RESUMO
BACKGROUND: Corynebacterium mucifaciens has been mainly isolated from skin, blood and from other normally-sterile body fluids. It has rarely been described as a human pathogen since its description. CASE PRESENTATION: We herein report the first case of cavitary pneumonia due to C. mucifaciens in an immunocompetent man returning from Maghreb. CONCLUSION: C. mucifaciens should be considered as important human pathogen in patients with severe illness and compatible history of exposure even in individuals with no clearly identified immunosuppression.
Assuntos
Infecções por Corynebacterium/diagnóstico , Corynebacterium/isolamento & purificação , Pneumonia Bacteriana/diagnóstico , África do Norte , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/microbiologiaRESUMO
A clinical strain of Klebsiella pneumoniae was found to possess the chromosomal gene bla(SHV-56), encoding a new inhibitor-resistant beta-lactamase with a pI of 7.6. SHV-56 is derived from SHV-11 by the single substitution K234R. This mutation therefore evidences a new critical site for inhibitor resistance among SHV enzymes.
Assuntos
Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , beta-Lactamases/química , beta-Lactamases/genética , Idoso , Substituição de Aminoácidos , Sequência de Bases , Primers do DNA/genética , DNA Bacteriano/genética , Feminino , Genes Bacterianos , Humanos , Ponto Isoelétrico , Cinética , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Dados de Sequência Molecular , Mutagênese Insercional , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Resistência beta-Lactâmica/genética , beta-Lactamases/metabolismoRESUMO
Over a 12-year period, 68 Shigella strains (31 S. sonnei, 30 S. flexneri, 4 S. dysenteriae, and 3 S. boydii strains) were collected in a French University Hospital from the stools of patients who generally had a recent history of travel to various parts of the world (91%), particularly Africa (67%). These strains were often resistant (streptomycin, spectinomycin, trimethoprim, tetracycline, and sulfonamides, 66 to 84%; ampicillin and chloramphenicol, 34 to 38%; nalidixic acid, 4%) and even multiresistant (87%), and they generally carried integrons (81%) of class 1 (21%), class 2 (47%), or both (13%). Class 1 integrons were associated with ampicillin resistance due to the production of an OXA-30 beta-lactamase in S. flexneri and S. dysenteriae. Class 2 integrons were associated with trimethoprim resistance in S. sonnei. Class 1 and class 2 integrons were inserted within transposons Tn21 and Tn7, respectively, themselves located on the bacterial chromosome, except in one strain. Class 1 integrons showed an atypical organization consisting of the insertion sequence IS1 at the 3' end instead of the typical 3' conserved segment and two blaOXA-30 and aadA1 gene cassettes, despite the absence of epidemiological relationships between the strains, and an apparently functional integrase. Class 2 integrons showed the same albeit classical organization with the three dfrA1, sat, and aadA1 gene cassettes. Occasionally, the 3' end was deleted and the aadA1 gene cassette was unexpressed. Thus, integrons contributed only in part to the multidrug resistance of the Shigella strains. The highly conserved organization of integrons might be related to their location within mobile genetic superstructures.
Assuntos
Farmacorresistência Bacteriana/genética , Integrons/genética , Shigella/classificação , Shigella/genética , Antibacterianos/farmacologia , DNA Bacteriano/genética , Humanos , Dados de Sequência Molecular , Shigella/efeitos dos fármacos , Shigella/isolamento & purificaçãoRESUMO
Four patients in an oncology ward developed Bacteroides fragilis bacteremia over a 12-day period. Cross-infection between two of them, due to an imipenem-resistant strain, was demonstrated by epidemiological investigation and genotypic typing methods (arbitrarily primed PCR fingerprinting and nucleotide sequencing of the cfiA genes and upstream IS1186/IS1168 elements).
