Utility assessment of an Enzyme-linked immunosorbent assay for detection of subclinical cases of caseous lymphadenitis in small ruminant flocks.

The actual prevalence of CLA (caseous lymphadenitis) in small ruminant flocks is underestimated in many countries, and because it is not a notifiable disease, it will continue to spread without data and information about its real economic impact. The difficulty in the accurate identification of the causative agent in internal subclinical cases allows the disease to spread within and between flocks. This research intends to assess the utility of an ELISA (enzyme-linked immunosorbent assay) test in the detection of internal subclinical cases of CLA in farms and to simultaneously add data on the seroprevalence of the disease in Portugal. Sera from 756 small ruminants, 70% sheep (528/756) and 30% goats (228/756) were screened for antibodies against Corynebacterium pseudotuberculosis using the ELISA technique based on a recombinant phospholipase D (ELITEST CLA # CK105A® ). The animals showing internal lesions (n êžŠ 58) were sampled for the identification of the aetiological agent. In this investigation, the prevalence of CLA was 34% (258/756), with the ELISA test showing a low specificity (78%) and high sensitivity (100%). The proof was able to detect 57% (13/23) of subclinical cases of CLA confirmed by postmortem examination and conventional PCR (polymerase chain reaction). The results also reveal that goats have a higher propensity for the disease, and dairy farms and non-extensive production units appear to be more susceptible to CLA. This research clarifies an actual problem and pointed out the importance of CLA in small ruminant herds in Portugal. Finally seems to demonstrate that the ELISA test is a good diagnostic tool for use in CLA eradication programmes.

Seroepidemiological study of Caseous lymphadenitis in sheep from the Northeast region of Brazil using an indirect ELISA.

The objective of this study was to determine the frequency of seropositivity Corynebacterium pseudotuberculosis in sheep in five states of northeastern Brazil, using an indirect enzyme-linked immunosorbent assay (i-ELISA). Young and adult sheep of both sexes were used. Blood samples were collected from 2638 sheep from 223 herds across all states. For the i-ELISA, antigens produced from the strain of C. pseudotuberculosis BRM 029971, a bacterial isolate from the Northeast region of Brazil, were used. Sensitivity and specificity indexes were calculated for the validation of the test, using as reference 49 and 134 serum samples from sheep known to be positive and negative, respectively. The i-ELISA presented four false-negative and four false-positive results, showing a specificity of 97.01%, a sensitivity of 91.84%, and an accuracy of 95.63%. These results were calculated based on an optical density (OD) cutoff point = 0.138. Of the 2638 sheep tested, 996 (37.76%, 95% CI = 35.93-39.62%) were seropositive, and of the 223 evaluated herds, 210 (94.17%, 95% CI = 90.28-96.56%) seropositive. The i-ELISA showed adequate sensitivity and specificity, proving to be a useful tool in the diagnosis of caseous lymphadenitis (CLA) in sheep. Infection by C. pseudotuberculosis, determined by serology, is disseminated in the sheep herds in the states of Northeast Brazil. Thus, there is a need to implement effective control measures that prevent the spread of infectious agents.

Clinico-pathological responses and PCR detection of Corynebacterium pseudotuberculosis and its immunogenic mycolic acid extract in the vital organs of goats.

