Marine mammals, regarded as sentinels of aquatic ecosystem health, are exposed to different pathogens and parasites under natural conditions. We surveyed live South American fur seals Arctocephalus australis and South American sea lions Otaria flavescens in Uruguay for Leptospira spp., canine distemper virus (CDV), Mycobacterium spp., Toxoplasma gondii, and Neospora caninum. Samples were collected from 2007 to 2013. The seroprevalence of Leptospira spp. was 37.6% positive, 50.9% negative, and 11.5% suspect for A. australis (n = 61) while for O. flavescens (n = 12) it was 67% positive, 25% negative, and 8% suspect. CDV RNA was not detected in any of the analyzed samples. Most animals tested seropositive to tuberculosis antigens by WiZo ELISA (A. australis: 29/30; O. flavescens: 20/20); reactivity varied with a novel ELISA test (antigens MPB70, MPB83, ESAT6 and MPB59). Seroprevalence against N. caninum and T. gondii was 6.7 and 13.3% positive for O. flavescens and 0 and 2.2% positive for A. australis respectively. To evaluate possible sources of infection for pinnipeds, wild rats Rattus rattus and semi-feral cats Felis catus were also tested for Leptospira spp. and T. gondii respectively. Water samples tested for Leptospira revealed saprofitic L. bioflexa. Pathogenic Leptospira were detected in the kidneys of 2 rats, and cats tested positive for T. gondii (100%). These results represent a substantial contribution to the study of the health status of wild pinnipeds in Uruguay.

To investigate seroprevalence of anti-Leptospira antibodies in equines and associated workers in Uruguay, 891 equine and 150 human sera were drawn; 212 equine urine samples were also taken for culture. Environmental conditions and equine raising or managing practices were recorded in all 72 visited establishments; epidemiological information was obtained from each worker. Microscopic agglutination technique (MAT) was performed with 10 Leptospira strains for equines and 18 for human sera, that were also studied with IgM indirect immunofluorescence (IgM-IIF). Equine titres ≥100 were considered positive, and human sera titres ≥200 suggested probable recent or past infection. Urines were cultured in Ellinghausen-McCullough-Johnson-Harris (EMJH) media; local identification of one obtained isolate with lipL32 PCR, Multiple Locus Variable number tandem repeat Analysis and partial rrs gene sequencing, were completed at Institut Pasteur, Paris. Estimated reactivity was 61.3% for equines, which was higher than the studied bovine national levels (21%) and mainly observed with Icterohaemorrhagiae serogroup (40.3%), Sejroe, Canicola, Pomona or Ballum. Aged animals from slaughterhouses and cattle farms were the most frequently positive. Multiple regression analysis confirmed a significant association between seropositivity and equine age. Only one positive culture could be fully studied, and confirmed to be Leptospira interrogans serogroup Canicola; it was added to the MAT antigen panel and revealed fairly frequent reaction with equine and human sera. Three workers (2%) showed titres = 200 with Icterohaemorrhagiae or Canicola serogroups, without recent clinical manifestations. Their attended equines reacted with the same serogroups, suggesting common source infections or infection transmitted by equines. Three other humans yielded titres = 100, and none of the 150 showed an IgM-IIF-positive result. Equines seem not to be an important origin of regional human leptospirosis, except perhaps during acute animal infection. More culture work is required to study intensity and lapses of leptospiruria, as well as to further identify circulating strains.

