Evolution of invasive pneumococcal disease by serotype 3 in adults: a Spanish three-decade retrospective study

Background

Invasive pneumococcal disease due to serotype 3 (S3-IPD) is associated with high mortality rates and long-term adverse effects. The introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) into the Spanish paediatric immunisation programme has not led to a decrease in the adult S3-IPD. We aimed to analyse the incidence, clinical characteristics and genomics of S3-IPD in adults in Spain.

Methods

Adult IPD episodes hospitalized in a Southern Barcelona hospital were prospectively collected (1994-2020). For genomic comparison, S3-IPD isolates from six Spanish hospitals (2008-2020) and historical isolates (1989-1993) were analysed by WGS (Illumina and/or MinION).

Findings

From 1994 to 2020, 270 S3-IPD episodes were detected. When comparing pre-PCV (1994-2001) and late-PCV13 (2016-2020) periods, only modest changes in S3-IPD were observed (from 1.58 to 1.28 episodes per 100,000 inhabitants year). In this period, the incidence of the two main lineages shifted from 0.38 to 0.67 (CC180-GPSC12) and from 1.18 to 0.55 (CC260-GPSC83). The overall 30-day mortality remained high (24.1%), though a decrease was observed between the pre-PCV (32.4%; 95.0% CI, 22.0-45.0) and the late-PCV13 period (16.7%; 95.0% CI, 7.5-32.0) (p = 0.06). At the same time, comorbidities increased from 77.3% (95.0% CI, 65.0-86.0) to 85.7% (95.0% CI, 71.0-94.0) (p = 0.69). There were no differences in clinical characteristics or 30-day mortality between the two S3 lineages. Although both lineages were genetically homogeneous, the CC180-GPSC12 lineage presented a higher SNP density, a more open pan-genome, and a major presence of prophages and mobile genetic elements carrying resistance genes.

Interpretation

Adult S3-IPD remained stable in our area over the study period despite PCV13 introduction in children. However, a clonal shift was observed. The decrease in mortality rates and the increase in comorbidities suggest a change in clinical management and overall population characteristics. The low genetic variability and absence of clinical differences between lineages highlight the role of the S3 capsule in the disease severity.

Funding

This study has been funded by Instituto de Salud Carlos III (ISCIII) "PI18/00339", "PI21/01000", "INT22/00096", "FI22/00279", CIBER "CIBERES-CB06/06/0037", "CIBERINFEC-CB21/13/00009" and MSD grant "IISP 60168".

Imipenem heteroresistance but not tolerance in Haemophilus influenzae during chronic lung infection associated with chronic obstructive pulmonary disease

Antibiotic resistance is a major Public Health challenge worldwide. Mechanisms other than resistance are described as contributors to therapeutic failure. These include heteroresistance and tolerance, which escape the standardized procedures used for antibiotic treatment decision-making as they do not involve changes in minimal inhibitory concentration (MIC). Haemophilus influenzae causes chronic respiratory infection and is associated with exacerbations suffered by chronic obstructive pulmonary disease (COPD) patients. Although resistance to imipenem is rare in this bacterial species, heteroresistance has been reported, and antibiotic tolerance cannot be excluded. Moreover, development of antibiotic heteroresistance or tolerance during within-host H. influenzae pathoadaptive evolution is currently unknown. In this study, we assessed imipenem resistance, heteroresistance and tolerance in a previously sequenced longitudinal collection of H. influenzae COPD respiratory isolates. The use of Etest, disc diffusion, population analysis profiling, tolerance disc (TD)-test methods, and susceptibility breakpoint criteria when available, showed a significant proportion of imipenem heteroresistance with differences in terms of degree among strains, absence of imipenem tolerance, and no specific trends among serial and clonally related strains could be established. Analysis of allelic variation in the ftsI, acrA, acrB, and acrR genes rendered a panel of polymorphisms only found in heteroresistant strains, but gene expression and genome-wide analyses did not show clear genetic traits linked to heteroresistance. In summary, a significant proportion of imipenem heteroresistance was observed among H. influenzae strains isolated from COPD respiratory samples over time. These data should be useful for making more accurate clinical recommendations to COPD patients.

