Andrea Vergara

Evaluation of the eazyplex® SuperBug CRE system for rapid detection of carbapenemases and ESBLs in clinical Enterobacteriaceae isolates recovered at two Spanish hospitals

OBJECTIVES To evaluate the performance of the eazyplex(®) SuperBug CRE system, a loop-mediated isothermal amplification (LAMP)-based system, for confirming the presence of carbapenemases in addition to CTX-M-type ESBLs in previously genotypically and/or phenotypically characterized clinical Enterobacteriaceae isolates recovered in two centres in Spain. METHODS A collection of 94 carbapenemase-producing strains previously characterized by conventional PCR and sequencing and a total of 45 prospectively collected isolates with phenotypes compatible with the presence of a carbapenemase were tested with the eazyplex(®) SuperBug CRE system. In both cases, the presence of an ESBL was also assessed. Results were evaluated to establish the accuracy of this rapid LAMP-based system as well as to determine the concordance between all approaches. RESULTS The eazyplex(®) SuperBug CRE system correctly detected bla carbapenemase genes with or without blaCTX-M genes in 100% of the molecularly characterized strains. Absolute concordance (100%) was also observed in the case of isolates with phenotypes compatible with the presence of a carbapenemase with or without an ESBL inferred by susceptibility patterns and phenotypic inhibitory profiles. Determinations performed with the eazyplex(®) SuperBug CRE system took 15 min. CONCLUSIONS The eazyplex(®) SuperBug CRE system proved to be a powerful tool for the detection of different carbapenemases as well as CTX-M-type ESBLs in Enterobacteriaceae with a rapid resolution time. The test has the high-performance parameters attributable to the sensitivity and specificity already demonstrated by LAMP-based assays. These results assure the usefulness of this test for routine rapid confirmation of carbapenemase-producing Enterobacteriaceae.

Evaluation of a Loop-Mediated Isothermal Amplification-Based Methodology To Detect Carbapenemase Carriage in Acinetobacter Clinical Isolates

ABSTRACT Carbapenem-resistant Acinetobacter baumannii is a major source of nosocomial infections worldwide and is mainly associated with the acquisition of OXA-type carbapenemases and, to a lesser extent, metallo-β-lactamases (MBLs). In this study, 82 nonepidemiologically related Acinetobacter strains carrying different types of OXA or MBL enzymes were tested using the Eazyplex system, a loop-mediated isothermal amplification (LAMP)-based method to rapidly detect carbapenemase carriage. The presence/absence of carbapenem-hydrolyzing enzymes was correctly determined for all isolates in <30 min.

Time to Positivity and Detection of Growth in Anaerobic Blood Culture Vials Predict the Presence of Candida glabrata in Candidemia: a Two-Center European Cohort Study

ABSTRACT This study shows the accuracy of exclusive or earlier growth in anaerobic vials to predict Candida glabrata in a large series of candidemic patients from two European hospitals using the Bactec 9240 system. Alternatively, C. glabrata can be predicted by a time to positivity cutoff value, which should be determined for each setting.

Evaluation of a rapid immunochromatographic test for the detection of OXA-48 carbapenemase

We evaluated the OXA-48K-Set, a rapid immunochromatographic test for the detection of Oxacillinase-48 (OXA-48) carbapenemases, among 37 strains expressing OXA-48 and OXA-48-like carbapenemases and 20 additional strains harboring other β-lactamases. The test showed 100% sensitivity and specificity and the results were obtained in 15minutes.

Impact of microbial invasion of amniotic cavity and the type of microorganisms on short‐term neonatal outcome in women with preterm labor and intact membranes

The objective of this study was to evaluate the impact of microbial invasion of the amniotic cavity and the type of microorganisms on pregnancy and short‐term neonatal outcomes in women with preterm labor.

Prevalence of Extended-Spectrum-β-Lactamase- and/or Carbapenemase-Producing Escherichia coli Isolated from Yellow-Legged Gulls from Barcelona, Spain

ABSTRACT Seventy-two (54.5%) out of 132 fecal samples from a group of yellow-legged gulls in Barcelona, Spain, were positive for Escherichia coli producing either extended-spectrum β-lactamases (ESBL) (51.5%), carbapenemase (1.5%), or cephamycinase (1.5%). The isolation of two carbapenemase-producing E. coli strains is a matter of concern.

In vitro activity against Mycobacterium tuberculosis of levofloxacin, moxifloxacin and UB-8902 in combination with clofazimine and pretomanid.

Multidrug resistance has become a problem in the management of tuberculosis, with an urgent need for research into new drugs as well as the development of efficacious drug combinations and regimens. The main objective of this study was to assess and compare the efficacy of three antituberculous combinations (clofazimine/pretomanid/levofloxacin, clofazimine/pretomanid/moxifloxacin and clofazimine/pretomanid/UB-8902) against multidrug-resistant (MDR) and drug-susceptible clinical isolates of Mycobacterium tuberculosis using an in vitro adaptation of the chequerboard assay. A total of 7 MDR and 11 drug-susceptible clinical isolates were studied. The fractional inhibitory concentration index (FICI) was interpreted as synergism when the value was <0.75, antagonism when it was >4 and additive activity between these two values. The FICI of all of the combinations ranged from 1.2 to 2.3, showing additive activity against all of the isolates. No differences were found between MDR and drug-susceptible isolates. In conclusion, the three combinations are effective against M. tuberculosis with equal effects. Moreover, in vitro testing of drug combinations could be useful to predict their clinical use.

