Relationships between antimicrobial resistance, distribution of virulence factor genes and the origin of Trueperella pyogenes isolated from domestic animals and European bison (Bison bonasus).

Trueperella pyogenes is an opportunistic pathogen causing suppurative infections in livestock and wild animals. Although this bacterium is known for a long time, our knowledge about its pathogenicity is still insufficient. In this study the relationships between antimicrobial resistance profiles, distribution of virulence factor genes and the origin of T. pyogenes isolates were investigated. Isolates (n = 97) from various infections in domestic animals and European bison were studied. Minimal inhibitory concentrations of 12 antimicrobials were determined by a strip diffusion method, and PCR was used for detection of genes encoding seven putative virulence factors. All strains were susceptible to tested beta-lactams, and a statistically significant correlation between the resistance to enrofloxacin, tetracycline, macrolides, clindamycin, and a strain origin was found. The isolates from European bison were more susceptible than those from livestock, however the resistance to tetracycline and fluoroquinolones was observed. The plo and fimA genes were detected in all strains. There was no statistically significant association between the distribution of particular virulence factor genes and the type of infection, but the nanH, nanP and fimG genes were less frequently found in the isolates from European bison. The presence of three genes, nanP, nanH and cbpA, was found to be related to the resistance to tetracycline and ciprofloxacin. In conclusion, the resistance patterns of T. pyogenes were correlated with an isolate origin, but our findings did not allow to indicate which of the putative virulence factors may play a crucial role in the pathogenesis of particular types of T. pyogenes infection.

Dynamics of uterine infections with Escherichia coli, Streptococcus uberis and Trueperella pyogenes in post-partum dairy cows and their association with clinical endometritis.

The diversity and dynamics of the uterine microbiota of dairy cows are poorly understood although it is becoming increasingly evident that they play a crucial role in the development of metritis and endometritis. Fourier-transform infrared (FTIR) spectroscopy was used to monitor the bovine microbiota of 40 cows on the day of calving and days 3, 9, 15, and 21 after parturition, and to investigate the associations of selected species with clinical endometritis (CE). Trueperella pyogenes (43.5%), Escherichia coli (21.5%), Bacillus spp. (21.0%) and Streptococcus uberis (18.5%) were the most frequently isolated microbes. Analyses of different sampling time points revealed that the presence of S. uberis on day 3 increased the risk of subsequent T. pyogenes infection on day 9 (odds ratio [OR] = 5.1, 95% confidence interval [CI] = 1.2-22.6). T. pyogenes infection (OR = 36.0, 95% CI = 3.8-343.2) and retained fetal membranes (RFM) (OR = 12.4, 95%CI = 1.4-112.7) were significant risk factors for CE. Cows with S. uberis on day 3 tended to have greater odds of CE than S. uberis-negative cows (OR = 7.1, 95% CI = 0.9-55.6). Chemometric analysis revealed significant differences in the metabolic profile of S. uberis strains isolated from cows with different vaginal discharge scores. This is the first study showing the association of specific S. uberis subtypes with the uterine health status of post-partum dairy cows. The study demonstrates that uterine clearance is a highly dynamic process, during which time bacteria show distinct patterns of progression, and provides information about interactions between bacterial species involved in the occurrence of CE.

Uterine response to multiple inoculations with Arcanobacterium pyogenes and Escherichia coli in nulliparous ewes.

PROBLEM: Uterine infections seem more severe in nulliparous animals. Our objective was to determine whether intrauterine inoculation of nulliparous ewes with Arcanobacterium pyogenes and Escherichia coli would produce an antibody response and reduce the severity of subsequent infections. METHOD OF STUDY: Nulliparous ewes (n = 9/treatment) received (i) 'primary intrauterine inoculation' with phosphate-buffered saline (PBS) and 'secondary intrauterine inoculation' with PBS; (ii) primary PBS-secondary 75 x 10(7) cfu of A. pyogenes and 35 x 10(7) cfu of E. coli (PBS-Bacteria); (iii) primary bacteria-secondary PBS; or (iv) primary bacteria-secondary bacteria (Bacteria-Bacteria). RESULTS: Inoculations evoked an antibody response. Postmortem examinations 6 days after the secondary inoculation indicated that PBS-treated ewes did not develop uterine infections, but all bacteria-treated ewes did. Infections were either less severe or closer to resolution in Bacteria-Bacteria than they were in PBS-Bacteria ewes. CONCLUSIONS: Intrauterine inoculation of nulliparous ewes with A. pyogenes and E. coli evokes an antibody response that may help the uterus reduce the severity of subsequent infections.

