RESUMEN

A 65-year-old male patient presented with fever, fast atrial fibrillation and frank haematuria on return to Ireland from travel in East Africa. He had a systolic murmur leading to a clinical suspicion of endocarditis. He had no specific clinical features of diphtheria. Blood cultures were taken and empiric therapy commenced with benzylpenicillin, vancomycin and gentamicin. Corynebacterium diphtheriae was detected on blood culture. The isolate was submitted to a reference laboratory for evaluation of toxigenicity. While initially there was concern regarding the possibility of myocarditis, a clinical decision was made not to administer diphtheria antitoxin in the absence of clinical features of respiratory diphtheria, in the presence of invasive infection and with presumptive previous immunisation. There is no specific guidance on the role of antitoxin in this setting. The issue is not generally addressed in previous reports of C. diphtheriae blood stream infection.

Asunto(s)

Infecciones por Corynebacterium/sangre , Corynebacterium diphtheriae/aislamiento & purificación , Administración Intravenosa , Anciano , Antibacterianos/administración & dosificación , Ceftriaxona/administración & dosificación , Infecciones por Corynebacterium/tratamiento farmacológico , Infecciones por Corynebacterium/microbiología , Antitoxina Diftérica/uso terapéutico , Úlcera del Pie/complicaciones , Humanos , Masculino , Insuficiencia de la Válvula Mitral/complicaciones , Insuficiencia de la Válvula Mitral/microbiología , Insuficiencia de la Válvula Mitral/cirugía

RESUMEN

This study aimed to identify clinical or microbiological factors affecting the clinical relevance of Corynebacterium striatum isolated from blood cultures. A total of 64 isolates from 51 patients identified as C. striatum by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were assessed. More than two blood cultures were positive in 25 (48.1%) patients. Diabetes, solid tumor, and a history of previous exposure to antibiotics were more common in patients with multiple positive blood cultures. Charlson comorbidity scores were also higher, and more isolates were recovered after 48 hours of hospital stay in patients with multiple positive blood cultures. Strains recovered from patients with multiple positive blood cultures produced significantly more biofilm. Based on multilocus sequence typing (MLST), sequence type (ST) 20 (31.3%) was the most dominant, followed by ST2 (20.3%) and ST23 (10.9%). There was no relationship between the number of positive blood culture sets and sequence typing. In multivariate analyses, Carlson comorbidity score (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.09-3.36; P = 0.03) and biofilm formation were associated with multiple positive blood cultures (OR, 17.43; 95% CI, 3.71-81.91; P = 0.03). This study provides evidence that the biofilm phenotype could contribute to determining the clinical significance of C. striatum in patients with severe underlying conditions. The predominance of certain STs suggests the relatedness of C. striatum infection and the nosocomial environment.

Asunto(s)

Cultivo de Sangre/métodos , Infecciones por Corynebacterium/sangre , Corynebacterium/aislamiento & purificación , Anciano , Biopelículas/crecimiento & desarrollo , Corynebacterium/fisiología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad

RESUMEN

Haptoglobin (Hp) and Serum Amyloid A (SAA) are a group of blood proteins whose concentrations in animals can be influenced by infection, inflammation, surgical trauma or stress. Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), and Mycolic acid is a virulent factor extracted from C. pseudotuberculosis. There is a dearth of sufficient evidence on the clinical implication of MAs on the responses of Hp and SAA in goats. Therefore, this study was conducted to evaluate the potential effects of Mycolic acid (MAs) and C. pseudotuberculosis on the responses of Hp and SAA in female goats. A total of 12 healthy female goats was divided into three groups; A, B and C each comprising of 4 goats and managed for a period of three months. Group (A) was inoculated with 2 mL of sterile phosphate buffered saline (as a negative control group) intradermally, while group (B) and (C) were inoculated intradermally with 2 ml each of mycolic acid and 1  × 109 cfu of active C. pseudotuberculosis respectively. The result of the study showed that the Hp concentration in goats inoculated with C. pseudotuberculosis was significantly increased up to 7-fold (1.17 ±â€¯0.17 ng/L) while MAs showed a 3-fold increased (0.83 ±â€¯0.01 ng/L) compared with the control. Whereas SAA concentration in C. pseudotuberculosis and MAs groups showed a significant 3-fold (17.85 ±â€¯0.91 pg/mL) and 2-fold (10.97 ±â€¯0.71 pg/mL) increased compared with the control. This study concludes that inoculation of C. pseudotuberculosis and MAs have significant effects on Hp and SAA levels, which indicates that MAs could have a role in the pathogenesis of caseous lymphadenitis.

