Plasmid profiles of virulent Rhodococcus equi isolates from soil environment on horse-breeding farms in Hungary

The plasmid profiles of virulent Rhodococcus equi strains isolated on three horse-breeding farms located in different parts of Hungary were investigated. From 49 soil samples collected on the three farms, 490 R. equi isolates (10 from each sample) were obtained and tested for the presence of 15- to 17-kDa antigens (VapA) by immunoblotting and PCR. Ninety-eight VapA-positive isolates were detected from 30 of the 49 culture-positive samples with a prevalence ranging from 13.1% to 23.2%. Of the 98 virulent isolates, 70 contained an 85-kb type I plasmid, 13 contained an 87-kb type I plasmid, and 15 contained an 85-kb type III plasmid which had been uniquely isolated from soil isolates in the United States. This study demonstrates that the virulent form of R. equi is very widespread in the soil environment of these stud farms in Hungary and the plasmid pattern is different from farm to farm.

Comparison of selective media for the isolation of Rhodococcus equi and description of a new selective plating medium

In order to improve the isolation rate of Rhodococcus equi from animals and soil, the efficacy of four previously described selective media (CAZ-NB, M3T, NANAT and TINSDALE) and that of four other media (NC, PNP, TCP and TVP) composed by us was compared and evaluated. Two selective plating media proved to be the best for the isolation of R. equi from contaminated samples. One of them was CAZ-NB containing ceftazidime, novobiocin and cycloheximide, while the other was the newly composed TCP containing trimethoprim, cefoperazone, polymyxin B, cycloheximide and potassium tellurite as selective components. These two media allowed the growth of at least 62-72% of R. equi present in the artificially contaminated samples, and the inhibition of unwanted contaminant bacteria and fungi was satisfactory with both media. TCP medium proved to be superior to CAZ-NB since the colony morphology of R. equi was much more characteristic (shiny, smooth, black colonies 3-5 mm in diameter) on it, and it inhibited the unwanted contaminant bacterial and fungal flora more effectively, especially in the case of faecal and soil samples. Therefore, TCP is recommended as a new, highly selective plating medium for the isolation of R. equi from contaminated samples.

The efficacy of valnemulin (Econor) in the control of disease caused by experimental infection of calves with Mycoplasma bovis

Mycoplasma bovis infection was experimentally induced in groups of six young calves. A further group was uninfected and served as a control. Ten days after infection, medication with either enrofloxacin (Baytril, Bayer) or valnemulin (Econor, Novartis) was instituted via the milk replacer for a further 10 days, after which all calves were killed. Infection resulted in depression, pyrexia, inappetance and prominent respiratory signs. Arthritis occurred in two animals and two (unmedicated) animals died. At post-mortem examination extensive lesions were present in the lungs and M. bovis was re-isolated from infected unmedicated calves' lungs. Medication with either enrofloxacin or valnemulin resulted in a rapid diminution of clinical signs, restoration of appetite and reversal of weight loss. Isolation of Pasteurella multocida from the calves' lungs was suppressed by both medicaments. Valnemulin resulted in a more rapid reduction of clinical scores and eliminated M. bovis from the lungs more effectively than enrofloxacin.

Endothelial nitric oxide synthase gene interactions and the risk of ischaemic stroke

OBJECTIVE

Endothelial nitric oxide synthase (eNOS), which produces NO, plays an important role in the endothelial function under a wide range of physiological conditions. eNOS exon 7 polymorphism (Glu298Asp, G894T) has been considered to influence the risk of coronary artery disease. Alone, however, it has not been shown to be a genetic risk factor for ischaemic stroke. With the assumption of additive interactions, we examined whether the eNOS G894T or eNOS 894TT genotypes in combination with the methylenetetrahydrofolate reductase 677TT (MTHFR 677TT) or angiotensin-converting enzyme (ACE) D/D genotype could contribute to acute ischaemic stroke.

MATERIAL AND METHODS

The data on 407 consecutive patients with acute ischaemic stroke who had never suffered a previous stroke event were analysed. As a control group, 295 stroke and neuroimaging alteration-free Caucasian subjects were examined. With the use of the PCR technique, the eNOS G894T, eNOS 894TT, MTHFR 677TT and ACE D/D mutations, as unfavourable common genotypes were determined in the participants. Logistic regression models were used to evaluate the roles of the genotypes and their combinations in the development of ischaemic stroke.

