(1/24) Human infection with M- strain of Brucella canis.
The less mucoid strain of Brucella canis or M- strain is used for the serologic diagnosis of canine brucellosis. While this strain is avirulent in dogs, we report the case of clinical brucellosis that developed in a laboratory worker a few days after handling live M- cells for antigen production. (+info)
(2/24) Diagnosis of human brucellosis caused by Brucella canis.
The transmission of Brucella canis to man commonly occurs through contact with infected dogs or their secretions, or through direct laboratory exposure. The disease is underdiagnosed due to a general lack of serological testing facilities and misconceptions concerning its prevalence. This report shows the potential use of an indirect ELISA (IELISA) for the diagnosis of human brucellosis caused by B. canis in a population of patients negative by smooth-Brucella antigen tests but positive by rapid slide agglutination test (RSAT). One hundred and ten sera from asymptomatic people found negative by tests using smooth Brucella abortus antigen and by RSAT showed an IELISA specificity of 100 % when a cut-off value of 27 % positivity (%P) was selected. For 17 sera from patients with positive B. canis culture or in close contact with culture-positive dogs, the IELISA sensitivity was 100 % with the same cut-off value. The positive patients presented clinical symptoms similar to brucellosis caused by other species of Brucella and some of them received antibiotic treatment and made good progress. Using this cut-off value, we studied 35 patients with negative blood cultures but positive RSATs, and IELISA detected 18 as positive; of the 17 IELISA-negative, two were RSAT-positive at dilution 1 : 2 and 15 were weakly positive with pure serum. These samples were probably from patients at an early stage of infection or indicate false-positive results. No cross-reaction was observed among the sera from nine cases with a diagnosis other than brucellosis, but cross-reactivity was evident in sera from patients infected with smooth-Brucella species. Since routine brucellosis diagnosis does not include B. canis investigation, infection with this species may be more widespread than is currently suspected. The RSAT could be a suitable screening test for the diagnosis of B. canis human brucellosis, and a supplementary technique, such as IELISA, performed on all positive RSAT samples that were negative by B. abortus antigen could ensure diagnostic specificity and confirm the diagnosis. (+info)
(3/24) Unusual clinical presentation of brucellosis caused by Brucella canis.
Brucella canis is considered a rare cause of human brucellosis. The clinical importance of this infection may have been underestimated so far because of difficulties with presumptive diagnosis. The case described here presented symptoms compatible with brucellosis but the routine tests using Brucella abortus antigen were negative. The infection would have remained undiagnosed if culture had not been positive. This case illustrates the potential for a favourable outcome in Brucella canis diagnosis and supports recommendations for the use of B. canis serology. The infection should be suspected in patients with compatible symptoms and negative serology for B. abortus antigen. (+info)
(4/24) Detection of Brucella canis and Leptospira interrogans in canine semen by multiplex nested PCR.
Brucella canis and Leptospira interrogans are pathogenic bacteria that cause brucellosis and leptospirosis in dogs around the world. Both diseases can be diagnosed serologically, but the direct detection of these organisms in canine semen is needed when it is used for artificial reproduction. We have been attempting the artificial reproduction of guide dogs for greater breeding efficiency and for this purpose have developed a multiplex nested PCR technique for the detection of B. canis and L. interrogans in the semen and cryoprotective agent (CPA). Our results demonstrated the high sensitivity and simplicity of this technique in the detection of these organisms in canine semen and that will be useful in routine diagnosis. Since they have been found to stay alive in canine semen and CPA up to 48 hr, canine semen for breeding purposes should be checked for contamination by the PCR assay. (+info)
(5/24) Investigation of the spread of Brucella canis via the U.S. interstate dog trade.
