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.

Leptospira spp. are delicate bacteria that cannot be studied by usual microbiological methods. They cause leptospirosis, a zoonotic disease transmitted to humans through infected urine of wild or domestic animals. We studied the incidence of this disease in the Uruguayan population, its epidemiologic and clinical features, and compared diagnostic techniques. After examining 6,778 suspect cases, we estimated that about 15 infections/100,000 inhabitants occurred yearly, affecting mainly young male rural workers. Awareness about leptospirosis has grown among health professionals, and its lethality has consequently decreased. Bovine infections were probably the principal source of human disease. Rainfall volumes and floods were major factors of varying incidence. Most patients had fever, asthenia, myalgias or cephalalgia, with at least one additional abnormal clinical feature. 30-40% of confirmed cases presented abdominal signs and symptoms, conjunctival suffusion and altered renal or urinary function. Jaundice was more frequent in patients aged > 40 years. Clinical infections followed an acute pattern and their usual outcome was complete recovery. Laboratory diagnosis was based on indirect micro-agglutination standard technique (MAT). Second serum samples were difficult to obtain, often impairing completion of diagnosis. Immunofluorescence was useful as a screening test and for early detection of probable infections.

CA-MRSA isolates produced a wide spectrum of invasive diseases in a public paediatric hospital between 2003 and 2006. Microbiologic characterization suggests the spread of an adapted CA-MRSA clone lacking erm genes.

We analyzed 90 nonduplicates community-associated methicillin-resistant S. aureus (CA-MRSA) strains isolated from skin and soft-tissue infections. All strains were mecA positive. Twenty-four of the 90 strains showed inducible macrolide-lincosamide-streptogramin B resistance. All strains produced α-toxin; 96% and 100% of them displayed positive results for lukS-F and cna genes, respectively. Eigthy-five strains expressed capsular polysaccharide serotype 8. Six different pulsotypes were discriminated by pulsed-field gel electrophoresis (PFGE) and three predominant groups of CA-MRSA strains (1, 2, and 4) were identified, in agreement with phenotypic and genotypic characteristics. Strains of group 1 (pulsotype A, CP8+, and Panton-Valentine leukocidin (PVL)+) were the most frequently recovered and exhibited a PFGE band pattern identical to other CA-MRSA strains previously isolated in Uruguay and Brazil. Three years after the first local CA-MRSA report, these strains are still producing skin and soft-tissue infections demonstrating the stability over time of this community-associated emerging pathogen.

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.