RESULTS

The MTHFR C677TT genotype combined with the eNOS G894T or eNOS 894TT genotypes occurred significantly more frequently in the subjects with ischaemic stroke (7.1%; P < 0.025) than in the control group (3.1%). The co-occurrence of the ACE D/D genotype and eNOS G894T or eNOS 894TT was calculated to be more frequent in the ischaemic stroke group (20.9%, P < 0.0001) than in the control group (5.4%).

CONCLUSION

The eNOS G894T or eNOS 894TT genotypes in combination with the MTHFR 677TT or ACE D/D genotype increases the risk of ischaemic stroke.

Specific APO E genotypes in combination with the ACE D/D or MTHFR 677TT mutation yield an independent genetic risk of leukoaraiosis

OBJECTIVE

Ischaemic demyelination of the white matter of the brain is a frequent clinical entity. In the neuroimaging terms, it is referred to as leukoaraiosis. We earlier found that the co-occurrence of the homozygous methylenetetrahydrofolate reductase (MTHFR) 677TT and angiotensin-converting enzyme D/D (ACE D/D) genotypes yielded a highly significant moderate risk of leukoaraiosis. On the assumption of further genetic interactions, we have now investigated whether the different apolipoprotein E (APO E) genotypes, in pairwise combinations with the MTHFR 677TT or ACE D/D mutation, could lead to an increased risk of leukoaraiosis.

MATERIAL AND METHODS

We analysed the occurrence of the APO E genotypes in pairwise combinations with the MTHFR 677TT or ACE D/D mutation in 315 consecutive Caucasian patients with leukoaraiosis. A total of 646 neuroimaging-free subjects acted as a control group.

RESULTS

The APO E 2/2 and 2/3 or APO E 4/4 and 4/3 genotypes in combination with the MTHFR 677TT or ACE D/D mutation exhibited independent genetic risks of leukoaraiosis.

CONCLUSION

The interactions of certain unfavourable genetic mutations can contribute to the evolution of leukoaraiosis.

Evaluation of the modifying effects of unfavourable genotypes on classical clinical risk factors for ischaemic stroke

OBJECTIVES

Ischaemic stroke is a frequent heterogeneous multifactorial disease that is affected by a number of genetic mutations and environmental factors. We hypothesised the clinical importance of the interactions between common, unfavourable genetic mutations and clinical risk factors in the development of ischaemic stroke.

METHODS

The Factor V Leiden G1691A (Leiden V), the prothrombin G20210A, the methylenetetrahydrofolate reductase C677T (MTHFR C677T) mutations, the angiotensin converting enzyme I/D (ACE I/D), and apolipoprotein allele e4 (APO e4) genotypes were examined by the polymerase chain reaction (PCR) technique in 867 ischaemic stroke patients and 743 healthy controls. Logistic regression models were used to estimate the roles of the co-occurrences of the clinical risk factors and common genetic mutations in ischaemic stroke.

RESULTS

The Leiden V mutation in combination with hypertension or diabetes mellitus increased the risk of ischaemic stroke. We found synergistic effects between the ACE D/D and MTHFR 677TT genotypes and drinking or smoking. The presence of the APO e4 greatly facilitated the unfavourable effects of hypertension, diabetes mellitus, smoking, or drinking on the incidence of ischaemic stroke.

CONCLUSION

In certain combinations, pairing of common unfavourable genetic factors, which alone confer only minor or non-significant risk, with clinical risk factors can greatly increase the susceptibility to ischaemic stroke.

Association between endometritis and urocystitis in culled sows

Slaughterhouse sampling and examination of urogenital tracts of 499 sows and gilts culled for reproductive reasons from 21 Hungarian herds were performed over a 6-year period. The aim was to estimate the prevalence of different urogenital tract lesions, and to provide sensitivity and specificity estimates for macroscopic and bacteriological examinations in the diagnosis of urocystitis and endometritis. Furthermore, the association between endometritis and urocystitis was assessed. The prevalence of main lesions of the urogenital tract was similar to that reported in other studies. The 'sensitivity' of macroscopic and bacteriological methods was determined statistically by taking histopathology as the 'Gold Standard'. As a result, the 'sensitivity' of macroscopic methods for the diagnosis of endometritis and urocystitis was < or = 18.1% and 47.9%, respectively, while the 'sensitivity' of bacteriology for the diagnosis of the same conditions was < or = 31.8% and 63.0%, respectively. The presumed positive association between urocystitis and endometritis was confirmed; it was not confounded by parity. Animals affected by urocystitis had a 3.5 times higher odds to simultaneously have endometritis than animals without urocystitis.

