Rev Esp Quimioter 2013:26(3):214-220

Structural dynamics of Legionella pneumophila and Legionella bozemanii colony/biofilm                                
 

MARÍA LUISA GÓMEZ-LUS, MARÍA TERESA CORCUERA, RAFAEL GÓMEZ-LUS, CLAUDIA SÁNCHEZ-SERRANO,
FERNANDO GÓMEZ-AGUADO, MARÍA JOSÉ ALONSO, JOSÉ PRIETO
             

Objectives. The genus Legionella includes very pleomorphic species responsible for disease outbreaks in humans. The appearance of such has great importance to develop artificial biofilms in aquatic ecosystems. The aim of this work was to study the dynamics of growth and evolution of the internal structure of colonies of representative species of the genus as static biofilm model.
Methods. Isolated colonies of Legionella pneumophila and Legionella bozemanii grown in specific media for three and fifteen days were processed for histological methods and embedded in paraffin and epoxy resin for analysis by light microscopy, electron microscopy and image analysis.
Results. In colonies of both species were observed and defined specific architectural patterns, based on stratification and evolve over time. The strata differ in the amount of extracellular matrix, the morphology and population density and the proportion of dead cells. The internal structure of three days colonies showed large differences between L. pneumophila (two layers) and L. bozemanii (four layers). However, in the fifteen days colonies of both species evolved towards a common unique pattern formed by three layers. In both species the growth was also found within the culture medium, although this phenomenon was more intense in L. bozemanii with unique, central and larger invasions.
Conclusions. Our results demonstrate that Legionella colonies on solid culture media are a good model of static biofilm with a complex structural dynamics characterized by the presence of morphological and functional subpopulations. We bring here an histological approach model, allowing, in further research, detailed studies in evolutionary adaptations in multicellular communities to adverse media and to antimicrobials in Legionella species of clinical interest.

Rev Esp Quimioter 2013:26(3):214-220 [pdf]

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Rev Esp Quimioter 2014:27(1):36-42

Use of Digital Health Records and “WebMovil” corporate service in the communication management of critical results of Microbiology, in the context of a primary health care area                                
 

ANTONIO FRANCISCO GUZMÁN-GONZÁLEZ, FEDERICO NAVAJAS-LUQUE, JOSÉ DE LA TORRE-FERNÁNDEZ               

Introduction. The objective was to describe and evaluate a new communication protocol of reporting critical results applied to Microbiology in a health area of Andalusia.
Material and methods. The size and type of the critical values of Microbiology are analyzed for primary care patients. A new computerized reporting system was analyzed, in real time, through Diraya Digital Health Records, which integrates the analytical test module (MPA). The protocol is complemented, in collaboration with the Information Technology (IT), with the Junta de Andalucía short message service (SMS) “WebMovil”.
Results. The total number of notices of critical results by the new protocol in 2012 was 817. The number of critical values for primary care was 570, of which 90 were for Microbiology. The most frequent notice was by isolation in the stool culture (n = 51; 56.67%). The prevalence of the critical values of Microbiology in primary care was 0.45/100. The average time of notifications was 13 minutes. The success rate of notifications was 97.7% and 0% obtained in the number of withdrawals. In 99.93% of cases the contact with the patient was stated and in 98.55% the medical intervention was also confirmed.
Conclusions. Communication by a computerized system linked to the SMS technology showed a reduction in the time of notification, and produced additional benefits, such as eliminating the risk of error when there is no repetition of information from the recipient received by the laboratory. Furthermore, the use of SMS messages ensures that doctors on duty always receive information immediately.

Rev Esp Quimioter 2014:27(1):36-42 [pdf]

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Rev Esp Quimioter 2014:27(3):170-179

Reduction in diabetic amputations over 15 years in a defined Spain population. Benefits of a critical pathway approach and multidisciplinary team work                                 
 

DIEGO DE ALCALÁ MARTÍNEZ-GÓMEZ, M. ANGELES MORENO-CARRILLO, ALVARO CAMPILLO-SOTO, ANDRÉS CARRILLO-GARCÍA, JOSÉ LUÍS AGUAYO-ALBASINI               