Detection of blaCTX-M-15 in an integrative and conjugative element in four extensively drug-resistant Haemophilus parainfluenzae strains causing urethritis

Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in urogenital infection. The aim of this work was to identify and characterise the molecular mechanisms of resistance associated with four cephalosporin-resistant H. parainfluenzae strains collected from patients with urethritis. Antimicrobial resistance was determined by microdilution following European Committee on Antimicrobial Susceptibility Testing criteria. Strains were then analysed by whole-genome sequencing to determine clonal relationship and the molecular basis of antimicrobial resistance. Finally, a phylogenetic analysis was performed on all urogenital MDR strains of H. parainfluenzae previously isolated in our hospital. All strains were resistant to β-lactams, macrolides, tetracycline, fluoroquinolones, chloramphenicol, cotrimoxazole, and aminoglycosides. The resistance profile was compatible with the presence of an extended-spectrum β-lactamase (ESBL). Whole-genome sequencing detected blaCTX-M-15 that conferred high minimum inhibitory concentrations to cephalosporins in two novel integrative and conjugative elements (ICEHpaHUB6 and ICEHpaHUB7) that also harboured a blaTEM-1 β-lactamase. This study shows a novel blaCTX-M-15 ESBL carried in an integrative conjugative element in four extensively drug-resistant H. parainfluenzae strains. This resistance determinant could be transmitted to other sexually transmitted pathogens and this is a cause for concern.

Genetic Adaptation and Acquisition of Macrolide Resistance in Haemophilus spp. during Persistent Respiratory Tract Colonization in Chronic Obstructive Pulmonary Disease (COPD) Patients Receiving Long-Term Azithromycin Treatment

Patients with chronic obstructive pulmonary disease (COPD) benefit from the immunomodulatory effect of azithromycin, but long-term administration may alter colonizing bacteria. Our goal was to identify changes in Haemophilus influenzae and Haemophilus parainfluenzae during azithromycin treatment. Fifteen patients were followed while receiving prolonged azithromycin treatment (Hospital Universitari de Bellvitge, Spain). Four patients (P02, P08, P11, and P13) were persistently colonized by H. influenzae for at least 3 months and two (P04 and P11) by H. parainfluenzae. Isolates from these patients (53 H. influenzae and 18 H. parainfluenzae) were included to identify, by whole-genome sequencing, antimicrobial resistance changes and genetic variation accumulated during persistent colonization. All persistent lineages isolated before treatment were azithromycin-susceptible but developed resistance within the first months, apart from those belonging to P02, who discontinued the treatment. H. influenzae isolates from P08-ST107 acquired mutations in 23S rRNA, and those from P11-ST2480 and P13-ST165 had changes in L4 and L22. In H. parainfluenzae, P04 persistent isolates acquired changes in rlmC, and P11 carried genes encoding MefE/MsrD efflux pumps in an integrative conjugative element, which was also identified in H. influenzae P11-ST147. Other genetic variation occurred in genes associated with cell wall and inorganic ion metabolism. Persistent H. influenzae strains all showed changes in licA and hgpB genes. Other genes (lex1, lic3A, hgpC, and fadL) had variation in multiple lineages. Furthermore, persistent strains showed loss, acquisition, or genetic changes in prophage-associated regions. Long-term azithromycin therapy results in macrolide resistance, as well as genetic changes that likely favor bacterial adaptation during persistent respiratory colonization. IMPORTANCE The immunomodulatory properties of azithromycin reduce the frequency of exacerbations and improve the quality of life of COPD patients. However, long-term administration may alter the respiratory microbiota, such as Haemophilus influenzae, an opportunistic respiratory colonizing bacteria that play an important role in exacerbations. This study contributes to a better understanding of COPD progression by characterizing the clinical evolution of H. influenzae in a cohort of patients with prolonged azithromycin treatment. The emergence of macrolide resistance during the first months, combined with the role of Haemophilus parainfluenzae as a reservoir and source of resistance dissemination, is a cause for concern that may lead to therapeutic failure. Furthermore, genetic variations in cell wall and inorganic ion metabolism coding genes likely favor bacterial adaptation to host selective pressures. Therefore, the bacterial pathoadaptive evolution in these severe COPD patients raise our awareness of the possible spread of macrolide resistance and selection of host-adapted clones.

An Overview of Macrolide Resistance in Streptococci: Prevalence, Mobile Elements and Dynamics

Streptococcal infections are usually treated with beta-lactam antibiotics, but, in case of allergic patients or reduced antibiotic susceptibility, macrolides and fluoroquinolones are the main alternatives. This work focuses on studying macrolide resistance rates, genetic associated determinants and antibiotic consumption data in Spain, Europe and also on a global scale. Macrolide resistance (MR) determinants, such as ribosomal methylases (erm(B), erm(TR), erm(T)) or active antibiotic efflux pumps and ribosomal protectors (mef(A/E)-mrs(D)), are differently distributed worldwide and associated with different clonal lineages and mobile genetic elements. MR rates vary together depending on clonal dynamics and on antibiotic consumption applying selective pressure. Among Streptococcus, higher MR rates are found in the viridans group, Streptococcus pneumoniae and Streptococcus agalactiae, and lower MR rates are described in Streptococcus pyogenes. When considering different geographic areas, higher resistance rates are usually found in East-Asian countries and milder or lower in the US and Europe. Unfortunately, the availability of data varies also between countries; it is scarce in low- and middle- income countries from Africa and South America. Thus, surveillance studies of macrolide resistance rates and the resistance determinants involved should be promoted to complete global knowledge among macrolide resistance dynamics.