Caseous lymphadenitis is an infectious disease of almost all animals, particularly small ruminants that are caused by Corynebacterium pseudotuberculosis. The organism causes the formation of suppurative abscesses in superficial and visceral lymph nodes and in visceral organs. This current study was designed to elucidate the clinicopathological responses and PCR detection of the aetiological agent in the vital organs of goats challenged with C. pseudotuberculosis and its immunogenic mycolic acid extract. A total of twelve clinically healthy crossbred Boer female goats were divided into three groups: A, B, and C (four goats per group). Group A was inoculated intradermally with 2 ml of sterile phosphate buffered saline (PBS) pH 7 as a control group. Group B was inoculated intradermally with 2 ml of mycolic acid extract (1 g/ml), while group C was inoculated intradermally with 2 ml of 109 colony-forming unit (cfu) of live C. pseudotuberculosis. The experimental animals were observed for clinical responses for 90 days post-inoculation and the clinical signs were scored according to the severity. The clinical signs observed in this study were temperature, heart rate, respiratory rate, rumen motility, enlargement of lymph nodes, and body condition score. The experimental animals were euthanised and tissue samples from different anatomical regions of the vital organs were collected in 10% buffered formalin, processed, sectioned, and stained with H&E. Results of both C. pseudotuberculosis and mycolic acid treated groups indicated a significant difference (p < 0.05) in body temperature. Group C showed a significant increase in temperature (p < 0.05) at week 1 (39.59 ±â€¯0.29 °C), week 2 (39.67 ±â€¯0.27 °C) and week 3 (40.22 ±â€¯0.15 °C). Whereas group B showed a significant increase in temperature (p < 0.05) only at week 1 (39.36 ±â€¯0.14 °C). Heart rate in group C showed a significant increase between week 1 (93.35 ±â€¯0.42 bpm) and week 11 (86.52 ±â€¯1.32 bpm), and the mean heart rate of group B showed a significant increase (p < 0.05) between week 1 (89.90 ±â€¯0.60 bpm) and week 9 (86.90 ±â€¯0.99 bpm). Group C showed a significant increase of respiratory rate (p < 0.05) at week 1 (36.85 ±â€¯0.14 bpm), week 2 (36.90 ±â€¯0.62), week 3 (30.80 ±â€¯1.97 bpm), and week 4 (34.85 ±â€¯1.19 bpm). The mean of the respiratory rate of group B only increased at week 1 (32.98 ±â€¯1.30 bpm) and week 2 (31.87 ±â€¯0.48 bpm). Both groups C & B showed significant decreases in rumen motility and body condition score as compared to the control. The histopathological changes were significant in group C, this was shown by mild to severe haemorrhage, congestion, degeneration and necrosis, oedema, infiltration with inflammatory cells mainly lymphocytes and macrophages, while group B was less affected and showed mild to moderate haemorrhage, congestion, degeneration and necrosis, infiltration of inflammatory cells and oedema as compared to the control group. This study concluded that C. pseudotuberculosis caused typical CLA disease with a short incubation period in the experiment. While the mycolic acid extracted from C. pseudotuberculosis caused mild clinical signs, no abscess formation, and negative PCR result. Moreover, evidence of mild to moderate histopathological changes in vital organs was also observed.

[Corynebacterium pseudotuberculosis biovar ovis: Evaluation of antibiotics susceptibility in vitro]. / Corynebacterium pseudotuberculosis biovar ovis: evaluación de la sensibilidad antibiótica in vitro.

The aims of this work were to study the antibiotic susceptibility in Corynebacterium pseudotuberculosis isolated from small ruminants and to determine the presence of integrons that contain resistance genes. Fifteen isolates of different sources were analysed using the diffusion and the dilution methods. When the diffusion method was performed, amoxicillin-clavulanic, ampicillin, cefotaxime, cefoxitin, ciprofloxacin, chloramphenicol, erythromycin, streptomycin, gentamicin, imipenem, kanamycin, norfloxacin, penicillin, rifampicin, tetracycline, trimethoprim-sulfamethoxazole and vancomycin were effective against the 100% of isolates, while amikacin showed variable results. The isolates that were able to grow with amikacin, were studied in relation to the presence of integron class1. The result was negative, suggesting the absence of integron. Using dilution method, the antibiotics belonging to the cephalosporin, glycopeptide, macrolide, quinolone, and tetracycline groups were the most active ones for the C.pseudotuberculosis biovar ovis isolates. Less activity of ß-lactam and aminoglycosides were observed. There was no observation of variability in the antibiotic patterns in the strains coming from different sources.