In vitro sensitivity of Hungarian Actinobaculum suis strains to selected antimicrobials

In vitro antimicrobial sensitivity of 12 Hungarian isolates and the type strain ATCC 33144 of Actinobaculum suis to different antimicrobial compounds was determined both by the agar dilution and by the disc diffusion method. By agar dilution, MIC50 values in the range of 0.05-3.125 micrograms/ml were determined for penicillin, ampicillin, ceftiofur, doxycycline, tylosin, pleuromutilins, chloramphenicol, florfenicol, enrofloxacin and lincomycin. The MIC50 value of oxytetracycline and spectinomycin was 6.25 and 12.5 micrograms/ml, respectively. For ofloxacin, flumequine, neomycin, streptomycin, gentamicin, nalidixic acid, nitrofurantoin and sulphamethoxazole + trimethoprim MIC50 values were in the range of 25-100 micrograms/ml. With the disc diffusion method, all strains were sensitive to penicillin, cephalosporins examined, chloramphenicol and florfenicol, tetracyclines examined, pleuromutilins, lincomycin and tylosin. Variable sensitivity was observed for fluoroquinolones (flumequine, enrofloxacin, ofloxacin), most of the strains were susceptible to marbofloxacin. Almost all strains were resistant to aminoglycosides but most of them were sensitive to spectinomycin. A strong correlation was determined for disc diffusion and MIC results (Spearman's rho 0.789, p < 0001). MIC values of the type strain and MIC50 values of other tested strains did not differ significantly. Few strains showed a partially distinct resistance pattern for erythromycin, lincomycin and ampicillin in both methods.

Effect of induction of late embryonic mortality on plasma profiles of pregnancy associated glycoprotein 1 in heifers

Inoculation with Actinomyces pyogenes and administration of prostaglandin (PG)F(2alpha) were used to induce late embryonic mortality (LEM) in heifers (n=8) on Days 30-38 of pregnancy in order to compare the profile for bovine pregnancy associated glycoprotein 1 (PAG1), progesterone and 15-keto-13,14-dihydro-PGF(2alpha) (PGFM). Two pregnant heifers were used as controls. Inoculation into the uterine body caused LEM, as established by ultrasonography in each heifer within 24h of treatment. When the inoculum was injected into the first part of the cervix, LEM occurred in one of two heifers (Heifer A) between 48 and 72 h after treatment. Similarly, PGF(2alpha) treatment caused LEM in three of four heifers. In six of eight heifers, PAG1 started to decrease steadily when it was accompanied by the subsequent death of the embryo. Inoculation through the cervix caused luteolysis in three of four heifers within 6-10 days after induction. After induction of LEM, PGFM concentrations showed a two to 3.8 fold increase in three of four heifers during the following six days, and from that time changed within normal ranges. The results of this study indicate that a PAG1 assay may provide an alternative method to ultrasonography for determining LEM in the cow.

Clinical signs and mortality caused by Ornithobacterium rhinotracheale in turkey flocks

Upper respiratory tract disease (manifesting itself in rhinitis, tracheitis and conjunctivitis) and mortality associated with Ornithobacterium rhinotracheale infection were observed in four flocks of 2- to 3-week-old turkeys. In a 15- to 16-week-old turkey flock bilateral catarrhal-croupous pneumonia was found in the dead birds. In a further 5-week-old flock and in three 16- to 20-week-old turkey flocks mortality was preceded by nervous signs (motor disturbances, recumbency, abnormal carriage of the head) and was found to be associated with fibrinopurulent inflammation of the cranial bones and meningitis. The bacterium O. rhinotracheale was isolated from the affected organs in the different disease conditions. The isolated strains did not differ markedly in cultural, morphological and biochemical properties. This is the first report of a turkey disease manifesting itself in nervous signs associated with O. rhinotracheale infection.