The aim of this study was to describe the microbiological characteristics and profile of genes encoding enterotoxins in 95 Staphylococcus aureus isolates obtained between April 2011 and December 2014 from foodstuffs, persons and surfaces of retail food stores. After microbiological identification and antimicrobial susceptibility testing, polymerase chain reactions (PCR) were performed, targeting sea, seb, sec, sed and see genes that code for classical enterotoxins (ET) A-E, and three additional genes: seg , seh and sei , coding for so-called "new enterotoxins" G, H and I. The isolates were characterized by Pulsed Field Gel Electrophoresis (PFGE), and five selected isolates were further analyzed through Multi Locus Sequence Typing (MLST). It is noteworthy that 54.7% of the examined isolates harbored one or more of the investigated ET gene types. Most positive isolates carried more than one ET gene up to five types; seg was the most frequent ET gene, followed by sei. Five enterotoxin-coding isolates also coded for some antimicrobial resistance genes. Two of them, and four additional non-enterotoxic isolates carried erm genes expressing inducible clindamycin resistance. PFGE-types were numerous and diverse, even among enterotoxin-coding strains, because most isolates did not belong to known foodborne outbreaks and the sampling period was long. MLST profiles were also varied, and a new ST 3840 was described within this species. ST 88 and ST 72 enterotoxin-coding isolates have been identified in other regions in association with foodborne outbreaks. This manuscript reports the first systematic investigation of enterotoxin genes in S. aureus isolates obtained from foodstuffs and infected people in Uruguay.

Enteroinvasive Escherichia coli (EIEC) cause intestinal illness through the same pathogenic mechanism used by Shigella spp. The latter species can be typed through genomic and phenotypic methods used for E. coli and have been proposed for reclassification within E. coli species. Recently the first appearance of a highly pathogenic EIEC O96:H19 was described in Europe as the causative agent of two large outbreaks that occurred in Italy and in the United Kingdom. In contrast to Shigella spp and to the majority of EIEC strains, EIEC O96:H19 fermented lactose, lacked pathoadaptive mutations, and showed good fitness in extracellular environment, similarly to non-pathogenic E. coli, suggesting they have emerged following acquisition of the invasion plasmid by a non-pathogenic E. coli. Here we describe the whole genome comparison of two EIEC O96:H19 strains isolated from severe cases of diarrhea in Uruguay in 2014 with the sequences of EIEC O96:H19 available in the public domain. The phylogenetic comparison grouped all the O96:H19 strains in a single cluster, while reference EIEC strains branched into different clades with Shigella strains occupying apical positions. The comparison of the virulence plasmids showed the presence of a complete conjugation region in at least one O96:H19 EIEC. Reverse Transcriptase Real Time PCR experiments confirmed in this strain the expression of the pilin-encoding gene and conjugation experiments suggested its ability to mobilize an accessory plasmid in a recipient strain. Noteworthy, the tra region was comprised between two reversely oriented IS600 elements, which were also found as remnants in another EIEC O96:H19 plasmid lacking the tra locus. We hypothesize that an IS-mediated recombination mechanism may have caused the loss of the conjugation region commonly observed in EIEC and Shigella virulence plasmids. The results of this study support the hypothesis of EIEC originating from non-pathogenic E. coli through the acquisition of the virulence plasmid via conjugation. Remarkably, this study showed the ability of a circulating EIEC strain to mobilize plasmids through conjugation, suggesting a mechanism for the emergence of novel EIEC clones.

La leptospirosis equina se cree poco común por ser habitualmente subclínica, pero estúdios recientes sugieren que es una infección extendida geográficamente, con diversos perfiles de incidencia y serovares infectantes. Por su elevado nivel poblacional y su empleo en múltiples tareas, corresponde considerar a los equinos como potencial fuente de infección humana. En Uruguay, hasta el momento, no hay registros de leptospirosis en equinos. Esta enfermedad se asocia principalmente con el reservorio bovino, pero determinados equinos comparten espacios con bovinos y otros animales de producción en establecimientos ganaderos, y en establecimientos de cría existen abundantes roedores atraídos por el alimento y forraje.