Serotype, virulence profile, antimicrobial resistance and macrolide-resistance determinants in Streptococcus agalactiae isolates in pregnant women and neonates in Catalonia, Spain

INTRODUCTION Streptococcus agalactiae, or group B streptococci (GBS), is the main aetiological agent of early neonatal sepsis in developed countries. This microorganism belongs to the gastrointestinal tract microbiota wherefrom it can colonize the vagina and be vertically transmitted to the child either before or at birth, and subsequently cause infection in the newborn. Approximately, 50% of newborns born to women with GBS become colonized, with 1-2% developing early neonatal infection if no preventive intervention is performed. The aim of this study was to characterize and compare serotypes, virulence factors and antimicrobial resistance of GBS isolates collected from pregnant women and newborns in several hospitals in Catalonia. METHODS 242 GBS strains were analyzed including 95 colonizers and 68 pathogenic strains isolated from pregnant women, and 79 strains isolated from neonates with sepsis in order to determine serotype, virulence and antimicrobial resistance. RESULTS Serotype distribution was different among the three groups, with serotypes Ia and II being significantly more frequent among colonizing strains (p=0.001 and 0.012, respectively). Virulence factors bca and scpB were significantly more frequent among neonatal strains than pathogenic or colonizing strains (p=0.0001 and 0.002, respectively). Pathogenic strains were significantly more resistant to erythromycin, clindamycin and azithromycin than their non-pathogenic counterparts. CONCLUSIONS Taking into account that neonatal sepsis represents a significant problem on a global scale, epidemiological surveillance, antimicrobial resistance and GBS virulence at the local level could provide important knowledge about these microorganisms as well as help to improve treatment and prevent invasive infection caused by this microorganism.

Dermatitis by Dermatophilus congolensis

Sir, A 29-year-old male came to our Emergency Department on his return from a trip to Thailand. He presented a pruritic skin rash that had appeared 1 week previously, during the trip. The patient did not present fever, was conscious, well oriented and well hydrated. On physical examination, multiple papules and pustules were observed predominantly on the upper limbs, but there were also some lesions on the trunk and lower limbs. The Tropical Medicine Service he had consulted before travelling to Thailand did not recommend any prophylactic measures. During the trip the patient had swum in rivers and lakes, had walked barefoot and had been bitten by insects. Moreover, he had drunk non-bottled water and had had contact with animals (elephant ride). The skin lesions appeared during his stay in Thailand, where he had received some topical treatment, the name of which he did not remember, and after which no improvement had been observed. Upon his arrival at the Emergency Department skin samples were taken with cotton swabs in Stuart transport medium, and sent for microbiological study. Oral cefadroxil monohydrate 500 mg twice daily for 6 days, deschlorpheniramine maleate 2 mg three times daily, and topical treatment with betamethanose-gentamicin cream were prescribed. In the Microbiology Laboratory the samples where cultured on blood agar, MacConkey agar, Schaedler agar and thioglycollate broth. All culture media were incubated at 37°C 5%

Evaluation of Lipocalin-2 as a Biomarker of Periprosthetic Joint Infection

BACKGROUND Periprosthetic joint infection (PJI) remains a major clinical challenge. In this study, we evaluated the diagnostic performance of lipocalin-2 (LCN2), a well-characterized neutrophil protein, in synovial fluid to discriminate PJI and aseptic implant failure. METHODS Synovial fluid from patients with acute or chronic PJI, aseptic failure, or controls was obtained during surgery. LCN2 was quantified using a modified enzyme immunoassay coupled with chemiluminescence (Architect Urine NGAL; Abbott Laboratories). RESULTS Synovial fluid was collected from 72 patients: 22 (30.6%) proven infections, 22 (30.6%) aseptic implant failures, and 28 (38.8%) controls. Synovial fluid was obtained from the hip in 18 (25%) and knee in 54 (75%) cases. Among infections, there were 16 (22.2%) acute and 6 (8.3%) chronic PJIs. The median (interquartile range) LCN2 concentration in synovial fluid was 1536.5 ng/mL (261.8-12,923) in the infection group, 87.0 (54.8-135) in the aseptic group, and 55 (45-67.8) in the control group (P < .001). LCN2 discriminated nearly perfectly between controls and confirmed infection (area under the receiver operating characteristic 0.98, 95% confidence interval 0.95-1.00). The optimal cut-off value for maximal sensitivity (86.3%) and specificity (77.2%) to discriminate aseptic failure versus proven infection was 152 ng/mL, with an area under the receiver operating characteristic of 0.92 (95% confidence interval 0.84-0.99). CONCLUSION LCN2 is a potential novel biomarker that may be helpful to inform surgical teams on the potential risk of PJI and optimize specific surgical interventions as it distinguishes between septic and aseptic failure of prosthesis with high sensitivity and specificity.