Analysis of patient outcomes after urological surgery during the second and third waves of SARS-CoV-2 pandemic in a high incidence area

OBJECTIVE

To analyze surgical safety through postoperative COVID-19 incidence and mortality at the urology department of a tertiary hospital located in Madrid (Spain).

METHODS

Observational, prospective study including all patients undergoing urological surgery from 1st March 2020 to 28th February 2021. According to the hospital organization and local epidemiological situation we delimitate three epidemic waves. A set of screening and protective measures was applied from 4th May onwards. Demographic, baseline, surgical and perioperative variables, as well as postoperative outcomes, were collected. Telephone follow-up was performed at least 3 weeks after hospital discharge.

RESULTS

940 urological surgeries were performed, 12 of them had to be rescheduled due to active or recent SARS-CoV-2 infection identified by the screening protocol. Thirty-one patients developed COVID-19 (3.3% incidence) and 7 died (22.6% mortality). The average time to onset of symptoms was 62.6 days after discharge, being 25 cases attributable to community transmission. The remaining 6 cases, due to in-hospital transmission, had worse outcomes. Five of them were identified during the first wave, especially when no preoperative PCR was obtained. In contrast, during the second and third waves, fewer and milder cases were diagnosed, with just 1 in-hospital transmission among 857 urological patients.

CONCLUSIONS

After implementing complete protective measures, postoperative in-hospital COVID-19 cases almost disappeared, even during the second and third waves. Most of the cases were due to community transmission and thus driven by the general epidemiological situation. While hospitals follow recommendations to avoid COVID-19 infection, urological surgery remains safe and can be maintained.

Genomic features of predominant non-PCV13 serotypes responsible for adult invasive pneumococcal disease in Spain

BACKGROUND

Although pneumococcal conjugate vaccines (PCVs) effectively prevent invasive pneumococcal disease (IPD), serotype replacement has occurred.

OBJECTIVES

We studied the pangenome, antibiotic resistance mechanisms and presence of mobile elements in predominant non-PCV13 serotypes causing adult IPD after PCV13 vaccine introduction in Spain.

METHODS

We conducted a multicentre study comparing three periods in six Spanish hospitals and analysed through whole genome sequencing representative strains collected in the pre-PCV13, early-PCV13 and late-PCV13 periods.

RESULTS

Among 2197 cases of adult IPD identified, 110 pneumococci expressing non-PCV13 capsules were sequenced. Seven predominant serotypes accounted for 42.6% of IPD episodes in the late-PCV13 period: serotypes 8 (14.4%), 12F (7.5%), 9N (5.2%), 11A (4.1%), 22F (3.9%), 24F (3.9%) and 16F (3.6%). All predominant non-PCV13 serotypes were highly clonal, comprising one or two clonal complexes (CC). In general, CC538, CC4048, CC3016F, CC43322F and CC669N, related to predominant non-PCV13 serotypes, were antibiotic susceptible. CC15611A was associated with resistance to co-trimoxazole, penicillin and amoxicillin. CC23024F was non-susceptible to penicillin and resistant to erythromycin, clindamycin, and tetracycline. Six composite transposon structures of the Tn5252-family were found in CC23024F, CC98912F and CC3016F carrying different combinations of erm(B), tet(M), and cat. Pangenome analysis revealed differences in accessory genomes among the different CC, with most variety in CC3016F (23.9%) and more conservation in CC15611A (8.5%).

CONCLUSIONS

We identified highly clonal predominant serotypes responsible for IPD in adults. The detection of not only conjugative elements carrying resistance determinants but also clones previously associated with vaccine serotypes (CC15611A and CC23024F) highlights the importance of the accessory genome.

SARS-CoV-2 outbreak in a nursing home after vaccination with BNT162b2: A role for the quantification of circulating antibodies

We describe an outbreak of SARS-CoV-2 (B.1.351) in a nursing home. At the outbreak onset 96% of residents and 76% of HCW had received two doses of BNT162b2. Twenty-eight residents (28/53) and six HCW (6/33) were infected. Infected residents had lower levels of anti-S antibodies compared to those who were not infected (157 vs 552 U/mL). Among 50 residents with available serological status, nineteen (19/25) with serum concentration < 300 U/mL and seven (7/25) with concentration > 300 U/mL acquired SARS-CoV-2 (RR 2.7 [95 %CI 1.4–5.3]). The quantification of circulating antibodies could be useful in detecting people with an impaired immune response who are at high risk of acquiring and spreading SARS-CoV-2.

