José Gutiérrez-Fernández

Evolution of the resistance to antibiotics of bacteria involved in urinary tract infections: A 7-year surveillance study

BACKGROUND We conducted a retrospective analysis on the identification and antibiogram of all bacteria isolated from urine samples with microbiological confirmation of urinary tract infection (UTI) in a Spanish reference hospital over a 7-year period. METHODS A retrospective analysis was performed of the identification and antibiogram data. RESULTS A total of 31,758 uropathogens were isolated. Escherichia coli accounted for the majority (55.2%) of these, followed by Enterococcus faecalis (18.0%) and Klebsiella spp (10.3%). The highest E coli susceptibility rates were to imipenem (93.0%-99.8%), amikacin (97.3%-99.5%), nitrofurantoin (96.7%-98.9%), and fosfomycin (95.3%-100%), and the lowest were to cefuroxime (67.8%-86.4%), ciprofloxacin (61.2%-69.8%), and co-trimoxazole (55.0%-65.5%). We highlight the overall high activity of imipenem, piperacillin-tazobactam, nitrofurantoin, and fosfomycin on isolates versus the low activity of fluoroquinolones, co-trimoxazole, or cephalosporins. The activity of amoxicillin-clavulanic acid and fosfomycin decreased significantly over the 7-year study period. CONCLUSIONS Imipenem and piperacillin-tazobactam appear to be good options for the empiric treatment of UTI acquired in hospital or requiring hospitalization, whereas nitrofurantoin and fosfomycin can be first-choice antibiotics for the treatment of uncomplicated community-acquired cystitis. However, surveillance studies are required to detect resistance to these antibiotics, given that an increase in uropathogen resistance rates may contraindicate its future use in empiric UTI therapy.

Performance of the Sysmex UF1000i system in screening for significant bacteriuria before quantitative culture of aerobic/facultative fast-growth bacteria in a reference hospital.

To evaluate the performance of the Sysmex UF1000i automatic urine screening system in the quantitative culture of fast‐growth aerobic/facultative bacteria.

Rapid detection and identification of strains carrying carbapenemases directly from positive blood cultures using MALDI-TOF MS.

MALDI-TOF MS has been evaluated to detect carbapenemases activity and pathogen identification directly from positive blood cultures. 21 non-carbapenemase producers and 19 carbapenemase producers Enterobacteriaceae and Pseudomonas aeruginosa strains were included in the study. This technique is simple and detects carbapenemases in 4.5h with high sensitivity and specificity.

Activity of melatonin against Leishmania infantum promastigotes by mitochondrial dependent pathway.

Visceral leishmaniasis, a potentially fatal disease, remains a major international health problem. Only a limited number of effective antileishmanial agents are available for chemotherapy, and many of them are expensive with severe side effects or have a markedly reduced effectiveness due to the development of drug resistance. Hence, there is a genuine need to develop a novel effective and less toxic antileishmanial drug. Melatonin, a neurohormone found in animals, plants, and microbes, can participate in various biological and physiological functions. Several in vitro or in vivo studies have reported the inhibitory effect of melatonin against many parasites via various mechanisms, including modulation of intracellular concentrations of calcium in the parasite and/or any other suggested mechanism. Importantly, many of available antileishmanial drugs have been reported to exert their effects by disrupting calcium homeostasis in the parasite. The objective of the present study was to test the efficacy of exogenous melatonin against Leishmania infantum promastigotes in vitro. Interestingly, melatonin not only demonstrated a significant antileishmanial activity of against promastigote viability in tested cultures but was also accompanied by an alteration of the calcium homeostasis of parasite mitochondrion, represented by earlier mitochondrial permeability transition pore opening, and by changes in some mitochondrial parameters are critical to parasite survival. These pioneering findings suggest that melatonin may be a candidate for the development of novel effective antileishmanial agents either alone or in associations with other drugs.

