Molecular epidemiology of drug-resistant Salmonella Typhimurium in Spain.

One hundred and forty-seven Salmonella serotype Typhimurium strains isolated in three provinces in the midwest of Spain were studied. Of these, 93.6% were drug resistant. There were two predominant resistance phenotypes: 43 isolates (29.3%) were resistant to amoxicillin, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole and 27 isolates (18.4%) to amoxicillin, amoxicillin/clavulanic acid, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole. Randomly amplified polymorphic DNA (RAPD) analysis and pulsed field gel electrophoresis (PFGE) were performed for molecular typing. Thirty-six DNA band profiles were differentiated by RAPD, and 38 by PFGE. We found a high level of clonality; 27% of strains were identical by both methods. There were additional smaller clonal lines within every area. The highest discriminatory power was obtained with PFGE, but the greatest degree of genetic diversity was observed among Salmonella Typhimurium using both RAPD and PFGE.

Molecular epidemiology of drug-resistant Salmonella Typhimurium in Spain

One hundred and forty-seven Salmonella serotype Typhimurium strains isolated in three provinces in the midwest of Spain were studied. Ofthese, 93.6% were drug resistant. There were two predominant resistance phenotypes: 43 isolates (29.3%) were resistant to amoxicillin, tetracyclines,chloramphenicol, streptomycin and sulphamethoxazole and 27 isolates (18.4%) to amoxicillin, amoxicillin/clavulanic acid, tetracyclines,chloramphenicol, streptomycin and sulphamethoxazole. Randomly amplified polymorphic DNA (RAPD) analysis and pulsed field gelelectrophoresis (PFGE) were performed for molecular typing. Thirty-six DNA band profiles were differentiated by RAPD, and 38 by PFGE. Wefound a high level of clonality; 27% of strains were identical by both methods. There were additional smaller clonal lines within every area.The highest discriminatory power was obtained with PFGE, but the greatest degree of genetic diversity was observed among SalmonellaTyphimurium using both RAPD and PFGE

Se estudiaron 147 de cepas de Salmonella serotipificadas como Typhimurium procedentes de tres provincias españolas del medio-oeste. El93,6% de ellas eran resistentes a los antimicrobianos. Hubo dos fenotipos de resistencia predominantes: 43 cepas (29,3%) fueron resistentesa amoxicilina, tetraciclinas, cloranfenicaol, estreptomicina y sulfametoxazol, y 27 (18,4%) a amoxicilina, amoxicilina-ácido clavulánico, tetraciclinas,cloranfenicol, estreptomicina y sulfametoxazol. Los distintos patrones de resistencia se determinaron por técnicas de biología molecular:RAPD (Randomly Amplified Polymorphic DNA) y PFGE (Pulsed Field Gel Electrophoresis). Por RAPD se diferenciaron 36 patrones debandas, y por PFGE 38. Se encontró una proporción alta de clones: el 27% de las cepas fueron idénticas por ambos métodos. Además, encada área se encontraron algunos clones diferentes adicionales. Con PFGE se obtuvo el mayor poder discriminatorio, pero el mayor gradode diversidad genética se observó usando ambas técnicas conjuntamente

[Antimicrobial drug resistance in non-typhi Salmonellae in Castilla y Leon]. / Resistencia a antimicrobianos en Salmonella no typhi en Castilla y León.

We studied the antibiotic susceptibility of 309 Salmonella isolates obtained from three hospitals serving the provinces of Salamanca, Avila and Zamora in the region of Castilla y Leon (mid-west Spain). The susceptibility to 18 antibiotics was studied using the agar dilution method, according to NCCLS guidelines, and the most common multiresistance phenotypes were determined for each province. We observed clear susceptibility differences between the two main serotypes found, S. enteritidis and S. typhimurium. Seventy percent of S. typhimurium were resistant to amoxicillin. In 44% of these isolates, amoxicillin resistance was associated with resistance to streptomycin, sulfonamides, tetracyclines and chloramphenicol. S. enteritidis was susceptible to most antibiotics tested; amoxicillin resistance was observed in 23.3%, and nalidixic acid resistance in 49.6%. Resistance to nalidixic acid was higher in S. enteritidis than in any other serotypes. According to NCCLS breakpoints, no strain was resistant to fluoroquinolones. However, according to MENSURA criteria, 9% of S. typhimurium isolates were resistant to ciprofloxacin. Resistance to cotrimazole and gentamicin was less than 10% for all the serotypes tested. The results indicate that S. typhimurium showed greater resistance and a high multidrug resistance rate. Conversely, S. enteritidis showed high resistance only to amoxicillin and nalidixic acid, though in most cases there was no correlation between this resistance and reduced susceptibility to fluoroquinolones.

[Persistent cough caused by Bordetella pertussis. Study of 6 cases]. / Tos persistente por Bordetella pertussis. Estudio de 6 casos.

BACKGROUND: Pertussis is currently an infrequent illness in Spain, since DTP vaccine was introduced. Immunity acquired after immunization is, nevertheless, lower than immunity acquired after the clinical disease, and decreases steadily. After the adolescence, serum levels of antibodies against B. pertussis may not be enough, leading to atypical infections in other wise immunized patients. METHODS: We inoculated, during 6 months, nasal swabs of patients with symptoms of pertussis and of patients with persistent cough on blood agar, MacConkey agar, chocolate agar, charcoal agar and Bordet Gengou agar. RESULTS: We isolated B. pertussis from 6 patients. Five of them were children between 8 and 14 years old, correctly immunized, whose only symptomatology was persistent cough. The only patient incorrectly immunized showed a clinical picture of pertussis. All the patient evolved favorably with erythromycin. CONCLUSIONS: Immunization with DTP drastically reduces the incidence of serious illness but, after some years, do not protect enough against the appearance of milder, atypical pertussis. These data obligate to take into account the possibility of pertussis infection when persistent cough is observed, in absence of any other factors that can justify it.

[Changes in the flora of the oral cavity after oral topical antibiotics. Importance in antimicrobial prophylaxis in surgery of the neck and head]. / Análisis de las modificaciones en la flora de la cavidad bucal tras el uso de antibióticos tópicos orales. Importancia en la profilaxis antimicrobiana en cirugía de cabeza y cuello.

A pilot study using 5 healthy adults was performed to assess the influence of topical antibiotics and antiseptics on oral flora. Samples of saliva were cultured before and after rinsing the mouth with several solutions: clindamycin, amoxyciclin + clavulanic, povidone-iodine and placebo. The results of this study suggest that, by reducing concentrations of oral flora, topical oral antibiotic prophylaxis is justified for patients having a high risk of developing a surgical infectious complications.