Widespread Detection of Yersiniabactin Gene Cluster and Its Encoding Integrative Conjugative Elements (ICEKp) among Nonoutbreak OXA-48-Producing Klebsiella pneumoniae Clinical Isolates from Spain and the Netherlands

In this study, we determined the presence of virulence factors in nonoutbreak, high-risk clones and other isolates belonging to less common sequence types associated with the spread of OXA-48-producing Klebsiella pneumoniae clinical isolates from The Netherlands (n = 61) and Spain (n = 53). Most isolates shared a chromosomally encoded core of virulence factors, including the enterobactin gene cluster, fimbrial fim and mrk gene clusters, and urea metabolism genes (ureAD). We observed a high diversity of K-Locus and K/O loci combinations, KL17 and KL24 (both 16%), and the O1/O2v1 locus (51%) being the most prevalent in our study. The most prevalent accessory virulence factor was the yersiniabactin gene cluster (66.7%). We found seven yersiniabactin lineages-ybt 9, ybt 10, ybt 13, ybt 14, ybt 16, ybt 17, and ybt 27-which were chromosomally embedded in seven integrative conjugative elements (ICEKp): ICEKp3, ICEKp4, ICEKp2, ICEKp5, ICEKp12, ICEKp10, and ICEKp22, respectively. Multidrug-resistant lineages-ST11, ST101, and ST405-were associated with ybt 10/ICEKp4, ybt 9/ICEKp3, and ybt 27/ICEKp22, respectively. The fimbrial adhesin kpi operon (kpiABCDEFG) was predominant among ST14, ST15, and ST405 isolates, as well as the ferric uptake system kfuABC, which was also predominant among ST101 isolates. No convergence of hypervirulence and resistance was observed in this collection of OXA-48-producing K. pneumoniae clinical isolates. Nevertheless, two isolates, ST133 and ST792, were positive for the genotoxin colibactin gene cluster (ICEKp10). In this study, the integrative conjugative element, ICEKp, was the major vehicle for yersiniabactin and colibactin gene clusters spreading. IMPORTANCE Convergence of multidrug resistance and hypervirulence in Klebsiella pneumoniae isolates has been reported mostly related to sporadic cases or small outbreaks. Nevertheless, little is known about the real prevalence of carbapenem-resistant hypervirulent K. pneumoniae since these two phenomena are often separately studied. In this study, we gathered information on the virulent content of nonoutbreak, high-risk clones (i.e., ST11, ST15, and ST405) and other less common STs associated with the spread of OXA-48-producing K. pneumoniae clinical isolates. The study of virulence content in nonoutbreak isolates can help us to expand information on the genomic landscape of virulence factors in K. pneumoniae population by identifying virulence markers and their mechanisms of spread. Surveillance should focus not only on antimicrobial resistance but also on virulence characteristics to avoid the spread of multidrug and (hyper)virulent K. pneumoniae that may cause untreatable and more severe infections.

Fecal carriage of extended-spectrum beta-lactamase-producing Enterobacterales in healthy Spanish schoolchildren

Background

Extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) are a serious threat among emerging antibiotic resistant bacteria. Particularly, the number of cases of ESBL-E infections reported in children has been increasing in recent years, and approved antibiotic treatments for this age group are limited. However, information regarding the prevalence of colonization in European children, risk factors associated with colonization, and the characteristics of the colonizing strains is scarce. The aims of this study were to determine the prevalence of ESBL-E colonization in fecal samples of apparently healthy schoolchildren, to identify lifestyle routines associated with colonization, and to characterize clonal relationships and mechanisms of resistance in ESBL-E isolates.

Methods

A cohort of 887 healthy children (3-13  years old) from seven primary and secondary schools in the Madrid metropolitan area was recruited between April-June 2018, and sociodemographic information and daily habits were collected. Fecal samples were screened for ESBL-E carriage in selective medium. ESBL-E isolates were further characterized by assessing molecular epidemiology (PFGE and MLST), ESBL gene carriage, and antibiotic resistance profile. This information was analyzed in conjunction with the metadata of the participants in order to identify external factors associated with ESBL-E carriage.

Results

Twenty four ESBL-E, all but one Escherichia coli, were detected in 23 children (prevalence: 2.6%; 95% CI: 1.6-3.6%). Of these, seven contained the bla_CTX-M-14 allele, five the bla_CTX-M-15, five the bla_SHV-12, three the bla_CTX-M-27, three the bla_CTX-M-32, and one the bla_CTX-M-9. Significant clonal diversity was observed among the isolates that grouped into 22 distinct clusters (at <85% similarity of PFGE profile). ESBL-producing E. coli isolates belonged to 12 different STs, with ST10 (25%) and ST131 (17%) being the most frequent. Apart from ß-lactams, resistance to trimethoprim/sulfamethoxazole (46%), ciprofloxacin (33%), levofloxacin (33%), tobramycin (21%), and gentamicin (8%) were the most frequently detected.

Conclusion

The prevalence of ESBL-E in the studied cohort of children was lower than the average colonization rate previously detected in Europe for both children and adults. E. coli was the main ESBL-producing species detected and CTX-M were the most frequently identified ESBLs. High ST diversity suggests polyclonal dissemination. Compared to other STs, ST131 isolates were associated with resistance to various antimicrobials.

Phenotypic and molecular characterization of IMP-producing Enterobacterales in Spain: Predominance of IMP-8 in Klebsiella pneumoniae and IMP-22 in Enterobacter roggenkampii

Objectives

Little is known about IMP-producing Enterobacterales (IMP-Ent) in Europe. We analyzed at genomic and phenotypic level IMP-Ent isolates circulating in Spain in a 9-year period.

Materials and methods

IMP-Ent isolates submitted to our reference laboratory were included. Antibiotic susceptibility was performed using microdilution method (EUCAST), and IMP-carbapenemase activity was measured with carbapenemase inhibitors, the β-CARBA method, the modified Hodge test (MHT), and the modified carbapenemase inhibition method (mCIM). All isolates collected were sequenced for high-resolution single-nucleotide polymorphism (SNP) typing, core genome multilocus sequence typing (cgMLST), and resistome analysis.