Implementation of a Computerized Decision Support System to Improve the Appropriateness of Antibiotic Therapy Using Local Microbiologic Data

A prospective quasi-experimental study was undertaken in 218 patients with suspicion of nosocomial infection hospitalized in a polyvalent ICU where a new electronic device (GERB) has been designed for antibiotic prescriptions. Two GERB-based applications were developed to provide local resistance maps (LRMs) and preliminary microbiological reports with therapeutic recommendation (PMRTRs). Both applications used the data in the Laboratory Information System of the Microbiology Department to report on the optimal empiric therapeutic option, based on the most likely susceptibility profile of the microorganisms potentially responsible for infection in patients and taking into account the local epidemiology of the hospital department/unit. LRMs were used for antibiotic prescription in 20.2% of the patients and PMRTRs in 78.2%, and active antibiotics against the finally identified bacteria were prescribed in 80.0% of the former group and 82.4% of the latter. When neither LMRs nor PMRTRs were considered for empiric treatment prescription, only around 40% of the antibiotics prescribed were active. Hence, the percentage appropriateness of the empiric antibiotic treatments was significantly higher when LRM or PMRTR guidelines were followed rather than other criteria. LRMs and PMRTRs applications are dynamic, highly accessible, and readily interpreted instruments that contribute to the appropriateness of empiric antibiotic treatments.

Analytical performance of the Alere™ i Influenza A&B assay for the rapid detection of influenza viruses.

Abstract The analytical performance of the new Alere™ i Influenza A&B kit (AL-Flu) assay, based on isothermal nucleic acids amplification, was evaluated and compared with an antigen detection method, SD Bioline Influenza Virus Antigen Test (SDB), and an automated real-time RT-PCR, Simplexa™ Flu A/B & VRS Direct assay (SPX), for detection of influenza viruses. An “in-house” RT-PCR was used as the reference method. Sensitivity of AL-Flu, SDB, and SPX was 71.7%, 34.8%, and 100%, respectively. Specificity was 100% for all techniques. The turnaround time was 13min for AL-Flu, 15min for SDB, and 75min for SPX. The Alere™ i Influenza A&B assay is an optimal point-of-care assay for influenza diagnosis in clinical emergency settings, and is more sensitive and specific than antigen detection methods.

Sysmex UF-1000i performance for screening yeasts in urine

We tested the capacity of the Sysmex UF‐1000i system to detect yeasts in urine by screening a total of 22 132 urine samples received for culture in our microbiology laboratory during 1 year. We also analyzed different dilutions of previously filtered urine inoculated with a strain of Candida albicans. With clinical samples, a single cut‐off point of 50 yeast‐like cells (YLCs)/μL detected candiduria ≥10 000 colony forming units (CFU)/mL and >100 000 CFU/mL with a sensitivity of 87.3%/95.4%, a specificity of 97%, a negative predictive value of 95.9%, and a positive predictive value of 9.3%/5.7%. With the simulated samples, a linear relationship was observed between the dilution factor and the number of cells detected by UF‐1000i. This instrument appears to be able to reliably rule out candiduria of a magnitude of at least 10 000 CFU/mL and facilitate urine sample screening, thereby providing fast results. The Sysmex UF1000i system can be adapted for candiduria screening by the use of an appropriate YLCs/μL cut‐off point that takes account of the prevalence of candiduria in the population.

Evaluation of the rapid RIDAQUICK Campylobacter® test in a general hospital

The study objective was to evaluate the effectiveness of the new rapid immunochromatographic test RIDAQUICK Campylobacter® (r-biopharm AG, Darmstadt, Germany) for the qualitative detection of Campylobacter antigens in pathologic feces from primary and specialist care patients. Three hundred feces samples were studied from patients with diarrhea, 50.6% from adults and 49.4% from children, which were received by our microbiology laboratory for coproculture. Campylobacter culture results, with or without PCR data, served as reference values for the comparative evaluation of RIDAQUICK Campylobacter® findings. Campylobacter was detected in 12.3% of samples. The diagnostic accuracy values of the RidaQuick Campylobacter® versus culture were: sensitivity of 87%, specificity of 97%, and positive and negative predictive values of 77% and 98%, respectively. RIDAQUICK Campylobacter® is a rapid test for the diagnosis of enteritis due to Campylobacter and could be an option for the clinical diagnosis of one of the main causes of bacterial enteritis in resource-limited settings.

Comparison between urine culture profile and morphology classification using fluorescence parameters of the sysmex uf‐1000i urine flow cytometer

To determine the usefulness of the fluorescence parameters generated by Sysmex UF‐1000i flow cytometer for the rapid diagnosis of urinary tract infection by bacilli or cocci.

Seroprevalence of Leishmania infection among asymptomatic renal transplant recipients from southern Spain

The aim of this article is to assess the seroprevalence of Leishmania infection among asymptomatic renal transplant recipients in a population in the south of Spain.