Asunto(s)

Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/inmunología , Corynebacterium pseudotuberculosis/metabolismo , Haptoglobinas/metabolismo , Ácidos Micólicos/farmacología , Proteína Amiloide A Sérica/metabolismo , Animales , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/aislamiento & purificación , Femenino , Enfermedades de las Cabras/sangre , Cabras/sangre , Haptoglobinas/análisis , Linfadenitis/microbiología , Ácidos Micólicos/aislamiento & purificación , Proteína Amiloide A Sérica/análisis

Asunto(s)

Antibacterianos/administración & dosificación , Infecciones por Corynebacterium/tratamiento farmacológico , Corynebacterium/efectos de los fármacos , Daptomicina/administración & dosificación , Farmacorresistencia Bacteriana , Administración Intravenosa , Infecciones por Corynebacterium/sangre , Humanos , Masculino , Persona de Mediana Edad , Vancomicina/administración & dosificación

RESUMEN

BACKGROUND: Goat caseous lymphadenitis (CLA) is a chronic disease caused by Corynebacterium pseudotuberculosis. However, there is paucity of data about goat's acute phase response during the course of CLA. This study was conducted to investigate the response of acute phase proteins, mainly haptoglobin (Hp), serum amyloid A (SAA) and the negative acute phase response, especially albumin after an experimental challenge of C. pseudotuberculosis and phospholipase D (PLD) in Cross bred Boer goats. RESULTS: Serum Hp concentration in goats challenged with C. pseudotuberculosis (inoculated with 1x10(9) cfu subcutaneously) showed a significant increase, 5 fold in males (0.98 ± 0.12 mg/ml) and 3 fold in females (0.66 ± 0.12 mg/ml) compared to the control (0.2 ± 0.02 mg/ml). Challenge with PLD (1 ml/20 kg body weight intravenously) also showed significant increase, 4 fold in males and females (0.89 ± 0.11 mg/ml; 0.82 ± 0.12 mg/ml) respectively compared to the control (0.2 ± 0.02 mg/ml). Albumin concentration showed a significant decrease in both treated groups compared to the control. There were no significant changes in SAA concentration between challenged and control goats. CONCLUSIONS: There was a significant response by Hp to C. pseudotuberculosis infection and PLD challenge. This was supported by the early acute response in which Hp was detected before CLA lesions were developed. Therefore, it concluded that C. pseudotuberculosis and PLD can influence the level of acute phase proteins in goats.

Asunto(s)

Proteínas de Fase Aguda/metabolismo , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis , Cabras/sangre , Animales , Infecciones por Corynebacterium/sangre , Femenino , Haptoglobinas/metabolismo , Masculino , Fosfolipasa D/farmacología , Proteína Amiloide A Sérica/metabolismo