Results

Fifty IMP-Ent isolates, collected from 19 hospitals in 13 Spanish provinces, were detected: Klebsiella pneumoniae (IMP-Kpn) (24; 48%), Enterobacter roggenkampii (13; 26%), Enterobacter hormaechei (8, 16%), Klebsiella oxytoca (two; 4%), Enterobacter asburiae (one, 2%), Serratia marcescens (one; 2%) and Escherichia coli (one; 2%). All isolates were positive by the MHT and β-CARBA tests; 48 (96%) were mCIM positive; 12 (24%) and 26 (52%) displayed positive inhibition with dipicolinic (meropenem) and EDTA (ertapenem), respectively. Five IMP-carbapenemase types were identified: IMP-8 (22; 44%), IMP-22 (17; 34%), IMP-13 (7; 14%), IMP-28 (two; 4%), and IMP-15 (two; 4%), predominating IMP-8 in K. pneumoniae and IMP-22 in E. roggenkampii. IMP-28 was exclusively identified in K. oxytoca and IMP-15 in E. hormaechei. Predominant STs were ST405 (29.2%), ST15 (25%) and ST464 (20.8%) in IMP-Kpn; ST96 (100%) in E. roggenkampii and ST182 (62.5%) in E. hormachei. Colistin and amikacin were the most active non-carbapenem antibiotics against IMP-Ent.

Conclusion

IMP-Ent isolates remain infrequent in Spain, although in recent years have been circulating causing nosocomial outbreaks, being IMP-8-producing K. pneumoniae and IMP-22-producing E. roggenkampii the most frequently detected in this study. Inhibition with EDTA or dipicolinic acid presented false negative results in some IMP-producing strains. Active microbiological and molecular surveillance is essential for a better comprehension and control of IMP-Ent dissemination.

Clinical management of cUTI, cIAI, and HABP/VABP attributable to carbapenem-resistant Gram-negative infections in Spain

Introduction. Carbapenem-resistant Gram-negative (CRGN) infections are a major public health problem in Spain, often implicated in complicated, healthcare-associated infections that require the use of potentially toxic antibacterial agents of last resort. The objective of this study was to assess the clinical management of complicated infections caused by CRGN bacteria in Spanish hospitals. Methods. The study included: 1) a survey assessing the GN infection and antibacterial susceptibility profile in five participating Spanish hospitals and 2) a non-interventional, retrospective single cohort chart review of 100 patients with complicated urinary tract infection (cUTI), complicated intra-abdominal infection (cIAI), or hospital-acquired bacterial pneumonia/ventilator-associated bacterial pneumonia (HABP/VABP) attributable to CRGN pathogens. Results. In the participating hospitals CRGN prevalence was 9.3% amongst complicated infections. In the retrospective cohort, 92% of infections were healthcare-associated, and Klebsiella pneumoniae and Pseudomonas aeruginosa were the most common pathogens. OXA was the most frequently detected carbapenemase type (71.4%). We found that carbapenems were frequently used to treat cUTI, cIAI, HABP/VABP caused by CRGN pathogens. Carbapenem use, particularly in combination with other agents, persisted after confirmation of carbapenem resistance. Clinical cure was 66.0%, mortality during hospitalization 35.0%, mortality at the time of chart review 62.0%, and 6-months-post-discharge readmission 47.7%. Conclusion. Our results reflect the high burden and unmet needs associated with the management of complicated infections attributable to CRGN pathogens in Spain and highlight the urgent need for enhanced clinical management of these difficult-to-treat infections.

Emergence of NDM-producing Klebsiella pneumoniae and Escherichia coli in Spain: phylogeny, resistome, virulence and plasmids encoding blaNDM-like genes as determined by WGS

OBJECTIVES

NDM carbapenemases have spread worldwide. However, little information exists about the impact of NDM-producing Enterobacteriaceae in Spain. By WGS, we sought to elucidate the population structure of NDM-like-producing Klebsiella pneumoniae and Escherichia coli in Spain and to determine the plasmids harbouring blaNDM-like genes.

METHODS

High-resolution SNP typing, core-genome MLST and plasmid reconstruction (PlasmidID) were performed on 59 NDM-like-producing K. pneumoniae and 8 NDM-like-producing E. coli isolated over an 8 year period in Spain.

RESULTS

Five major epidemic clones of NDM-producing K. pneumoniae caused five important nationwide outbreaks: ST437/NDM-7, ST437/NDM-1, ST147/NDM-1, ST11/NDM-1 and ST101/NDM-1; in contrast, the spread of NDM-producing E. coli was polyclonal. Three blaNDM types were identified: blaNDM-1, 61.2%; blaNDM-7, 32.8%; and blaNDM-5, 6%. Five K. pneumoniae isolates co-produced other carbapenemases (three blaOXA-48 and two blaVIM-1). The average number of acquired resistance genes was higher in K. pneumoniae than in E. coli. The plasmids encoding blaNDM-like genes belonged to IncFII, IncFIB, IncX3, IncR, IncN and IncC types, of which IncF, IncR and IncC were associated with MDR. The genetic surroundings of blaNDM-like genes showed a highly variable region upstream of ISAba125.

CONCLUSIONS

In recent years NDM-producing K. pneumoniae and E. coli have emerged in Spain; the spread of a few high-risk K. pneumoniae clones such as ST437/NDM-7, ST437/NDM-1, ST147/NDM-1, ST11/NDM-1 and ST101/NDM-1 have caused several interregional outbreaks. In contrast, the spread of NDM-producing E. coli has been polyclonal. Plasmid types IncFII, IncFIB, IncX3, IncR, IncN and IncC carried blaNDM, and the same IncX3 plasmid was detected in K. pneumoniae and E. coli.

