Spatial-temporal survey of Microcystis oligopeptide chemotypes in reservoirs with dissimilar waterbody features and their relation to genetic variation.

The ability of cyanobacteria to produce toxins and other secondary metabolites is patchily distributed in natural populations, enabling the use of cellular oligopeptide compositions as markers to classify strains into ecologically-relevant chemotypical subpopulations. The composition and spatiotemporal distribution of Microcystis chemotypes within and among waterbodies was studied at different time scales by analyzing (i) Microcystis strains isolated between 1998 and 2007 from different Spanish reservoirs and (ii) individual Microcystis aeruginosa colonies collected from pelagic and littoral habitats in Valmayor reservoir (Spain) during a bloom. No agreement between chemotypes and both morphotypes and genotypes (based on cpcBA-IGS, 16S-23S rRNA ITS and mcyB genes) was found, suggesting that oligopeptide profiles in individual strains evolve independently across morphospecies and phylogenetic genotypes, and that the diversity of microcystin variants produced cannot be explained by mcyB gene variations alone. The presence of identical chemotypes in spatially-distant reservoirs with dissimilar trophic state, lithology or depth indicate that waterbody characteristics and geographical boundaries weakly affect chemotype composition and distribution. At smaller spatiotemporal scales (i.e. during bloom), M. aeruginosa populations showed high number of chemotypes, as well as marked differences in chemotype composition and relative abundance among the littoral and pelagic habitats. This indicates that the factors influencing chemotype composition, relative abundance and dynamics operate at short spatial and temporal scales, and supports emerging hypotheses about interactions with antagonistic microorganisms as possible drivers for widespread chemical polymorphisms in cyanobacteria.

First Spanish case of nocardiosis caused by Nocardia takedensis.

Nocardia takedensis is a recently described species isolated from soil. The first clinical isolate in Japan has recently been reported. This report describes the first clinical isolate of N. takedensis in Spain from a respiratory specimen.

Genotyping of Mycobacterium tuberculosis over two periods: a changing scenario for tuberculosis transmission.

OBJECTIVE: To evaluate changes in the molecular epidemiology of tuberculosis (TB) in Zaragoza, Spain, over a decade that has seen large social and health changes, including the attenuation of the human immunodeficiency virus (HIV) epidemic and increased immigration. DESIGN: A population-based molecular study was conducted using standard restriction fragment length polymorphism IS6110 typing that included all patients with bacteriologically confirmed TB living in the Zaragoza area from 2001 to 2004. The current situation was compared with that described in a previous study from 1993 to 1995. RESULTS: A total of 454 Mycobacterium tuberculosis isolates were genotyped; 239 (52.6%) were grouped in 45 clusters composed of 2 to 85 isolates. Independent risk factors for clustering were identified. The main differences with the previous study were the increase of TB cases among immigrants, a decrease in HIV-TB co-infected patients and the occurrence of a large TB outbreak involving 85 patients (M. tuberculosis Zaragoza [MTZ] strain). CONCLUSION: A change in the epidemiological pattern of TB has been observed in the last years. TB transmission is more common among the Spanish-born population, while foreign birth is significantly less associated with clustering. A single epidemic strain caused 18.7% of all TB cases.

Enfermedad pulmonar por M. Kansasii: Análisis de 33 casos / No disponible

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Systematic molecular characterization of multidrug-resistant Mycobacterium tuberculosis complex isolates from Spain.

We used spoligotyping and restriction fragment length polymorphism (RFLP) of the IS6110-insertion sequence to study the molecular epidemiology of multidrug-resistant (MDR) tuberculosis in Spain. We analyzed 180 Mycobacterium tuberculosis complex isolates collected between January 1998 and December 2000. Consecutive isolates from the same patients (n = 23) always had identical genotypes, meaning that no cases of reinfection occurred. A total of 105 isolates (58.3%) had unique RFLP patterns, whereas 75 isolates (41.7%) were in 20 different RFLP clusters. Characterization of the katG and rpoB genes showed that 14 strains included in the RFLP clusters did not actually cluster. Only 33.8% of the strains isolated were suggestive of MDR transmission, a frequency lower than that for susceptible strains in Spain (46.6%). We found that the Beijing/W genotype, which is prevalent worldwide, was significantly associated with immigrants. The 22 isolates in the largest cluster corresponded to the Mycobacterium bovis strain responsible for two nosocomial MDR outbreaks in Spain.