Characterization of virulence plasmid types in Rhodococcus equi isolates from foals, pigs, humans and soil in Hungary

Rhodococcus equi isolates (204) obtained from foals (lung abscesses, lymph nodes, nasal discharge, rectal swabs) bred in 15 studs located throughout Hungary, isolates from soil samples, lymph nodes of pigs and from lesions of human patients were examined to determine genotypic diversity of virulence-associated plasmids. Isolates were tested for the presence of 15-17 kDa virulence-associated protein antigen (VapA) and 20k Da (VapB) genes by polymerase chain reaction (PCR). Plasmid DNAs were isolated and analysed by digestion with restriction endonucleases for estimation of size and comparison of polymorphisms. Of 146 clinical isolates from foals in 15 studs, 129 (88.3%) gave positive results for the VapA gene, showing a 564 bp product of the expected size in the PCR amplification. Of the 129 clinical isolates from foals, 123 contained an 85 kb type I plasmid and the remaining six contained an 87 kb type I plasmid. Of 48 soil isolates from two horse studs, 26 (54.2%) were positive for VapA gene and contained an 85 kb type I plasmid. Of three pig isolates, one was positive for VapA gene and contained an 85 kb type I plasmid, and the remaining two were positive for the VapB gene, showing a 827 bp product of the expected size in the PCR amplification and were R. equi of intermediate virulence which contained a 95 kb type S5 plasmid. Of the seven human isolates, five were positive for VapB gene by PCR, these were R. equi of intermediate virulence, which contained a 95 kb type S5 plasmid. These results revealed that virulent R. equi strains harbouring a virulence plasmid of 85 kb type I or 87 kb type I, which have been found in clinical isolates from Europe and North and South America, are widespread in Hungary. Furthermore, same intermediately virulence plasmid type was found in both human and pig isolates.

Evaluation of the roles of common genetic mutations in leukoaraiosis

OBJECTIVES

Leukoaraiosis, a relatively frequent neuroimaging entity, is presumed to be primarily a vascular problem. However, it can be explained only in part by vascular risk factors. With the assumption of genetic susceptibility, the roles of common genetic polymorphisms and mutations in leukoaraiosis were examined in this study.

MATERIAL AND METHODS

A detailed clinical scrutiny of 843 Hungarian neurological patients with mild cognitive-like complaints revealed 229 subjects with leukoaraiosis that was probably vascular in origin: 143 with leukoaraiosis alone (group 1), and 86 with leukoaraiosis plus cerebral infarction (group 2). In all 229 patients, the methylenetetrahydrofolate reductase C677T (MTHFR C677T) mutation and angiotensin-converting enzyme (ACE I/D) polymorphism were examined by means of the PCR technique. The prevalences of the different genotypes for the examined mutations in the 2 groups were analysed in comparison with the data on 362 neuroimaging alteration-free subjects as controls.

RESULTS

The ACE D/D genotype (38.37%, P<0.0005; OR 2.46, 95% CI, 1.49-4.08) and ACE D allele (61%; P<0.001) were more frequent in group 2 than in the control group (20.17%; 47%). Neither the homozygous nor the heterozygous MTHFR C677T mutation alone was found to be a risk factor for leukoaraiosis. The homozygous MTHFR C677T mutation combined with the ACE D/D genotype was significantly more frequent in group 1 (11.89%, P<0.0005; OR 4.75, 95% CI, 2.12-10.65), in group 2 (12.79%, P<0.0005; OR 5.16, 95% CI, 2.12-12.6) and in combined group 1+2 (12.23%, P<0.0005; OR 4.9, 95% CI, 2.33-10.3) than in the control group (2.76%).

CONCLUSION

These data indicate that the contributions of the ACE D/D genotype and the homozygous MTHFR C677T mutation to leukoaraiosis should be taken into consideration not as major, but as additive factors. These findings draw attention to the fact that genetic polymorphisms that alone are insignificant can be risk factors for leukoaraiosis if they cluster in the same subjects.

Bicarbonate and thiocyanate ions affect the gating of gamma-aminobutyric acid(A) receptors in cultured rat cortical cells

The ionophore function of gamma-aminobutyric acid(A) (GABA(A)) receptors was studied by whole-cell patch clamp electrophysiology in primary cultures of rat cerebral cortex. Chloride ions were replaced for SCN(-) (thiocyanate) and HCO(-3) (bicarbonate) ions. The EC(50) values of the GABA(A) agonist muscimol (HCO(-3)>Cl(-)>SCN(-)) varied parallel with the free energies of dehydration of the anions, while the inhibition constants of the GABA(A) antagonist bicuculline methiodide were not affected. These findings might be relevant in the interpretation of the contribution of HCO(-3) versus Cl(-) currents to the pharmacological differences between depolarizing and hyperpolarizing GABA responses.