Carbapenemase-producing Pseudomonas aeruginosa in Spain: interregional dissemination of the high-risk clones ST175 and ST244 carrying blaVIM-2, blaVIM-1, blaIMP-8, blaVIM-20 and blaKPC-2

Carbapenemase-producing (CP) Pseudomonas aeruginosa is rare compared with mutation-driven carbapenem-resistance, but this situation may be changing. A collection of CP P. aeruginosa isolates was characterized in this study. In 2016, 232 unduplicated carbapenem-resistant P. aeruginosa isolates, of which 71 (30.6%) carried carbapenemase genes, were submitted to the Spanish antibiotic reference laboratory and were further analysed by whole-genome sequencing (WGS). Of the 71 CP P. aeruginosa, 39 (54.9%) carried bla_VIM-2, 14 (19.7%) bla_VIM-1, 8 (11.3%) bla_IMP-8, 6 (8.5%) bla_VIM-20, 2 (2.8%) bla_VIM-2 plus bla_KPC-2, one (1.4%) bla_IMP-13 and one (1.4%) bla_VIM-1 plus bla_IMP-18. Four sequence types (ST175, ST244, ST815 and ST155) encompassed 83.1% of the 71 CP P. aeruginosa; ST175 was detected in hospitals from seven provinces. Using core genome multilocus sequence typing (cgMLST), four clusters were detected: Cluster 1 included nine ST815/VIM-2 isolates; Cluster 2 included five ST175/VIM-2 isolates; Cluster 3 included seven ST244 isolates (five VIM-2 and two VIM-2 plus KPC-2); and Cluster 4 included 11 ST175 isolates (seven VIM-2 and four IMP-8). The average number of acquired resistance genes was significantly higher in the bla_VIM-1-carying isolates (7.1 ± 0.94) than in the bla_VIM-2-carrying isolates (4.5 ± 0.20). CP P. aeruginosa isolates are spreading in Spain, mainly due to the dissemination of high-risk clones such as ST175 and ST244 producing VIM and IMP carbapenemases. Emergence of CP P. aeruginosa is a cause of clinical and epidemiological concern.

Interregional spread in Spain of linezolid-resistant Enterococcus spp. isolates carrying the optrA and poxtA genes

The emergence of linezolid-resistant Enterococcus spp. (LRE) due to transferable resistance determinants is a matter of concern. To understand the contribution of the plasmid-encoded optrA and poxtA genes to the emergence of LRE, clinical isolates from different Spanish hospitals submitted to the Spanish Reference Laboratory from 2015-2018 were analysed. Linezolid resistance mechanisms were screened in all isolates by PCR and sequencing. Genetic relatedness of Enterococcus spp. carrying optrA and poxtA was studied by PFGE and MLST. Antimicrobial susceptibility was tested by broth microdilution using EUCAST standards. A total of 97 LRE isolates were studied, in 94 (96.9%) of which at least one resistance determinant was detected; 84/97 isolates (86.6%) presented a single resistance mechanism as follows: 45/84 (53.6%) carried the optrA gene, 38/84 (45.2%) carried the G2576T mutation and 1/84 (1.2%) carried the poxtA gene. In addition, 5/97 isolates (5.2%) carried both optrA and the G2576T mutation and 5/97 (5.2%) carried both optrA and poxtA. The optrA gene was more frequent in Enterococcus faecalis (83.6%) than Enterococcus faecium (11.1%) and was mainly associated with community-acquired urinary tract infections. Carriage of the poxtA gene was more frequent in E. faecium (13.9%) than E. faecalis (1.6%). Among the optrA-positive E. faecalis isolates, two main clusters were detected by PFGE. These two clusters belonged to ST585 and ST480 and were distributed throughout 11 and 6 Spanish provinces, respectively. This is the first description of LRE carrying the poxtA gene in Spain, including the co-existence of optrA and poxtA in five isolates.

The clinical and cost impact of switching to fingolimod versus other first line injectable disease-modifying therapies in patients with relapsing multiple sclerosis

BACKGROUND

There is limited evidence on the effectiveness and healthcare costs of switching to fingolimod versus another first line injectable therapy (FLIT) in patients with relapsing multiple sclerosis (RMS) who have already been treated with FLIT.

OBJECTIVE

The objectives of the study were to assess the annualized relapse rate (ARR), socio-demographic and clinical characteristics, persistence and adherence rates, healthcare resource utilization and cost among patients with RMS who either switch to fingolimod or another FLIT in routine clinical practice.

METHODS

A multicenter, observational, retrospective chart review was conducted across eight clinics in Canada between 1 May 2011 and 30 June 2013. The data was collected from two cohorts: patients who switched to fingolimod and patients who switched to FLIT from a previous FLIT.

RESULTS AND CONCLUSIONS

A total of 124 patients were included in the study: 82 and 42 switched to fingolimod and FLIT, respectively. There were no significant differences in the patient characteristics at the date of switch except for number of previous disease-modifying therapies (DMTs) which was higher in the fingolimod cohort (fingolimod: 1.52; FLIT: 1.10, p < .001). The ARR during the first year of switching was numerically higher in the FLIT cohort compared to the fingolimod cohort (FLIT: 0.9 [95% CI 0.3-1.6]; fingolimod: 0.3 [95% CI 0.1-0.5]). The negative binomial model adjusted for the number of previous DMTs confirmed a statistically significant difference in ARR between the fingolimod and FLIT cohorts at 12 months of follow-up (p = .012). In the fingolimod cohort, 20.7% of patients experienced at least one relapse compared to 38.1% in the FLIT cohort. In both groups, a high proportion of patients (>90%) showed good treatment adherence (≥80% of prescribed doses).

Carbapenem-resistant Citrobacter spp. isolated in Spain from 2013 to 2015 produced a variety of carbapenemases including VIM-1, OXA-48, KPC-2, NDM-1 and VIM-2

Objectives

There is little information about carbapenemase-producing (CP) Citrobacter spp. We studied the molecular epidemiology and microbiological features of CP Citrobacter spp. isolates collected in Spain (2013-15).