RESUMEN

Toxigenic Corynebacterium ulcerans is a zoonotic pathogen that produces diphtheria toxin and causes a diphtheria-like illness in humans. The organism is known to infect and circulate among dogs, which can then transmit it to humans. Furthermore, previous studies have found that C. ulcerans is carried by wild animals, including game animals. In the present study, we tested hunting and companion dogs for the presence of toxigenic C. ulcerans and succeeded in isolating the bacterium from a hunting dog. Moreover, several hunting dogs had serum diphtheria antitoxin titers that were higher than the titers required for protection in humans, suggesting a history of exposure to toxigenic Corynebacterium strains. Notably, ribotyping, pulsed-field gel electrophoresis and tox gene sequencing demonstrated that the isolate from the hunting dog clustered with previously characterized C. ulcerans strains isolated from wild animals, as opposed to groups of isolates from humans and companion dogs. Interestingly, the wild animal cluster also contains an isolate from an outdoor breeding dog, which could have formed a bridge between isolates from wild animals and those from companion dogs. The results presented herein provide insight into the mechanism by which the zoonotic pathogen C. ulcerans circulates among wild animals, hunting and companion dogs, and humans.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium/inmunología , Corynebacterium/aislamiento & purificación , Toxina Diftérica/inmunología , Enfermedades de los Perros/microbiología , Animales , Animales Salvajes/microbiología , Anticuerpos Antibacterianos/sangre , Chlorocebus aethiops , Corynebacterium/genética , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/inmunología , Infecciones por Corynebacterium/microbiología , Girasa de ADN/genética , Antitoxina Diftérica/sangre , Toxina Diftérica/genética , Toxina Diftérica/aislamiento & purificación , Enfermedades de los Perros/sangre , Enfermedades de los Perros/inmunología , Perros , Electroforesis en Gel de Campo Pulsado/métodos , Femenino , Humanos , Japón , Masculino , Células Vero , Zoonosis/inmunología , Zoonosis/microbiología

RESUMEN

The objective of this study was to evaluate the diagnostic performance of two ELISA tests applied to bulk tank milk (BTM) as the first part of a two-step test scheme for the surveillance of caprine arthritis encephalitis (CAE) and caseous lymphadenitis (CLA) infections in goats. The herd-level BTM tests were assessed by comparing them to the test results of individual serological samples. The potential for refining the cut-off levels for BTM tests used as surveillance tools in a population recently cleared of infection was also investigated. Data was gathered on serum (nCAE =9702 and nCLA=13426) and corresponding BTM (nCAE=78 and nCLA=123) samples from dairy goat herds enrolled in the Norwegian disease control and eradication programme 'Healthier Goats'. The results showed that the sensitivity and specificity of the CAE ELISA BTM test with respect to detecting ≥2 per cent within-herd prevalence were 72.7 per cent and 86.6 per cent, respectively. For the CLA ELISA BTM the sensitivity and specificity were 41.4 per cent and 81.7 per cent, respectively, for the same goal of detection. The results suggest that BTM testing can be applied as a cost-effective first step for early detection of CAE and CLA infection.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Enfermedades de las Cabras/diagnóstico , Infecciones por Lentivirus/veterinaria , Linfadenitis/veterinaria , Leche/microbiología , Animales , Virus de la Artritis-Encefalitis Caprina/aislamiento & purificación , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/epidemiología , Corynebacterium pseudotuberculosis/aislamiento & purificación , Análisis Costo-Beneficio , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Enfermedades de las Cabras/sangre , Enfermedades de las Cabras/epidemiología , Cabras , Infecciones por Lentivirus/sangre , Infecciones por Lentivirus/diagnóstico , Infecciones por Lentivirus/epidemiología , Linfadenitis/sangre , Linfadenitis/diagnóstico , Linfadenitis/epidemiología , Leche/virología , Noruega/epidemiología , Vigilancia de la Población/métodos , Sensibilidad y Especificidad , Pruebas Serológicas/veterinaria

