Indigenous Dengue Fever, Buenos Aires, Argentina

Fil: Natiello, Marcela. Hospital de Infecciosas “Francisco Javier Muñiz”; Argentina.Fil: Ritacco, Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Argentina.Fil: Morales, María Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas "Dr. Julio Maiztegui"; Argentina.Fil: Deodato, Bettina. Hospital de Infecciosas “Francisco Javier Muñiz”; Argentina.Fil: Picollo, Marisa. Hospital de Infecciosas “Francisco Javier Muñiz”; Argentina.Fil: Dinerstein, Edith. Hospital Interzonal de Agudos “Evita”; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas "Dr. Julio Maiztegui" Argentina

Development and Validation of a Novel Diagnostic Test for Human Brucellosis Using a Glyco-engineered Antigen Coupled to Magnetic Beads.

Brucellosis is a highly contagious zoonosis and still a major human health problem in endemic areas of the world. Although several diagnostic tools are available, most of them are difficult to implement especially in developing countries where complex health facilities are limited. Taking advantage of the identical structure and composition of the Brucella spp. and Yersinia enterocolitica O:9 O-polysaccharide, we explored the application of a recombinant Y. enterocolitica O:9-polysaccharide-protein conjugate (OAg-AcrA) as a novel antigen for diagnosis of human brucellosis. We have developed and validated an indirect immunoassay using OAg-AcrA coupled to magnetic beads. OAg-AcrA was produced and purified with high yields in Y. enterocolitica O:9 cells co-expressing the oligosaccharyltransferase PglB and the protein acceptor AcrA of Campylobacter jejuni without the need for culturing Brucella. Expression of PglB and AcrA in Y. enterocolitica resulted in the transfer of the host O-polysaccharide from its lipid carrier to AcrA. To validate the assay and determine the cutoff values a receiver-operating characteristic analysis was performed using a panel of characterized serum samples obtained from healthy individuals and patients of different clinical groups. Our results indicate that, using this assay, it is possible to detect infection caused by the three main human brucellosis agents (B. abortus, B. melitensis and B. suis) and select different cutoff points to adjust sensitivity and specificity levels as needed. A cutoff value of 13.20% gave a sensitivity of 100% and a specificity of 98.57%, and a cutoff value of 16.15% resulted in a test sensitivity and specificity of 93.48% and 100%, respectively. The high diagnostic accuracy, low cost, reduced assay time and simplicity of this new glycoconjugate-magnetic beads assay makes it an attractive diagnostic tool for using not only in clinics and brucellosis reference laboratories but also in locations with limited laboratory infrastructure and/or minimally trained community health workers.Fil: Ciocchini, Andres Eduardo. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús (San Martin); Argentina;Fil: Rey Serantes, Diego A.. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús (San Martin); Argentina;Fil: Melli, Luciano Jorge. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús (San Martin); Argentina;Fil: Iwashkiw, Jeremy A.. University of Alberta . Department of Biological Sciences . Alberta Glycomics Centre; Estados Unidos de América;Fil: Deodato, Bettina. Hospital Múñiz. Unidad de Enfermedades Infecciosas; Argentina;Fil: Wallach, Jorge. Hospital Múñiz. Unidad de Enfermedades Infecciosas; Argentina;Fil: Feldman, Mario F. University of Alberta . Department of Biological Sciences . Alberta Glycomics Centre; Estados Unidos de América;Fil: Ugalde, Juan E. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús (San Martin); Argentina;Fil: Comerci, Diego J. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús (San Martin); Argentina

Lethal leptospiral pulmonary hemorrhage: an emerging disease in Buenos Aires, Argentina

In the Buenos Aires metropolitan area, 40–100 cases of human leptospirosis are reported annually. Occasional epidemic outbreaks have been characterized by mild leptospiral illness. Severe illness with acute renal failure and extensive cutaneous and visceral hemorrhages (always accompanied by jaundice) has been observed only rarely. A review of our data for 1990–1999 showed that 276 human cases were diagnosed; 43 of these were characterized by pneumonia alone or associated with another syndrome. No severe pulmonary hemorrhage due to leptospirosis was detected in these cases (Table), and the case-fatality rate was <1% (1).Facultad de Ciencias Médica

Lethal leptospiral pulmonary hemorrhage: an emerging disease in Buenos Aires, Argentina

In the Buenos Aires metropolitan area, 40–100 cases of human leptospirosis are reported annually. Occasional epidemic outbreaks have been characterized by mild leptospiral illness. Severe illness with acute renal failure and extensive cutaneous and visceral hemorrhages (always accompanied by jaundice) has been observed only rarely. A review of our data for 1990–1999 showed that 276 human cases were diagnosed; 43 of these were characterized by pneumonia alone or associated with another syndrome. No severe pulmonary hemorrhage due to leptospirosis was detected in these cases (Table), and the case-fatality rate was <1% (1).Facultad de Ciencias Médica

Prepatellar bursitis due to Brucella abortus: Case report and analysis of the local immune response