Morbidity and mortality associated with Arcanobacterium pyogenes in a group of captive blackbuck (Antilope cervicapra).

Arcanobacterium pyogenes was associated with necrotizing pneumonia; mandibular osteomyelitis; peritonitis; and hepatic, pulmonary, renal, and subcutaneous abscessation in a group of captive blackbuck (Antilope cervicapra). Males were more frequently (73.3%) affected than females. Infection with A. pyogenes was fatal or necessitated euthanasia in 15 of 16 (93.7%) cases. Deaths associated with A. pyogenes occurred most frequently (60%) during winter.

Ulcerative balanitis and vulvitis of Dorper sheep in South Africa: a study on its aetiology and clinical features.

Ovine ulcerative balanitis and vulvitis in sheep of the Dorper breed has been observed in South Africa since 1979. Its aetiology has not been conclusively resolved, and there is some discrepancy in descriptions of its clinical features. In order to identify the pathogenic micro-organism/s that contribute to the occurrence of the disease, the microflora in the genital tracts of both clinically healthy and affected sheep were isolated and compared. Bacteriological examination of materials from affected and unaffected sheep resulted in the isolation of Arcanobacterium pyogenes from 44.2% and 17.2% of them respectively. This difference is statistically significant (P < 0.01). Seventy-four per cent of the isolates originated from severe clinical cases. Mycoplasmas were isolated from 49.3% of 116 clinically normal sheep and 78.2% of 104 affected sheep. There were significant differences in their rates of isolation in clinical groups (P < 0.05). Of all the mycoplasma isolates, Mycoplasma mycoides mycoides large colony variant (MmmLC) was isolated from 61.5% of clinically diseased sheep while 6.0% of the isolates were from apparently healthy animals (P < 0.05). The study threw light on the prevalence of mycoplasmas in the genital tract of apparently healthy sheep and, at the same time the identity of the mycoplasma pathogen associated with ulcerative balanitis and vulvitis was revealed. The findings of this investigation therefore confirmed the involvement of mycoplasma, particularly that of MmmLC large colony, in the disease in Dorper sheep in South Africa, and it was concluded that this microorganism is an important pathogen of balanitis and vulvitis in them. The study furthermore demonstrated a probable synergism between A. pyogenes and MmmLC. Finding these 2 organisms together occurred 53.4 times more frequently in the affected sheep than in the unaffected, which emphasises the probable multifactorial nature of the disease. The association between age and the presence of clinical signs was statistically significant. It was found that young sheep were more likely to have lesions than adult sheep. Clinical observations showed that the typical ulceration appears to be confined to the glans penis and lips of the vulva; no ulceration was observed on the shaft of the penis and prepuce or vaginal vestibule. In uncomplicated cases inflammation of the prepuce and vaginal vestibule is not a regular feature of the disease. Therefore the names ulcerative balanitis and vulvitis most accurately describe the nature of the disease in South Africa.

In vitro antimicrobial susceptibility of Mycoplasma mycoides mycoides large colony and Arcanobacterium pyogenes isolated from clinical cases of ulcerative balanitis and vulvitis in Dorper sheep in South Africa.

The in vitro activities of enrofloxacin, florfenicol, oxytetracycline and spiramycin were determined against field isolates of Mycoplasma mycoides mycoides large colony (MmmLC) by means of the broth microdilution technique. The minimum inhibitory concentrations (MICs) of these antimicrobial drugs were determined for a representative number of 10 isolates and 1 type strain. The susceptibility of Arcanobacterium pyogenes to enrofloxacin, oxytetracycline and tilmicosin was determined by means of an agar disk diffusion test. The MICs of enrofloxacin, florfenicol, oxytetracycline and spiramycin were within the ranges of 0.125-0.5, 1.0-2.0, 2.0-4.0 and 4.0-8.0 microg/ml, respectively. This study has shown that resistance of MmmLC against enrofloxacin, florfenicol, oxytetracycline and spiramycin was negligible. All the field strains of A. pyogenes that were tested were susceptible to enrofloxacin, oxytetracycline and tilmicosin with mean inhibition zones of 30.6, 42.3 and 35.8 mm, respectively. Although there is lack of data on in vivo efficacy and in vitro MIC or inhibition zone diameter breakpoints of these antimicrobial drugs for MmmLC, the MIC results indicate that these 4 classes of antimicrobial drugs should be effective in the treatment of ulcerative balanitis and vulvitis in sheep in South Africa.