Mycobacterium malmoense lymphadenitis in Spain: first two cases in immunocompetent patients.

Reported here are two cases of Mycobacterium malmoense lymphadenitis that occurred in two immunocompetent children in Spain. To the best of our knowledge, these are the first documented cases of extrapulmonary infection by M. malmoense in Spain. This report serves to draw attention to this emerging nontuberculous mycobacterium that is gaining increasing recognition as a pulmonary and extrapulmonary pathogen in different countries.

The molecular epidemiology of tuberculosis in Zaragoza, Spain: a retrospective epidemiological study in 1993.

SETTING: The incidence of tuberculosis (TB) in Spain is one of the highest in Europe. In Zaragoza region the incidence rate of tuberculosis and the acquired immune deficiency syndrome (AIDS) are close to the national average. OBJECTIVE: To better define the molecular epidemiology of tuberculosis in an area of Europe where this has not been previously studied. DESIGN: A retrospective epidemiological study on tuberculosis was conducted in Zaragoza, a region of Spain, in 1993. The study population consisted of 226 patients from whom positive culture and complete clinical and demographic data were available. Mycobacterium tuberculosis strains were typed by standard restriction fragment length polymorphism (RFLP). A cluster was defined as two or more isolates with identical RFLP patterns when five or more copies of IS6110 are present. The 137 non-clustered patients were compared with the 89 clustered patients and studied by using univariate analysis. RESULTS: Thirty-nine percent of the patients were clustered, suggesting possible recent transmission. Infection with drug-resistant M. tuberculosis was associated with a decreased risk of being in a cluster. The strains isolated from human immunodeficiency virus (HIV)-positive patients were not associated with clustering. We found that immigration was not a major determinant in the total number of TB cases. CONCLUSION: Immigration, HIV and drug resistance were not associated with recent transmission. More than 50% of the clusters contained two or three patients, indicating that small outbreaks were responsible for most of the tuberculosis cases. Our RFLP typing results indicate that a TB control programme should be implemented in Spain in order to lower transmission of TB.

[Pneumonia diagnosed with bronchoscopy in HIV-positive patients]. / Neumonías diagnosticadas por broncoscopia en pacientes HIV-positivos.

BACKGROUND: The object of our research is to analyse the microbiological results of the samples which have been obtained by means of fibronchoscopy (FB) from HIV positive patients from 1991 until 1993. METHODS: Sixty fibrobronchoscopies were carried out on fifty-seven HIV positive patients. In every case, samples of bronchoaspirate (BAS), bronchoalveolar lavage (BAL) and telescoping plugged catheter (TPC) were cultured; the last two in a quantitative way. Pneumocystis carinii was investigated in BAL by means of immunofluorescence with monoclonal antibodies. RESULTS: Some microorganisms were isolated in forty-seven bronchoscopies. Thirteen episodes resulted negative. The most frequent etiologic agent was Pneumocystis carinii (seventeen cases). The etiology of fifteen episodes was polymicrobial. The intersticial radiological pattern was the predominant one. It was observed in twenty-seven cases. With regard to immunity, 91% of the patients showed CD4 < 200. CONCLUSIONS: In our research work, the samples that have been obtained by means of FB showed a high percentage of diagnoses; that is the reason why we regard this technique as very useful for the diagnosis of pneumonia in patients with AIDS. Due to the large number of bacterian pneumonia, we consider necessary not only the use of BAL, but also that of TPC in these processes.