RESUMEN

BACKGROUND: Sheep caseous lymphadenitis (CLA), caused by Corynebacterium pseudotuberculosis (Cp), is associated with direct economic losses and presents significant zoonotic potential. Despite the importance of the disease, a satisfactory vaccine model has not been developed. Thus, this study aimed to investigate the association between haptoglobin (Hp) and IgM levels and the clinical progression of CLA in primarily infected sheep and in sheep immunized with Cp- secreted antigens adjuvanted with Quillaja saponaria saponins. These animals were kept with CLA-positive sheep to simulate natural exposure that occurs in field conditions. During the experiment, the Hp and IgM levels were monitored for 21 days, and the development of internal CLA lesions was investigated through necropsies on day182 post-immunization. RESULTS: Primarily infected sheep in Group 2 (inoculated with 2x105 Cp virulent strain) had higher Hp values between the first and ninth days post inoculation (PI) than sheep in Group 1 (control; P < 0.05). Immunized animals in Group 3 had significantly higher Hp values between the third and seventh days PI, compared with the control group (P < 0.01). Binary logistic regression (BLR) analysis of primarily infected sheep indicated an association between Hp concentration and CLA clinical progression: animals with high Hp values had 99.9% less risk of having CLA abscesses than animals with low Hp levels (Odds ratio = 0.001, P < 0.05). Both experimental groups had significantly higher IgM titers than the control group around the ninth and eleventh days PI (P < 0.05). The BLR analysis for immunized sheep indicated an association between IgM levels and clinical progression: sheep with high IgM titers had 100.0% less risk of having CLA abscesses than animals with low IgM levels (Odds ratio = 0.000, P < 0.05). CONCLUSIONS: Resistance to C. pseudotuberculosis infection is supported by the early acute phase response, in which up-regulation of Hp and IgM were predictive of a lower risk of CLA lesion development. Because the immunogen used in this study induced a high production of both Hp and IgM, Q. saponaria saponin should be considered a promising candidate in vaccine formulations against sheep CLA.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis , Haptoglobinas/análisis , Inmunoglobulina M/sangre , Linfadenitis/veterinaria , Enfermedades de las Ovejas/microbiología , Animales , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/microbiología , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Linfadenitis/sangre , Linfadenitis/microbiología , Ovinos , Enfermedades de las Ovejas/sangre

RESUMEN

OBJECTIVE: To estimate likelihood ratios (LRs) of correctly identifying internal Corynebacterium pseudotuberculosis infection in horses by measurement of antibody titers via serum synergistic hemolysis inhibition (SHI) testing. DESIGN: Retrospective case-control study. ANIMALS: 170 horses (171 records; 92 cases of C pseudotuberculosis infection and 79 controls). PROCEDURES: Medical records were reviewed, and horses were grouped on the basis of evidence of internal or external C pseudotuberculosis infection. The LRs and 95% confidence intervals for identification of internal C pseudotuberculosis infection by use of SHI test results were estimated. RESULTS: LRs for C pseudotuberculosis infection increased as antibody titers increased when all horses were included in analyses; LRs for detecting internal infection were significantly > 1 (null value) for reciprocal antibody titers ≥ 1,280 overall and > 160 when horses with external abscesses were excluded. Likelihood ratios for detecting internal infection did not differ from 1 (indicating no change in pretest-to-posttest odds of internal infection) when only horses with external C pseudotuberculosis infection (horses with external and internal abscesses vs those with external abscesses only) were included. The LR for detecting internal infection was 2.98 (95% confidence interval, 2.19 to 4.05) for horses with titers ≥ 512. CONCLUSIONS AND CLINICAL RELEVANCE: In the study population, higher titers were typically more indicative of active external or internal C pseudotuberculosis infection than of internal disease specifically. The SHI test was not a useful predictor of internal C pseudotuberculosis infection in horses with external abscesses but was useful in the absence of external disease.

Asunto(s)

Anticuerpos Antibacterianos/sangre , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis , Enfermedades de los Caballos/sangre , Animales , Estudios de Casos y Controles , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/inmunología , Femenino , Enfermedades de los Caballos/inmunología , Enfermedades de los Caballos/microbiología , Caballos , Masculino , Estudios Retrospectivos , Sensibilidad y Especificidad

RESUMEN

An unknown lipophilic coryneform bacterium isolated from the blood cultures of a patient with bacteremia was characterized by phenotypic and molecular genetic methods. Chemical analysis revealed the presence of short chain mycolic acids consistent with the genus Corynebacterium. The DNA G+C content was 60.8 mol%. Comparative 16S rRNA gene sequence analysis demonstrated that the isolate represents a new subline within the genus Corynebacterium. The closely phylogenetic relative of the unknown bacterium was found to be C. tuscaniense (97.8% sequence similarity). Partial rpoB gene sequence revealed that strain IMMIB L-2475(T) exhibited 13.5% sequence divergence with C. tuscaniense. The unknown bacterium was distinguished from C. tuscaniense by, DNA-DNA hybridization, cellular fatty acid profiles, MALDI-TOF analyses of cell extracts and biochemical tests. Based on the phylogenetic and phenotypic criteria, it is proposed that this bacterium be classified as new species, Corynebacterium aquatimens sp. nov., and is represented by strain IMMIB L-2475(T) (=DSM 45632(T)=CCUG 61574(T)).