Epidemiology and population structure of Haemophilus influenzae causing invasive disease

This study provides an update on invasive Haemophilus influenzae disease in Bellvitge University Hospital (2014–2019), reporting its evolution from a previous period (2008–2013) and analysing the non-typeable H. influenzae (NTHi) population structure using a clade-related classification. Clinical data, antimicrobial susceptibility and serotyping were studied and compared with those of the previous period. Population structure was assessed by multilocus sequence typing (MLST), SNP-based phylogenetic analysis and clade-related classification. The incidence of invasive H. influenzae disease remained constant between the two periods (average 2.07 cases per 100 000 population), while the 30 day mortality rate decreased (20.7–14.7 %, respectively). Immunosuppressive therapy (40 %) and malignancy (36 %) were the most frequent comorbidities. Ampicillin and fluoroquinolone resistance rates had increased between the two periods (10–17.6 % and 0–4.4 %, respectively). NTHi was the main cause of invasive disease in both periods (84.3 and 85.3 %), followed by serotype f (12.9 and 8.8 %). NTHi displayed high genetic diversity. However, two clusters of 13 (n=20) and 5 sequence types (STs) (n=10) associated with clade V included NTHi strains of the most prevalent STs (ST3 and ST103), many of which showed increased frequency over time. Moreover, ST103 and ST160 from clade V were associated with β-lactam resistance. Invasive H. influenzae disease is uncommon, but can be severe, especially in the elderly with comorbidities. NTHi remains the main cause of invasive disease, with ST103 and ST160 (clade V) responsible for increasing β-lactam resistance over time.

Deciphering mobile genetic elements disseminating macrolide resistance in Streptococcus pyogenes over a 21 year period in Barcelona, Spain

OBJECTIVES

To phenotypically and genetically characterize the antibiotic resistance determinants and associated mobile genetic elements (MGEs) among macrolide-resistant (MR) Streptococcus pyogenes [Group A streptococci (GAS)] clinical isolates collected in Barcelona, Spain.

METHODS

Antibiotic susceptibility testing was performed by microdilution. Isolates were emm and MLST typed and 55 were whole-genome sequenced to determine the nature of the macrolide resistance (MR) determinants and their larger MGE and chromosomal context.

RESULTS

Between 1998 and 2018, 142 of 1028 GAS (13.8%) were MR. Among 108 isolates available for molecular characterization, 41.7% had cMLSB, 30.5% iMLSB and 27.8% M phenotype. Eight erm(B)-containing strains were notable in having an MDR phenotype conferred by an MGE encoding several antibiotic resistance genes. MR isolates were comprised of several distinct genetic lineages as defined by the combination of emm and ST. Although most lineages were only transiently present, the emm11/ST403 clone persisted throughout the period. Two lineages, emm9/ST75 with erm(B) and emm77/ST63 with erm(TR), emerged in 2016-18. The erm(B) was predominantly encoded on the Tn916 family of transposons (21/31) with different genetic contexts, and in other MGEs (Tn6263, ICESpHKU372 and one harbouring an MDR cluster called ICESp1070HUB). The erm(TR) was found in ICESp2905 (8/17), ICESp1108-like (4/17), ICESpHKU165 (3/17) and two structures described in this study (IMESp316HUB and ICESp3729HUB). The M phenotype [mef(A)-msr(D)] was linked to phage φ1207.3. Eight integrative conjugative element/integrative mobilizable element (ICE/IME) cluster groups were classified on the basis of gene content within conjugation modules. These groups were found among MGEs, which corresponded with the MR-containing element or the site of integration.

CONCLUSIONS

We detected several different MGEs harbouring erm(B) or erm(TR). This is the first known description of Tn6263 in GAS and three MGEs [IMESp316HUB, ICESp3729HUB and ICESp1070HUB] associated with MR. Periods of high MR rates in our area were mainly associated with the expansion of certain predominant lineages, while in low MR periods different sporadic and low prevalence lineages were more frequent.

Genome-wide analysis of urogenital and respiratory multidrug-resistant Haemophilus parainfluenzae

OBJECTIVES

To characterize the mechanisms of antimicrobial resistance and the prevalence of the polysaccharide capsule among urogenital and respiratory Haemophilus parainfluenzae isolates.

METHODS

Antimicrobial susceptibility was tested by microdilution. Fifty-five MDR strains were subjected to WGS and were phylogenetically compared with all the available H. parainfluenzae genomes from the NCBI database. The identification of the capsular bexA gene was performed by PCR in 266 non-MDR strains.