Methods

In total, 119 isolates suspected of being CP by the EUCAST screening cut-off values were analysed. Carbapenemases and ESBLs were characterized using PCR and sequencing. The genetic relationship among Citrobacter freundii isolates was studied by PFGE.

Results

Of the 119 isolates, 63 (52.9%) produced carbapenemases, of which 37 (58.7%) produced VIM-1, 20 (31.7%) produced OXA-48, 12 (19%) produced KPC-2, 2 (3.2%) produced NDM-1 and 1 (1.6%) produced VIM-2; 9 C. freundii isolates co-produced VIM-1 plus OXA-48. Fourteen isolates (22.2%) also carried ESBLs: 8 CTX-M-9 plus SHV-12, 2 CTX-M-9, 2 SHV-12 and 2 CTX-M-15. Fifty-seven isolates (90.5%) were C. freundii, 4 (6.3%) were Citrobacter koseri, 1 (1.6%) was Citrobacter amalonaticus and 1 (1.6%) was Citrobacter braakii. By EUCAST breakpoints, eight (12.7%) of the CP isolates were susceptible to the four carbapenems tested. In the 53 CP C. freundii analysed by PFGE, a total of 44 different band patterns were observed. Four PFGE clusters were identified: cluster 1 included eight isolates co-producing VIM-1 and OXA-48; blaVIM-1 was carried in a class 1 integron (intI-blaVIM-1-aacA4-dfrB1-aadA1-catB2-qacEΔ1/sul1) and blaOXA-48 was carried in a Tn1999.2 transposon.

Conclusions

We observed the clonal and polyclonal spread of CP Citrobacter spp. across several Spanish geographical areas. Four species of Citrobacter spp. produced up to five carbapenemase types, including co-production of VIM-1 plus OXA-48. Some CP Citrobacter spp. isolates were susceptible to the four carbapenems tested, a finding with potential clinical implications.

Colonization with Enterobacteriaceae-Producing ESBLs, AmpCs, and OXA-48 in Wild Avian Species, Spain 2015-2016

Antibiotic resistance is a global threat of complex and changeable epidemiology. The role of wild birds in the dissemination of antibacterial resistance might be underestimated. We studied the cloacal colonization by cefotaxime-resistant Enterobacteriaceae in 668 wild birds in Spain. Eighty-eight wild birds (13.2%) of 28 species carried cefotaxime-resistant isolates; 58 of them (8.7%) carried extended-spectrum β-lactamases (ESBLs) and 15 (2.5%) plasmid-mediated AmpCs of the bla_CIT family. The 58 ESBLs belonged to the CTX-M-1 group (63.9%), CTX-M-9 group (23%), and SHV-group (13.1%). Pulsed field gel electrophoresis (PFGE) analysis of the Escherichia coli isolates revealed a high degree of genetic diversity since 44 different PFGE patterns were observed among the 54 cefotaxime-resistant isolates analyzed. Two clusters were detected with a genetic linkage >90%: Cluster 1 included nine CTX-M-15-producing isolates of ST23, and Cluster 2 included four isolates producing plasmid mediated AmpC of the CIT family of ST744. In addition, five birds were colonized by OXA-48- and CTX-M-15-producing isolates: three Klebsiella pneumoniae (isolated from Eurasian eagle-owl, lesser kestrel, and common buzzard), one E. coli (common buzzard), and one Enterobacter cloacae (cattle egret). Also, an mcr-1-positive and CIT-producing E. coli isolate colonized a black vulture. By multilocus sequence typing, the three OXA-48-producing K. pneumoniae isolates belonged to the high-risk human clones ST11 (two) and ST15 (one); the OXA-48-producing E. coli belonged to ST23, and the mcr-1-positive E. coli belonged to ST162. The diversity of eating patterns and migratory habits of the multiple avian species, capable of carrying multiresistant bacteria as observed in this study, may contribute to their global dissemination from human sources.

The spread of KPC-producing Enterobacteriaceae in Spain: WGS analysis of the emerging high-risk clones of Klebsiella pneumoniae ST11/KPC-2, ST101/KPC-2 and ST512/KPC-3

OBJECTIVES

We analysed the microbiological traits and population structure of KPC-producing Enterobacteriaceae isolates collected in Spain between 2012 and 2014. We also performed a comparative WGS analysis of the three major KPC-producing Klebsiella pneumoniae clones detected.

METHODS

Carbapenemase and ESBL genes were sequenced. The Institut Pasteur MLST scheme was used. WGS data were used to construct phylogenetic trees, to identify the determinants of resistance and to de novo assemble the genome of one representative isolate of each of the three major K. pneumoniae clones.

RESULTS

Of the 2443 carbapenemase-producing Enterobacteriaceae isolates identified during the study period, 111 (4.5%) produced KPC. Of these, 81 (73.0%) were K. pneumoniae and 13 (11.7%) were Enterobacter cloacae. Three major epidemic clones of K. pneumoniae were identified: ST11/KPC-2, ST101/KPC-2 and ST512/KPC-3. ST11/KPC-2 differed from ST101/KPC-2 and ST512/KPC-3 by 27 819 and 6924 SNPs, respectively. ST101/KPC-2 differed from ST512/KPC-3 by 28 345 SNPs. Nine acquired resistance genes were found in ST11/KPC-2, 11 in ST512/KPC-3 and 13 in ST101/KPC-2. ST101/KPC-2 had the highest number of virulence genes (20). An 11 bp deletion at the end of the mgrB sequence was the cause of colistin resistance in ST512/KPC-3.

CONCLUSIONS

KPC-producing Enterobacteriaceae are increasing in Spain. Most KPC-producing K. pneumoniae isolates belonged to only five clones: ST11 and ST512 caused interregional spread, ST101 caused regional spread and ST1961 and ST678 produced independent hospital outbreaks. ST101/KPC-2 had the highest number of resistance and virulence genes. ST101/KPC-2 and ST512/KPC-3 were recently implicated in the spread of KPC in Italy.