Asunto(s)

Bacteriemia/microbiología , Infecciones por Corynebacterium/microbiología , Corynebacterium/aislamiento & purificación , Adulto , Bacteriemia/sangre , Proteínas Bacterianas/genética , Composición de Base , Corynebacterium/química , Corynebacterium/clasificación , Corynebacterium/genética , Infecciones por Corynebacterium/sangre , ADN Bacteriano/genética , Humanos , Masculino , Datos de Secuencia Molecular , Ácidos Micólicos/química , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Ribotipificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción

RESUMEN

In the present study, comprehensive data on the seroprevalence of Corynebacterium (C.) pseudotuberculosis infections in goats are presented for Baden-Wuerttemberg, a Federal State of Germany, for the first time. As a prerequisite, ELISAs based on a recombinant phospholipase D (rPLD) and whole cell antigens (WCA) were designed and validated yielding sensitivity values of 81% and 97% and specificity values of 98% and 99%, respectively. Immunisation trials in goats demonstrated a significant production of antibodies to rPLD but an evidently lower antibody production to WCA as determined in the corresponding ELISA. Moreover, immunisation with rPLD resulted in the formation of antibodies, which were also detected in the WCA ELISA. In contrast, this phenomenon was not observed with the rPLD ELISA after immunisation with WCA. Implementation of the rPLD and WCA ELISAs in a broad-based seroprevalence study in Baden-Wuerttemberg revealed positive reactions in both ELISAs in 13.2% of the 1771 goat sera tested. In 53.7% of 121 herds of which five or more animals were tested per herd there was at least one animal that showed a positive reaction in both tests.

Asunto(s)

Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Infecciones por Corynebacterium/veterinaria , Ensayo de Inmunoadsorción Enzimática , Enfermedades de las Cabras/diagnóstico , Animales , Vacunas Bacterianas/inmunología , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/epidemiología , Corynebacterium pseudotuberculosis , Alemania/epidemiología , Enfermedades de las Cabras/sangre , Enfermedades de las Cabras/epidemiología , Cabras , Fosfolipasa D/inmunología , Proteínas Recombinantes/inmunología , Reproducibilidad de los Resultados , Estudios Seroepidemiológicos , Vacunas Sintéticas/inmunología

Asunto(s)

Antibacterianos/sangre , Antibacterianos/uso terapéutico , Cateterismo Venoso Central/efectos adversos , Catéteres de Permanencia/microbiología , Daptomicina/sangre , Daptomicina/uso terapéutico , Sepsis/tratamiento farmacológico , Corynebacterium/aislamiento & purificación , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/tratamiento farmacológico , Femenino , Humanos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Persona de Mediana Edad , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/tratamiento farmacológico , Insuficiencia del Tratamiento

RESUMEN

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis, a disease that affects goats and sheep, and can cause severe economic losses. In this study, four different antigenic extracts were obtained from the attenuated strain T1, which was isolated in the state of Bahia (Brazil). Forty-four Canindé breed goats were divided in five groups, each receiving a different antigen solution and saline buffer as a control. The humoral response was monitored through the identification of specific IgG by indirect ELISA and Western Blotting, and the production of IFN-gamma was followed in order to observe the activation of cellular response. After twelve weeks of antigen inoculation, the animals were challenged with 2 x 10(5)CFU of a wild strain, also isolated in Bahia, and necropsy was performed on all animals twelve weeks afterwards. It was observed that the attenuated bacteria gave a protection of 33.3%, in addition to the weak humoral response elicited. Animals inoculated with secreted antigen associated with Freund's incomplete adjuvant and oligodeoxynucleotide containing unmethylated CpG dinucleotides (CpG ODN) showed a strong humoral response, but this inoculation could not prevent the spread of challenge bacteria in the majority of animals. These results demonstrate the immunogenic potential of the attenuated T1 strain in the development of a vaccine against caseous lymphadenitis in goats.