Seroepidemiological characterization and risk factors associated with seroconversion to Corynebacterium pseudotuberculosis in goats from Northeastern Brazil.

Goat breeding in the Northeast region of Brazil plays an important socioeconomic role. However, there are significant losses caused by sanitary deficits and infectious diseases, particularly caseous lymphadenitis (CL). Although CL is considered endemic in Northeastern Brazil, a comprehensive and up-to-date study of this disease in goat herds in this region is necessary. The objective of this study was to determine the farm-level and animal-level seroprevalences for the disease and to identify the possible risk factors that characterize CL in the caprine species of five Northeastern's states (Ceará, Piauí, Rio Grande do Norte, Paraíba, and Sergipe). A total of 2744 goat serum samples from 230 farms were collected between 2010 and 2012. The diagnosis of Corynebacterium pseudotuberculosis infection was performed using the indirect ELISA technique. Farm-level and animal-level seroprevalences were 87.8% and 30.3%, respectively, suggesting that C. pseudotuberculosis is widespread in goat herds of the Northeast region. The risk factors were as follows: absence of forage silage (odds ratio = 5.39), not separating animals by sex (odds ratio = 4.16) or by age (odds ratio = 6.30), not replacing old goat breeders (odds ratio = 7.80), and non-treatment of CL lumps prior to spontaneous rupture (odds ratio = 10.34). This study supports the idea that caseous lymphadenitis is widely disseminated in goats from Northeastern Brazil and based on the risk factor analysis attention should be given to the need to establish adequate control measures, such as incision and early drainage of superficial abscesses, quarantine and elimination of affected animals, periodic inspection of the herd, non-introduction of infected animals, and early disposal of animals with recurrent CL.

Sensibilidade in vitro a antimicrobianos de Corynebacterium pseudotuberculosis isolados de pequenos ruminantes da região Centro- Norte do Estado da Bahia / In vitro antimicrobial susceptibility of Corynebacterium pseudotuberculosis isolated from small ruminants from the North-Central region of the State of Bahia

Introdução: corynebacterium pseudotuberculosis é uma bactéria com importância em medicina veterinária por ser o agente etiológico da Linfadenite Caseosa (LC) em pequenos ruminantes. A doença leva a perdas econômicas devido a condenação de carcaças, diminuição de produtividade e redução do valor comercial do couro dos animais acometidos. O tratamento da doença é pouco eficaz, pois os agentes antimicrobianos não conseguem atravessar a barreira dos granulomas, mas tem sido proposta a inoculação intracapsular de antibióticos como tratamento e como medida de prevenção de contaminação ambiental. Objetivo: devido a esse fato, o presente estudo teve como objetivo avaliar a sensibilidade in vitro de isolados clínicos de Corynebacterium pseudotuberculosis isolados de animais da região Centro-Norte do estado da Bahia. Metodologia: foram retirados material de granulomas de 11 animais de uma fazenda na região acima mencionada, e as bactérias foram isoladas a partir desse material. Esses isolados então foram submetidos a metodologia de difusão em disco de ágar utilizando-se discos impregnados com doze antibióticos diferentes. Resultados: 90,9% (10/11) dos isolados foram resistentes a oxacilina. Com relação à sensibilidade, 100% dos isolados foram sensíveis a ampicilina, amicacina, amoxicilina, cefalotina, ceftriaxona, ciprofloxacina, enrofloxacina, neomicina e penicilina, enquanto 90,9% destes apresentaram sensibilidade a bactericina e doxiciclina. Conclusão: pode-se concluir que os isolados de C. pseudotuberculosis da região estudada apresentam sensibilidade a diversos antibióticos, o que pode facilitar na escolha de um antimicrobiano com menor toxicidade para fins de tratamento com inoculação intracapsular do medicamento.