Carbapenemase-producing Escherichia coli is becoming more prevalent in Spain mainly because of the polyclonal dissemination of OXA-48

OBJECTIVES

The objective of this study was to analyse the microbiological traits and the population structure of carbapenemase-producing (CP) Escherichia coli isolates collected in Spain between 2012 and 2014.

METHODS

Two-hundred-and-thirty-nine E. coli isolates non-susceptible to carbapenems were studied. The carbapenemase genes and the phylogenetic groups were characterized using PCR. MLST was carried out using the typing schemes of the University of Warwick and the Institut Pasteur. The diversity of the population structure was estimated by calculating a simple diversity index (SDI).

RESULTS

One-hundred-and-twenty-one isolates (50.6%) produced carbapenemases, of which 87 (71.9%) were OXA-48, 27 (22.3%) were VIM-1, 4 (3.3%) were KPC-2, 2 (1.7%) were NDM and 1 (0.8%) was IMP-22; 4 isolates were collected in 2012, 40 in 2013 and 77 in 2014. Ertapenem was more sensitive than imipenem or meropenem for screening for OXA-48-producing E. coli. Using the Warwick typing scheme, 59 different STs were identified, the most prevalent being ST131 (16.5%). The population diversity was higher among VIM-1-producing isolates (SDI = 81.5%) than among OXA-48-producing isolates (SDI = 44.8%). The Pasteur scheme had a higher discrimination capability (SDI = 55.4%) than the Warwick scheme (SDI = 48.8%).

CONCLUSIONS

A progressive increase in the prevalence of CP E. coli was observed, mainly due to the dissemination of OXA-48 producers. The most sensitive method for detecting decreased susceptibility of CP E. coli to carbapenems was disc diffusion with ertapenem using the EUCAST screening cut-offs. The spread of CP E. coli was due to a polyclonal population. The Pasteur scheme showed the highest discrimination power. Surveillance is crucial for the early detection of CP E. coli.

Frequent carriage of resistance mechanisms to β-lactams and biofilm formation in Haemophilus influenzae causing treatment failure and recurrent otitis media in young children

OBJECTIVES

Non-typeable Haemophilus influenzae are a major cause of acute otitis media (AOM), including chronic and recurrent otitis in young children. The objective of this study was to determine whether non-typeable H. influenzae isolates causing these infections produce biofilms and carry resistance mechanisms to β-lactams.

METHODS

A collection of 48 H. influenzae isolates was obtained by tympanocentesis or from otorrhoea samples from individual patients <3 years of age and diagnosed with recurrent or treatment failure AOM. Each isolate was surveyed for the presence of blaTEM genes, amino acid substitutions in the transpeptidase domain of penicillin-binding protein 3 (PBP3) and biofilm formation in microtitre plates.

RESULTS

In 43 of the 48 isolates (89.6%), at least one of the three tested conditions was identified: biofilm formation (83.3%) and resistance mechanisms to β-lactams (33.3%), modifications in the transpeptidase domain of PBP3 being the most prevalent (22.9%), followed by β-lactamase production (10.4%). Additionally, 13 (27.1%) isolates had two or more of these three traits. In relation to biofilm formation, those isolates with an amoxicillin MIC ≤ 0.5 mg/L had higher optical density values than isolates with an amoxicillin MIC ≥ 1 mg/L (Mann-Whitney U-test, P=0.048).

CONCLUSIONS

These findings suggest that the successful treatment of non-typeable H. influenzae causing chronic and recurrent AOM in young children may be compromised by the high biofilm-forming capacity of the isolates and the presence of β-lactam resistance mechanisms, particularly PBP3 mutations.

Health care costs of complex perianal fistula in Crohn's disease

AIM

To evaluate the use of health care resources and the associated costs of complex perianal Crohn's disease (CD) from the National Health System perspective.

METHODS

We conducted a multicenter, retrospective, observational study in which gastroenterologists from 11 hospitals in the Community of Madrid took part. Data was collected on the direct healthcare resources (pharmacological treatments, surgical procedures, laboratory/diagnostic tests, visits to specialists and emergency departments, and hospitalizations) consumed by 97 adult patients with complex perianal CD which was active at some point between January 1, 2005, and case history review.

RESULTS

We recorded 527 treatments: 73.1% pharmacological (32.3% antibiotic, 20.5% immunomodulator, 20.3% biological) and 26.9% surgical. Mean annual global cost was €8,289/patient, 75.3% (€6,242) of which was accounted for by pharmacological treatments (€13.44 antibiotics; €1,136 immunomodulators; €5,093 biological agents), 12.4% (€1,027) by hospitalizations and surgery, 7.7% (€640) by medical visits, 4.2% (€350) by laboratory/diagnostic tests, and 0.4% (€30) by emergency department visits.

CONCLUSIONS

Pharmacological therapies, and in particular biological agents, are the main cost driver in complex perianal CD; costs due to surgery and hospitalizations are much lower.

Prevalence and molecular epidemiology of acquired AmpC β-lactamases and carbapenemases in Enterobacteriaceae isolates from 35 hospitals in Spain