Leptospirosis is important in Uruguay due to the economic loss caused by the diseases of production animals, mainly bovines, and also due to frequent human infection. We decided to study anti-Leptospira antibodies in the sera of dairy workers, rice laborers, veterinarians, suburban slum dwellers and garbage recyclers. Our aims were to estimate the seroprevalence of infection by Leptospira spp. in these people at risk, the relative importance of the known risk factors associated with infection, and the impact of human infections in each setting. Groups at risk were identified and 35 visits to their locations were made, conducting field surveys and exchange talks for information and education. Simple epidemiological questionnaires were administered and sera samples were taken from 308 persons. The microagglutination Technique (MAT) and the IgM Indirect Immunofluorescence (IIF) assay were employed to detect antibodies. Environmental water samples, canine and equine sera were also examined. More than 45% of human sera were reactive and the studied groups were confirmed to be widely exposed to infection. Female sera were frequently reactive, though most illnesses occur in men, and the most severe cases in elderly males; the emergence and evolution of the disease may strongly depend on the host condition and functions. Animal contact and unsafe water usage were the main identified risk factors to be considered in prevention. Fifty per cent of the studied horses showed a positive MAT reaction. The underdiagnosis of the illness and its long-term symptoms require further study, as well as greater health and social attention efforts.

Leptospirosis is a neglected zoonosis with worldwide distribution. The causative agents are spirochete bacteria of the Leptospira genus, displaying huge diversity of serovars, the identity of which is critical for effective diagnosis and vaccination purposes. Among many other mammalian species, Leptospira infects cattle, eliciting acute signs in calves, and chronic disease in adult animals often leading to abortions. In South America, and including in Uruguay, beef and dairy export are leading sources of national income. Despite the importance of bovine health, food safety, and bovine-related dissemination of leptospirosis to humans, extremely limited information is available as to the identity of Leptospira species and serovars infecting cattle in Uruguay and the South American subcontinent. Here we report a multicentric 3-year study resulting in the isolation and detailed characterization of 40 strains of Leptospira spp. obtained from infected cattle. Combined serologic and molecular typing identified these isolates as L. interrogans serogroup Pomona serovar Kennewicki (20 strains), L. interrogans serogroup Canicola serovar Canicola (1 strain), L. borgpetersenii serogroup Sejroe serovar Hardjo (10 strains) and L. noguchii (9 strains). The latter showed remarkable phenotypic and genetic variability, belonging to 6 distinct serogroups, including 3 that did not react with a large panel of reference serogrouping antisera. Approximately 20% of cattle sampled in the field were found to be shedding pathogenic Leptospira in their urine, uncovering a threat for public health that is being largely neglected. The two L. interrogans serovars that we isolated from cattle displayed identical genetic signatures to those of human isolates that had previously been obtained from leptospirosis patients. This report of local Leptospira strains shall improve diagnostic tools and the understanding of leptospirosis epidemiology in South America. These strains could also be used as new components within bacterin vaccines to protect against the pathogenic Leptospira strains that are actually circulating, a direct measure to reduce the risk of human leptospirosis.

Introduction . Acute diarrheal disease still deserves worldwide attention due to its high morbidity and mortality, especially in developing countries. While etiologic determination is not mandatory for management of all individual cases, it is needed for generating useful epidemiologic knowledge. Diarrheagenic Escherichia coli (DEC) are relevant enteropathogens, and their investigation requires specific procedures to which resources and training should be dedicated in reference laboratories. Methodology . Following the hypothesis that enteric pathogens affecting children in towns located in the interior of Uruguay may be different from those found in Montevideo, we conducted a diagnostic survey on acute diarrheal disease in 83 children under 5 years of age from populations in the south of the country. Results . DEC pathotypes were the only bacterial pathogens found in diarrheal feces (20.48%), followed by rotavirus (14.45%) and enteric adenovirus (4.81%). Atypical EPEC (aEPEC) was the most frequent DEC pathotype identified, and unexpectedly, it was associated with bloody diarrheal cases. These patients were of concern and provided with early consultation, as were children who presented with vomiting, which occurred most frequently in rotavirus infections. aEPEC serotypes were diverse and different from those previously reported in Montevideo children within the same age group and different from serotypes identified in regional and international studies. Enteroinvasive (EIEC) O96 : H19, associated with large outbreaks in Europe, was also isolated from two patients. Antibiotic susceptibility of pathogenic bacteria identified in this study was higher than that observed in previous national studies, which had been mainly carried out in children from Montevideo. Conclusion . The reduced number of detected species, the marked prevalence of aEPEC, the scarce resistance traits, and the diverse range of serotypes in the virulent DEC identified in this study confirm that differences exist between enteropathogens affecting children from interior towns of Uruguay and those circulating among children in Montevideo.