Asunto(s)

Antígenos Bacterianos/inmunología , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis , Enfermedades de las Cabras/prevención & control , Linfadenitis/veterinaria , Animales , Vacunas Bacterianas/inmunología , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/inmunología , Enfermedades de las Cabras/sangre , Enfermedades de las Cabras/inmunología , Cabras , Immunoblotting , Inmunoglobulina G/sangre , Interferón gamma/sangre , Linfadenitis/prevención & control

RESUMEN

Caseous lymphadenitis (CLA), a chronic bacterial disease of sheep and goats caused by Corynebacterium pseudotuberculosis, could be controlled by eradication of infected carriers. This study aimed at validation of a whole blood interferon-gamma (IFN-gamma) enzyme immunoassay (EIA) (Bovigam, Pfizer) in naturally infected sheep for use in eradication of infection from a flock. This assay used formalin-inactivated whole bacterial cells as antigen. The sensitivity of the whole cell assay was improved by increasing both the volume of blood and the number of bacterial cells. The assay was validated in experimentally infected sheep and in a flock of known-negative sheep, as well as in a naturally infected flock, a proportion of which was vaccinated with a commercial CLA vaccine. An optical density (540nm) (OD) cut-off of 0.09 was effective in classifying animals as test positive or negative in the naturally infected flock, although there was variation in OD between visits, notably with weakly reacting animals. The test had a sensitivity of 91% and a specificity of 98%. Postmortem data supported the results in test-negative animals. Visit-to-visit variation in IFN-gamma EIA OD in the naturally infected flock as well as CLA disease status was used to develop an algorithm for the eradication of CLA from a known infected flock. The whole blood IFN-gamma assay shows promise for eradication of caseous lymphadenitis from sheep flocks.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/inmunología , Técnicas para Inmunoenzimas/veterinaria , Interferón gamma/inmunología , Linfadenitis/veterinaria , Enfermedades de las Ovejas/diagnóstico , Animales , Antígenos Bacterianos/sangre , Antígenos Bacterianos/inmunología , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/diagnóstico , Femenino , Técnicas para Inmunoenzimas/métodos , Técnicas para Inmunoenzimas/normas , Interferón gamma/sangre , Linfadenitis/sangre , Linfadenitis/diagnóstico , Masculino , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/sangre , Vacunación/métodos , Vacunación/veterinaria

RESUMEN

Several enzyme-linked immunosorbent assays (ELISAs) have been developed for the detection of antibodies to Corynebacterium pseudotuberculosis, the causative agent of caseous lymphadenitis (CLA). However, none are commercially available in the UK. It was therefore necessary to develop a new, economic ELISA for use in a research project studying the epidemiology of CLA in UK sheep. The ELISA with its diagnostic qualities is presented. The ELISA was developed using sonicated C. pseudotuberculosis and optimised to detect total antibody or IgG class antibody in serum. Receiver operating characteristic (ROC) curves were obtained and the area under the ROC curve was used to compare the sensitivity and specificity of the two ELISAs. Both versions of the ELISA were evaluated on a panel of 150 positive reference sera and 103 negative reference sera. Using the test at 100% specificity, the sensitivity of detection of total antibody was 71% (95% confidence interval 63-78%), and the sensitivity of detection of IgG antibody to C. pseudotuberculosis was 83% (76-89%), which compares favourably with other reported ELISA tests for CLA in sheep. The sensitivity of the IgG antibody assay may be higher because of the greater affinity of IgG class antibodies compared with the IgM antibodies also detected by the total antibody ELISA. The results of ROC analysis indicated that the IgG isotype ELISA was more accurate than the total antibody ELISA. The efficiency of the test was greatest when serum samples were run in a dilution series than when any single serum dilution was used. The ELISA is considered to be suitable for application in field studies of CLA in UK sheep.