Background: corynebacterium pseudotuberculosisis important bacteria in veterinary medicine because it is the Etiologic Agent of Caseous Lymphadenitis (CL) in small ruminants. The disease leads to economic losses due to condemnation of carcasses, productivity decrease and leather commercial value reduction of affected animals affected. The treatment of the disease is not very effective, because antimicrobial agents cannot cross the barrier of granulomas, but it has been proposed the intracapsular inoculation of antibiotics as treatment and as a measure of prevention of environmental contamination. Objective: due to this fact, the present study aimed to evaluate the in vitro susceptibility of clinical isolates of Corynebacterium pseudotuberculosis isolated from animals in the North Central region of the State of Bahia. Methodology: granuloma material were removed from 11 animals from a farm in the above mentioned area, and the bacteria were isolated from this material. These isolated bacteria were then subjected to disk diffusion method of agar using disks impregnated with twelve different antibiotics. Results: 90,9% (10/11) the isolated bacteria were resistant to oxacillin.With respect to sensitivity, 100% of the isolates bacteria were susceptible to amikacin, ampicillin, amoxicillin, cephalotin, ceftriaxone, ciprofloxacin, enrofloxacin, neomycin and penicillin, while 90.9% of these showed sensitivity to bacitracin and doxycycline. Conclusion: it can be concluded that the isolated bacteria of C. pseudotuberculosis from the region studied present sensitivity to different antibiotics, which can facilitate the choice of a less toxic antimicrobial for treating with intracapsular inoculation of the medicine.

Tumor cervical de etiología inusual / Cervical tumor unusual etiology

No disponible

Resistance of Corynebacterium pseudotuberculosis in the Brazilian semiarid environment / Resistência de Corynebacterium pesudotuberculosis no ambiente do semiárido brasileiro

The semiarid northeast of Brazil contains a unique biome known as caatinga, with a maximum temperature of 40 ºC and a relativity humidity of 56%. The caatinga is characterized by a variety of plants, including Cereus jamacaru Dc (mandacaru), Poincianella microphylla Mart. ex G. Don (catingueira), Pilosocereus gounellei FAC Weber (xique-xique) and Mimosa tenuiflora (Willd.) Poir (jurema preta). Sheep and goat industries are economically strong in that region, despite the fact that caseous lymphadenitis is highly prevalent. The aim of the present study was to assess the survival and biofilm production of Corynebacterium pseudotuberculosis isolates in the environment and under controlled temperatures (28°C, 37°C and 42°C) under different surfaces (plants, soil, wood, wire and thorns). In addition, we investigated the effects of applying the disinfectants chlorhexidine, hypochlorite and quaternary ammonia in soil, tiles, wood and vegetation cover. Four strains of C. pseudotuberculosis were selected (two from goats and two from sheep) for inoculation according to their in vitro biofilm production. Adherence to microplates was used to assess the biofilm-forming ability of the bacteria. Lower survival rates were observed when isolates of C. pseudotuberculosis were subjected to a temperature of 42°C. In terms of caatinga biome plants, contamination of jurema-preta plants resulted in the lowest survival rates. The disinfectant quaternary ammonia promoted a lower inoculum survival in all surfaces. The disinfectants and the higher temperature contributed to the reduction of biofilm production in isolates of C. pseudotuberculosis. knowledge of these patterns is important for the establishment of disease control measures, given the questionable efficacy of the treatment and the immuno-prophylaxis of caseous lymphadenitis.(AU)