The purpose of this investigation was to determine the prevalence of plasmid-mediated AmpC (pAmpC) and carbapenemases in Enterobacteriaceae collected from 35 hospitals in Spain and to establish their epidemiological relationships. We conducted a prospective multi-centre study on pAmpC- or carbapenemase-producing Enterobacteriaceae isolates from clinical samples collected from February to July 2009. The strains suspected to carry pAmpC were resistant or showed intermediate susceptibility to co-amoxiclav and second- or third-generation cephalosporins. Strains suspected to carry a carbapenemase were selected because they showed a minimum inhibitory concentration (MIC) to imipenem >1 mg/L. Polymerase chain reaction (PCR) and a sequencing strategy were used to characterise the enzymes. The clonal relationships between isolates was analysed by pulsed field gel electrophoresis (PFGE). Among 100,132 Enterobacteriaceae isolates collected, 1,654 were compatible with the production of pAmpC or carbapenemases. We found a prevalence of 0.64 % of pAmpC (n = 635) and 0.04 % of carbapenemases (n = 43). The most prevalent pAmpC enzymes were CMY-type (78.3 %), DHA-type (19.5 %), ACC-type (1.6 %) and FOX-type (0.6 %). The CMY-type was the most frequent in Escherichia coli and Proteus mirabilis species, whereas the DHA-type was mainly found in Klebsiella spp. The enzymes involved in carbapenem resistance were VIM-1, IMP-22 and the new IMP-28. Nine new bla genes were described: bla (CMY-54), bla (CMY-55), bla (CMY-56), bla (CMY-57), bla (CMY-96), bla (DHA-6), bla (DHA-7), bla (FOX-8) and bla (IMP-28). The prevalence of pAmpC or carbapenemases found is not negligible. The CMY-types were the predominant pAmpC, whereas the VIM or IMP enzymes were the predominant carbapenemases. Furthermore, we observed a great genetic diversity among pAmpC-producing strains and a close clonal relationship between carbapenemase-producing strains.

Parallel increase in community use of fosfomycin and resistance to fosfomycin in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli

OBJECTIVES

To document fosfomycin susceptibility of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC), analyse trends in fosfomycin use and investigate fosfomycin resistance in ESBL-EC isolated from urinary tract infections (UTIs).

METHODS

Twenty-seven Spanish hospitals participating in the European Antimicrobial Resistance Surveillance Network were requested to collect up to 10 sequential ESBL-EC for centralized susceptibility testing and typing. EUCAST guidelines were followed for antibiotic susceptibility testing, and bla(ESBL) type, phylogroups and O25b serotype were determined by PCR and sequencing. In addition, the trend in fosfomycin resistance among ESBL-EC causing UTIs was determined in 9 of the 27 hospitals. Total fosfomycin use for ambulatory care was established by WHO-recommended methods.

RESULTS

A total of 231 ESBL-EC (42.4% CTX-M-15, 34.2% SHV-12 and 23.4% CTX-M-14) were collected. The overall rate of fosfomycin resistance was 9.1%, but varied according to ESBL type (5.6% of CTX-M-14 isolates, 5.1% of SHV-12 and 15.3% of CTX-M-15). Of 67 O25b/B2 isolates, 11 (16.4%) were fosfomycin resistant. Predictors of infection with fosfomycin-resistant ESBL-EC were O25b/phylogroup B2 isolates, female gender and nursing home residence. Among 114 197 UTIs caused by E. coli 4740 (4.2%) were due to ESBL-EC. Fosfomycin resistance increased in these isolates from 4.4% (2005) to 11.4% (2009). The use of fosfomycin grew from 0.05 defined daily doses per 1000 inhabitants per day (1997) to 0.22 (2008), a 340% increase.

CONCLUSIONS

Key factors related to increased fosfomycin resistance in ESBL-EC causing UTIs could be the rapid growth in community use of fosfomycin, the widespread distribution of the 025b/B2 E. coli clone and the existence of a susceptible population comprising women residing in nursing home facilities.

Paroxetine-induced increase in LDL cholesterol levels

Paroxetine is widely prescribed because it has the indication for multiple psychiatric disorders. Our objective was to assess the effect of short-term administration of paroxetine on low-density lipoprotein cholesterol (LDL-C) levels in both healthy controls (HCs) and in patients with panic disorder (PD). Blood samples for measurement of LDL-C were collected atbaseline, after 8 weeks of paroxetine administration and post-discontinuation in 24 male HCs and nine male patients suffering from PD, for a total of 33 subjects. Paroxetine treatment, both in HCs and PD patients, induced a mean 9% increase per subject in LDL-C that normalized post-discontinuation, suggesting causality. The National Cholesterol Education Program (NCEP) guidelines suggest that this paroxetine-induced increase in LDL-C is clinically significant but would not warrant therapeutic intervention in this population selected to be at low cardiovascular risk. However, the increase in LDL-C levels raised above the threshold of 2.7 mmol/L (100 mg/dL) in 36% of our low-risk subjects. The LDL-C increase in this subgroup would be associated with a minor increase in coronary heart disease (CHD) risk. A similar 9% paroxetine-induced increase in LDL-C observed in the large number of psychiatric patients suffering from comorbid established CHD would be detrimental from a cardiovascular perspective and would oppose the new NCEP therapeutic goals of decreasing LDL-C levels by 30-40% in high and moderately high-risk patients. It is possible that longer treatment duration and use of higher doses of paroxetine would lead to a greater increase in LDL-C.

[Partial occipital seizures as main symptom of posterior encephalopathy secondary to immunosuppresants]

INTRODUCTION

Reversible posterior leukoencephalopathy syndrome (RPLS) affects patients who are following immunosupressive treatment. It can affect children too, it can be irreversible and occipital seizures can be the main manifestation. We describe the EEG of five children who presented occipital seizures due to posterior leukoencephalopathy syndrome secondary to treatment with immunosupressives. They had different clinico- electrical evolutions.

CASES REPORTS

Five children aged from 18 months to 11 years who had been treated with bone marrow, liver or kidney transplantation and one or two immunosupressive drugs: cyclosporine, tacrolimus. 4-50 days after the transplantation they presented arterial hypertension and low conscience. Occipital seizures or status were registered in EEG. Neuroimaging showed edema lesions in posterior regions. They were treated with antihipertensives, antiepileptics and substitution or reduction of immunosupressive drugs doses. Two patients presented further episodes and three of them had persistent abnormal EEG. Two patients had more than one status even though Cys A had been replaced by Tacrolimus or because the drug dose had not been modified. The Immunosupressive drugs are necessary for the transplantation's good outcome and they cannot be easily stopped.

