[Comparison of different methods in order to identify Proteus spp]. / Comparación de diferentes métodos para identificar las especies del género Proteus.

Comparison of different methods in order to identify Proteus spp. The objectives were: (a) to identify Proteus strains to species level, following Farmer's and O'Hara's conventional biochemical reactions; b) to evaluate the sensitivity and specificity of both the API 20E method and a schema of reduced reactions (TSI and MIO agar: motility, indole and ornithine) comparing them with conventional methodology, and c) to evaluate the utility of SDS-PAGE (total proteins) in order to identify Proteus strains to species level. Two hundred and five Proteus spp. clinical isolates, were collected between January 1998 and September 2004, from inpatients and outpatients at Hospital de Clinicas. Strains were identified by means of conventional methodology, the API 20E method, and a schema of reduced reactions. SDS-PAGE (total proteins) was used in 48 out of the 205 strains. The API 20E method identified 79 out of 87 (90.8%) strains of P. mirabilis, 103 out of 103 P. vulgaris complex, and 15 out of 15 P. penneri. Eight strains of P. mirabilis were identified as Proteus spp., the acid production from maltose being necessary to identify them to species level. The schema of reduced reactions identified 205 out of 205 (100%) strains, that is, this schema of reduced reactions identified all the strains to species level without any additional tests, in marked contrast to the API 20E method. The SDS-PAGE (total proteins) identified the three species of the genus, even if the strains of P. mirabilis showed different biochemical reactions.

Comparación de diferentes métodos para identificar las especies del género Proteus / Comparison of different methods in order to identify Proteus spp

Los objetivos de este trabajo fueron: a) identificar a nivel de especie aislamientos de Proteus siguiendo la combinación de los esquemas de Farmer y O'Hara; b) determinar la utilidad del sistema comercial API 20E y de un esquema reducido de pruebas (agar TSI y agar MIO: movilidad, indol y ornitina), comparar estos procedimientos con la metodología convencional y evaluar su sensibilidad y especificidad, y c) evaluar la utilidad del perfil proteico en la identificación de las distintas especies. Se estudiaron 205 aislamientos de Proteus spp. aislados en el período comprendido entre enero de 1998 y setiembre de 2004, recuperados de distintos materiales clínicos correspondientes a pacientes hospitalizados y ambulatorios atendidos en el Hospital de Clínicas. Los organismos fueron identificados mediante la metodología convencional, por el sistema API 20E y con un esquema reducido de pruebas; 48 de ellos fueron sometidos a un SDS-PAGE. API 20E identificó 79 de 87 aislamientos de P. mirabilis (90,8%), 103/103 del complejo P. vulgaris y 15/15 de P. penneri. Ocho aislamientos identificados como Proteus spp. resultaron ser P. mirabilis, al incluir una prueba adicional (maltosa). En la identificación, el esquema reducido coincidió en un 100% con la metodología convencional. A diferencia del sistema API 20E, el esquema reducido alcanza la correcta identificación de todas las especies en laboratorios de baja complejidad, sin la necesidad de pruebas adicionales. El perfil proteico permitió la correcta diferenciación de las tres especies, independientemente de las diferentes atipias de P. mirabilis.

The objectives were: a) to identify Proteus strains to species level, following Farmer's and O'Hara's conventional biochemical reactions; b) to evaluate the sensitivity and specificity of both the API 20E method and a schema of reduced reactions (TSI and MIO agar: motility, indole and ornithine) comparing them with conventional methodology, and c) to evaluate the utility of SDS-PAGE (total proteins) in order to identify Proteus strains to species level. Two hundred and five Proteus spp. clinical isolates, were collected between January 1998 and September 2004, from inpatients and outpatients at Hospital de Clínicas. Strains were identified by means of conventional methodology, the API 20E method, and a schema of reduced reactions. SDS-PAGE (total proteins) was used in 48 out of the 205 strains. The API 20E method identified 79 out of 87 (90.8%) strains of P. mirabilis, 103 out of 103 P. vulgaris complex, and 15 out of 15 P. penneri. Eight strains of P. mirabilis were identified as Proteus spp., the acid production from maltose being necessary to identify them to species level. The schema of reduced reactions identified 205 out of 205 (100%) strains, that is, this schema of reduced reactions identified all the strains to species level without any additional tests, in marked contrast to the API 20E method. The SDS-PAGE (total proteins) identified the three species of the genus, even if the strains of P. mirabilis showed different biochemical reactions.

Diagnostic value of the papanicolaou smear in lower genital tract infections during pregnancy.

OBJECTIVES: To evaluate the diagnostic value of the Pap smear in lower genital tract infections during pregnancy. MATERIALS AND METHODS: A total of 190 pregnant women were examined in the Lower Genital Tract and Colposcopy clinics of the Obstetrics Division at the University Hospital de Clínicas "José de San Martín" of University of Buenos Aires from April to August 1997. Samples were taken from the vaginal fornix for microbiologic study and from the exocervix for Pap smear. Both the sensitivity and specificity test of the Pap smear for diagnosing lower genital tract infections were calculated considering the microbiologic study as the reference standard. RESULTS: The sensitivity of the Pap smear for Candida spp., bacterial vaginosis and Trichomonas vaginalis compared with microbiologic study was 50, 81, and 78, respectively. The specificity for the same study was 96%, 93%, and 100%, respectively. CONCLUSIONS: Pap smear for diagnosing lower genital tract infections is useful when positive results are found for these infections because of its high specificity.