Waldemar Francisco

Proteases (caseinase and elastase), hemolysins, adhesion and susceptibility to antimicrobials of Stenotrophomonas maltophilia isolates obtained from clinical specimens

Forty-six S. maltophilia isolates obtained from hospital clinical specimens were studied for protease (caseinase and elastase) production, hemolytic activity, adhesion to HEp-2 cells, plastic and glass. Susceptibility to antimicrobial agents was also evaluated. The majority of isolates were obtained from respiratory tract secretions of patients using medical devices. All the isolates grown overnight were able to hydrolyze casein at 30oC and 37oC. After 72h, all the isolates hydrolyzed elastase at 30oC and 40 isolates (87%) at 37oC. Most of the isolates presented hemolytic activity after 96h of incubation at both temperatures. Rabbit blood showed the hightest hemolytic activity, after 96h 61% and 98% of tested isolates presented b-hemolysis at 30oC and 37oC, respectively. All isolates were susceptible to trimethoprim-sulfametoxazole and were resistant to most b-lactams tested. By the dilution method, S. maltophilia showed a high susceptibility to ticarcillin-clavulanate and a lower susceptibility to ciprofloxacin than the agar diffusion. The isolates showed adhesion to HEp-2 cells, plastic and glass. The proteolytic activities and adhesion to inanimate surfaces detected in S. maltophilia can be related to the pathogenesis of this bacterium and/or medical device colonization which favors the development of nosocomial infections.

Molecular subtyping of Campylobacter jejuni subsp. jejuni strains isolated from different animal species in the state of São Paulo, Brazil

O objetivo do presente trabalho foi caracterizar geneticamente estirpes de Campylobacter jejuni subsp. jejuni isoladas de humanos e de diferentes origens animais (bovinas, suinas, caes, primatas, javalis, suinos e aves de corte). Um total de 828 amostras (fezes, carcacas, fetos abortados e utero histerectomizado) foram analisadas por metodos de rotina bacteriologica e 36 estirpes de C. jejuni foram isoladas. Trinta estirpes de origem fecal humana foram obtidas de laboratorios de analises clinicas da cidade de Sao Paulo. As 66 estirpes de C. jejuni isoladas foram submetidas a caracterizacao genetica. Oligonucleotideos baseados no gene fla A foram usados na reacao de polimerase em cadeia (PCR) e amplificou um fragmento de 702 pb. Os produtos obtidos pela PCR foram avaliados pelas tecnicas de sequenciamento e analise genealogica. Analise da variabilidade genetica das 66 estirpes revelou 44 diferentes subtipos de C. jejuni. Um subtipo de origem humana apresentou sequencia identica a de C. jejuni depositada no GenBank (GENBANK acesso numero AF050186). A subtipagem das estirpes de C. jejuni baseadas no sequenciamento da regiao variavel do gene fla A e na analise do alinhamento das sequencias pelo metodo da Maxima Parcimonia, mostraram-se altamente discriminatorios fornecendo melhores condicoes para a correta diferenciacao entre estirpes originarias de surto e as isoladas esporadicamente. Este foi o primeiro estudo de subtipagem molecular de estirpes de C. jejuni de origem humana e animal utilizando a tecnica do sequenciamento com analise genealogica realizado no Estado de Sao Paulo, Brasil.

Suscetibilidade antimicrobiana in vitro dos Staphylococcus coagulase negativa oculares

PURPOSE: To assess the in vitro susceptibility of conjunctival and corneal coagulase negative Staphylococcus (CoNS) to methicillin, fluoroquinolones and aminoglycosides. METHODS: A total of 707 conjunctival and corneal CoNS disk diffusion test results were retrospectively analyzed, from January 2000 through December 2003. RESULTS: From 2000 to 2003, there was an increase in number of CoNS isolated from conjunctiva (n=57 to n=153) and cornea (n=28 to n=78). The frequency of conjunctival and corneal methicillin-resistant CoNS also increased (1.8 to 19.6% and 14.3 to 29.3%, respectively). There was no statistically significant difference between fluoroquinolones-resistant CoNS percentages in conjunctiva (ofloxacin: 1.8 to 7.8% and ciprofloxacin: 3.5 to 9.2%) and cornea (ofloxacin: 14.3 to 9.0% and ciprofloxacin: 14.3 to 10.3%). Evaluating the results of the conjunctival samples, there was increased resistance to tobramycin (15.8 to 34.0%) and to gentamycin (10.5 to 25.5%). There was no change in resistance of corneal isolates to tobramycin (28.6 to 26.9%) and to gentamycin (21.4 to 23.1%). CONCLUSIONS: there was a decrease in in vitro CoNS susceptibility to methicillin, tobramycin and gentamycin. Fuoroquinolones represented by ofloxacin and ciprofloxacin demonstrated stable in vitro susceptibility.

Fluoroquinolone susceptibilities to methicillin-resistant and susceptible coagulase-negative Staphylococcus isolated from eye infection

PURPOSE To evaluate the fluoroquinolone susceptibilities of ocular isolate coagulase-negative staphylococci (CoNS), identified at the Microbiology Laboratory - UNIFESP. DESIGN Experimental laboratory investigation. METHODS The minimum inhibitory concentrations (MICs) of 21 strains of methicillin-resistant coagulase-negative staphylococci (MRCoNS) and 22 methicillin-sensitive coagulase-negative staphylococci (MSCoNS) to ciprofloxacin, ofloxacin, gatifloxacin and moxifloxacin were determined, using the E-test method standardized by the Clinical and Laboratory Standards Institute (CLSI/NCCLS). RESULTS The MIC90s (microg/ml) for the second generation of tested fluoroquinolones were higher than the fourth generation, especially for the methicillin-resistant coagulase-negative staphylococci group. CONCLUSION Our results indicate that methicillin-sensitive coagulase-negative staphylococci are more susceptible to quinolones than are methicillin-resistant coagulase-negative staphylococci and that fourth generation fluoroquinolones appear to be more potent, affecting even coagulase-negative staphylococcal strains resistant to second generation fluoroquinolones.

Neisseria gonorrhoeae produtora de penicilinase: primeira cepa isolada em São Paulo, SP (Brasil)

Relata-se o primeiro caso identificado de Neisseria gonorrhoeae produtora de penicilinase (NGPP) no Estado de Sao Paulo, Brasil, demonstrando a necessidade de mensurar os indices de prevalencia destas cepas na populacao.Relata-se o primeiro caso identificado de Neisseria gonorrhoeae produtora de penicilinase (NGPP) no Estado de Sao Paulo, Brasil, demonstrando a necessidade de mensurar os indices de prevalencia destas cepas na populacao.