Genetic characterization of Toxoplasma gondii from human and chicken isolates from Argentina.

This study aimed to determine the nPCR-RFLP genotypes of newly obtained T. gondii isolates from human congenital toxoplasmosis cases in Argentina and to determine their allelic profiles for virulence genes ROP18/ROP5. In addition, the ROP18/ROP5 profiles were also determined for previously characterized T. gondii samples. Isolation from congenital toxoplasmosis cases was carried out in mouse bioassay from two placentas (P1 and P2). Genotyping for the new human isolates was performed by nPCR-RFLP using 10 markers. The samples analyzed for ROP18/ROP5 included the two newly obtained isolates (from the congenital toxoplasmosis cases) and nine previously genotyped T. gondii DNA samples from humans and chickens. The results for P1 and P2 named as TgHm18-02Arg and TgHm19-01Arg showed ToxoDB genotypes #14 (non-archetypal) and #2 (clonal type III), respectively. Non-archetypal #14 has been isolated from human cases before in Argentina. However, this is the first report of T. gondii clonal type III in a human case in the country. The ROP18/ROP5 combination was detected in nine samples: 3/3 (n = 1), 4/3 (n = 4), 4/4 (n = 3), and 3-4/4 (n = 1). Notably, the 4/4 profile was identified for the first time and exclusively in T. gondii samples from Misiones province (which borders southern Brazil). Further studies are required to corroborate the regionalization of the ROP18/ROP5 profiles in Argentina.

Consenso Argentino de toxoplasmosis congénita 2020 / Argentine Consensus of congenital toxoplasmosis

Resumen La transmisión vertical de la infección por Toxoplasma gondii ocurre cuando la madre se infecta por primera vez en el transcurso del embarazo. El diagnóstico de la infección materna y la del re cién nacido se logra con el conjunto de pruebas serológicas, hallazgos clínicos y ecográficos. El reconocimiento temprano de la infección materna permite un tratamiento que reduce la tasa de transmisión y el riesgo de daño en el producto de la concepción. El objetivo de este consenso de expertos fue revisar la literatura científica para actualizar las recomendaciones de práctica clínica respecto de la prevención, el diagnóstico y el tratamiento de la toxoplasmosis congénita en nuestro país.

Abstract Mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. Diag nosis of maternal infection and the newborn is achieved by a combination of serological tests, clinical features and ultrasound images. An early diagnosis of maternal infection allows treatment that offers a reduction both in transmission rate and risk of congenital damage. The aim of this expert consensus was to review the scientific literature which would enable an update of the clinical practice guideline of prevention, diagnosis and treatment of congenital toxoplasmosis in our country.

[Argentine consensus of congenital toxoplasmosis]. / Consenso argentino de toxoplasmosis congénita 2020.

Mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. Diagnosis of maternal infection and the newborn is achieved by a combination of serological tests, clinical features and ultrasound images. An early diagnosis of maternal infection allows treatment that offers a reduction both in transmission rate and risk of congenital damage. The aim of this expert consensus was to review the scientific literature which would enable an update of the clinical practice guideline of prevention, diagnosis and treatment of congenital toxoplasmosis in our country.

La transmisión vertical de la infección por Toxoplasma gondii ocurre cuando la madre se infecta por primera vez en el transcurso del embarazo. El diagnóstico de la infección materna y la del recién nacido se logra con el conjunto de pruebas serológicas, hallazgos clínicos y ecográficos. El reconocimiento temprano de la infección materna permite un tratamiento que reduce la tasa de transmisión y el riesgo de daño en el producto de la concepción. El objetivo de este consenso de expertos fue revisar la literatura científica para actualizar las recomendaciones de práctica clínica respecto de la prevención, el diagnóstico y el tratamiento de la toxoplasmosis congénita en nuestro país.

[Prevalence of anti-Toxoplasma gondii antibodies in pregnant women in seven hospitals in Buenos Aires area. Comparison 2006 vs. 2017]. / Prevalencia de anticuerpos anti-Toxoplasma gondii en embarazadas en siete hospitales de Buenos Aires. Comparación entre 2006 y 2017.