RESULTS

In 31 of the 42 ampicillin-resistant strains, blaTEM-1 located within Tn3 was identified. β-Lactamase-negative cefuroxime-resistant strains (n = 12) presented PBP3 substitutions. The catS gene (n = 14), the tet(M)-MEGA element (n = 18) and FolA substitutions (I95L and F154V/S) (n = 41) were associated with resistance to chloramphenicol, tetracycline plus macrolides, and co-trimoxazole, respectively. Thirty-seven isolates had a Tn10 harbouring tet(B)/(C)/(D)/(R) genes with (n = 15) or without (n = 22) catA2. Putative transposons (Tn7076-Tn7079), including aminoglycoside and co-trimoxazole resistance genes, were identified in 10 strains (18.2%). These transposons were integrated into three new integrative and conjugative elements (ICEs), which also included the resistance-associated transposons Tn3 and Tn10. The capsular operon was found only in the urogenital isolates (18/154, 11.7%), but no phylogenetic clustering was observed. The capsular operons identified were similar to those of Haemophilus influenzae serotype c and Haemophilus sputorum type 2.

CONCLUSIONS

The identification of ICEs with up to three resistance-associated transposons suggests that these transferable elements play an important role in the acquisition of multidrug resistance in H. parainfluenzae. Moreover, the presence of polysaccharide capsules in some of these urogenital isolates is a cause for concern.

A historical perspective of MDR invasive pneumococcal disease in Spanish adults

OBJECTIVES

To analyse the clonal dynamics and clinical characteristics of adult invasive pneumococcal disease (IPD) caused by MDR and penicillin-non-susceptible (PNS) pneumococci in Spain.

METHODS

All adult IPD episodes were prospectively collected (1994-2018). Streptococcus pneumoniae isolates were serotyped, genotyped and tested for antimicrobial susceptibility. Changes in the incidence of IPD were analysed and risk factors contributing to MDR were assessed by logistic regression.

RESULTS

Of 2095 IPD episodes, 635 (30.3%) were caused by MDR/PNS isolates. Over the study period, the incidence of MDR/PNS-IPD decreased (IRR 0.70; 95% CI 0.53-0.93) whereas that of susceptible isolates remained stable (IRR 0.96; 95% CI 0.80-1.16). A reduction of resistance rates to penicillin (-19.5%; 95% CI -37% to 2%) and cefotaxime (-44.5%; 95% CI -64% to -15%) was observed. Two clones, Spain9V-ST156 and Denmark14-ST230, accounted for 50% of current resistant disease. Among current MDR/PNS isolates, 45.8% expressed serotypes not covered by the upcoming PCV15/PCV20 vaccines. MDR/PNS episodes were associated with older patients with comorbidities, nosocomial acquisition and higher 30 day mortality. MDR/PNS pneumococci were not independently associated with 30 day mortality in multivariate analysis [OR 0.826 (0.648-1.054)].

CONCLUSIONS

Our study shows an overall reduction of MDR/PNS isolates in adults after the introduction of pneumococcal conjugate vaccines. However, a significant proportion of current resistant isolates are not covered by any of the upcoming PCV15/PCV20 vaccines. The burden of resistant disease is related to older patients with underlying conditions and caused by two major clones. Our data show that MDR is not a statistically significant factor related to increased mortality.

Evaluation of health care-associated infections following radical cystectomy

INTRODUCTION AND OBJECTIVE

Radical cystectomy is a complex surgery with a high rate of complications including infections, which lead to increased morbidity and mortality, longer hospital stay and higher costs. The aim of this work is to evaluate health care-associated infections (HAIs) in these patients, as well as associated microorganisms, antibiotic resistance profiles and risk factors.

MATERIAL AND METHODS

Prospective study from 2012 to 2017. Epidemiologic variables, comorbidities and surgical variables are collected. The microorganisms involved and antibiotic susceptibility patterns are analyzed.

RESULTS

122 patients. Mean age 67 (SD:18,42). Mean hospital stay 23.5 days (18.42). HAIs rate of 45%, with predominant urinary tract infections (43%) and surgical wound infections (31%). Positive cultures in 78.6% of cases. Increased isolation of Enterococcus (18%) and Escherichia coli (13%). Forty-three percent of microorganisms were resistant to amoxicillin/ampicillin, 23% to beta-lactamases and 36% to quinolones. Empirical treatment was adequate in 87.5%. Hospital stay is increased (17 days, p< 0.05) due to HAIs. Lower rate of infectious complications in the laparoscopic vs. open approach (p< 0.001) and in orthotopic vs. ileal conduit diversion (p = 0.04) CONCLUSIONS: We found a high rate of HAIs in our radical cystectomy series, with predominant urinary tract and surgical wound infections. E.coli and Enterococcus spp. are the most frequently isolated microorganisms, with high rates of resistance to some commonly used antibiotics.

