[Epidemiological study of nasopharyngeal carriers of Streptococcus pneumoniae in children in Murcia region]. / Estudio epidemiológico de portadores nasofaríngeos de Streptococcus pneumoniae en niños en la comunidad autónoma de Murcia.

BACKGROUND AND OBJECTIVES: Streptococcus pneumoniae is a human pathogen that requires prior nasopharyngeal colonization to cause disease. An epidemiological study was conducted on nasopharyngeal carriers of pneumococci in healthy children in Murcia after the introduction of the VCN7, and immediately before the marketing of new vaccines, with the aim of determining the influence of vaccination in our geographic area, and other factors in relation to the state of being a carrier, and the different circulating serotypes. METHODS: A multicentre study was conducted in in 60 primary care health centres in summer 2009 and winter of 2010. A nasopharyngeal swab was collected, and an epidemiological study was carried out on 1562 children aged 1 and 4 years. Of the 1562 nasopharyngeal samples, pneumococci were found in 489 of them, with 343 of them able to be serotyped (70.2%). RESULTS: The prevalence of carriers was 31.3%. Of the patients included, 61.7% (964/1562) had received at least one dose of VCN7. Only 12.8% of the identified serotypes were vaccine serotypes. The independent protective factors against colonization were; Summer time in all age groups, previous vaccination in all the children (OR: 0.75; 95%CI: 0.56-0.93]; P=.01, and in 1-year-olds (OR: 0.6; 95%CI: 0.42-0.84; P=.002), and had taken antibiotics in the last month in the total cohort [OR: 0.69; 95%CI: 0.50-0.96). On the other hand, attendance at school or day-care centre (OR: 1.85; 95%CI: 1.27-2.18; P=.001), number of siblings (OR: 1.3; 95%CI: 1.01-1.91), and passive tobacco smoke exposure (OR: 1.33; 95%CI: 1.02-1.73), were colonization risk factors. The serotypes 6A, 19A, 23B, 15A/B, 11A, 14, 23A/F, 3 y 19F were the most prevalent. CONCLUSIONS: A low proportion of SV was found, with 14, 23F and 19F are persisting. A high prevalence of serotypes 6A and 19A was found. Summer time, vaccination, and the prior administration of antibiotics proved to be protective against colonization, whereas schooling, smoking, and siblings contributed to it.

[Predictive factors of ESBL versus non-ESBL Escherichia coli bacteraemia and influence of resistance on the mortality of the patients]. / Bacteriemia por Escherichia coli: factores predictivos de presencia de bacterias productoras de betalactamasas de espectro extendido e influencia de la resistencia en la mortalidad de los pacientes.

BACKGROUND AND OBJECTIVES: To analyze predictor factors of extended-spectrum betalactamasa (ESBL)-producing E. coli and its repercussion in mortality. PATIENTS AND METHODS: Observational and comparative study of a cohort of non-paediatric admitted patients with E. coli bacteraemia (EB). RESULTS: 153 EB (22% ESBL-producing strains). Risk factors associated with ESBLB: previous antibiotic treatment (OR 2.61; 95% CI 1.1-6.19), severity Winston score ≤2 (OR 9.83, 95% CI 3.42-28.26) and health-related acquired infection (OR 5.35; 95% CI 1.57-18.27). Related mortality rate was 21%, being independent risk factors: cancer (OR 4.02; 95% CI 1.08-14.82), high severity of underlying disease (McCabe) (OR 7.69; 95% CI 1.96-30.09) and critical severity of illness at onset (Winston) (OR 48.89; 95% CI 11.58-206.97). Inappropriate empirical therapy was more frequent in EBSL-producing group (67%, p<0.05). CONCLUSIONS: Previous antibiotic treatment, severity Winston score ≤2 and health-related acquisition are factors associated to ESBL EB. EBSL-producing strains or inadequate treatment were not associated to higher mortality. Factors statistically associated to mortality were cancer, severity of underlying diseases and critical severity of illness at onset.