We analyzed the presence of IgG and IgM anti-Toxoplasma gondii, as a measure of infection, in pregnant women attending seven hospitals in the Metropolitan Area of Buenos Aires during 2006 and 2017. T. gondii seroprevalence in 2006 vs. 2017, was: Hospital Alemán: 22 and 17% (p = 0.004), Hospital Fiorito: 44 and 33% (p < 0.001), Hospital Gandulfo: 30 and 34% (p 0.025), Hospital Grierson 60 and 44% (p < 0.001), Hospital Rivadavia: 59 and 51% (p = 0.003), Hospital Sardá: 47 and 39% (p < 0.001), and Hospital Thompson: 61 and 51% (p < 0.001). The comparison showed a significant decrease in seroprevalence in six hospitals. We also observed a significant decrease in the reactivity for IgM in 2017 compared to 2006 and in the seroprevalence for T. gondii in the overall population of pregnant women in the study. This means that a greater number of women are susceptible to develop acute infection during pregnancy.

Se analizó de forma retrospectiva la presencia de anticuerpos séricos IgG e IgM anti-Toxoplasma gondii en las embarazadas que concurrieron a siete hospitales del área Metropolitana de Buenos Aires durante 2006 y 2017. La prevalencia de infección, medida como presencia de anticuerpos, en 2006 vs. 2017, fue: Hospital Alemán: 22 y 17% (p = 0.004), Hospital Fiorito: 44 y 33% (p < 0.001), Hospital Gandulfo: 30 y 34% (p 0.025), Hospital Grierson: 60 y 44% (p < 0.001), Hospital Rivadavia: 59 y 51% (p=0.003), Maternidad Sardá 47 y 39% (p < 0.001) y Hospital Thompson: 61 y 51% (p < 0.001). La comparación demostró una disminución estadísticamente significativa de la seroprevalencia en seis hos pitales. También disminuyeron significativamente la reactividad para IgM en 2017 respecto de 2006 y la seroprevalencia para T. gondii en el total de la población de embarazadas estudiadas, lo que significa un mayor número de mujeres susceptible de desarrollar infección aguda durante el embarazo.

Prevalencia de anticuerpos anti-Toxoplasma gondii en embarazadas en siete hospitales de Buenos Aires: Comparación entre 2006 y 2017 / Prevalence of anti-Toxoplasma gondii antibodies in pregnant women in seven hospitals in Buenos Aires area. Comparison 2006 vs. 2017

Se analizó; de forma retrospectiva la presencia de anticuerpos só;©ricos IgG e IgM anti-Toxoplasma gondii en las embarazadas que concurrieron a siete hospitales del ó;rea Metropolitana de Buenos Aires durante 2006 y 2017. La prevalencia de infecció;n, medida como presencia de anticuerpos, en 2006 vs. 2017, fue: Hospital Alemán: 22 y 17% (p = 0.004), Hospital Fiorito: 44 y 33% (p < 0.001), Hospital Gandulfo: 30 y 34% (p 0.025), Hospital Grierson: 60 y 44% (p < 0.001), Hospital Rivadavia: 59 y 51% (p=0.003), Maternidad Sardá 47 y 39% (p < 0.001) y Hospital Thompson: 61 y 51% (p < 0.001). La comparació;n demostró; una disminució;n estadísticamente significativa de la seroprevalencia en seis hos pitales. Tambín disminuyeron significativamente la reactividad para IgM en 2017 respecto de 2006 y la seroprevalencia para T. gondii en el total de la població;n de embarazadas estudiadas, lo que significa un mayor nó;ºmero de mujeres susceptible de desarrollar infecció;n aguda durante el embarazo.

We analyzed the presence of IgG and IgM anti- Toxoplasma gondii, as a measure of infection, in pregnant women attending seven hospitals in the Metropolitan Area of Buenos Aires during 2006 and 2017. T. gondii seroprevalence in 2006 vs. 2017, was: Hospital Alemán: 22 and 17% (p = 0.004), Hospital Fiorito: 44 and 33% (p < 0.001), Hospital Gandulfo: 30 and 34% (p 0.025), Hospital Grierson 60 and 44% (p < 0.001), Hospital Rivadavia: 59 and 51% (p = 0.003), Hospital Sardá: 47 and 39% (p < 0. 001), and Hospital Thompson: 61 and 51% (p < 0.001). The comparison showed a significant decrease in seroprevalence in six hospitals. We also observed a significant decrease in the reactivity for IgM in 2017 compared to 2006 and in the seroprevalence for T. gondii in the overall population of pregnant women in the study. This means that a greater number of women are susceptible to develop acute infection during pregnancy.

Congenital human toxoplasmosis caused by non-clonal Toxoplasma gondii genotypes in Argentina.

