfamethoxazole was poorly active (62.7% susceptible).

Conclusions

Susceptibility to penicillin (oral), macrolides and trimethoprim/sulfamethoxazole was low in S. pneumoniae from Russia. However, isolates were fully susceptible to fluoroquinolones and ≥92.8% were susceptible to amoxicillin, amoxicillin/clavulanic acid and ceftriaxone. Isolates of H. influenzae only showed reduced susceptibility to ampicillin, cefaclor, clarithromycin and trimethoprim/sulfamethoxazole. Some differences were detected between CLSI, EUCAST and PK/PD breakpoints, especially with cefaclor, cefuroxime and macrolides. These data suggest further efforts are required to harmonize international breakpoints.

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/sulfamethoxazole was 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.

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

Objectives

To determine antibiotic susceptibility in isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from Ukraine and the Slovak Republic.

Methods

MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints.

Results

S. pneumoniae isolates collected in Ukraine (n = 100) showed susceptibility rates ≥97% for 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 the 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. influenzae was more homogeneous, with susceptibility to amoxicillin/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 β-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 relatively high rate of β-lactamase-negative-ampicillin-resistant (BLNAR) isolates (7.1%; 7/98).

Conclusions

The variability found across these two neighbouring countries illustrates the need to monitor and publish national and local resistance patterns. This information is not only critical for effective empirical therapy but can also be used to help shape and support antimicrobial stewardship efforts in order to limit antibiotic resistance.

Results from the Survey of Antibiotic Resistance (SOAR) 2014-16 in Bulgaria, Romania, Serbia and Croatia

Objectives

To determine antibiotic susceptibility of isolates of Streptococcus pneumoniae (n = 573) and Haemophilus influenzae (n = 345) collected in 2014-16 from Bulgaria, Romania, Serbia and Croatia.

Methods

MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints.

Results

Among S. pneumoniae, susceptibility was generally lowest in Romania and Serbia and highest in Bulgaria. Rates of susceptibility to penicillin (CLSI oral or EUCAST) were 22.3% and 21.8% in Romania and Serbia respectively, 57% in Croatia and 86.6% in Bulgaria. Similarly, macrolide susceptibility using CLSI/EUCAST breakpoints was low in Romania and Serbia (∼28% and 34.5%, respectively), higher in Croatia (55.9%) and highest in Bulgaria (∼75%). Only fluoroquinolones were active against all isolates in all four countries. Susceptibility was higher and variability across countries less pronounced for H. influenzae. Susceptibility by CLSI criteria to amoxicillin/clavulanic acid, azithromycin, cefuroxime, ceftriaxone and fluoroquinolones was ≥98% in all countries. Ampicillin susceptibility ranged from 85.3% in Romania to 100% in Bulgaria. Much greater variability was seen across breakpoints. Susceptibility to azithromycin and cefuroxime using CLSI criteria was ≥98% in all four countries, but was 0%-1% by EUCAST criteria.

Conclusions

The variability in antimicrobial susceptibility using different breakpoints makes it difficult for clinicians to interpret antimicrobial resistance data, and efforts should be made to harmonize breakpoints. The variability found across the four neighbouring countries demonstrates the need to monitor and publish national and local resistance patterns. These findings provide information critical for the selection of appropriate antimicrobial agents for the treatment of S. pneumoniae and H. influenzae.

Results from the Survey of Antibiotic Resistance (SOAR) 2014-16 in the Czech Republic

Objectives

To determine the antibiotic susceptibility of isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from patients with community-acquired respiratory infections in the Czech Republic.

Methods

MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints.

Results

S. pneumoniae isolates (n = 200) showed high rates of susceptibility (>95%) to amoxicillin, amoxicillin/clavulanic acid, penicillin [intravenous (iv) non-meningitis], ceftriaxone, cefuroxime and the fluoroquinolones using CLSI breakpoints. Susceptibility to cefaclor and trimethoprim/sulfamethoxazole was 94%-94.5%, to penicillin (oral) 91.5% and to the macrolides 89.5%. Susceptibility of H. influenzae (n = 197) to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, azithromycin and the fluoroquinolones was ≥98% by CLSI criteria. Rates of susceptibility to the remaining agents were ≥75% except for clarithromycin at 37.1%. Great variability was seen across breakpoints, especially for the macrolides, cefaclor and cefuroxime (oral), 98.0% of H. influenzae showing susceptibility to the latter by CLSI criteria, 69.5% by PK/PD and 1.5% by EUCAST standards. The β-lactamase rate was 13.7% with no β-lactamase-negative-ampicillin-resistant (BLNAR) isolates by CLSI criteria.

Conclusions

Antibiotic resistance among the two major respiratory pathogens remained low in the Czech Republic. These findings support local clinicians in continuing the historically restrictive use of antibiotics in the Czech Republic, with selection of narrower-spectrum agents for the empirical therapy of community-acquired respiratory tract infections. This highlights one of the great benefits of continuous surveillance of antimicrobial resistance: knowledge of current local resistance patterns reduces the need to choose broad-spectrum agents that contribute to increasing resistance worldwide.

A meta-analysis of antimicrobial susceptibility profiles for pneumococcal pneumonia in sub-Saharan Africa

BACKGROUND

Pneumonia causes an enormous burden of childhood disease globally, particularly in low- and middle-income countries. Pneumococcus is the most common bacterial aetiology of pneumonia; however, antimicrobials are limited and may not adequately address the local epidemiology of the region.

AIM

To undertake a review and meta-analysis of pneumonia studies in sub-Saharan Africa to evaluate antimicrobial susceptibility patterns in childhood pneumonia.