Asunto(s)

Anticuerpos Antibacterianos/sangre , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de las Ovejas/sangre , Enfermedades de las Ovejas/diagnóstico , Ovinos/sangre , Animales , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina G/sangre , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ovinos/inmunología , Ovinos/microbiología , Enfermedades de las Ovejas/inmunología , Enfermedades de las Ovejas/microbiología , Reino Unido

RESUMEN

Since haematological variables can be used to assess the health state in cultured fish, a haematological characterization of clinically healthy Oreochromis aureus was done to establish the reference indices of this species. Fish were subjected to different stressed conditions (bacterial infection, nitrite intoxication, malachite green overdose) to study the changes in the haematological indices and its relation with the health condition. This species showed microcytic anaemia under experimental bacterial infection by Corynebacterium sp.; anaemia, neutrophilia and erythrocytes deformation following nitrite intoxication and medication overdose with malachite green.

Asunto(s)

Cíclidos/sangre , Infecciones por Corynebacterium/veterinaria , Enfermedades de los Peces/sangre , Nitritos/toxicidad , Colorantes de Rosanilina/toxicidad , Anemia/inducido químicamente , Animales , Infecciones por Corynebacterium/sangre , Eritrocitos Anormales/efectos de los fármacos , Pruebas Hematológicas , Neutrófilos/metabolismo

RESUMEN

The inoculation of 2000 colony-forming units of Corynebacterium pseudotuberculosis into one teat canal of each of three cows resulted in severe, chronic, pyogranulomatous mastitis. Within three days the cows had a reduced haematocrit, haemoglobin concentration and red cell count. The anaemia was initially normocytic, normochromic and non-regenerative, and was associated with a brief peak of neutrophilia; a regenerative response became evident two to three weeks later. Clinical signs of mastitis appeared seven to 14 days after the inoculation, with a peak of high fever, more severe anaemia, a second peak of neutrophilia and the complete cessation of milk production from all quarters; extensive and severe pyogranulomatous mastitis developed in the inoculated quarters. No other lesions were detected postmortem, and C pseudotuberculosis was cultured from the affected quarters but not from the supramammary lymph nodes and viscera.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/patogenicidad , Mastitis Bovina/microbiología , Anemia/microbiología , Anemia/patología , Anemia/veterinaria , Animales , Bovinos , Recuento de Células/veterinaria , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/patología , Femenino , Lactancia , Glándulas Mamarias Animales/microbiología , Glándulas Mamarias Animales/patología , Mastitis Bovina/sangre , Mastitis Bovina/patología , Leche/citología , Leche/microbiología , Neutrófilos/patología

RESUMEN

OBJECTIVE: To determine whether the spread of Corynebacterium pseudotuberculosis infection to sheep in dips could be controlled by increasing the time between shearing and dipping. DESIGN: A controlled treatment trial where only the time between shearing and dipping was varied. ANIMALS AND PROCEDURE: One hundred and ninety-five sheep were found to be negative for C. pseudotuberculosis exposure by assay of CLA toxin antibody, were divided into four treatment groups. Each was shorn at either 0, 2, 4 or 8 weeks before dipping in a solution containing C. pseudotuberculosis. Blood samples were taken 6 weeks after dipping and sheep were slaughtered 12 weeks after dipping. A fifth smaller group of 14 sheep shorn 26 weeks before dipping, was also exposed to C. pseudotuberculosis and was slaughtered with the other sheep. RESULTS: The occurrence of caseous lymphadenitis abscesses did not differ between groups or with sheep shorn 26 weeks before dipping. The proportion of sheep that seroconverted to the C. pseudotuberculosis toxin and cell wall ELISA was larger in sheep dipped immediately after shearing than in sheep in the other groups. CONCLUSIONS: Delaying dipping until 8 weeks after shearing did not decrease the C. pseudotuberculosis infection rate due to dipping. Sheep dipped immediately after shearing developed higher concentrations of antibody to C. pseudotuberculosis than sheep when dipping occurred between 2 and 8 weeks and later after shearing.