Toxoplasmosis, a worldwide distributed zoonosis, can be transmitted congenitally affecting fetuses and developing variable clinical signs. Different Toxoplasma gondii genotypes and infective dose are related factors with different clinical manifestations. Several studies indicate that atypical strains could produce more severe clinical manifestations compared to typical strains. Umbilical cord blood (n = 37) and placenta (n = 19) were collected at birth from women with acute T. gondii infection and processed for isolation by mice bioassay. Six isolates were obtained and identified as TgHm14-4Arg, TgHm15-02Arg, TgHm16-01Arg, TgHm16-02Arg, TgHm17-01Arg and TgHm17-02Arg. Three genotypes described previously on Toxo-DB were identified: #138 identified in chickens from Brazil, #182 isolated from eared doves from Brazil, #14 from wallaby kangaroos and chickens from Argentina, chickens from Brazil, Colombia, Chile and Venezuela, cats and dogs from Brazil and Colombia and also coyotes from USA indicating worldwide distribution of these genotypes. Two new allele combinations were obtained showing high genotypes diversity in Argentina. Four of the isolates (TgHm14-4Arg, TgHm15-02Arg, TgHm16-01Arg, TgHm16-02Arg) and two of them (TgHm17-01Arg, TgHm17-02Arg) produced chronic and acute infections in mice, respectively. Until now, seven T. gondii isolates have been obtained from humans in Argentina, and all were atypical or non-clonal genotypes. The identification of atypical strains causing congenital toxoplasmosis and circulating in our region, make important to perform the serological screenings according Argentine Consensus of Toxoplasmosis and to apply and monitoring treatments earlier in pregnancy. To achieve this aim, it is necessary to inform general population about T. gondii infection, diagnostics and control measures. These results should serve to generate awareness about congenital toxoplasmosis in South America.

[Prevalence of anti-Toxoplasma gondii antibodies in blood donors in Buenos Aires city, from 1967 to 2017]. / Prevalencia de anticuerpos anti-Toxoplasma gondii en hemodonantes en la ciudad de Buenos Aires, desde 1967 a 2017.

A prevalence study of antibodies anti Toxoplasma gondii in voluntary blood donors who attended the hemotherapy service at the Hospital Alemán during the first four months of the years 1997, 2007 and 2017 was carried out and the results were compared to the study carried out in 1967. The sera where processed with the Sabin Feldman Dye Test. The global average seroprevalence in 1967 was 67.0% (CI95%, 64.4%-69.6%); in 1997, 35.0% (CI95%, 33.3%-38.3%); in 2007, 31.9% (CI95%, 29.6%-34.2%) and in 2017, 21.2% (CI95%, 19.0%-23.3%). In the fifty years covered by the study the decline in prevalence was 45.8%, which represents an average annual decline of 0.9%.The decline was statistically significant between 1967 and 1997, and between 2007 and 2017. The four studies demonstrate that infection prevalence increased depending on age. The infection rate for 1967 was 1.0% per year and declined in the next studies to 0.8% in 1997, 0.8% in 2007, and 0.5% in 2017. Donors from the last study responded to a survey that showed a statistically significant correlation between seroprevalence of Toxoplasma gondii antibodies and lack of tap water, unfinished secondary studies or residence in the western or southern part of the Buenos Aires metropolitan area. No significant association was found with having a cat as a pet, the consumption of undercooked meat or the practice of gardening.

Prevalencia de anticuerpos anti Toxoplasma gondii en hemodonantes en la ciudad de Buenos Aires, desde 1967 a 2017 / Prevalence of anti-Toxoplasma gondii antibodies in blood donors in Buenos Aires city, from 1967 to 2017

Se estudió la prevalencia de anticuerpos anti Toxoplasma gondii a los dadores voluntarios de sangre que concurrieron durante el primer cuatrimestre de los años 1997, 2007 y 2017 al Servicio de Hemoterapia del Hospital Alemán de Buenos Aires y se compararon los resultados con el estudio efectuado en el año 1967. Los sueros fueron procesados con el Sabin Feldman Dye Test. La seroprevalencia promedio en 1967 fue 67.0% (IC95%, 64.4%-69.6%), en 1997, 35% (IC95%, 33.3%-38.3%), en 2007, 31.9 % (IC95%, 29.6%-34.2%) y en 2017, 21.2% (IC95%, 19.0%-23.3%). En los cincuenta años que abarca el estudio la disminución de la prevalencia fue de 45.8%, que representa una declinación anual promedio del 0.9%. El descenso fue estadísticamente significativo entre los años 1967 y 1997 y entre 2007 y 2017. En los cuatro estudios se observó un incremento de la prevalencia de infección en función de la edad. La tasa de infección calculada para el año 1967 fue 1.0% y disminuyó en los estudios posteriores, a 0.8% en 1997, 0.7% en 2007 y 0.5% en 2017. Los donantes del último estudio respondieron una encuesta que mostró una correlación estadísticamente significativa entre seroprevalencia de anticuerpos anti-Toxoplasma gondii y la carencia de agua corriente, estudios secundarios no concluidos o la residencia en zona oeste o sur del conurbano bonaerense. No se encontró una asociación significativa con tener un gato como mascota, consumo de carne poco cocida o práctica de jardinería.