Two multi-fragment recombination events resulted in the β-lactam-resistant serotype 11A-ST6521 related to Spain9V-ST156 pneumococcal clone spreading in south-western Europe, 2008 to 2016

BackgroundThe successful pneumococcal clone Spain9V-ST156 (PMEN3) is usually associated with vaccine serotypes 9V and 14.AimOur objective was to analyse the increase of a serotype 11A variant of PMEN3 as cause of invasive pneumococcal disease (IPD) in Spain and its spread in south-western Europe.MethodsWe conducted a prospective multicentre study of adult IPD in Spain (2008-16). Furthermore, a subset of 61 penicillin-resistant serotype 11A isolates from France, Italy, Portugal and Spain were subjected to whole genome sequencing (WGS) and compared with 238 genomes from the European Nucleotide Archive (ENA).ResultsAlthough the incidence of serotype 11A in IPD was stable, a clonal shift was detected from CC62 (penicillin-susceptible) to CC156 (penicillin-resistant). By WGS, three major 11A-CC156 lineages were identified, linked to ST156 (n = 5 isolates; France, Italy and Portugal), ST166 (n = 4 isolates; France and Portugal) and ST838/6521 (n = 52 isolates; France, Portugal and Spain). Acquisition of the 11A capsule allowed to escape vaccine effect. AP200 (11A-ST62) was the donor for ST156 and ST838/6521 but not for ST166. In-depth analysis of ST838/6521 lineage showed two multi-fragment recombination events including four and seven fragments from an 11A-ST62 and an NT-ST344 representative, respectively.ConclusionThe increase in penicillin-resistant serotype 11A IPD in Spain was linked to the spread of a vaccine escape PMEN3 recombinant clone. Several recombination events were observed in PMEN3 acquiring an 11A capsule. The most successful 11A-PMEN3 lineage spreading in south-western Europe appeared after two multi-fragment recombination events with representatives of two major pneumococcal clones (11A-ST62 and NT-ST344).

Urological surgery during SARS-CoV-2 pandemic. Descriptive analysis of the experience in a Urology Department across the pandemic phases

Introduction

Methods

Results

Conclusions

Host- and Pathogen-Related Factors for Acute Cardiac Events in Pneumococcal Pneumonia

Background

Acute cardiac events (ACEs) are increasingly being recognized as a major complication in pneumococcal community-acquired pneumonia (CAP). Information regarding host- and pathogen-related factors for ACEs, including pneumococcal serotypes and clonal complexes, is scarce.

Methods

A retrospective study was conducted of a prospective cohort of patients hospitalized for CAP between 1996 and 2019. Logistic regression and funnel plot analyses were performed to determine host- and pathogen-related factors for ACEs.

Results

Of 1739 episodes of pneumococcal CAP, 1 or more ACEs occurred in 304 (17.5%) patients, the most frequent being arrhythmia (n = 207), heart failure (n = 135), and myocardial infarction (n = 23). The majority of ACEs (73.4%) occurred within 48 hours of admission. Factors independently associated with ACEs were older age, preexisting heart conditions, pneumococcal bacteremia, septic shock at admission, and high-risk pneumonia. Among 983 pneumococcal isolates, 872 (88.7%) were serotyped and 742 (75.5%) genotyped. The funnel plot analyses did not find any statistically significant association between serotypes or clonal complexes with ACEs. Nevertheless, there was a trend toward an association between CC230 and these complications. ACEs were independently associated with 30-day mortality (adjusted odds ratio, 1.88; 95% CI, 1.11-3.13).

Conclusions

ACEs are frequent in pneumococcal pneumonia and are associated with increased mortality. The risk factors defined in this study may help identify patients who must undergo close follow-up, including heart rhythm monitoring, and special care to avoid fluid overload, particularly during the first 48 hours of admission. These high-risk patients should be the target for preventive intervention strategies.

Emergence of multidrug resistance among Haemophilus parainfluenzae from respiratory and urogenital samples in Barcelona, Spain