Asunto(s)

Crianza de Animales Domésticos/métodos , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis , Transmisión de Enfermedad Infecciosa/veterinaria , Enfermedades de las Ovejas/transmisión , Animales , Anticuerpos Antibacterianos/sangre , Toxinas Bacterianas , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/transmisión , Corynebacterium pseudotuberculosis/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Linfadenitis/sangre , Linfadenitis/microbiología , Linfadenitis/veterinaria , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/sangre , Enfermedades de las Ovejas/microbiología , Factores de Tiempo

RESUMEN

The optimal method of control of caseous lymphadenitis of sheep caused by Corynebacterium pseudotuberculosis is eradication of infection by identification and removal of infected carrier animals. Current serological approaches to identification of infected sheep are generally hampered by low sensitivity and specificity of available tests. The objective of this study was to develop a whole blood assay for detection of C. pseudotuberculosis-infected sheep, based on detection of IFN-gamma response to whole cell C. pseudotuberculosis antigens, and to determine the reliability of the assay. A commercially available bovine interferon-gamma assay enzyme-linked immunosorbent assay was used and the test optimised using experimentally infected sheep. The assay was also tested on known CLA-negative sheep. Setting a IFN-gamma optical density cut-off at 0.100 as positive under the conditions used, the test detected C. pseudotuberculosis experimentally infected sheep over a 450-day period with a reliability of 95.7%. It identified known non-infected sheep with a reliability of 95.5%. Repeated vaccination of three uninfected sheep with a commercially available bacterin-toxoid vaccine did not interfere with the assay. The IFN-gamma response of sheep whole blood to C. pseudotuberculosis antigens offers promise for use in a test-and-removal approach to eradication of CLA in sheep.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/inmunología , Interferón gamma/inmunología , Linfadenitis/veterinaria , Enfermedades de las Ovejas/diagnóstico , Animales , Antígenos Bacterianos/sangre , Antígenos Bacterianos/inmunología , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/inmunología , Corynebacterium pseudotuberculosis/crecimiento & desarrollo , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Interferón gamma/sangre , Linfadenitis/sangre , Linfadenitis/inmunología , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/inmunología , Vacunación/veterinaria

RESUMEN

Twenty goats, in two groups of 10, were injected intradermally with Corynebacterium pseudotuberculosis. The doses of infection were 1 x 10(5) and 5 x 10(4) colony-forming units (cfu) for groups 1 and 2, respectively. Thereafter, a goat from each group was killed every 2-3 days and examined for gross and microscopic caseous lesions in the draining lymph nodes. Bands or zones of macrophages and polymorphonuclear granulocytes were observed microscopically on the second day of infection in both groups. Gross caseous lesions were observed from days 8 and 9 of infection, respectively. Positive bacterial agglutination test and haemolysis inhibition test titres were detected after 15-17 days and 20-25 days of infection, respectively. These results indicated that caseous lymphadenitis is a subacute disease with an incubation period of 8-9 days, but that it is not detectable serologically until after 15 days of infection.

Asunto(s)

Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/crecimiento & desarrollo , Enfermedades de las Cabras/microbiología , Linfadenitis/veterinaria , Absceso/microbiología , Absceso/patología , Absceso/veterinaria , Pruebas de Aglutinación , Animales , Anticuerpos Antibacterianos/sangre , Infecciones por Corynebacterium/sangre , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/patología , Enfermedades de las Cabras/sangre , Enfermedades de las Cabras/patología , Cabras , Ganglios Linfáticos/anatomía & histología , Ganglios Linfáticos/microbiología , Ganglios Linfáticos/patología , Linfadenitis/sangre , Linfadenitis/microbiología , Linfadenitis/patología , Masculino , Tamaño de los Órganos , Distribución Aleatoria