Epidemiology and clinical features of community-acquired, healthcare-associated and nosocomial bloodstream infections in tertiary-care and community hospitals.

Classification of bloodstream infections (BSIs) as community-acquired (CA), healthcare-associated (HCA) and hospital-acquired (HA) has been proposed. The epidemiology and clinical features of BSI according to that classification in tertiary-care (TH) and community (CH) hospitals were investigated in a prospective cohort of 821 BSI episodes from 15 hospitals (ten TH and five CH hospitals) in Andalucía, Spain. Eighteen percent were CA, 24% were HCA and 58% were HA. The incidence of CA and HCA BSI was higher in CH than in TH (CA: 3.9 episodes per 1000 admissions vs. 2.2, p <0.01; HCA: 5.0 vs. 2.9, p <0.01), whereas the incidence of HA BSI was lower (7.7 vs. 8.7, p <0.01). In CA and HCA BSI, the respiratory tract was more frequently the source in CH than in TH (CA: 30% vs. 15%; HCA: 20% vs. 9%, p ≤0.03). In HCA BSI, chronic renal insufficiency and tunnelled catheters were less frequent in CH than in TH (11% vs. 26% and 7% vs. 19%, p ≤0.03), although chronic ulcers were more frequent (22% vs. 8%, p 0.008). BSIs as a result of methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa were very rare in CA episodes, although extended-spectrum b-lactamase-producing Escherichia coli (ESBLEC) caused a similar proportion of all BSIs in CA, HCA and HA episodes. Multivariate analysis revealed no significant difference in mortality rates in CH and TH. HCA infections should be considered as a separate class of BSI in both TH and CH, although differences between hospitals must be considered. CA BSIs were not caused by multidrug-resistant pathogens, except for ESBLEC.

Detection of new mutations conferring resistance to linezolid in glycopeptide-intermediate susceptibility Staphylococcus hominis subspecies hominis circulating in an intensive care unit.

Glycopeptides and linezolid are the most widely used antibiotics to treat infections by methicillin-resistant Staphylococcus spp. We report the presence of various isolates of methicillin-resistant S. hominis subsp. hominis with resistance to linezolid and reduced susceptibility to glycopeptides. We studied ten blood culture isolates of S. hominis subsp. hominis from nine patients admitted to our hospital. Etest was used to study susceptibility to antibiotics commonly prescribed against staphylococci. Domain V region of the 23S rRNA gene was amplified and sequenced to detect possible mutations that confer resistance to linezolid. Pulsed-field gel electrophoresis (PFGE) was used for the clonality study of isolates. All isolates were resistant to oxacillin, gentamicin, levofloxacin, cotrimoxazole, and linezolid, and susceptible to tigecycline and daptomycin. Nine of the isolates were resistant to erythromycin and clindamycin, and showed heterogeneous resistance to glycopeptides. C2190T, G2603T, and G2474T mutations were detected in domain V of the 23S rRNA gene. PFGE showed the presence of two different clones. This report alerts to the possible appearance of clinical strains of methicillin-resistant staphylococci with intermediate resistance to glycopeptides, resistance to linezolid, and multiple resistance to other second-line antibiotics.

Measurement of nanomolar levels of psychoactive drugs in urine by adsorptive stripping voltammetry.

Adsorptive stripping voltammetry was used to determine nanomolar levels of the benzodiazepines pinazepam, camazepam, bromazepam and thienodiazepine (BrTDO) in urine. Measurements were made by differential pulse voltammetry at a hanging mercury drop electrode. The influences of various operational conditions on the stripping response were examined. The optimum accumulation potentials and accumulation times were -0.40 V and up to 60 sec for pinazepam, -0.60 V and up to 40 sec for camazepam, -0.40 V and up to 30 sec for bromazepam and -0.60 V and up to 60 sec for BrTDO, respectively. The effects of various urine components on the voltammetric response were also studied, and preliminary separation of the drugs was found necessary because of interference by creatinine and uric acid. The proposed method is appropriate for the determination of the four drugs in urine up to the 1000 ng/ml level with short accumulation periods (10-60 sec). The relative standard deviation for the 500 ng/ml level of the drugs in urine (30-sec accumulation) was less than 3%.

Measurement of polycyclic aromatic hydrocarbons and other pollutants.

A single point study of atmospheric pollution has been carried out in Granada (Spain); suspended particulate matter, sulphur oxides, ammoniac, nitrogen dioxide and polycyclic aromatic hydrocarbons were determined. There were variations in relation to the month and the day of the week. The PAHs have been determined through HPLC, with a mobile phase of acetonitrile-water (75-25). The results of measurements of benzo(a)pyrene were between 1.006 and 0.485 micrograms m-3 in two different periods of sampling.

[Bacteriocinotyping of Klebsiella. A new scheme (author's transl)]. / Bactériocinotypie du genre Klebsiella. A propos d'un nouveau schéma.

A new typing scheme of the genus Klebsiella for studying the production and different sensitivities towards some standard strains is here proposed. Owing to it, 120 Klebsiellae could be classified. The most frequently bacteriocinotypes found were 778 and 768. The overall amount obtained was of 57 different models of activity. As six clinical experiences have confirmed its efficacy, the practical use may now be faced.