Diarreia em bezerros no sul do Rio Grande do Sul em um período de 34 anos / Diarrhea in calves in Southern Rio Grande do Sul in a period of 34 years

The objective of this work was to conduct a retrospective study of causes of diarrhea in calves in southern Rio Grande do Sul between 1980 and 2014. All necropsy protocols and materials received in the Regional Diagnostic Laboratory of the Veterinary School of the Federal University of Pelotas were reviewed. Ninety-four cases of calves with diarrhea were diagnosed, of these, 44.7% were caused by parasitic infections and 34.0% by bacterial infections. Parasites as cause of diarrhea was the most important diagnostic in southern Rio Grande do Sul and affected calves from three to 12 months of age. The occurrence of diarrhea in animals even infants may be associated with environmental factors and the form of management that these animals are kept. Bacterial diseases are also important causes of diarrhea in calves up to three months of age in the region.

O objetivo deste trabalho foi descrever os dados de um estudo retrospectivo nos registros de 34 anos atividade de um laboratório de diagnóstico sobre as causas de diarreia em bezerros na região sul do Rio Grande do Sul. Foram revisados os protocolos de necropsia e materiais desta espécie encaminhados ao Laboratório Regional de Diagnóstico da Faculdade de Veterinária da Universidade Federal de Pelotas. Foram diagnosticados 94 casos de bezerros com diarreia, destes, 44,7% foram de causas parasitárias e 34,0% de causas bacterianas. Diarreia de causa parasitária foi a mais importante na região sul do Rio Grande do Sul e afetou bezerros de três a 12 meses de idade. A ocorrência de diarreia em animais mesmo lactentes pode estar associada a fatores ambientais e a forma de manejo no qual esses animais são mantidos. As enfermidades bacterianas foram, também, importantes causas de diarreia em bezerros de até três meses de idade na região.

Giardia co-infection promotes the secretion of antimicrobial peptides beta-defensin 2 and trefoil factor 3 and attenuates attaching and effacing bacteria-induced intestinal disease.

Our understanding of polymicrobial gastrointestinal infections and their effects on host biology remains incompletely understood. Giardia duodenalis is an ubiquitous intestinal protozoan parasite infecting animals and humans. Concomitant infections with Giardia and other gastrointestinal pathogens commonly occur. In countries with poor sanitation, Giardia infection has been associated with decreased incidence of diarrheal disease and fever, and reduced serum inflammatory markers release, via mechanisms that remain obscure. This study analyzed Giardia spp. co-infections with attaching and effacing (A/E) pathogens, and assessed whether and how the presence of Giardia modulates host responses to A/E enteropathogens, and alters intestinal disease outcome. In mice infected with the A/E pathogen Citrobacter rodentium, co-infection with Giardia muris significantly attenuated weight loss, macro- and microscopic signs of colitis, bacterial colonization and translocation, while concurrently enhancing the production and secretion of antimicrobial peptides (AMPs) mouse ß-defensin 3 and trefoil factor 3 (TFF3). Co-infection of human intestinal epithelial cells (Caco-2) monolayers with G. duodenalis trophozoites and enteropathogenic Escherichia coli (EPEC) enhanced the production of the AMPs human ß-defensin 2 (HBD-2) and TFF3; this effect was inhibited with treatment of G. duodenalis with cysteine protease inhibitors. Collectively, these results suggest that Giardia infections are capable of reducing enteropathogen-induced colitis while increasing production of host AMPs. Additional studies also demonstrated that Giardia was able to directly inhibit the growth of pathogenic bacteria. These results reveal novel mechanisms whereby Giardia may protect against gastrointestinal disease induced by a co-infecting A/E enteropathogen. Our findings shed new light on how microbial-microbial interactions in the gut may protect a host during concomitant infections.

Dissemination of Strongyloides stercoralis as an immune restoration phenomenon in an HIV-1-infected man on antiretroviral therapy.

We present a case of Strongyloides stercoralis infection in an HIV-infected man, resulting in Escherichia coli meningitis after initiation of antiretroviral therapy. Recent evidence from studies of strongyloides development supports the concept that strongyloides dissemination in this case is an example of an immune reconstitution inflammatory syndrome.

Influence of colostrum deprivation and concurrent Cryptosporidium parvum infection on the colonization and persistence of Escherichia coli O157 : H7 in young lambs.