CONCLUSIONS

Low conscience level and oculoclonic movements may form part of the subtle clinic of the occipital seizures, that may be the main manifestation of PLS in children who are following immunosupressor treatment. The realization of an EEG is indispensable for a quick diagnose and in order to achieve the reversibility of the syndrome. If we cannot get it, EEG will be useful for the evolution follow-up too.

[Quality of life and social functioning in schizophrenic patients treated with olanzapine: 1 year follow-up naturalistic study]

OBJECTIVE

To measure health related quality of life (HRQL) and social functioning in schizophrenic patients treated with olanzapine under regular clinical practice conditions.

METHODS

Out-patients diagnosed of schizophrenia and beginning treatment with olanzapine, quetiapine, risperidone or typical oral antipsychotics were included. Information on socio-demographic characteristics was obtained and in each visit (baseline, 3, 6 and 12 months) they were administered the generic HRQL questionnaire Euro-QoL-5D (EQ-5D) and the Social Functioning Scale (SFS).

RESULTS

A total of 1,198 patients were followed-up for 12 months. Mean age (SD) was 38.6 (13.3) years and 62.9 % of them were men. In basal conditions the most affected dimensions of EQ-5D were anxiety/depression (76 %), and daily activities (73.6 %). After 12 months treatment the cohort of patients treated with olanzapine showed a better HRQL in the self-care dimension compared to all other treatments (p < 0.05), and in the dimensions of pain/discomfort, anxiety/depression and usual activities compared to the group treated with quetiapine and risperidone (p < 0.05). The Visual Analogue Scale (VAS) of the EQ-5D questionnaire showed a better health state after 12 months in the group treated with olanzapine compared to the groups of quetiapine or risperidone (p < 0.05). The SFS showed a better improvement in the cohort of olanzapine in the three studied dimensions after 12 months: isolation and social relationships in comparison to the risperidone group (p < 0.05), interpersonal communication in comparison to the risperidone and quetiapine group (p < 0.05) and independence performance in comparison to all the other treatments (p < 0,05).

CONCLUSION

Schizophrenic patients treated with olanzapine for one year show a better improvement in HRQL and social functioning than those treated with other antipsychotics.

Expression of angiogenesis factors in human umbilical vein endothelial cells and their regulation by PEDF

The VEGFs and FGF-2 stimulate angiogenesis. Pigment epithelium-derived factor (PEDF) and thrombospondin-1 (TSP-1) strongly inhibit angiogenesis. Human umbilical vein endothelial cells (HUVECs) expressed VEGF-A, -B, -C, the VEGF receptors R1, R2, and R3, PEDF, FGF-2, and TSP-1, but VEGF-D transcripts were barely detectable. Hypoxia reduced the transcript levels of VEGF-C and its cognate receptor, VEGF-R3. PEDF blocked the effect of CoCl(2) on these two factors. The expression of VEGF-A and -B as well as VEGF-R1 and VEGF-R2 remained unchanged after exposure to hypoxia, PEDF, or both. There was a marked reduction in TSP-1 transcripts in CoCl(2) treated cultures and PEDF blocked this reduction. PEDF induced a small increase in FGF-2 transcripts in HUVECs, but there was no change in FGF-2 expression in HUVECs exposed to hypoxia or hypoxia plus PEDF. PEDF may control neovascularization, in part, by restoring the negative effects of hypoxia on the expression of a potent angiogenesis inhibitor, TSP-1. PEDF may also modulate vascular leakage by maintaining the transcriptional levels of the vascular homeostasis factors, VEGF-C and VEGF-R3 in hypoxic conditions.

Regulation of factors controlling angiogenesis in liver development: a role for PEDF in the formation and maintenance of normal vasculature

PEDF and VEGF are important inhibitors and promoters of angiogenesis, and the ratio between the two is an important indicator in many neovascular diseases. In mouse liver PEDF and VEGF(165) were co-expressed at very early stages of liver development and their expression increased as liver embryogenesis progressed, suggesting that PEDF and VEGF are both crucial to vasculogenesis as well. VEGF(189) only appears at the P0 stage in liver organogenesis and is maintained at high levels thereafter. PEDF and the two VEGF isoforms are synthesized by fresh and cultured hepatocytes. Expression of VEGF(121) and overexpression of VEGF(165) were only seen in HepG2, a well-characterized hepatocellular carcinoma line. The results suggest that hepatic vascular architecture is under the control of both PEDF and VEGF, and that VEGF(165) and VEGF(189) have distinct functions in normal vascular development of the liver. The VEGF isoforms 121 and 189 may be key regulators of increased vascularity and progression of hepatocellular carcinoma, one of the most common malignant tumors, and may be of prognostic significance for this tumor.

Retinoic acid and dexamethasone regulate the expression of PEDF in retinal and endothelial cells

Both all-trans-retinoic acid (ATRA) and pigment epithelial-derived factor (PEDF) regulate cell proliferation and differentiation. Treatment of human Y-79 retinoblastoma and A-RPE 19 pigment epithelial cells with ATRA increased the levels of PEDF protein and RNA. Endothelial cells from bovine retina and human umbilical cord expressed PEDF and the levels were also increased by ATRA. Mouse Müller glial cells and rat C6 glioma cells showed at least a 2.5 fold increase in PEDF RNA levels after ATRA treatment, as measured by quantitative PCR. The PEDF promoter contains a retinoic acid receptor element (RARE). Plasmids containing a PEDF promoter regulating a luciferase gene were transfected into D407 and C6 cells and the luciferase activity measured after incubation in the presence or absence of ATRA. In both cell types ATRA increased the level of luciferase activity suggesting the RARE is functional. Dexamethasone was also effective at increasing PEDF RNA levels in both mouse Muller glial cells and C6 rat glioma cells. To test the effects of PEDF on retinoic acid function, expression of retinoic acid receptors in Y-79 and A-RPE 19 cells was measured by PCR. In Y79 cells, PEDF treatment increased the expression levels of RARalpha and RXRgamma receptors and in the A-RPE 19 cells it resulted in a decrease in expression of the RARbeta and RXRbeta receptors. This study clearly indicates an interaction between PEDF and ATRA. The cell differentiation activities of PEDF may operate through mechanisms orchestrated by retinoids, and the converse may also be true. The differentiation, anti-mitotic, and apoptotic actions of PEDF and ATRA may utilize parallel pathways that converge at key junctional transduction molecules to coordinate cellular quiescence and maintain tissue mass in the presence of signals that stimulate abnormal cell proliferation. It will be an interesting therapeutic strategy to co-administer PEDF and retinoic acid in developing protocols for neovascular diseases in the eye and in cancer.