Antifolate activity of epigallocatechin gallate against Stenotrophomonas maltophilia.

The catechin epigallocatechin gallate, one of the main constituents of green tea, showed strong antibiotic activity against 18 isolates of Stenotrophomonas maltophilia (MIC range, 4 to 256 microg/ml). In elucidating its mechanism of action, we have shown that epigallocatechin gallate is an efficient inhibitor of S. maltophilia dihydrofolate reductase, a strategic enzyme that is considered an attractive target for the development of antibacterial agents. The inhibition of S. maltophilia dihydrofolate reductase by this tea compound was studied and compared with the mechanism of a nonclassical antifolate compound, trimethoprim. Investigation of dihydrofolate reductase was undertaken with both a trimethoprim-susceptible S. maltophilia isolate and an isolate with a high level of resistance. The enzymes were purified using ammonium sulfate precipitation, gel filtration, and methotrexate affinity chromatography. The two isolates showed similar levels of dihydrofolate reductase expression and similar substrate kinetics. However, the dihydrofolate reductase from the trimethoprim-resistant isolate demonstrated decreased susceptibility to inhibition by trimethoprim and epigallocatechin gallate. As with other antifolates, the action of epigallocatechin gallate was synergistic with that of sulfamethoxazole, a drug that blocks folic acid metabolism in bacteria, and the inhibition of bacterial growth was attenuated by including leucovorin in the growth medium. We conclude that the mechanism of action of epigallocatechin gallate on S. maltophilia is related to its antifolate activity.

Heterophile antibodies produce spuriously elevated concentrations of cardiac Troponin I in patients with Legionella pneumophila.

We found an unusually high positive rate for cTnI in patients recently infected with Legionella pneumophila. The aim of this study was to examine the possible origin of increased cTnI levels and to test if it could be associated with the immune response to legionellosis. The cTnI was above the cut point in 46.7% of patients infected with legionellosis when measured with reagent lot number RF421A. A strong correlation between high cTnI measurements and positive serologic values for legionellosis was found. With a revised formulation of cTnI reagent, lot number RF421C, the positive rate decreased by over 10-fold to 3.3%. We conclude that the revised lot of cTnI reagent minimized interference by heterophilic antibodies produced in response to legionellosis.

[Incidence of colonization and infection by Acinetobacter baumannii in an endemic seting (ICU). Analysis of risk factors by means of a surveillance study]. / Incidencia de colonización e infección por Acinetobacter baumannii en una UCI con situación de endemia. Análisis de factores de riesgo mediante un estudio de vigilancia.

BACKGROUND: Our ICU has witnessed a gradual increase in infections due to Acinetobacter baumannii complex that has reached a level of stable endemia since 1995. This situation, aggravated by a high degree of resistance, has led to the present prospective study, designed to establish the incidence of Acinetobacter colonization and to investigate the role of risk factors and their relation to environmental colonization. METHODS: Serial sampling of all patients from the time of ICU admission to discharge. Sample collection from the environment and from hospital personnel. Monitorization of pre-established risk factors and detection of episodes of infection. RESULTS: One-third of patients were colonized during their stay, with the trachea (43%), rectum (31%), and skin (35%) being the most frequent sites. In 92% of cases, colonization was established within the first 9 days after admission. Significant risk factors included mechanical ventilation (p < 0.01) and previous use of antibiotics (p < 0.007). Acinetobacter was recovered from thermometers (35%), respirator switches (43%), and damp surfaces (54%). Infection developed in 8% of patients; all had been previously colonized. CONCLUSIONS: In an endemic setting, Acinetobacter colonization can occur in a third of ICU patients. This event is relatively early and often precedes infection. Duration of mechanical ventilation and previous use of antibiotics are the main risk factors. Environmental elements are frequent bacterial reservoirs, but the main reservoir is the colonized patient.