Haemophilus parainfluenzae (HPAR) is a Gram-negative bacterium that can become an opportunistic urogenital pathogen. Recently, multidrug resistant (MDR) strains have emerged. We aim to analyse the epidemiology of HPAR at Hospital Universitari de Bellvitge between 2013 and 2017 to determine its putative role in sexually transmitted infections (STI). Strains were classified by sample origin, and antimicrobial susceptibility was performed by disk-diffusion tested on Mueller-Hinton Fastidious. MDR was defined as the resistance of the antimicrobial to three or more antibiotic class. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE) after restriction with SmaI and Cfr9I. We classified 944 HPAR isolates as being of urogenital (n = 175; 18.5%), respiratory (n = 719; 76.2%), or other (n = 50; 5.3%) origins. Among the urogenital isolates, 50 (28.6%) were MDR, which was significantly higher than that found in respiratory samples (40/719; 5.6%; p < 0.01). The frequency of MDR increased progressively among urogenital samples from 13.3% (2013) to 33.3% (2017) (r = 0.8; p = 0.035). The resistance rates for all 944 episodes were significantly higher for cotrimoxazole (51.4%), tetracycline (46.3%), chloramphenicol (28.0%), ciprofloxacin (21.1%), and ampicillin (20.6%). After PFGE, no clonal relationship was found. Clinical charts were available for 40 symptomatic patients with MDR HPAR infections presenting mostly urethritis (n = 26; 65.0%). In all cases, symptoms were treated effectively with combination therapy. Furthermore, in 10 of those patients with urethritis, MDR HPAR was the only potential pathogen to be identified. The emergence of MDR HPAR is a matter of concern, and the detection as a single pathogen highlights its putative role as cause of STI.

Assessment of trimethoprim-sulfamethoxazole susceptibility testing methods for fastidious Haemophilus spp

OBJECTIVES

To compare the determinants of trimethoprim-sulfamethoxazole resistance with established susceptibility values for fastidious Haemophilus spp., to provide recommendations for optimal trimethoprim-sulfamethoxazole measurement.

METHODS

We collected 50 strains each of Haemophilus influenzae and Haemophilus parainfluenzae at Bellvitge University Hospital. Trimethoprim-sulfamethoxazole susceptibility was tested by microdilution, E-test and disc diffusion using both Mueller-Hinton fastidious (MH-F) medium and Haemophilus test medium (HTM) following EUCAST and CLSI criteria, respectively. Mutations in folA, folP and additional determinants of resistance were identified in whole-genome-sequenced isolates.

RESULTS

Strains presented generally higher rates of trimethoprim-sulfamethoxazole resistance when grown on HTM than on MH-F, independent of the methodology used (average MIC 2.6-fold higher in H. influenzae and 1.2-fold higher in H. parainfluenzae). The main resistance-related determinants were as follows: I95L and F154S/V in folA; 3- and 15-bp insertions and substitutions in folP; acquisition of sul genes; and FolA overproduction potentially linked to mutations in -35 and -10 promoter motifs. Of note, 2 of 19 H. influenzae strains (10.5%) and 9 of 33 H. parainfluenzae strains (27.3%) with mutations and assigned as resistant by microdilution were inaccurately considered susceptible by disc diffusion. This misinterpretation was resolved by raising the clinical resistance breakpoint of the EUCAST guidelines to ≤30 mm.

CONCLUSIONS

Given the routine use of disc diffusion, a significant number of strains could potentially be miscategorized as susceptible to trimethoprim-sulfamethoxazole despite having resistance-related mutations. A simple modification to the current clinical resistance breakpoint given by the EUCAST guideline for MH-F ensures correct interpretation and correlation with the reference standard method of microdilution.

Emerging non-13-valent pneumococcal conjugate vaccine (PCV13) serotypes causing adult invasive pneumococcal disease in the late-PCV13 period in Spain

OBJECTIVE

An early reduction of adult invasive pneumococcal disease (IPD) was observed after the 13-valent pneumococcal conjugate vaccine (PCV13) introduction for children in Spain. We analysed the epidemiology of adult IPD in the late-PCV13 period.

METHODS

This was a prospective multicentre study of adult IPD involving six hospitals. Strains were serotyped, genotyped and studied for antimicrobial susceptibility. The late-PCV13 period was compared with the pre- and early-PCV13 periods.

RESULTS

A total of 2197 episodes were collected-949 in 2008-2009, 609 in 2012-2013 and 639 in 2015-2016. The initial decrease of IPD observed (from 12.3/100 000 to 8.1/100 000; 2008-2009 versus 2012-2013) plateaued in 2015-2016 (8.3/100 000). IPD due to PCV13 serotypes decreased (from 7.7 to 3.5 to 2.3/100 000; p < 0.05), whereas IPD caused by non-PCV13 serotypes increased (from 4.5 to 4.6 to 6.0/100 000; p < 0.05). The most frequent serotypes in the late-PCV13 period were: 8 (15.1%), 3 (10.5%), 12F (7.9%) and 9N (5.4%). These serotypes were related to major genotypes: CC53 (59.8%) and CC404 (30.4%) for serotype 8, CC180 (64.1%) and CC260 (28.1%) for serotype 3, CC989 (91.7%) for serotype 12F and CC67 (84.8%) for serotype 9N. Penicillin-non-susceptibility (21.2%) was associated with serotypes 11A (CC156), 14 (CC156) and 19A (CC320), and macrolide-resistance was related to serotypes 24F and 19A. Rates of pneumococcal meningitis remained stable throughout the periods (ranges 0.9, 0.8 and 1.0/100 000).