[One case of pneumonia with Arcanobacterium pyogenes]. / A propósito de un caso de neumonía por Arcanobacterium pyogenes.

Arcanobacterium pyogenes is an anaerobic Gram-positive bacilli and it is a part of the normal flora in many domestic animals. A. pyogenes is a rare cause of pyogenic infections in humans and most of cases reported are questionable since there was failure to definitively identify the pathogen. A man with no past medical history presented with respiratory infection. The blood sample collected confirmed an Arcanobacterium pyogenes. It was necessary the addition of clarytromycin to the initial empirical treatment with cefotaxime, to the complete recovery. This case provide further evidence that A. pyogenes can be a pathogen in humans even in absence of predisposing illness.

Experimentally induced orchitis associated with Arcanobacterium pyogenes: clinical, ultrasonographic, seminological and pathological features.

The objectives of this study were to describe the features of experimentally induced orchitis associated with Arcanobacterium pyogenes and confirm the pathogenicity of the organism for the ovine testicle. One testicle of each of nine rams was inoculated with 1.3 +/- 10(4) colony-forming-units of an A. pyogenes isolate and regular clinical, ultrasonographic, bacteriological and seminological examinations were carried out up to 204 days after challenge. The rams were sequentially euthanatized 3, 6, 9, 18, 30, 50, 71, 113 and 204 days after challenge and a gross- and histopathological examination of their testicles was performed. All rams developed clinical orchitis and general signs. The initial ultrasonographic findings were changes of size and echogenicity of the genitalia, whilst in the long-standing phase they were wider appearance of the mediastinum testis, presence of hyperechogenic foci, changes of echogenicity of the genitalia and increased echogenicity of the scrotum and tunics. The following changes in semen evaluation parametres were recorded: the pH, the percentage of dead sperms, the percentage of abnormal sperms and the number of nonsperm round cells increased, whilst the mass motility, the individual motility and the sperm concentration decreased; the following sperm defects were observed: misshapen or piriform heads, sperms with coiled tails, sperms without tail and sperms with proximal cytoplasmic droplet; at the early stages neutrophils were the prevailing nonsperm round cell type, later the proportion of immature germ cells increased and in the long-standing phase there were enlogated spermatids and leucocytes; it is noteworthy that semen evaluation parametres were restored to normal at the late stages of the disease. A. pyogenes was consistently isolated from the semen samples after challenge, as well as from the dissected genitalia. The salient post-mortem findings were: initially, subcutaneous oedema, fluid into the vaginal cavity, congested and distended vessels, increased size of the genitalia and a hard dark area inside the testicles; subsequently, there were changes of size of the genitalia, thickening of scrotum and tunics and presence of fibrin on the testicular surface; in the long-standing phase of the disorder, there were induration of scrotum and tunics with adhesion between the tunics and discolouration of the surface of the genitalia. The prominent histopathological changes were observed in the inoculated testicles; milder changes were seen in the respective epididymides; interstitial oedema, diffuse neutrophilic infiltration and extravasation were observed in the early stages after challenge; lymphocytic infiltration with concurrent fibrosis, mineralization and inspissation of the tubular elements of the seminiferous tubules and presence of vacuolated Sertoli cells were seen later; finally, regeneration of the epithelium and presence of Sertoli cells and spermatogonia with various degrees of spermatogenic activity were evident. These findings, allied to the isolation of A. pyogenes from field cases of ovine orchitis, provide clear evidence that A. pyogenes is pathogenic for the ovine genitalia; however, the mechanisms of transition of the organism from commensal to pathogenic state are not clear. It is also noteworthy that some degree of fertility was restored in the late stages of the disorder. Ultrasonography appeared to be useful for the diagnosis of intra-scrotal abnormalities, especially during investigation of the long-standing stage of the disease, after clinical findings have subsided.