Treatment of pigs experimentally infected with Mycoplasma hyopneumoniae, Pasteurella multocida, and Actinobacillus pleuropneumoniae with various antibiotics

The authors have performed a comparative study of the efficacy of various in-feed medications for the treatment of 5- to 6-week-old specific pathogen-free (SPF) piglets experimentally infected on day 1 with Mycoplasma hyopneumoniae, on day 8 with Pasteurella multocida (serotype A), and on day 15 with Actinobacillus pleuropneumoniae (serotype 2). The treatment started on day 9 and continued for 12 consecutive days, then the piglets were euthanized for examination of macroscopic, histologic, and pathologic lesions and for the presence of mycoplasmas and bacteria in the lungs. Based on the results of clinical observations (respiratory signs, rectal temperature, body weight gain, and feed conversion efficiency), macroscopic and histologic lesions of the lungs, and microbiologic findings, the best results were obtained by treatment of pigs with Econor + chlortetracycline, followed by Tetramutin, Pulmotil, Cyfac, and lincomycin + chlortetracycline.

Evaluation of the roles of the Leiden V mutation and ACE I/D polymorphism in subtypes of ischaemic stroke

OBJECTIVE

The Leiden V mutation, which causes activated protein C resistance and thrombophilia, has been found to be a risk factor for venous thrombosis. The angiotensin converting enzyme (ACE) D allele indirectly exerts an unfavourable effect on the vasoregulatory system. In this study, the frequency of these mutations was analysed in different subtypes of ischaemic stroke.

METHOD AND MATERIAL

According to the clinical and radiological features 664 Hungarian patients who had suffered acute ischaemic stroke were divided into 3 subtypes: small and large vessel infarcts and a mixed type. In all 664 patients, the Leiden V mutation and ACE I/D polymorphism were examined by means of the PCR technique. The frequencies of the different genotypes for the Leiden V mutation and ACE I/D polymorphism in the 3 subgroups of stroke were compared with 199 stroke-free control subjects whose MRI findings were normal.

RESULTS

No significant associations were found between the overall group of cerebral infarctions and the Leiden V, ACE I/D and ACE D/D genotypes. The ACE D/D genotype was significantly more common in the patients with small deep infarcts (40.3%; p < 0.0005; OR 2.31, 95% CI 1.49-3.57) than in the control group (22.6%). The Leiden V mutation was significantly more common in patients with large infarcts (13.6%; p < 0.025; OR 2.25, CI 1.16-4.34) than in the stroke-free control subjects (6.5%).

CONCLUSIONS

The ACE D/D genotype possibly contributes to the occurrence of small-vessel infarcts rather than large vessel infarcts. The Leiden V mutation might predispose to large brain infarcts. Neither the Leiden V factor nor the ACE D/D genotype has been proved to be a risk factor for ischaemic stroke as a whole.

Characterisation of some Ornithobacterium rhinotracheale strains and examination of their transmission via eggs

The biochemical characteristics and antibiotic susceptibility of 12 Ornithobacterium rhinotracheale strains isolated from chickens and turkeys suffering from respiratory clinical signs and the survival of some isolates on egg-shell and within chicken eggs during hatching were examined. All O. rhinotracheale strains showed typical biochemical characteristics. Among the 16 drugs examined, penicillin G, ampicillin (MICs ranging from < or = 0.06 microgram/ml to 1 microgram/ml), ceftazidim (with MICs from < or = 0.06 microgram/ml to 0.12 microgram/ml), erythromycin, tylosin, tilmicosin (with some exceptions MICs ranged from < or = 0.06 microgram/ml to 1 microgram/ml) and tiamulin (MICs varied from < or = 0.06 microgram/ml to 2 micrograms/ml) were the most effective. Lincomycin, oxytetracycline and enrofloxacin also gave good inhibitions, but with most strains in a higher concentration (MICs ranged in most cases from 2 micrograms/ml to 8 micrograms/ml). The other antibiotics inhibited the growth of O. rhinotracheale only in very high concentrations (colistin) or not at all (apramycin, spectinomycin, polymyxin B). At 37 degrees C, O. rhinotracheale did not survive on egg-shell for more than 24 hours, while upon inoculation into embryonated chicken eggs it killed embryos by the ninth day, and from the 14th day post-inoculation no O. rhinotracheale could be cultured from the eggs at all. These results suggest that O. rhinotracheale is not transmitted via eggs during hatching.

DNA sequence of a small, unidentified plasmid isolated from a Haemophilus somnus strain: short communication

One of the plasmids present in a Haemophilus somnus strain isolated from nasal discharge of a cattle with respiratory disease was purified and cloned for DNA sequencing. The plasmid was found to be 1065 base pairs long with 39.2% G + C content, and showed no homology to any DNA sequenced so far. It has no capacity to code any protein longer than 43 residues. It is not clear yet if this plasmid codes Haemophilus somnus specific factors.