O semiárido nordestino do Brasil possui um bioma exclusivo, a caatinga, que apresenta temperatura máxima de 40oC e uma umidade relativa do ar de 56%. A caatinga é caracterizada por uma diversidade de plantas, entre elas Cereus jamacaru DC. (mandacaru), Poincianella microphylla Mart ex G. Don (catingueira), Pilosocereus gounellei F.A.C. Weber (xique-xique) e Mimosa tenuiflora (Willd.) Poir (jurema preta). A produção de ovinos e caprinos está em franca expansão, porém a linfadenite caseosa é uma enfermidade de alta prevalência na região. Objetiva-se com o presente estudo, verificar a sobrevivência e produção de biofilme em isolados de Corynebacterium pseudotuberculosis em temperaturas de 28oC, 37oC e 42oC, quando inoculado em superfícies de solo, madeira, arame e espinho e em plantas nas condições ambientais da caatinga. Além disto, foi verificado o efeito da aplicação dos desinfetantes clorexidine, hipoclorito e amônia quaternária sobre o solo, piso (lajota), madeira e vegetação de cobertura do solo. Foram selecionadas quatro amostras de C. pseudotuberculosis (dois caprinos e dois ovinos) para inoculação de acordo com a sua produção in vitro de biofilme. A adesão a microplacas foi utilizado para avaliar a capacidade de formação de biofilme das bactérias. As menores taxas de sobrevivência foram observadas quando isolados de C. pseudotuberculosis foram submetidos a uma temperatura de 42°C. Com relação as plantas do bioma caatinga, a contaminação na planta jurema-preta apresentou menores índices de sobrevivência. O desinfetante amônia quartenária promoveu uma menor sobrevivência do inóculo em todas as superfícies. Os desinfetantes e temperatura contribuíram para a redução na produção de biofilme nos isolados de Corynebacterium pseudotuberculosis. O conhecimento destes padrões é importante para o estabelecimento de medidas de controle da enfermidade, dada a eficiência questionável do tratamento e imunoprofilaxia da linfadenite caseosa.(AU)

Isolation and molecular characterization of Corynebacterium pseudotuberculosis from sheep and goats in Mexico.

The pathogenic bacteria of Corynebacterium pseudotuberculosis caused a chronic contagious infectious disease of the caseous lymphadenitis or pseudotuberculosis. Globally, isolates obtained from different injuries that affect sheep and goats, have been identified by fully or partially gene sequencing. However, in Mexico there is no complete study to identify by molecular and phylogenetic techniques the circulating isolates as well as its virulence factors. Therefore, in the present study we reported the identification of 57 isolates of C. pseudotuberculosis by bacteriological tests and the amplification of 16S rRNA, rpoB and pld genes, as well as, genes involved in virulence and pathogenicity: Fag A, Fag B, Fag C, Fag D and hsp60. Phylogenetic analysis was performed based on the partial sequence of the rpoB gene. Genes involved in virulence and pathogenicity were identified in the 98.2% of the isolates. Regarding the phylogenetic analysis, were identified the species and subspecies to which they belong of all the tested isolates. The phenotypic and genotypic characterization will allow to establish preventive and prophylactic measures aimed to the creation of effective immunogens against Corynebacterium pseudotuberculosis.

Responses of haptoglobin and serum amyloid A in goats inoculated intradermally with C. pseudotuberculosis and mycolic acid extract immunogen.

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.

CORYNEBACTERIUM PSEUDOTUBERCULOSIS AND COPPER DEFICIENCY IN A MALE ROCKY MOUNTAIN BIGHORN SHEEP ( OVIS CANADENSIS CANADENSIS) IN UTAH, USA.

: In 2015, an emaciated Rocky Mountain bighorn ( Ovis canadensis) ram was submitted to the Utah Veterinary Diagnostic Laboratory for necropsy. There were numerous thick-walled abscesses subcutaneously and internally, and Corynebacterium pseudotuberculosis was isolated in pure culture. In addition, the ram was severely copper deficient, with a liver copper concentration of 1.6 mg/kg.

Heat shock stress: Profile of differential expression in Corynebacterium pseudotuberculosis biovar Equi.