Objective. To assess changes in diabetic lower-extremity amputations (LEA) rates in a defined population over a 15-year period, following a multidisciplinary approach including a critical pathway in an inpatient setting with standardized preoperative and postoperative care, as well as in an outpatient setting through the establishment of a diabetic foot clinic.
Methods. This is a study of the incidence and types of LEAs performed in patients with diabetic foot disease complicated admitted to Morales Meseguer Hospital (Murcia, Spain), a large district general hospital, before (1998-2000) and after (2001-2012) of the introduction of better organized diabetes foot care. Hospital and clinic characteristics to the success of the programme are described. All cases of LEA in diabetic patients (1998-2012) within the area were identified by ICD-9-Clinical modification (CM) diagnostic codes. A chi square test was used to compare the frequency and level of amputations.
Results. Over all inpatients with diabetes admitted with foot infections and gangrene, there was a significant decrease in the proportion of total major amputations (47%) and elective major amputations (66%) (p<0.001). The incidence of total major amputations rates per 100.000 of the general population fell with statistical significance (p=0.009). The biggest improvement in LEA incidence was seen in the reduction of major elective amputation with fell 60%, from 7.6 to 3.1 per 100,000 (p<0.001).
Conclusions. Significant reductions in total and major amputations rates occurred over the 15-year period following improvements in foot care services included multidisciplinary teamwork (critical pathway and diabetic foot clinic).

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Rev Esp Quimioter 2013:26(2):81-91

Mathematical modelling of the propagation of infectious diseases: Where we came from, and where we are going                                 
 

MARIA JOSÉ FRESNADILLO-MARTÍNEZ, ENRIQUE GARCÍA-SÁNCHEZ, ENRIQUE GARCÍA-MERINO, ÁNGEL MARTÍN DEL REY, JOSÉ ELÍAS GARCÍA-SÁNCHEZ               

This work deals with the study of the use of mathematical models to simulate the spreading of infectious diseases. There is no doubt about the importance of the use of computational tools that allow the health staff to model and predict the spreading of an infectious disease. Using such tools one can establish and simulate disease control strategies. The development of such technologies is a multidisciplinary issue; in this sense, the mathematical algorithms –that must be computationally implemented- play a central role. The main goal of this work is to highlight among health community the increasing importance of the use of mathematical models for epidemic disease spreading. Consequently, the main features of such models are introduced and their classification is stated taking into account the behavior, the basic population unit or the mathematical objects used. An exhaustive search of related papers through the most important databases (Medline and Web of Science) are performed. The main conclusion obtained from this work is the central role that mathematical models can play in the simulation of epidemic spreading; moreover, some ideas about the future research are stated.

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Rev Esp Quimioter 2013:26(3):221-225

Protection of Enterococcus faecalis in mixed cultures with carbapenemase-producing Escherichia coli and Bacteroides fragilis: effect of the bacterial load                                 
 

DAVID SEVILLANO, LORENZO AGUILAR, LUIS ALOU, MARÍA-JOSÉ GIMÉNEZ, FABIO CAFINI, NATALIA GONZÁLEZ, JOSÉ PRIETO             

Introduction. This study explores effects of pH and inoculum size on imipenem versus tigecycline activity against E. coli, B. fragilis and E. faecalis, both in individual and mixed cultures.
Methods. MIC/MBCs (mg/L) of tigecycline and imipenem were 0.12/≥16 and 4/4 for E. coli, 0.12/0.5 and ≥16/≥16 for B. fragilis, and 0.12/≥16 and 2/≥16 for E. faecalis, respectively. Killing curves in supplemented Brucella broth were performed at pH 7 or 5.8, with two final inocula (≈105 or ≈107 cfu/ml) of each isolate (individual cultures) and with 1:1:1 mixed inocula. Tubes were 48h incubated at 37ºC in anaerobiosis. Final concentrations (estimated concentrations in colon) were 1.50 mg/L for tigecycline and 26.40 mg/L for imipenem, with antibiotic-free curves as controls. Experiments were performed in triplicate.
Results. Imipenem showed inoculum effect against E.coli and B. fragilis, with reductions in initial inocula in experiments with standard inocula contrasting with increases in experiments with high inocula (both individual and mixed cultures). Against E. faecalis no inoculum effect for imipenem was observed in individual cultures, with marked reductions in initial inocula regardless inoculum size. However in mixed experiments the indirect protection of E. faecalis by the two gramnegatives resulted in bacterial regrowth. This protection was inoculum-dependant since it occurred with high but not with standard inocula. Tigecycline reduced initial inocula of the three isolates regardless culture type (individual/mixed) or experimental conditions (pH/inocula size), with lower reductions for the tolerant E. faecalis.
Conclusion. Carbapenemase activity was inoculum-dependant for self-protection and indirect protection of E. faecalis.