The aim of this work was to study the prevalence of Listeria monocytogenes in foods obtained in retail shops and food industries located in Montevideo-Uruguay, and to identify the serogroups of the obtained isolates. Three-thousand one-hundred and seventy-five food samples (frozen, deli meats, ready-to-eat and cheese) were analyzed. The obtained isolates were serogrouped by multiplex PCR and serotyped by conventional procedure. Genetic comparisons were performed using pulsed-field gel electrophoresis on a sub-set of isolates belonging to the same serotype successively recovered from the same establishment. L. monocytogenes was isolated from 11.2% of samples. The highest prevalence was observed in frozen foods (38%), followed by cheese (10%). 1/2b and 4b were the most frequently identified serotypes. In six of 236 analyzed establishments we successively recovered L. monocytogenes isolates belonging to the same serotype. Most of them corresponded to serotype 1/2b. Pulsed-field gel electrophoresis profiles suggest that at least 33% of L. monocytogenes 1/2b isolates are genetically related and that may remain viable for prolonged periods. The observed prevalence of L. monocytogenes was lower than reported in neighboring countries. Our findings highlight the role that frozen foods may play in the spread of this pathogen, and the relevance of serotypes 1/2b and 4b.

Laboratory diagnosis of human leptospirosis usually relies on indirect methods exploring specific immune response. Isolation and identification of the involved strains are cumbersome, but can provide biological resources for pathogenic studies and relevant information for guiding prevention and control measures. The aim of the research we are hereby reporting was the characterization of Leptospira isolates obtained from humans and the environment in Uruguay. Blood cultures were performed from early samples of 302 Uruguayan patients, mainly rural workers, and from 36 water samples taken from their living or working environments. Eight human isolates and seven environmental isolates were obtained and analyzed by end point Polymerase Chain Reaction (PCR), Multilocus Variable Number of Tandem Repeat Analysis (MLVA) and other molecular methods. Human isolates corresponded to several serogroups and serovars of Leptospira interrogans and Leptospira kirschneri species, probably reflecting the infection with similar involved Leptospira species and serovars of an extended animal reservoir in rural settings of the country, mostly dedicated to meat and dairy production. Culture-positive patients were older than usually affected workers, and presented signs and symptoms of severe illness. A high organic and circulating bacterial burden may explain an easier positive result from these workers' samples. Environmental isolates were mainly identified as Leptospira biflexa strains, with a single L. meyeri isolate of uncertain significance.