METHODS

Articles published in PubMed and Google between 2006 and 2016 which evaluated antimicrobial susceptibility profiles of pneumococcal pneumonia in children in sub-Saharan Africa were identified. The source of specimens, pathogens and antimicrobial susceptibility data were extracted. Pooled analysis of susceptible isolates was conducted using random effects models.

RESULTS

Children from 15 studies and 1634 isolates were included in the meta-analysis. In cases of childhood pneumonia, the mean overall proportion of penicillin susceptibility from invasive specimens of Streptococcus pneumoniae was 85.7% (95% CI 80.1-91.3), and of trimethoprim-sulfamethoxazole was 21.0% (95% CI 5.1-36.9). Compared with all S. pneumoniae specimens, penicillin susceptibility was 68.6% (95% CI 59.6-77.5) and that of trimethoprim-sulfamethoxazole was 26.3% (95% CI 14.1-38.6).

CONCLUSIONS

A high level of heterogeneity was detected, reflecting the paucity of data available. The establishment of national and regional diagnostic platforms to monitor antimicrobial susceptibility profiles for pneumonia as well as other invasive diseases will provide data with which to assess the relevance and adaptation of antimicrobial prescribing recommendations.

Trends in antimicrobial resistance in bloodstream infection isolates at a large urban hospital in Malawi (1998-2016): a surveillance study

Background

Bacterial bloodstream infection is a common cause of morbidity and mortality in sub-Saharan Africa, yet few facilities are able to maintain long-term surveillance. The Malawi-Liverpool-Wellcome Trust Clinical Research Programme has done sentinel surveillance of bacteraemia since 1998. We report long-term trends in bloodstream infection and antimicrobial resistance from this surveillance.

Methods

In this surveillance study, we analysed blood cultures that were routinely taken from adult and paediatric patients with fever or suspicion of sepsis admitted to Queen Elizabeth Central Hospital, Blantyre, Malawi from 1998 to 2016. The hospital served an urban population of 920 000 in 2016, with 1000 beds, although occupancy often exceeds capacity. The hospital admits about 10 000 adults and 30 000 children each year. Antimicrobial susceptibility tests were done by the disc diffusion method according to British Society of Antimicrobial Chemotherapy guidelines. We used the Cochran-Armitage test for trend to examine trends in rates of antimicrobial resistance, and negative binomial regression to examine trends in icidence of bloodstream infection over time.

Findings

Between Jan 1, 1998, and Dec 31, 2016, we isolated 29 183 pathogens from 194 539 blood cultures. Pathogen detection decreased significantly from 327·1/100 000 in 1998 to 120·2/100 000 in 2016 (p<0·0001). 13 366 (51·1%) of 26 174 bacterial isolates were resistant to the Malawian first-line antibiotics amoxicillin or penicillin, chloramphenicol, and co-trimoxazole; 68·3% of Gram-negative and 6·6% of Gram-positive pathogens. The proportions of non-Salmonella Enterobacteriaceae with extended spectrum beta-lactamase (ESBL) or fluoroquinolone resistance rose significantly after 2003 to 61·9% in 2016 (p<0·0001). Between 2003 and 2016, ESBL resistance rose from 0·7% to 30·3% in Escherichia coli, from 11·8% to 90·5% in Klebsiella spp and from 30·4% to 71·9% in other Enterobacteriaceae. Similarly, resistance to ciprofloxacin rose from 2·5% to 31·1% in E coli, from 1·7% to 70·2% in Klebsiella spp and from 5·9% to 68·8% in other Enterobacteriaceae. By contrast, more than 92·0% of common Gram-positive pathogens remain susceptible to either penicillin or chloramphenicol. Meticillin-resistant Staphylococcus aureus (MRSA) was first reported in 1998 at 7·7% and represented 18·4% of S aureus isolates in 2016.

Interpretation

The rapid expansion of ESBL and fluoroquinolone resistance among common Gram-negative pathogens, and the emergence of MRSA, highlight the growing challenge of bloodstream infections that are effectively impossible to treat in this resource-limited setting.

Funding

Wellcome Trust, H3ABionet, Southern Africa Consortium for Research Excellence (SACORE).

Appendectomy as a Risk Factor for Bacteremic Biliary Tract Infection Caused by Antibiotic-Resistant Pathogens

Background/Aims

Recent evidence has suggested that appendix plays a pivotal role in the development and preservation of intestinal immune system. The aim of this study is to examine whether prior appendectomy is associated with an increased risk for the development of antibiotic-resistant bacteria in bacteremia from biliary tract infection (BTI).

Methods

Charts from 174 consecutive cases of bacteremia derived from BTI were retrospectively reviewed. Using multivariate analysis, independent risk factors for development of antibiotic-resistant bacteria were identified among the clinical parameters, including a history of appendectomy.

Results

In total, 221 bacteria strains were identified from 174 BTI events. Of those, 42 antibiotic-resistant bacteria were identified in 34 patients. Multivariate analysis revealed that prior appendectomy (Odds ratio (OR), 3.02; 95% confidence interval (CI), 1.15–7.87; p = 0.026), antibiotic use within the preceding three months (OR, 3.06; 95% CI, 1.26–7.64; p = 0.013), and bilioenteric anastomosis or sphincterotomy (OR, 3.77; 95% CI, 1.51–9.66; p = 0.0046) were independent risk factors for antibiotic-resistant bacteria.

Conclusions

Prior appendectomy was an independent risk factor for the development of antibiotic-resistant bacteria in bacteremia from BTI.