Current status of treatment completion and fatality among tuberculosis patients in Spain

OBJECTIVES

To determine treatment completion among patients with tuberculosis (TB), and to analyse factors associated with treatment default and fatality.

METHODS

A prospective cohort study of patients who began treatment between 1 June 1999 and 31 May 2000 in areas where members of the SEPAR Tuberculosis and Respiratory Infections Group work. Factors associated with treatment default and fatality were studied using logistic regression, calculating odds ratios (OR) and their 95% confidence intervals (95%CI).

RESULTS

The study involved 142 physicians from 76 different hospitals who provided information on 1515 cases. Eighty-two per cent of the patients completed treatment correctly, 14% defaulted, 5% died, 0.5% failed, and 8.7% interrupted treatment due to transfer or other reasons. The variables associated with default were intravenous drug use (IVDU) (OR 6.00, 95%CI 2.59-13.89) and immigration (OR 8.57, 95%CI 3.78-19.45); sex, age, homelessness, incarceration, directly observed treatment (DOT) or hospitalisation were not associated with default. Variables found to be predictive of fatality were alcoholism (OR 6.38, 95%CI 2.09-19.48), human immunodeficiency virus (HIV) infection (OR 7.08, 95%CI 2.08-29.15) and age >64 years (OR 10, 95%CI 2.9-34.07), whereas sex, IVDU, homelessness, DOT and hospitalisation were not.

CONCLUSIONS

In industrialised countries, IVDU patients and immigrants should be targeted for DOT, while to reduce fatality rates stricter monitoring is required for patients who are alcoholic, HIV-infected, or aged >64 years.

Evaluation of tuberculosis trends in Spain, 1991-1999

SETTING

There are no reliable official data available on tuberculosis (TB) in Spain.

OBJECTIVE

To ascertain the epidemiological trends of TB in Spain from 1991-1999.

METHODS

In an annual survey conducted by the Tuberculosis and Respiratory Infections (TRI) Working Group of the Spanish Society of Pneumology and Thoracic Surgery (SEPAR), data on tuberculosis disease and infection were solicited from two information sources: 1) the public health services of the 17 Autonomous Regions (AR), and 2) 60 TRI members in different parts of Spain.

RESULTS

TB incidence declined from 36.4/100,000 in 1991 to 26.7 in 1999 according to the AR (average annual decline 3.3%), and from 45.6 to 26.8 according to TRI members (annual decline 5.1%). A similar observation was made for smear-positive cases (AR annual decline: 3.0%; TRI: 5.6%). Tuberculosis infection at 6 years of age also decreased according to both information sources (AR: 0.87% in 1991 to 0.5% in 1998, annual decline 6%, and TRI members: 1.00% in 1991 and 0.9% in 1997, annual decline 4.2%).

CONCLUSIONS

The observed rates of TB are higher than stated in official figures. In spite of the decreasing trend, observed declines are small and the current rates continue to be among the highest among industrialised countries.

Effect of medroxyprogesterone pretreatment on pentagastrin-induced panic symptoms in females with panic disorder

Clinical observation, as well as epidemiological and research data, suggest that female gonadal hormones influence the course of panic disorder (PD). Panicogenic agents such as pentagastrin are useful tools with which to study the pathophysiology of panic attacks. Nine women with PD were randomly assigned to receive, in a crossover design, a 3-day pretreatment with medroxyprogesterone acetate (MP) prior to an injection of pentagastrin, and a 3-day pretreatment with a placebo prior to another injection of pentagastrin. The panic response and the anxiety response to pentagastrin were decreased after MP pretreatment. These preliminary results support the use of laboratory models for investigations of the interactions between progestins and anxiety.

Simultaneous determination of ascorbic acid and acetylsalicylic acid in pharmaceutical formulations

A direct, simple, and practical first-derivative spectrophotometric method is described for simultaneous determination of ascorbic acid and acetylsalicylic acid. The effects of the solvent, excipients, and spectral variables on the analytical signal were investigated. The drugs were determined simultaneously with a 0.01 M methanolic hydrochloric acid solution as the solvent, and the signals were evaluated directly by using the zero-crossing method at 245.0 and 256.0 nm for acetylsalicylic acid and ascorbic acid, respectively. The method allows the simultaneous determinations of acetylsalicylic acid and ascorbic acid in the ranges of 6.6 x 10(-6) to 1.5 x 10(-4)M and 3.4 x 10(-6) to 2.0 x 10(-4)M, respectively, with standard deviation of <2.0%. The proposed method was applied to determinations of these drugs in tablets.

Simultaneous determination of chlordiazepoxide and clidinium bromide in pharmaceutical formulations by derivative spectrophotometry

A direct and simple first derivative spectrophotometric method has been developed for the simultaneous determination of clidinium bromide and chlordiazepoxide in pharmaceutical formulations. Acetonitrile was used as solvent for extracting the drugs from the formulations and subsequently the samples were evaluated directly by derivative spectrophotometry. Simultaneous determination of the drugs can be carried out using the zero-crossing method for clidinium bromide at 220.8 nm and the graphical method for chlordiazepoxide at 283.6 nm. The calibration graphs were linear in the ranges from 0.983 to 21.62 mg/l of clidinium bromide and from 0. 740 to 12.0 mg/l of chlordiazepoxide. The ingredients commonly found in commercial pharmaceutical formulations do not interfere. The proposed method was applied to the determination of these drugs in tablets.