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Rev Esp Quimioter 2014:27(1):43-45

Evaluation of galactomannan antigen and Aspergillus real time PCR for diagnosis of invasive aspergillosis                                
 

MERCEDES CHANZÁ, Mª TERESA FRAILE, CONCEPCIÓN GIMENO, Mª DOLORES OCETE               

Introduction. The aim of the study was to compare the galactomannan antigen (GA) and  molecular biology(PCRrt) tests with the culture in the diagnosis of invasive aspergillosis (IA). 
Material and methods. Four hundred and seventy two samples were analyzed: 388 respiratory and 84 serum samples from 271 patients. Culture and GA were evaluated in the respiratory samples and GA in the serum samples. PCR was used when discrepancies were observed among culture and GA tests.
Results. The detection of GA in serum was positive in 22 (of 84), 21 had the test positive respiratory sample. Of the 62 sera with negative GA, 45 were also negative respiratory specimens. The culture was positive in 37 of which were positive for GA. Comparing culture with AG, it showed PPV=23%, NPV=100%, S=100% and E=52%. The PCR showed respect to culture: PPV=69%, NPV=89%, S=64% and E=82%. In sera were found in 60% discrepancies between PCRrt and GA.
Conclusions. We consider useful the GA detection in serum combined with culture and GA in respiratory samples, for diagnosis of AI. PCR requires further studies for standardization and set breakpoints.

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Rev Esp Quimioter 2014:27(3):180-189

State of infection caused by methicillin-resistant Staphylococcus aureus (MRSA) in Extremadura: susceptibility, clonality and role of community-associated MRSA                                 
 


VICENTE AGUADERO, CARMEN GONZÁLEZ-VELASCO, ANA VINDEL, MIGUEL GONZÁLEZ-VELASCO, JUAN JOSÉ MORENO               

The correct surveillance and control of infection caused by methicillin-resistant Staphylococcus aureus (MRSA) needs of update knowledge of its specific properties in each place. Our study aims to describe the current characteristics of infection due to MRSA in Extremadura. During 2010, 309 MRSA were collected from clinical samples in our region. A susceptibility test that included 17 antibiotics tested by AST -588 card Vitek 2 ® and E -test method was performed on all isolates. A sample of 100 strains, selected by stratified random sampling, were genotyped by pulsed field electrophoresis (PFGE). The prevalence of MRSA in Extremadura was 20.2%. Don Benito-Villanueva area showed the most prevalence and a higher incidence. Merida reported the most favourable situation, with a relatively low ratios of prevalence and incidence. The community acquired reached 44 % in the region, showing predominantly in less populated areas (Navalmoral and Coria). The most common multiresistant pattern was tobramycin-levofloxacin-erythromycin (44%), followed tobramycin-erythromycin-clindamycin (20%). No linezolid, daptomycin and tigecycline resistant strains were observed, but 42 % of the MRSA strains showed decreased susceptibility vancomycin (DSV). PFGE analysis reported 27 genotypes, with 3 major genotypes: E8a (25%), E7b (17%) and E7a (12%). The post-hoc statistical analysis did not reveal significant differences in the distribution of genotypes between different areas. However it revealed some trends that should be considered.