Transcriptome studies on Corynebacterium pseudotuberculosis have recently contributed to the understanding about this microorganism's survival mechanisms in various hostile conditions. The gene expression profile of the C. pseudotuberculosis strain 1002 (Ovis biovar), has revealed genes that are possible candidates responsible for its maintenance in adverse environments, such as those found in the host. In another strain of this bacterium, 258 (Equi biovar), a high temperature condition was simulated, in order to verify which genes are responsible for promoting the persistence of the bacterium in these conditions, since it tolerates temperatures higher than 40°C, despite being a mesophilic bacterium. It was possible to generate a list of genes using RNAseq technology that possibly contribute to the survival of the bacteria in this hostile environment. A total of 562 genes were considered as differentially expressed, then, after the fold-change cutoff, 113 were considered induced and 114 repressed, resulting in a total of 227 genes. Therefore, hypothetical proteins presented a fold change above 6, and genes characteristically in control for this type of stress, such as hspR, grpE, and dnaK, presented a fold change above 3. The clpB gene, a chaperone, drew attention due to presenting a fold change above 3 and located in a pathogenicity island. These genes may contribute towards efficient solutions to the effects caused by ulcerative lymphangitis in equines, thus attenuating the damage it causes to agribusiness.

Quadruplex PCR assay for identification of Corynebacterium pseudotuberculosis differentiating biovar Ovis and Equi.

BACKGROUND: Corynebacterium pseudotuberculosis is classified into two biovars, nitrate-negative biovar Ovis which is the etiologic agent of caseous lymphadenitis in small ruminants and nitrate-positive biovar Equi, which causes abscesses and ulcerative lymphangitis in equines. The aim of this study was to develop a quadruplex PCR assay that would allow simultaneous detection and biovar-typing of C. pseudotuberculosis. METHODS: In the present study, genomes of C. pseudotuberculosis strains were used to identify the genes involved in the nitrate reduction pathway to improve a species identification three-primer multiplex PCR assay. The nitrate reductase gene (narG) was included in the PCR assay along with the 16S, rpoB and pld genes to enhance the diagnosis of the multiplex PCR at biovar level. RESULTS: A novel quadruplex PCR assay for C. pseudotuberculosis species and biovar identification was developed. The results of the quadruplex PCR of 348 strains, 346 previously well-characterized clinical isolates of C. pseudotuberculosis from different hosts (goats, sheep, horse, cattle, buffalo, llamas and humans), the vaccine strain 1002 and the type strain ATCC 19410T, were compared to the results of nitrate reductase identification by biochemical test. The McNemar's Chi-squared test used to compare the two methods used for C. pseudotuberculosis biovar identification showed no significant difference (P = 0.75) [95% CI for odds ratio (0.16-6.14)] between the quadruplex PCR and the nitrate biochemical test. Concordant results were observed for 97.13% (338 / 348) of the tested strains and the kappa value was 0.94 [95% CI (0.90-0.98)]. CONCLUSIONS: The ability of the quadruplex assay to discriminate between C. pseudotuberculosis biovar Ovis and Equi strains enhances its usefulness in the clinical microbiology laboratory.

[Screening of Corynebacterium diphtheriae, Corynebacterium ulcerans and Corynebacterium pseudotuberculosis in throat swab specimens of children with upper respiratory tract infections]. / Üst solunum yolu enfeksiyonu bulgulari ile basvuran çocuklarin bogaz sürüntü örneklerinde Corynebacterium diphtheriae, Corynebacterium ulcerans ve Corynebacterium pseudotuberculosis suslarinin arastirilmasi.