CONCLUSIONS

The initial decrease of adult IPD observed after PCV13 introduction for children has been balanced by the rise of non-PCV13 serotypes. The spread of antibiotic-resistant lineages related to non-PCV13 serotypes (11A and 24F) could be a threat for the treatment of serious pneumococcal diseases.

Identification of polysaccharide capsules among extensively drug-resistant genitourinary Haemophilus parainfluenzae isolates

The human commensal Haemophilus parainfluenzae is emerging as an opportunistic multidrug-resistant pathogen. The objectives of this work were to characterise a new capsular operon of extensively drug-resistant (XDR) H. parainfluenzae clinical isolates and study their resistance mechanisms using whole-genome sequencing. All strains were resistant to: ß-lactams, via amino acid changes in PBP3 (S385T, I442F, V511A, N526K and V562I); quinolones, by alterations in GyrA (S84F and D88Y) and ParC (S84F and S138T); chloramphenicol, through the presence of catS; macrolides, via the presence of mel and mef(E)-carrying MEGA element; and tetracycline, through the presence of tet(M) and/or tet(B). Phylogenetic analysis revealed high genomic diversity when compared to the H. parainfluenzae genomes available on the NCBI, the isolates from this study being closely related to the Swiss XDR AE-2096513. A full capsular operon showing homology to that of H. influenzae was identified, in accordance with the observation of a capsular structure by TEM. This study describes for the first time a capsular operon in H. parainfluenzae, a major determinant of pathogenicity that may contribute to increased virulence in XDR clinical isolates. Moreover, phylogenetic analysis suggests the possible spread of an XDR-encapsulated strain in Europe.

The Apicomplexa-specific glucosamine-6-phosphate N-acetyltransferase gene family encodes a key enzyme for glycoconjugate synthesis with potential as therapeutic target

Apicomplexa form a phylum of obligate parasitic protozoa of great clinical and veterinary importance. These parasites synthesize glycoconjugates for their survival and infectivity, but the enzymatic steps required to generate the glycosylation precursors are not completely characterized. In particular, glucosamine-phosphate N-acetyltransferase (GNA1) activity, needed to produce the essential UDP-N-acetylglucosamine (UDP-GlcNAc) donor, has not been identified in any Apicomplexa. We scanned the genomes of Plasmodium falciparum and representatives from six additional main lineages of the phylum for proteins containing the Gcn5-related N-acetyltransferase (GNAT) domain. One family of GNAT-domain containing proteins, composed by a P. falciparum sequence and its six apicomplexan orthologs, rescued the growth of a yeast temperature-sensitive GNA1 mutant. Heterologous expression and in vitro assays confirmed the GNA1 enzymatic activity in all lineages. Sequence, phylogenetic and synteny analyses suggest an independent origin of the Apicomplexa-specific GNA1 family, parallel to the evolution of a different GNA1 family in other eukaryotes. The inability to disrupt an otherwise modifiable gene target suggests that the enzyme is essential for P. falciparum growth. The relevance of UDP-GlcNAc for parasite viability, together with the independent evolution and unique sequence features of Apicomplexa GNA1, highlights the potential of this enzyme as a selective therapeutic target against apicomplexans.

Osteopenia assessed by body composition analysis is related to malnutrition in alcoholic patients

Osteopenia is frequent among alcoholics. Its pathogenesis seems to be multifactorial, including ethanol intake, hormonal changes, liver cirrhosis, and malnutrition. Our objective is to determine the relative role of malnutrition on bone loss. One hundred and eighty-one male alcoholic patients, drinkers of more than 80 g ethanol/day, were included, recording data on the intensity of alcoholism, liver cirrhosis, nutritional assessment based on feeding habits, body mass index (BMI), midarm anthropometrics, subjective nutritional assessment, lean and fat mass by dual energy X-ray absorptiometry (DEXA), serum proteins and insulin growth factor Type I (IGF-I), calcitropic hormones, parathyroid hormone (PTH), osteocalcin 25OHD3, and bone mass assessed by DEXA, which was also performed in 43 healthy controls. Alcoholics showed decreased serum osteocalcin, PTH, 25OHD3, IGF-I, and bone mass. Alcoholics were frequently malnourished with decreased BMI, lean, and fat mass. The loss of bone mass was not related to the alteration of calcitropic hormones, to the intensity of alcoholism, or to the existence of liver cirrhosis, but to malnutrition. For a similar BMI, bone loss was more intense in alcoholics than in controls, especially in those with irregular feeding habits. Although cross-sectional ones, our data suggest that alcoholic osteopenia may be interpreted as a form of nutritional osteoporosis, notwithstanding the influence of other factors.