La leptospirosis bovina es una enfermedad reproductiva muy importante en los bovinos ya que causa problemas de infertilidad en los rodeos de cria y considerables perdidas economicas. Ademas es una zoonosis ocupacional de incidencia alta en personal de campo y veterinarios, por exposicion directa o indirecta a la orina de vacas, abortamientos, fetos al momento del parto, cesareas o durante el diagnostico de gestacion. El objetivo de este articulo es la descripcion de casos de abortamientos producidos por leptospirosis. Los animales afectados fueron vacas y vaquillonas, produciendose abortamientos en el 44% de los vientres prenados. Las vacas abortadas que se examinaron clinicamente presentaron retencion de placenta y leve decaimiento. Los abortos se produjeron a termino, o terneros que nacian muertos. Se realizo necropsia de tres terneros abortados, observando-se ictericia y hemorragia generalizada, mucosas toxemicas, hepatomegalia e higado de color ladrillo, y leve esplenomegalia. Se remitieron muestras de higado, rinon, bazo, y pulmon; ademas de orina, liquido abomasal y sangre cardiaca al Departamento de Bacteriologia y Virologia del Instituto de Higiene de la Facultad de Medicina de la Universidad de la Republica. Se sembraron en total 11 muestras en medios de cultivo EMJH y Fletcher. Se observo crecimiento de espiroquetas por microscopia de la morfologia a fondo oscuro en los cultivos de bazo, sangre cardiaca, pulmon y liquido abomasal. Estos cultivos fueron positivos por PCR para el gen 16S ribosomal del genero Leptospira y luego se les realizo la tecnica Multi Loci VNTR (Variable Number Tandem Repeat) Analysis, para intentar identificar el serovar infectante. Se continuan con los cultivos positivos para intentar lograr aislamiento puro. Tambien se remitio al Instituto de Higiene muestras de sangre de las vacas que abortaron para analisis por la tecnica serologica de MAT para Leptospira. Los resultados de MAT de las vacas que abortaron no dieron reaccion. Se remitieron las mismas muestras de organos fetales al Departamento de Patologia de la Division de Laboratorios Veterinarios (DILAVE, Miguel C. Rubino - Laboratorio Regional Este) para analisis por histopatologia, donde se observaron lesiones de hemolisis intravascular compatibles con leptospirosis aguda fetal. Los signos clinicos observados a campo y el diagnostico macroscopico de las necropsias, junto con los resultados de laboratorio, sugieren que los abortos se debieron a infeccion por Leptospira spp. Se recomendo considerar el tratamiento con oxitetraciclina 20% larga accion a las vacas, y luego vacunacion preventiva con vacunas que contengan suspension inactivada de los serovares de Leptospira mas frecuentemente reactivos en MAT, entre ellos serovar Pomona y serovar Hardjo bovis.

Introducción: El síndrome urémico hemolítico (SUH) es una enfermedad de severidad variable que afecta sobre todo a niños menores de 5 años. Está definido por la tríada anemia hemolítica microangiopática, trombocitopenia e insuficiencia renal aguda. La mayoría de los casos aparecen luego de un episodio de diarrea aguda, causado por cepas de Escherichia coli productoras de toxina Shiga (STEC). Objetivo: Establecer las características de las cepas STEC recuperadas de niños con SUH, e informar sobre algunos aspectos clínicos y características epidemiológicas de estos casos. Materiales y métodos: Se realizó un estudio descriptivo que incluyó niños con SUH. La detección de las cepas STEC se realizó por PCR a partir de cultivos de materias fecales. En cada cepa se estableció el genotipo, serotipo y perfil de susceptibilidad a los antibióticos. Resultados: Se estudiaron 43 niños con SUH. Los casos ocurrieron predominantemente en los meses cálidos, afectando niños provenientes de hogares ubicados fuera de la capital y con cobertura privada de salud. La mayoría presentaban el antecedente de diarrea con sangre y 70% habían recibido antibióticos antes de obtener las muestras. En 7 niños se recuperaron 8 cepas STEC; 7 correspondieron a serogrupos no-O157. Todas portaban los genes eae y ehxA. Conclusiones: La mayoría de los casos ocurren en meses cálidos, en niños que cursaron diarrea con sangre, provenientes de hogares ubicados fuera de la ciudad capital. Los cultivos STEC no-O157 fueron los más prevalentes.

