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C Maddox

Publications and source records attributed to C Maddox.

6 recordsLinked to original sources
PubMed1998

Examination for heat-labile, heat-stable, and Shiga-like toxins and for the eaeA gene in Escherichia coli isolates obtained from dogs dying with diarrhea: 122 cases (1992-1996).

OBJECTIVE: To examine Escherichia coli isolates obtained from dogs dying with diarrhea for heat-labile, heat-stable, and Shiga-like toxins and for the eaeA gene, which is associated with attaching and effacing lesions. DESIGN: Retrospective study. ANIMALS: 122 dogs. PROCEDURE: E coli isolates were tested by means of dot-blot hybridization of DNA extracts of cultured bacteria. Medical records of dogs from which E coli isolates with virulence genes had been isolated were examined, and histologic findings and evidence of intercurrent bacterial and viral infections were recorded. RESULTS: None of the E coli isolates obtained from these dogs produced heat-labile, heat-stable, or Shiga-like toxins; however, E coli isolates from 44 of 122 dogs were found to have the eaeA gene. Histologically, multifocal bacterial adherence to the epithelium and epithelial necrosis and detachment were seen in colonic specimens from 20 of 44 (45%) dogs. Escherichia coli was the sole pathogen identified in 15 of 44 (34%) dogs. Intercurrent pathogens, including canine parvovirus (n = 19), Clostridium perfringens (8), rotavirus (5), hookworms (3), coccidia (3), and Salmonella agona (1), were identified in the remaining 29 (66%) dogs. CLINICAL IMPLICATIONS: Attaching and effacing E coli can be a primary or secondary pathogen in dogs with diarrhea. Antibiotic treatment is indicated in dogs with diarrhea because of the possibility that it is primarily bacterial in origin and because, even if it is primarily viral in origin, there may be secondary bacterial infection.

Adhesins, Bacterial↗
PubMed1994

Pathogenicity of a bovine attaching effacing Escherichia coli isolate lacking Shiga-like toxins.

Escherichia coli isolate 7996-90, obtained from a calf with diarrhea, had negative results of tests for K-88, K-99, 987P, F41, CS31A, F1845, F165 or E. coli adherence factor adhesins and had negative results of tests for the toxins heat-labile, heat-stable A, heat-stable B, Shiga-like toxin (SLT)-I or SLT-II. Strain 7996-90 had localized adherence to HEp-2 cells, caused actin rearrangement in host cells to which it adhered, hybridized with the eaeA probe, and produced the 94-kd outer membrane protein associated with attaching effacing lesions. This isolate caused attaching effacing lesions in Caco-2 cell polar monolayers, rabbit intestinal loops, and the intestines of gnotobiotic pigs. The isolate belongs to serotype O26: NM and is considered a class-II attaching effacing enteropathogenic E coli. Until recent addition of more sensitive assays at veterinary diagnostic laboratories, isolates such as 7996-90 were not readily recognized as pathogens because they failed to fit into the enterohemorrhagic E coli group, members of which, be definition, produce SLT. The assays described can facilitate diagnosis of attaching effacing E coli infection when histologic evaluation is hampered by autolysis.

Animals↗
PubMed1992

Pneumonia associated with Salmonella choleraesuis infection in swine: 99 cases (1987-1990).

Salmonella choleraesuis was isolated in pure or mixed bacterial cultures from 153 swine necropsied between Jan 1, 1987 and Dec 31, 1990. Pneumonia was seen in 99 of 109 swine from which this bacterium was isolated in the absence of other pathogenic bacteria. Pneumonia was seen more frequently than hepatitis, splenomegaly, or colitis. Pleuropneumonia that was grossly indistinguishable from the pleuropneumonia associated with Actinobacillus pleuropneumoniae was seen in 29 of 99 swine from which S choleraesuis was the only bacterium isolated.

Animals↗