A propósito de un caso de neumonía por Arcanobacterium pyogenes / One case of pneumonia with Arcanobacterium pyogenes

Arcanobacterium pyogenes es un bacilo anaerobio Gram positivo perteneciente a la flora habitual de muchos animales domésticos. Las infecciones por Arcanobacterium pyogenes son extremadamente infrecuentes en humanos y la mayoría de casos publicados son cuestionados dado que no consiguen identificar claramente al patógeno. Presentamos el caso de un varón sin antecedentes clínicos de interés con infección respiratoria y hemocultivos positivos confirmados para Arcanobacterium pyogenes. Fue necesaria la combinación de claritromicina y cefotaxima para conseguir la curación del paciente. Este caso muestra la capacidad del A. pyogenes para provocar infecciones severas en humanos incluso en ausencia de enfermedades predisponentes (AU)

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The gene encoding pyolysin, the pore-forming toxin of Arcanobacterium pyogenes, resides within a genomic islet flanked by essential genes.

The plo gene, encoding the Arcanobacterium pyogenes cholesterol-dependent cytolysin, pyolysin (PLO), was localized to a 2.7-kb genomic islet of reduced %G+C content and alternate codon usage frequency. This islet, conserved among isolates from diverse hosts and geographical locations, separated the housekeeping genes smc and ftsY, which are found adjacent in many prokaryotes. The ftsY and ffh genes, located downstream of the plo islet, encode components of the signal recognition particle. Mutational analysis suggested that these genes were essential for viability in A. pyogenes. The A. pyogenes ffh gene was unable to complement a conditional ffh mutant of Escherichia coli and its overexpression was toxic in E. coli. Mutagenesis of the islet-encoded orf121 did not affect plo expression, indicating that it may not be involved directly in the regulation of plo expression. Regardless, the presence of the plo gene as part of a genomic islet inserted between genes essential for normal growth may provide selective pressure for the retention of this important virulence factor.

Effect of unilateral, intraovarian infusions of bacteria on ovarian morphology in gilts.

The aim of this study was to investigate whether unilateral, intraovarian infusions of bacteria might have induced morphological changes in the contralateral ovary. Eleven sexually matured gilts with controlled estrous cycle were used. The animals were randomly divided into two groups: I (Gr. I, treated; n = 4), and II (Gr. II, control; n = 7). In Gr. I, 1 ml of bacterial suspension (10(3) colony forming units/ml of saline of Escherichia coli, Staphylococcus aureus and Corynebacterium pyogenes, in proportion 1:1:1) was infused into the hilus of one ovary from the 15th to the 19th day of the estrous cycle. At the same time, 1 ml of saline was infused into the hilus of the contralateral ovary and into both ovaries of the control gilts. On the 7th day of the next cycle, the ovaries were dissected out. There were no significant differences in the number of follicles and corpora lutea (CL) as well as in weight and size between the bacteria-infused, contralateral and control ovaries. The microscopic observations of the bacteria-infused ovaries revealed the presence of focal infiltrations of neutrophils in the softened stroma, especially around dilated blood vessels filled with erythrocytes. In the contralateral ovaries, the number of regularly distributed neutrophils in the softened stroma was greater than that found in the bacteria-treated ovaries. CL of the bacteria-infused ovaries had more numerous, dilated blood vessels than CL observed in the contralateral gonads. More neutrophils were found in CL of both ovaries in Gr. I as compared to those observed in Gr. II. In Gr. II, single neutrophils were found also in the stroma where the tip of the cannula was inserted. This study revealed that in gilts, unilateral, intraovarian administration of bacteria did not change the number of ovarian structures, the weight and size of the bacteria-infused and contralateral ovary, but induced inflammatory changes in both ovaries.

Evaluation of the pathology, pathogenesis and aetiology of auricular elephantiasis in slaughter pigs.

Ears from slaughter pigs with auricular elephantiasis (n = 24) and the corresponding lymph nodes (lnn.) (n = 26) were grossly, histopathologically and microbiologically examined. Immunostaining for IgM, IgG, Cd3epsilon and bacterial antigens of Arcanobacterium pyogenes and Staphylococcus aureus was performed by indirect enzyme-based techniques. Ears were variably thickened depending on the sampled area (basis, centre and apex). However, at all locations the thickness, the length from basis to apex and the weigh of whole ears with elephantiasis were significantly increased (P < 0.01). The corresponding lnn., that is, ln. parotideus superficialis and profundus, had also increased significantly (P < 0.01) in volume. Histopathologically, lesions of the ears and the corresponding lnn. revealed changes characterized by diffuse fibrosis intermingled with multiple pyogranulomatous foci containing asteroid bodies. In the majority of lesions, four distinct zones due to different cellular infiltrates encircled the central core of the asteroid bodies. In several lesions, the pyogranulomatous foci were contained within the lymph vessels. Immunohistochemically, only the bacterial antigen of S. aureus was detected within the cytoplasm of the macrophages and/or in the asteroid bodies of the ears (41.5%) and in the regional lnn. (30.8%). An abundant number of IgM, IgG and CD3epsilon-positive cells were present in all the pyogranulomatous lesions, whereas a positive IgG-staining was observed only in a single asteroid body. Thus, porcine auricular elephantiasis is a chronic pyogranulomatous inflammation that is frequently positive for S. aureus and is lymphogenically spread. Therefore, the lesions of the ears with auricular elephantiasis and the corresponding lnn. should be termed auricular botryomycosis and botryomycotic lymphadenitis, respectively. Moreover, as the disease is observed frequently in slaughter pigs it must also be considered according to the welfare of the animals and in relation to post-mortem meat inspection.