Infectious diarrhea, a common disease of children, deserves permanent monitoring in all social groups. To know the etiology and clinical manifestations of acute diarrhea in children up to 5 years of age from high socioeconomic level households, we conducted a descriptive, microbiological, and clinical study. Stools from 59 children with acute community-acquired diarrhea were examined, and their parents were interviewed concerning symptoms and signs. Rotavirus, adenovirus, and norovirus were detected by commercially available qualitative immunochromatographic lateral flow rapid tests. Salmonella, Campylobacter, Yersinia, and Shigella were investigated by standard bacteriological methods and diarrheagenic E. coli by PCR assays. We identified a potential enteric pathogen in 30 children. The most frequent causes of diarrhea were enteropathogenic E. coli (EPEC), viruses, Campylobacter, Salmonella, and Shiga-toxin-producing E. coli (STEC). Only 2 patients showed mixed infections. Our data suggest that children with viral or Campylobacter diarrhea were taken to the hospital earlier than those infected with EPEC. One child infected with STEC O26 developed “complete” HUS. The microbiological results highlight the importance of zoonotic bacteria such as atypical EPEC, Campylobacter, STEC, and Salmonella as pathogens associated with acute diarrhea in these children. The findings also reinforce our previous communications about the regional importance of non-O157 STEC strains in severe infant food-borne diseases.

Group B Streptococcus (GBS) is the leading cause of neonatal sepsis in the developed world. Little is known about the epidemiology and microbiological characteristics of the involved strains in the developing countries, where the majority of deaths from neonatal infections occur. The goals of this study were to assess the prevalence of recto-vaginal colonization with Group B Streptococcus (GBS) in pregnant women going into labor; to determine the capsular serotype of the recovered strains; and evaluate the performance of a commercial qualitative polymerase chain reaction (PCR) assay as a screening test. Between April and November 2012 we studied 87 pregnant women who delivered at the ‘Dr. Manuel Quintela University Hospital’. Recto-vaginal samples were processed by standard microbiological procedures as well as commercial PCR assay for GBS direct detection. Antimicrobial susceptibility tests on the recovered GBS strains were performed by disk-diffusion to penicillin, erythromycin and clindamycin. GBS isolates were serotyped by a previously described PCR procedure which identifies the following serotypes: Ia, Ib, II, III, IV, V, VI, VII and VIII. We recovered GBS in 9 out of 87 women (10.3%; 95% CI: 3.9-16.7). All the recovered GBS were susceptible to the antibiotics tested. The serotype distribution was as follows: serotype III, 3 isolates; serotypes Ia, Ib, IV and V, one isolate of each. The performance values of the commercial PCR assay applied directly to samples were: sensitivity 100%, specificity 97%, positive predictive value 82%, and negative predictive value 100%. If we take all PCR results as true positives, the performance of this PCR assay would be even better than standard culture method. In this case, the of GBS carriage in this population up to 13.2%. ready minutes, PCR assay requires the use of sophisticated laboratory equipment and does not allow the determination of the antimicrobial susceptibility pattern or the determination of the capsular serotype of the involved strains.

Introducción: la leptospirosis es una enfermedad febril, aguda, que presenta manifestaciones clínicas variadas. Esto dificulta o retarda el diagnóstico clínico, por lo cual es útil disponer de métodos de laboratorio adecuados para orientar el manejo inicial de estos pacientes. Objetivo: evaluar un procedimiento de inmunofluorescencia para detectar IgM (IF-IgM) de elaboración propia aplicado al diagnóstico temprano de leptospirosis. Material y método: se analizaron por IF-IgM y microaglutinación (MAT) (tomada como estándar de referencia) sueros obtenidos de pacientes con sospecha clínica de leptospirosis. La sensibilidad y especificidad de la IF-IgM versus MAT se establecieron utilizando una tabla de doble entrada. La concordancia entre dos observadores se determinó por el test Kappa. Resultados: de 161 muestras precoces analizadas, 97 sueros correspondieron a pacientes con infección aguda confirmada por MAT y 64 sin infección. La sensibilidad y especificidad de la IF-IgM con sueros de fase aguda fueron 79% y 100%, respectivamente. El índice Kappa fue 1. Conclusiones: la IF-IgM aparece como una herramienta útil para el diagnóstico temprano de pacientes con leptospirosis. No requiere el manejo de bacterias viables, puede realizarse en laboratorios que cuenten con microscopio de luz ultravioleta, se necesita una sola muestra de suero y el resultado está listo en tres a cuatro horas. En cuanto a las desventajas, no identifica los serovares involucrados y un resultado negativo no descarta la infección. Teniendo en cuenta esto último es obligatorio analizar por MAT una segunda muestra de suero obtenida a los 10-20 días de la primera para descartarla o confirmarla.