A prevalence study of antibodies anti Toxoplasma gondii in voluntary blood donors who attended the hemotherapy service at the Hospital Alemán during the first four months of the years 1997, 2007 and 2017 was carried out and the results were compared to the study carried out in 1967. The sera where processed with the Sabin Feldman Dye Test. The global average seroprevalence in 1967 was 67.0% (CI95%, 64.4%-69.6%); in 1997, 35.0% (CI95%, 33.3%-38.3%); in 2007, 31.9% (CI95%, 29.6%-34.2%) and in 2017, 21.2% (CI95%, 19.0%-23.3%). In the fifty years covered by the study the decline in prevalence was 45.8%, which represents an average annual decline of 0.9%.The decline was statistically significant between 1967 and 1997, and between 2007 and 2017. The four studies demonstrate that infection prevalence increased depending on age. The infection rate for 1967 was 1.0% per year and declined in the next studies to 0.8% in 1997, 0.8% in 2007, and 0.5% in 2017. Donors from the last study responded to a survey that showed a statistically significant correlation between seroprevalence of Toxoplasma gondii antibodies and lack of tap water, unfinished secondary studies or residence in the western or southern part of the Buenos Aires metropolitan area. No significant association was found with having a cat as a pet, the consumption of undercooked meat or the practice of gardening.

Fourier transform infrared spectroscopy for rapid identification of nonfermenting gram-negative bacteria isolated from sputum samples from cystic fibrosis patients.

The accurate and rapid identification of bacteria isolated from the respiratory tract of patients with cystic fibrosis (CF) is critical in epidemiological studies, during intrahospital outbreaks, for patient treatment, and for determination of therapeutic options. While the most common organisms isolated from sputum samples are Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in recent decades an increasing fraction of CF patients has been colonized by other nonfermenting (NF) gram-negative rods, such as Burkholderia cepacia complex (BCC) bacteria, Stenotrophomonas maltophilia, Ralstonia pickettii, Acinetobacter spp., and Achromobacter spp. In the present study, we developed a novel strategy for the rapid identification of NF rods based on Fourier transform infrared spectroscopy (FTIR) in combination with artificial neural networks (ANNs). A total of 15 reference strains and 169 clinical isolates of NF gram-negative bacteria recovered from sputum samples from 150 CF patients were used in this study. The clinical isolates were identified according to the guidelines for clinical microbiology practices for respiratory tract specimens from CF patients; and particularly, BCC bacteria were further identified by recA-based PCR followed by restriction fragment length polymorphism analysis with HaeIII, and their identities were confirmed by recA species-specific PCR. In addition, some strains belonging to genera different from BCC were identified by 16S rRNA gene sequencing. A standardized experimental protocol was established, and an FTIR spectral database containing more than 2,000 infrared spectra was created. The ANN identification system consisted of two hierarchical levels. The top-level network allowed the identification of P. aeruginosa, S. maltophilia, Achromobacter xylosoxidans, Acinetobacter spp., R. pickettii, and BCC bacteria with an identification success rate of 98.1%. The second-level network was developed to differentiate the four most clinically relevant species of BCC, B. cepacia, B. multivorans, B. cenocepacia, and B. stabilis (genomovars I to IV, respectively), with a correct identification rate of 93.8%. Our results demonstrate the high degree of reliability and strong potential of ANN-based FTIR spectrum analysis for the rapid identification of NF rods suitable for use in routine clinical microbiology laboratories.

Polymorphisms in the pertussis toxin promoter in Bordetella bronchiseptica veterinary isolates from Argentina.

Five restriction patterns (including a novel one) could be defined by polymerase chain reaction-restriction fragment length polymorphism on the pertussis toxin (PT) promoter region in local veterinary isolates, suggesting that PT gene analysis is a potential molecular marker for Bordetella bronchiseptica detection and typing.