Phenotypic and genotypic evaluation of slime production by conventional and molecular microbiological techniques.

Twenty-nine staphylococcal isolates from different clinical samples were tested for slime production: phenotypic characterization was carried out using Christensen test (tube test) and Congo red agar plate test (CRA plate test), while the presence and expression of icaA and icaD genes were evaluated by real-time PCR. In 79.3% of studied strains there was a concordance between slime production and presence of icaA and icaD genes, and between lack of slime production and absence of both or only one of the tested genes. In four of five strains where positive phenotype was not associated with the presence of ica genes, gene co-expression (evaluated by mRNA determination) was lacking, while in only a case out of five, there was the presence of transcripts without phenotype. Our study, for the first time, introduces real-time PCR for the detection of both icaA and icaD genes and their mRNA and, furthermore, addresses the relationship between slime phenotype absence and mRNA expression, in clinical isolates of coagulase-negative staphylococci.

Ascaris lumbricoides-induced suppression of total and specific IgE responses in atopic subjects is interleukin 10-independent and associated with an increase of CD25(+) cells.

Ascaris presence in humans has been associated with high levels of blood eosinophils and serum IgE. This study was designed to address the influence of Ascaris infection on allergic and inflammatory parameters of atopic subjects. A cross-sectional design was used, and atopic individuals to be assessed were divided into 3 groups including Ascaris-infected, anti-Ascaris IgG-positive (seropositive), and control subjects. All subjects enrolled had positive skin test reactivity to at least 1 perennial or seasonal allergen; however, levels of C-reactive protein, C3, and C4 were within normal range values. Eosinophil percentage was not significantly different among the groups studied. Total IgE and specific anti-Ascaris IgE levels in the seropositive group were significantly higher than concentrations found in both control and infected groups. Interleukin (IL)-4 release in Ascaris-infected patients was significantly increased versus seropositives, who were able to produce more IL-4 than controls. The levels of IL-10 were lower in the seropositives as well as infected subjects in comparison with controls. CD25(+) lymphocyte populations were significantly increased in the infected group versus the seropositives as well as the controls. Lung function tests of some selected seropositive subjects were significantly impaired. The same parameters of a representative infected patient were not different from controls. Our data on T helper type 2 cells (Th2) and regulatory T cells (Treg) features, as well as CD25(+) lymphocyte increase, suggest an Ascaris-induced mechanism leading to parasite survival. Moreover, the stable control of both T helper type 1 cells (Th1) and Th2 immunity cascades, paralleled by the absence of overwhelming inflammatory systemic reactions and lack of allergic syndromes, may result in a favorable host condition.

An unusual case of brain abscess by Gemella morbillorum.

A case of deep brain abscess by Gemella morbillorum is described. Due to high fever, lethargy, severe headache, and the risk of intraventricular rupture of the suppurative lesion, a CT-guided stereotactic aspiration of the abscess was successfully performed. The patient responded well to a 6-week course of meropenem, metronidazole, and fluconazole. Gemella spp. should not be considered as trivial commensals of the mucous membranes, but appear as emerging pathogens involved in endocarditis, septic shock, and necrotizing pneumonia, as well as in serious intracranial infections.