Escherichia coli O157 : H7 and Cryptosporidium parvum infections of man have been associated with direct contact with small ruminants. Colostrum protects neonates against gastrointestinal pathogens, and orphan lambs, which are common on petting farms, may be deprived of this protection. In a recent study, it was demonstrated that high shedding of E. coli O157 : H7 by an 8-week-old goat kid was associated with coincidental C. parvum infection. Furthermore, both pathogens were co-located in the distal gastrointestinal tract. It was hypothesized that colostrum deprivation and pre-infection with C. parvum predisposed young ruminants to colonization and increased shedding of E. coli O157 : H7. To test this, 21 lambs 5 weeks of age were divided into four groups as follows: (A) colostrum-deprived and inoculated with E. coli O157 : H7, (B) colostrum-deprived and inoculated with C. parvum and then E. coli O157 : H7, (C) conventionally reared and inoculated with E. coli O157 : H7, (D) conventionally reared and inoculated with C. parvum and then E. coli O157 : H7. C. parvum was detected between 8 and 12 days post-inoculation in most of the infected lambs. At 24 h post-inoculation with E. coli O157 : H7, all lambs were shedding between 5 x 10(4) and 5 x 10(7) c.f.u. E. coli O157 : H7 per gram of faeces. E. coli O157 : H7 was shed in higher numbers in the groups pre-inoculated with C. parvum, whether conventionally reared or colostrum-deprived. Interestingly, for the colostrum-deprived lambs on day 3, a significant difference in shedding of E. coli O157 : H7 was observed (P = 0.038), with the lambs inoculated with E. coli alone yielding higher counts than those pre-inoculated with C. parvum. From day 15 onwards, shedding of E. coli O157 : H7 was highest from the colostrum-deprived C. parvum-infected lambs, then (in descending order of shedding) the colostrum-deprived lambs, the conventionally reared lambs infected with C. parvum, and the conventionally reared animals. In total, four animals were euthanized, two at 24 h and two at 96 h post inoculation with E. coli O157 : H7 (two conventionally reared and two colostrum-deprived). All animals euthanized were from groups pre-inoculated with C. parvum prior to challenge with E. coli O157 : H7. On examination of tissues, in three of the four animals examined, multifocal attaching and effacing lesions were observed in the caecum, colon, rectum and at the recto-anal junction, and were confirmed by immunohistochemistry to be associated with E. coli O157 : H7.

Role of cysteine proteinase of Entamoeba histolytica in target cell death.

The bacterial flora of the intestine plays an important role in the virulence caused by Entamoeba histolytica. Cysteine proteinase (CP), an amoebic virulence factor, plays a major role in host cell destruction. The mechanism of increased virulence following bacterial co-association is not understood. We studied CP of E. histolytica HM1:IMSS which was co-associated with Escherichia coli K12 strain pre-incubated with GalNAc or CP specific inhibitor E 64. Co-association of E. histolytica with bacteria enhanced CP activity 3-6-fold as assessed by azocasein assay and substrate gel electrophoresis showed bands at molecular weights of 28, 35 and 56 kDa. Northern and Western blot analysis showed increase in ehcp2 and ehcp5 gene expression. Trophozoites co-associated with E. coli showed greater cytotoxicity of BHK cells by a 51Cr release assay than trophozoites that had not been co-associated; this enhancement was abolished by E-64 treatment. The killing of BHK 21 targets by E. histolytica was characterized by DNA laddering which was not inhibited with E-64. GalNAc pre-incubation of trophozoites reduced cytotoxicity and DNA laddering, while E. coli co-associated E. histolytica showed smearing with faint laddering of BHK implicating both necrosis and apoptosis. Hence, bacterial co-association increases CP activity and CP gene expression and contributes to the necrosis of the target cell.

Diarrhoeal diseases surveillance in Trinidad and Tobago

Between July 28th and December 28th, 1991, 2,935 cases of diarrhoeal illness were reported to the National Surveillance Unit of the Ministry of Health, in response to the intensified surveillance activities of the Cholera Preparedness Programme. The cases notified included 1,656 children less than five years of age (56.4 percent) and 1,279 persons over age five. The average number of reported cases per week was 133 with a range of 62-202 cases. A review of certain laboratory indicators was recently undertaken in order to assess the ease with which cholera would spread locally if introduced into Trinidad and Tobago. This analysis is based on data produced by the Trinidad Public Health Laboratory (AU)

[Mixed coli-rotavirus and Cryptosporidium infection in newborn piglets]. / Smesena koli-rotavirusna infektsiia i kriptosporidiina invaziia pri novorodeni praseta.

Complex morphologic, parasitologic, virologic, and bacteriologic studies on pigs and fecal samples from pigs were carried out on a farm where an enteritis infection in newborn pigs was recorded. A mixed coli-rotavirus and cryptosporidium infection was established in 10--20-day-old pigs of the Camborough hybrid with a clinically manifested enteritis syndrome. Morphologically, the cryptosporidium component of the infection substantiated atrophic and dystrophic changes in the intestinal epithelium. Developmental forms of the parasite were also found in the border wall of the enterocytes.

[Ultramicroscopic study of the colonic mucosa infected by E. histolytica]. / Estudio ultramicroscópico de la invasión de la mucosa del colon por E. histolytica

In eight guinea pigs, trophozoites of E. histolytica HM-2 IMSS strain grown in plurixenic conditions were inoculated in their cecum. Two died two days after inoculation; the remaining si- were sacrificed six days afterwards. Tissue samples were obtained from amebic lesions and nearby areas. At ultramicroscopic level it was observed that epithelial cells in contact with the parasite had short and/or scanty microvilli, swollen mitochondria, ER dilatation and absence of the terminal bar. When trophozoite was within the epithelium, cells in contact with it were destroyed; basement membrane was elongated before it was broken up by the parasite. In the lamina propria trophozoites were found close to glands, blood capillaries and in contact with macrophages, lymphocytes, and most cells. No polymorphonuclear cells were identified in all samples studied. Capillaries were congestive, lacking polymorphonuclear cells. It was postulated that probably initial colonic mucosa lesion in amebiasis depends solely upon parasite action.