Characterisation of Rhodococcus equi strains isolated from foals and from immunocompromised human patients

The cultural, morphological, biochemical, serological characteristics and antibiotic susceptibility of 25 Rhodococcus equi strains isolated from lungs and lung abscesses of pneumonic foals and 5 R. equi strains isolated from immuno-compromised human patients were examined. All R. equi strains showed common cultural, morphological and biochemical characteristics both with conventional tests and on the basis of their enzyme profile. The R. equi strains examined were resistant to penicillins with the exception of ampicillin, to sulphamethazine and several strains also to sulphamethoxazole-trimethoprim. All strains were susceptible to erythromycin and rifampicin. The strains isolated from humans showed somewhat higher rate of antibiotic resistance to penicillin, cefotaxime, kanamycin, streptomycin, lincomycin, and oxytetracycline. The overwhelming majority (96%) of the equine isolates belonged to serotype 1 in Prescott's serotyping system, while the human isolates could not be serotyped.

A clustering of unfavourable common genetic mutations in stroke cases

OBJECTIVES

The aetiological role of common genetic mutations was analysed in a subgroup of stroke patients.

MATERIAL AND METHODS

A total of 406 patients were examined because of ischaemic stroke. After a detailed clinical scrutiny, 5 were found who did not exhibit any of the classical clinical risk factors. In this clinically homogeneous subgroup of stroke patients, the prothrombin A20210G, Hong Kong, Cambridge and methylenetetrahydrofolate reductase C677T (MTHFR C677T) mutations, angiotensin-converting enzyme polymorphism (ACE polymorphism) and apolipoprotein E (APO E) genotype were examined.

RESULTS

In all 5 patients, the same type of clustering of three mutations was manifested. A heterozygous Leiden V mutation was observed in all 5 subjects, while a heterozygous MTHFR C677T mutation and an I/D genotype for ACE polymorphism were detected in 4 of them, and a homozygous D/D genotype and a homozygous MTHFR C677T mutation in 1. This type of clustering of the mutations was not observed in the remaining 401 stroke patients.

CONCLUSION

These results suggest that the Leiden mutation might possibly be an aetiological factor for stroke in a rare subgroup of patients who do not display any of the classical risk factors. The roles of ACE D polymorphism and the MTHFR C677T mutation in stroke, should also be taken into consideration in this subgroup of stroke patients. These unfavourable genetic factors might be aetiological factors if they are clustered together in a stroke patient not presenting any of the standard clinical risk factors.

[Characterization of Ru(bpy)(3)2+ and Ru(phen)(3)2+ complexes with silver(i) ion of ground state in propylene-carbonate]

Phosphorescent bimolecular and termolecular exciplexes of 3Ru(bpy)(3)2+ and Ru(phen)(3)2+ (bpy = 2,2'-bipyridine, and phen = 1,10-phenathroline) formed by silver ions of ground state in propylene carbonate solution are identified and characterized. Formation constants, lifetime, radiative and non-radiative decay constats of exciplexes are determined. Temperature-dependent luminescence lifetime measurements have revealed that exciplex formation causes a decrease in the energy level of the luminescent excited state.

Actinomycosis of dogs caused by Actinomyces hordeovulneris

Actinomyces hordeovulneris was isolated from the lesions of chronic pyogranulomatous pleuritis and pericarditis of one of three dogs showing similar symptoms. The parietal pleura and the pericardium were thickened and covered with fine short threads of angiofibroblastic tissue. About 500-1000 ml of reddish purulent exudate in the thorax of all three dogs contained large numbers of rice-grain-sized, soft, yellowish-white granules ("sulphur granules"). These granules had a central core of branching filaments of gram-positive bacteria embedded in thick granulation tissue. The parietal pleura, the mediastinal pleura and the pericardium were infiltrated mainly with neutrophils, and to a lesser extent with lymphocytes and plasma cells. A small number of eosinophils and giant cells was also observed. Large numbers of pyogranulomas embedded in the granulation tissue were composed of a core of necrotized granulation tissue, mixed with clusters of gram-positive branching bacteria, surrounded by an area of intact and degenerating neutrophils and lymphocytes. Bacteria were detected in the lesions by Brown-Brenn staining and were isolated from one of the affected animals. The isolated bacteria were identified as A. hordeovulneris. This was the first isolation of A. hordeovulneris in Hungary.