Although a significant decrease has been reported in the incidence of diphteria in many regions of the world following the routine diphtheria immunization programs, the emergence of new cases indicated that toxigenic strains are still circulating in the community. Diphtheria vaccine does not provide protection against asymptomatic carriage and colonization of non-toxigenic Corynebacterium diphtheriae. It is a known fact that invasive infections may arise from non-toxigenic C.diphtheriae strains that the non-toxigenic strains can become toxigenic strains leading to diphteria. It is also known that there is a risk of diphteria outbreaks due to decreased antitoxin level and inadequate adult immunization programs. In our country, there is no routine surveillance of toxigenic and non-toxigenic C.diphtheriae. In the present study we aimed to investigate the presence of C.diphtheriae, Corynebacterium ulcerans and Corynebacterium pseudotuberculosis in children presenting with the symptoms of upper respiratory tract infections that might be confused with those moderate diphteria, in order to highlight the requirement of microbiological surveillance and to create awareness about these microorganisms among public health experts, microbiologists and clinicians. Throat swab specimens were obtained from children who were admitted to the pediatric outpatient clinics, in Dr. Sami Ulus Obstectrics, Children Health and Diseases Educational and Research Hospital, with upper respiratory tract infections between 1 February 2016-22 March 2016. The specimens were inoculated in 5% sheep blood agar plates. The plates that were incubated in appropriate conditions, were evaluated for Group A beta hemolytic streptococcocci. Subsequently, culture plates were sent to the Public Health Institution of Turkey, National Respiratory Pathologens Reference Laboratories for the investigation of the presence of C.diphtheriae, C.ulcerans and C.pseudotuberculosis. The growth in each plate were collected with a sterile swab and inoculated in tryptic soy broth. Following 2 hours of incubation at 37oC, subcultures were inoculated in cystine-tellurite-blood agar (CTBA) and 5% sheep-blood agar plates; after an overnight incubation tellurite-reducing colonies were inoculated in Tinsdale agar plates. The suspected colonies with positive cystinase activity were identified by conventional methods and also with Coryne API (Biomerieux, France) systems. Toxicity tests (ELEK, PCR) were performed to investigate whether the C.diphtheriae strains were producing toxins. A total of 500 patients were involved in the study. Of these 260 (52%) were girls and 240 (48%) were boys with a mean age of 76 (range, 21-213) months. All patients except one were fully vaccinated with boosters. Most common presenting symptoms of the patients were fever (19.8%), sore throat (52.6%), cough (49.2%), tonsillar hyperemia (97.6%), presence of crypt (24.6%), and membrane over tonsils (1%). Group A beta-hemolytic streptococcocci were detected in the throat swab cultures of 66 (%13.2) patients. Genotypically toxin negative C.diphtheriae biovar gravis was identified in the throat swab cultures of 3 patients (2 girls and 1 boy). The tonsils were hyperemic and hypertrophic in all the patients with C.diphtheriae biovar gravis. C.ulcerans and C.pseudotuberculosis were detected in none of the patients. It is considered that similar regular cross-sectional studies or routine screening programs are expected to raise awareness about this forgotten microorganism both epidemiologically and microbiologically.

Quantitative Proteomic Analysis Reveals Changes in the Benchmark Corynebacterium pseudotuberculosis Biovar Equi Exoproteome after Passage in a Murine Host.

Corynebacterium pseudotuberculosis biovar equi is the etiologic agent of ulcerative lymphangitis. To investigate proteins that could be related to the virulence of this pathogen, we combined an experimental passage process using a murine model and high-throughput proteomics with a mass spectrometry, data-independent acquisition (LC-MSE) approach to identify and quantify the proteins released into the supernatants of strain 258_equi. To our knowledge, this approach allowed characterization of the exoproteome of a C. pseudotuberculosis equi strain for the first time. Interestingly, the recovery of this strain from infected mouse spleens induced a change in its virulence potential, and it became more virulent in a second infection challenge. Proteomic screening performed from culture supernatant of the control and recovered conditions revealed 104 proteins that were differentially expressed between the two conditions. In this context, proteomic analysis of the recovered condition detected the induction of proteins involved in bacterial pathogenesis, mainly related to iron uptake. In addition, KEGG enrichment analysis showed that ABC transporters, bacterial secretion systems and protein export pathways were significantly altered in the recovered condition. These findings show that secretion and secreted proteins are key elements in the virulence and adaptation of C. pseudotuberculosis. Collectively, bacterial pathogenesis-related proteins were identified that contribute to the processes of adherence, intracellular growth and evasion of the immune system. Moreover, this study enhances our understanding of the factors that may influence the pathogenesis of C. pseudotuberculosis.

Corynebacterium species nasopharyngeal carriage in asymptomatic individuals aged ≥ 65 years in Germany.