A case of prepatellar bursitis in a man with chronic brucellosis is presented. Brucella abortus biotype 1 was isolated from the abundant yellowish fluid obtained from the bursa. Clinical and epidemiological data did not suggest a direct inoculation of the agent in the bursa. However, the patient mentioned occasional local trauma due to recreational sports, which may have constituted a predisposing factor. As determined by ELISA, there were higher levels of IgG against Brucella LPS and cytosolic proteins detected in the patient's bursal synovial fluid when compared with serum. Levels of proinflammatory cytokines (tumour necrosis factor alpha, interleukin 1 beta, gamma interferon, interleukin 8 and MCP-1) were higher than in synovial fluids obtained from patients with rheumatoid arthritis and a patient with septic arthritis, and a zymographic analysis revealed a gelatinase of about 92 kDa. These findings indicate that it may be possible to diagnose brucellar bursitis by measuring specific antibodies in the bursal synovial fluid. In addition, our findings suggest a role of increased local levels of proinflammatory cytokines and gelatinases in the inflammatory manifestations of brucellar bursitis.Fil: Wallach, Jorge Carlos. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Delpino, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Scian, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Deodato, Bettina. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Fossati, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Baldi, Pablo Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; Argentin

Hantavirus seoul in a human and rodent population from a marginal area in Buenos Aires City

Se realizó un estudio seroepidemiológico transversal para determinar la circulación de Hantavirus seoul, de distribución mundial y asociado con fiebre hemorrágica con síndrome renal (FHSR), en una población humana (n: 106) de un asentamiento precario de la ciudad de Buenos Aires y en una población de Rattus norvegicus, (n: 29) capturados en el peridomicilio. Se estudiaron además 35 personas, con igual relación epidemiológica, que eran asistidas por hipertensión arterial. La seroprevalencia de anticuerpos antihantavirus en los roedores fue del 31% mientras que no se encontraron indicios serológicos de infección en los humanos.A sero-epidemiological survey was conducted to detect evidence of the circulation of Hantavirus seoul. This virus of worldwide distribution is associated with hemorrhagic fever with renal syndrome. A total of 106 samples from people who live in a marginal area in Buenos Aires City and 29 Rattus norvegicus captured in the surroundings of their houses were tested for specific antibodies. Thirty five samples from hypertensive patients undergoing a follow up health program, living in the same neighbourhood, were also tested. The antibody prevalence in rodents was 31% while no evidence of infection was found in the human samples.Fil: Seijo, Alfredo. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: Pini, Noemi. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Levis, Silvana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; ArgentinaFil: Coto, Hector. Fundación Mundo Sano; Argentina.Fil: Deodato, Bettina. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: Cernigoi, Beatriz. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: de Bassadoni, Diana. Centro de Salud Nº 18; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina

Hantavirus seoul in a human and rodent population from a marginal area in Buenos Aires City

Se realizó un estudio seroepidemiológico transversal para determinar la circulación de Hantavirus seoul, de distribución mundial y asociado con fiebre hemorrágica con síndrome renal (FHSR), en una población humana (n: 106) de un asentamiento precario de la ciudad de Buenos Aires y en una población de Rattus norvegicus, (n: 29) capturados en el peridomicilio. Se estudiaron además 35 personas, con igual relación epidemiológica, que eran asistidas por hipertensión arterial. La seroprevalencia de anticuerpos antihantavirus en los roedores fue del 31% mientras que no se encontraron indicios serológicos de infección en los humanos.A sero-epidemiological survey was conducted to detect evidence of the circulation of Hantavirus seoul. This virus of worldwide distribution is associated with hemorrhagic fever with renal syndrome. A total of 106 samples from people who live in a marginal area in Buenos Aires City and 29 Rattus norvegicus captured in the surroundings of their houses were tested for specific antibodies. Thirty five samples from hypertensive patients undergoing a follow up health program, living in the same neighbourhood, were also tested. The antibody prevalence in rodents was 31% while no evidence of infection was found in the human samples.Fil: Seijo, Alfredo. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: Pini, Noemi. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Levis, Silvana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; ArgentinaFil: Coto, Hector. Fundación Mundo Sano; Argentina.Fil: Deodato, Bettina. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: Cernigoi, Beatriz. Hospital FJ Muñiz. Servicio de Zoonosis; Argentina.Fil: de Bassadoni, Diana. Centro de Salud Nº 18; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina

Receiver-operating characteristic (ROC) analysis of glycoconjugate-magnetic beads assay results.

<p>A) ROC plot. The analysis was carried out considering as positive controls sera of patients with culture-confirmed brucellosis and culture-negative/serologically-positive patients with clinical diagnosis of brucellosis (138 sera), and as negative controls serum samples from blood-donors, healthy individuals occupational-exposed to the pathogen, patients with febrile syndrome and patients with other diseases (350 sera). AUC, area under the ROC curve. Values in parentheses indicate the 95% confidence interval. B) Plot of the diagnostic sensitivity (Se) and specificity (Sp) of the assay as a function of the cutoff value. The dot vertical line indicates the cutoff value that concurrently optimizes Se and Sp (cutoff = 14.18%, Se = 99.28% and Sp = 99.43%). The dash vertical lines indicate the cutoff values for which maximal Se or Sp is achieved (cutoff = 13.20%, Se = 100% and Sp = 98.57%; cutoff = 16.15%, Se = 93.48% and Sp = 100%).</p