OBJECTIVES: The aim of this study was to illustrate and help address a growing need for regulatory or molecular tools to track and control the spread of canine brucellosis. Our study objectives were to first characterize Brucella canis outbreaks in Wisconsin kennels in the context of the dog trade in the USA, and then to identify a molecular technique that may be useful for strain differentiation of B. canis isolates. METHODS: Wisconsin Veterinary Diagnostic Laboratory (WVDL) B. canis serology data from 1995 to 2005 were reviewed, three canine brucellosis outbreaks in Wisconsin dog kennels were investigated, and eight B. canis isolates recovered from Wisconsin outbreaks and kennels in Missouri and Arkansas and four isolates received from outside sources were subjected to ribotyping, pulsed-field gel electrophoresis (PFGE), outer membrane protein analysis (OMPA), and cellular fatty acid profiling (CFAP). RESULTS: WVDL has received increasing numbers of B. canis positive samples from Wisconsin kennels, and Wisconsin outbreaks are associated with the interstate dog trade. All of the B. canis isolates we examined were genetically homogenous and as such could not be differentiated by ribotyping, PFGE and OMPA. However, dendrogram analysis of CFAP divided the isolates into two groups, indicating that CFAP methyl ester analysis has discriminatory power. CONCLUSIONS: CFAP methyl ester analysis has promise as a tool for epidemiological tracing of B. canis outbreaks and will be useful in comparison studies as isolation of B. canis continues to expand globally. (+info)
(6/24) A rapid agglutination assay for canine brucellosis using antigen coated beads.
Brucella canis is the causative agent of canine brucellosis and facultative intracellular pathogen. The diagnosis of canine brucellosis is based on bacteriological examination and serological methods including agglutination and gel diffusion tests. In this study, crude antigens were extracted from B. canis using hot saline, coated on to latex beads and their usefulness in the serological diagnosis of canine brucellosis was examined. Mixing the antigen coated latex beads with the sera of dogs infected with B. canis produced clear agglutination, but this was not so for B. canis free dog sera. N-terminal amino acid sequence analysis of the crude hot saline extracts, showed that they contained copper-zinc superoxide dismutase, ribose ABC transporter and hypothetical protein of Brucella as antigens. A serological survey of canine serum samples conducted by means of an agglutination test using the antigen coated latex beads, showed that this method was more specific than the tube agglutination test using whole bacterial cell antigens. Although these results suggest that our method in which crude hot saline extracted antigens are coated on to latex beads would be useful in the serological diagnosis of canine brucellosis, we need further investigation using more serum samples to confirm the usefulness of our method. (+info)
(7/24) Evaluation of immunochromatographic assay for serodiagnosis of Brucella canis.
Canine brucellosis is a contagious disease with venereal and oral modes of transmission that produces late abortion in females, epididymides and prostates in males. Diagnosis is difficult because of unstable serum antibody titers that vary from individual to individual as well as between different methods used for their detection. The objective of this work was to evaluate the clinical utility of the immunochromatographic assay (ICA) for serodiagnosis of dogs suspected of having brucellosis, and results were compared with those obtained for hemoculture (HC) and the rapid screening agglutination with 2-mercaptoethanol (2-ME RSAT). The all experimentally infected dogs were positive in ICA, HC and 2-ME RSAT from 5 weeks, 7 weeks, and 3 weeks after infection, respectively. Also, among dogs selected from 10 different breed kennels occurred brucellosis, 24.8%, 39.5% and 39.1% of dogs tested were detected as positive with HC, 2-ME RSAT and ICA, respectively. The kappa value between 2-ME RSAT and ICA was 0.89. The results of this study showed that sensitivity and specificity of the ICA are comparable with those obtained using conventional serological and bacteriological test for brucellosis. In conclusion, the ICA kit provides a handy and accurate tool for the rapid serodiagnosis of canine brucellosis. (+info)
(8/24) Evaluation of a microplate agglutination test (MAT) for serological diagnosis of canine brucellosis.
A microplate agglutination test (MAT) was compared with the tube agglutinin test (TAT), a standard test for the diagnosis of Brucella canis, in terms of the sensitivity and specificity. The results showed that MAT was more sensitive, simpler to perform and easier to read the results than TAT. On top of that the MAT allows us to handle a larger number of samples at once. Using this method we conducted sero-surveillance of the prevalence of B. canis in dogs kept in an Animal Shelter located in Kanagawa Prefecture. Twelve of 485 (2.5%) showed seropositive against B. canis. These results indicate that B. canis infection in dogs is still occurring in Japan. (+info)