Erythromycin-resistant Streptococcus pyogenes in Argentina.

Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P. Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates deserves to be investigated. The average of ERY-resistance rates obtained in the surveyed centers was 6.7% (range 0.5-14.1%). Control of antimicrobial use should be performed to warrant the future effectiveness of macrolide antibiotics regarding the positive association between use and resistance. These results also suggest that susceptibility tests for macrolides should be performed whenever S. pyogenes is isolated in Argentina.

[Outbreak of histoplasmosis in province of Neuquén, Patagonia Argentina]. / Brote de histoplasmosis en la provincia de Neuquén, Patagonia Argentina.

BACKGROUND: In Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country. AIM: To report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina. METHODS: We evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283. RESULTS: The patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti-Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide. CONCLUSIONS: This outbreak suggests the histoplasmosis endemic area is under the 38° S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history.

Brote de histoplasmosis en la provincia de Neuquén, Patagonia Argentina / Outbreak of histoplasmosis in province of Neuquén, Patagonia Argentina

Antecedentes. La República Argentina no registra casos autóctonos de histoplasmosis en regiones australes del país. Objetivo. Informar de un brote de histoplasmosis ocurrido en Zapala, Provincia de Neuquén, Patagonia Argentina. Métodos. Se evaluó el cuadro clínico y las características epidemiológicas de 5 pacientes involucrados en el brote. Se realizaron estudios ambientales para conocer la fuente de infección. Se analizó el perfil genético generado por RAPD-PCR con los primers 1281-1283 de los aislamientos de Histoplasma capsulatum del caso índice ( CI ) y se comparó con cepas de origen clínico no relacionadas con el brote. Resultados. Los pacientes residían en Zapala y no habían visitado otras áreas geográficas. Todos presentaron un síndrome gripal con imágenes radiológicas micronodulillares diseminadas. El CI necesitó tratamiento específico por la gravedad de su cuadro clínico, y los 4 pacientes restantes presentaron una sintomatología leve y no fueron tratados. La evolución clínica de todos fue favorable. Las cepas de H. capsulatum aisladas de hemocultivo y biopsia pulmonar del CI presentaron un perfil genético diferente al resto de las cepas analizadas. La presencia del hongo en el ambiente pudo inferirse mediante la detección de anticuerpos anti-Histoplasma en suero de ratones BALB/c inoculados con tierra de una alcantarilla que los trabajadores removieron después de un aluvión. Conclusiones. Este brote extiende el área endémica de histoplasmosis por debajo del paralelo 38° de latitud sur. El diagnóstico de histoplasmosis debe considerarse en pacientes de Neuquén, con síntomas compatibles con esta micosis, aun sin existir antecedentes epidemiológicos de viajes a áreas endémicas (AU)

Background: In Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country. Aim: To report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina. Methods: We evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283. Results: The patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti- Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide. Conclusions: This outbreak suggests the histoplasmosis endemic area is under the 38◦ S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history (AU)

Streptococcus pyogenes: sensibilidad a penicilina y eritromicina en las ciudades de Neuquen y Cipolletti / Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti

Hasta la fecha no se ha detectado resistencia a penicilina en Streptococcus pyogenes. No obstante se ha registrado un aumento en la resistencia a macrólidos en varios países del mundo. En la Argentina se han observado escasos porcentajes de resistencia a eritromicina, a excepción de un 11.1 por ciento registrado en Mendoza. El objetivo del presente trabajo fue estudiar la sensibilidad in vitro a penicilina y eritromicina de 251 aislamientos sucesivos de S. pyogenes obtenidos en cuatro centros asistenciales localizados en las ciudades de Neuquén y Cipolletti durante el período abril-diciembre de 1998. Se empleó el método de difusión con discos de penicilina y el método del doble disco (eritromicina 15 Ag y clindamicina 2 Ag) para observar la resistencia a macrólidos y el mecanismo involucrado. Los aislamientos resistentes a macrólidos fueron estudiados por E-test (AB Biodisk, Solna, Suecia) para establecer los niveles de sensibilidad a eritromicina, y por dilución en agar para penicilina, eritromicina, ceftriaxona, azitromicina y clindamicina. Todos los aislamientos fueron sensibles a penicilina y treinta de ellos (12.0 por ciento) fueron resistentes a eritromicina. Estos últimos mostraron el fenotipo M, característico del mecanismo de eflujo activo. Todos los aislamientos resistentes a eritromicina (CIM entre 8 y 16 mg/l) también resultaron resistentes a azitromicina, pero sensibles a clindamicina, penicilina y ceftriaxona. De acuerdo a estos resultados concluimos que S. pyogenes continúa siendo sensible a la penicilina, pero creemos que en nuestra zona es necesario realizar estudios rutinarios de pruebas de sensibilidad a macrólidos debido al relativamente elevado porcentaje de resistencia a eritromicina observado. (AU)

Streptococcus pyogenes: sensibilidad a penicilina y eritromicina en las ciudades de Neuquen y Cipolletti / Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti

Hasta la fecha no se ha detectado resistencia a penicilina en Streptococcus pyogenes. No obstante se ha registrado un aumento en la resistencia a macrólidos en varios países del mundo. En la Argentina se han observado escasos porcentajes de resistencia a eritromicina, a excepción de un 11.1 por ciento registrado en Mendoza. El objetivo del presente trabajo fue estudiar la sensibilidad in vitro a penicilina y eritromicina de 251 aislamientos sucesivos de S. pyogenes obtenidos en cuatro centros asistenciales localizados en las ciudades de Neuquén y Cipolletti durante el período abril-diciembre de 1998. Se empleó el método de difusión con discos de penicilina y el método del doble disco (eritromicina 15 µg y clindamicina 2 µg) para observar la resistencia a macrólidos y el mecanismo involucrado. Los aislamientos resistentes a macrólidos fueron estudiados por E-test (AB Biodisk, Solna, Suecia) para establecer los niveles de sensibilidad a eritromicina, y por dilución en agar para penicilina, eritromicina, ceftriaxona, azitromicina y clindamicina. Todos los aislamientos fueron sensibles a penicilina y treinta de ellos (12.0 por ciento) fueron resistentes a eritromicina. Estos últimos mostraron el fenotipo M, característico del mecanismo de eflujo activo. Todos los aislamientos resistentes a eritromicina (CIM entre 8 y 16 mg/l) también resultaron resistentes a azitromicina, pero sensibles a clindamicina, penicilina y ceftriaxona. De acuerdo a estos resultados concluimos que S. pyogenes continúa siendo sensible a la penicilina, pero creemos que en nuestra zona es necesario realizar estudios rutinarios de pruebas de sensibilidad a macrólidos debido al relativamente elevado porcentaje de resistencia a eritromicina observado.

Erythromycin-resistant Streptococcus pyogenes in Argentina.

Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P.Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6

in 1998-1999 to 9.9

in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates deserves to be investigated. The average of ERY-resistance rates obtained in the surveyed centers was 6.7

(range 0.5-14.1

). Control of antimicrobial use should be performed to warrant the future effectiveness of macrolide antibiotics regarding the positive association between use and resistance. These results also suggest that susceptibility tests for macrolides should be performed whenever S. pyogenes is isolated in Argentina.