Introduction: leptospirosis is a severe febrile disease, with a variety of clinical presentations. This results in the delay of clinical diagnosis, or in difficulties achieving it, so having the appropriate laboratory tests may deem useful to guide the initial care of these patients.Objective: to evaluate a self-made immunofluorescence technique for the detection of IgM antibodies (IF-IgM) in the early diagnosis of leptospirosis.Method: serum samples obtained from patients with a clinical suspicion of leptospirosis were analysed by IF-IgM antibodies and the microagglutination test (MAT). Sensitivity and specificity of IF-IgM versus MAT were determined using a double entry table. Agreement between two observers was determined by the Kappa test.Results: out of one hundred and sixty one early samples analysed, 97 serum samples corresponded to patients with a confirmed acute infection by MAT and 64 evidenced no infection. Sensitivity and specificity of IF-IgM assays in the acute phase were 79% and 100% respectively. The Kappa value was 1.Conclusions: IF-IgM seems to be a useful tool for the early diagnosis of patients with leptospirosis. It does not need viable bacteria to be handled; it may be applied in laboratories equipped with ultraviolet light microscopes, a single serum sample is needed and the result is seen three to four hours later. As to its disadvantages, it fails to identify the involved serovars and a negative result does not discard infection. Bearing the latter into account, the MAT test is mandatory in a second serum sample obtained 10-20 days after the first one, to either discard or confirm the disease.

Hemolytic uremic syndrome (HUS) is a disorder characterized by the presence of the classic triad: microangiopathic hemolytic anemia, thrombocytopenia and acute renal injury. HUS without acute renal failure can be confused with other hematologic diseases. An infantile HUS caused by a Shiga-toxin-producing Escherichia coli (STEC) O145 strain carrying genotype stx2, ehxA, eae subtype β1 is herein reported. The infant did not require dialysis during the acute stage of HUS, evolved favorably, maintained normal blood pressure and normal renal function and had no recurrence until the last control. This could be due to several factors, such as the characteristics of infecting STEC strain and a reduction in host susceptibility to renal injury. This report highlights the regional participation of non-O157 STEC in childhood diseases and the importance of performing active surveillance for all forms of HUS.

INTRODUCTION:Assays based on DNA amplification can provide information that contributes to the initial management of patients with leptospirosis. However, these have not been adopted in Uruguay. Our aim was to evaluate the performance of the lipL32 real-time PCR (qPCR) for diagnosis of leptospirosis.METHODOLOGY:We analyzed by microscopic agglutination test (MAT) and lipL32 qPCR serum samples from 183 patients with suspected leptospirosis. To establish the analytical sensitivity of the qPCR, experimentally spiked samples with known amounts of Leptospira interrogans were analyzed.RESULTS:The analytical sensitivity of the qPCR was 102 leptospires/mL. In 98 patients MAT results were negative meanwhile 85 showed positive reactions, revealing acute infections. Twenty six acute-phase sera of these 85 patients showed a positive signal by qPCR (diagnostic sensitivity 30%). In these patients the average time between onset of symptoms and collection of the first sample was 8 days. In patients with negative results for qPCR and positive MAT results (n=59) the average interval between onset of symptoms and collection of the first sample was 13 days. The qPCR did not yield false positive results.CONCLUSIONS:The qPCR had a lower diagnostic sensitivity than MAT and a higher cost. However, it allowed to make an early diagnosis in 26 patients. In patients with confirmed acute infections and negative results by qPCR, more than 8 days had elapsed between the onset of the illness and extraction of the first serum sample. Our data support that the qPCR from sera have clinical utility within the first week of illness.