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Rev Esp Quimioter 2013:26(2):92-96

Incidence and susceptibility of Campylobacter jejuni in pediatric patients: involvement in bacteremia                                
 

MARÍA JOSÉ GONZÁLEZ-ABAD, MERCEDES ALONSO-SANZ               

Introduction. Invasive disease as a result Campylobacter spp. is rarely reported. Bloodstream infections have been reported in patients with immune deficiency or other serious underlying conditions. We conducted a prospective study to know the incidence of Campylobacter jejuni bacteremia in pediatric patients and its susceptibility to erythromycin and ciprofloxacin.
Methods. The identification of Campylobacter isolates was based on routine culture methods. Antimicrobial susceptibility was performed using a disk diffusion method.
Results. During April 2010-June 2012, at Hospital Niño Jesús of Madrid, Campylobacter spp. was isolated from 171 stool specimens in 154 patients. The median age was 2 years (3 months-21 year). One hundred and one (66%) isolates were identified as C. jejuni. Nine patients with enteritis due C. jejuni (9%) were immunocompromised. Erythromycin resistance was observed in 5% of the isolates. The resistance to ciprofloxacin was 88%. Blood cultures were obtained of 19 patients infected with C. jejuni (19%). Of these, one had C. jejuni bacteremia. During the study period, other episode of C. jejuni bacteremia was detected in one patient different without positive stool culture for C. jejuni (0.34% of all bloodstreams infections). Both patients were immunocompromised.
Conclusions. Campylobacter spp. is an uncommon cause of bloodstream infection in our serie occurring in pediatric patients with immune deficiency as predisposing factor. In our institution, empirical use of fluoroquinolones for Campylobacter infections should not be recommended by the high rate of resistance. Moreover in our study the resistance to erythromycin is low, however is advisable its surveillance.

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Rev Esp Quimioter 2013:26(3):253-260

Control of Chagas disease in pregnant Latin-American women and her children  

 

FRANCISCO J MERINO, ROCÍO MARTÍNEZ-RUIZ, ICIAR OLABARRIETA, PALOMA MERINO, SILVIA GARCÍA-BUJALANCE, TERESA GASTAÑAGA, MARÍA FLORES-CHAVEZ, GRUPO DE ESTUDIO DE LA ENFERMEDAD DE CHAGAS DE LA COMUNIDAD DE MADRID             

Chagas disease is a chronic and systemic infection caused by Trypanosoma cruzi. According to estimates from WHO, 10 million people are affected by this parasite. In the last years, birthrate among the immigrant women from Latin America settled in the Comunidad Autónoma de Madrid has been increasing, and as T. cruzi can be transmitted from mother to child, in fact 11 cases of congenital Chagas disease have been confirmed. Therefore, the aim of this paper is encouraging improvements in the coverage of the anti-T. cruzi antibodies detection in pregnant women from endemic areas. By this strategy, an active search for infected pregnant women and early detection of her infected newborns could be conducted, and then an early specific treatment could be administrated. Thus, there could be an important contribution to the control of Chagas disease in non-endemic area.

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Rev Esp Quimioter 2014:27(1):46-50

Antimicrobial stewardship in patients recently transferred to a ward from the ICU                                
 

ANTONIO RAMOS, LAURA BENÍTEZ-GUTIERREZ, ANGEL ASENSIO, BELÉN RUIZ-ANTORÁN, CARLOS FOLGUERA, ISABEL SÁNCHEZ-ROMERO, ELENA MUÑEZ               

Purpose. Inappropriate use of antibiotics is an important health problem that is related to increasing bacterial resistance. Despite its relevance, many health institutions assign very limited resources to improving prescribing practices. An antimicrobial stewardship programme (APS) centred on patients discharged from the ICU could efficiently undertake this task.
Methods. During this six month study the main activity was performing a programmed review of antimicrobial prescriptions in patients transferred to the ward from the ICU. In the case of inadequate antimicrobial treatment, a recommendation was included in the medical record.
Results. A total of 437 antimicrobial prescriptions for 286 patients were revised during a six month period. In all, 271 prescriptions (62%) were considered inappropriate in 183 patients. The most common reasons for inappropriateness were treating unconfirmed infection (43%), inadequate antimicrobial coverage (34%) and intravenous administration when the oral route was feasible (11%). Proposed recommendations were addressed in 212 cases (78%). There was no significant difference in adherence with respect to the type of recommendation (p=0.417). There was a 5% lower use of antibiotics during the year the study was conducted compared to the previous one.
Conclusions. ASPs centred on patients discharged from the ICU may be an efficient strategy to ameliorate antimicrobial use in hospitals.

Rev Esp Quimioter 2014:27(1):46-50 [pdf]

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