Actinomyces pyogenes septic arthritis in a diabetic farmer.

We report a case of septic arthritis and osteomyelitis of the left ankle due to Actinomyces pyogenes in a diabetic farmer. Few confirmed human cases of A. pyogenes infection have been reported, partly because of inadequate identification of this bacterium. Bacteriological characteristics of the organism, which resembles Arcanobacterium haemolyticum, are described with a review of previous case reports.

Incidence, location and interrelationships between the sites of abscesses recorded in pigs at a bacon factory in Northern Ireland.

The position and incidence of all the abscesses detected during post mortem inspection of 75,130 bacon weight pigs were recorded. Abscesses were detected at one site only in 2.87 per cent of the carcases examined, and at more than one site in 0.26 per cent of the carcases. Tail biting was the cause of the infection in 61.7 per cent of all the carcases with lesions at more than one site. In almost all cases there was a statistically significant interrelationship between the visible abscesses at different sites.

First observation of camel (Camelus dromedarius) lymphadenitis in Libya. A case report.

The clinical signs of lymphadenitis in camels in Libya were investigated. Four animals 6 to 8 years old were inappetent, emaciated and slightly anemic. The disease was characterized by swelling and abscess formation in the inferior cervical lymph nodes at the base of the neck. Corynebacterium pyogenes was the causative microorganism of this diseased condition.

Isolation of gram-positive rods that resemble but are clearly distinct from Actinomyces pyogenes from mixed wound infections.

Beginning in 1990, gram-positive rods resembling Actinomyces pyogenes were found with increasing frequency in mixed cultures from various infectious processes, most of them from patients with otitis, empyema, pilonidal cysts, perianal abscesses, and decubitus ulcers. Ribotyping and hybridization showed that these gram-positive rods could be divided into five groups not related to known Actinomyces species. Biochemical markers for reliable differentiation into these groups, however, could not be found. Therefore, naming new species is not warranted unless parameters are discovered that allow identification without DNA hybridization. These gram-positive rods have been isolated only in mixed cultures with anaerobes, Staphylococcus aureus, Streptococcus "milleri," enterococci, and gram-negative rods. Their exact role in these possibly synergistic infections needs further investigation.

Severe complications induced by experimental bacterial superinfection of orf lesions.

Twelve goats about 3 months of age were divided into 4 equal groups. Goats in Groups 1 and 2 were infected with orf virus followed by Corynebacterium pyogenes infection of Groups 1 and 3, 3 days after the first appearance of orf lesions. Goats in Group 4 were uninfected controls. Complicated orf lesions which consisted of wet suppurative scabs around the entire lips were observed in goats in Group 1. The lesions persisted for 24 days but were most severe from days 8 to 13. Goats in Group 2 developed lesions typical of orf virus infection that lasted 10 days, while goats in Group 3 developed small nodules of about 1 cm diameter, 48 hours following the introduction of C. pyogenes, which persisted for only 6 days. No lesion was observed in goats in Group 4. Two goats in Group 1 with complicated orf died after 16 and 22 days respectively.

Human infections with Actinomyces pyogenes (Corynebacterium pyogenes).

Actinomyces pyogenes (Corynebacterium pyogenes), a well-known pathogen in many animals, was isolated from 11 Danish patients since 1968. Bacteriologic characteristics and clinical pictures of the patients are described. Ability to hydrolyze gelatine, to produce beta-glucuronidase, to reach with antisera against group-G streptococci, and to produce acid from xylose differentiates A. pyogenes from Arcanobacterium haemolyticum, with which it has at times been confused. Actinomyces pyogenes is an established, but often misrecognized, human pathogen that should be better known to clinical microbiologists.