PURPOSE: The prevalence of protective anti-diphtheria toxin antibodies decreases with age. Therefore, the elderly might serve as reservoir for potentially toxigenic Corynebacterium (C.) species (C. diphtheriae, C. ulcerans, and C. pseudotuberculosis). This study aimed to examine the colonization rate of the nasopharynx with corynebacteria of individuals aged 65 years and older. METHODS: In the period from October 2012 to June 2013, nasal and throat swabs were taken from 714 asymptomatic subjects aged 65-106 years (average age 77.2) at three regions in Germany and investigated for Corynebacterium species. RESULTS: A total of 402 strains of Corynebacterium species were isolated from 388 out of 714 asymptomatic subjects (carriage rate 54.3%). The carriage rate was significantly higher in study participants living in retirement homes (68.4%) compared to those living autonomously at home (51.1%). Strains were isolated mostly from the nose (99%). Corynebacterium accolens was the most often isolated species (39.8%), followed by C. propinquum (24.1%), C. pseudodiphtheriticum (19.4%), and C. tuberculostearicum (10.2%). No C. diphtheriae, C. ulcerans, and C. pseudotuberculosis strains were isolated. A subsample of 74 subjects was tested serologically for anti-diphtheria antibodies. Protective anti-diphtheria toxin antibodies were found in 29.7% of the subjects; 70.3% showed no protective immunity. CONCLUSIONS: These results suggest that carriage of potentially toxigenic corynebacteria is very rare among people aged 65 and older in Germany. However, the low prevalence of protective anti-diphtheria toxin antibodies might pose a risk for acquiring diphtheria especially for the elderly.

Comparative genomic analysis between Corynebacterium pseudotuberculosis strains isolated from buffalo.

Corynebacterium pseudotuberculosis is a Gram-positive, pleomorphic, facultative intracellular pathogen that causes Oedematous Skin Disease (OSD) in buffalo. To better understand the pathogenic mechanisms of OSD, we performed a comparative genomic analysis of 11 strains of C. pseudotuberculosis isolated from different buffalo found to be infected in Egypt during an outbreak that occurred in 2008. Sixteen previously described pathogenicity islands (PiCp) were present in all of the new buffalo strains, but one of them, PiCp12, had an insertion that contained both a corynephage and a diphtheria toxin gene, both of which may play a role in the adaptation of C. pseudotuberculosis to this new host. Synteny analysis showed variations in the site of insertion of the corynephage during the same outbreak. A gene functional comparison showed the presence of a nitrate reductase operon that included genes involved in molybdenum cofactor biosynthesis, which is necessary for a positive nitrate reductase phenotype and is a possible adaptation for intracellular survival. Genomes from the buffalo strains also had fusions in minor pilin genes in the spaA and spaD gene cluster (spaCX and spaYEF), which could suggest either an adaptation to this particular host, or mutation events in the immediate ancestor before this particular epidemic. A phylogenomic analysis confirmed a clear separation between the Ovis and Equi biovars, but also showed what appears to be a clustering by host species within the Equi strains.

Corynebacterium pseudotuberculosis Infection in Patagonian Huemul ( Hippocamelus bisulcus ).

Corynebacterium pseudotuberculosis is an intracellular bacteria and the etiologic agent of caseous lymphadenitis in domestic and wildlife species. We report C. pseudotuberculosis infection in Patagonian huemul ( Hippocamelus bisulcus ) from the Cerro Castillo National Reserve, Region of Aysen, Chile. Subcutaneous abscesses in the abdominal and pectoral regions from two animals were sampled and bacteriologic isolation was performed. In both cases, we isolated a C. pseudotuberculosis strain belonging to the ovine genotype. In addition, one isolate was resistant to ciprofloxacin and streptomycin. We report that H. bisulcus is a susceptible species to this bacterium, which is transmitted by direct or indirect contact with domestic sheep ( Ovis aries ) and which represents a potential conservation threat to populations of H. bisulcus . Additional research and prevention efforts should be addressed.