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B Skalka

Publications and source records attributed to B Skalka.

At least 19 recordsLinked to original sources
PubMed2001

[Detection of Arcanobacterium haemolyticum phospholipase D neutralizing antibodies in patients with acute tonsillitis].

Neutralization test carried on a non-nutrient blood agar prepared from sheep erythrocytes sensibilized with equi factor of Rhodococcus equi was used for the detection of antibodies against phospholipase D (PLD) of Arcanobacterium haemolyticum. Altogether, 433 sera from 404 patients aged 1 to 25 years with the signs of acute tonsillitis were examined. Antibodies against PLD were found in 28 patients (6.9%). In 116 sera from persons without the signs of tonsillitis the antibodies against PLD were detected in one case (0.9%). The titres reached the values from 4 to 64. Out of 84 paired sera, the significant change of the titre, i.e. at least the four-fold one, was observed five times: three times as the seroconversions, twice as the declines of the titre. The antibodies were found most often in children aged 11 to 15 years, 10 times out of 97 (10.3%). In 253 patients with the tonsillitis, the result of the parallel bacteriologic examinations of throat swabs was at the disposal. A. haemolyticum was successfully isolated in 3 cases, but only owing to the inhibition of staphylococcal hemolysis around its colonies. All three cases were also serologically positive. Consequently, our results show that neutralizing antibodies against PLD of A. haemolyticum can be detected in patients with tonsillitis.

Actinomycetales↗
PubMed2000

[A diagnostic medium for Arcanobacterium haemolyticum and other bacterial species reacting with hemolytic synergism to the equi-factor of Rhodococcus equi].

Colonies of Arcanobacterium haemolyticum on common blood agar can be easily overlooked. Therefore a diagnostic medium was developed, on which A. haemolyticum colonies produce a conspicuous zone of complete hemolysis. The medium under question is blood agar prepared from the Columbia Blood Agar Base and 5% washed sheep erythrocytes sensitised with equi factor (EF) of Rhodococcus equi. Optimally, 10 activity units (AU) of EF per 1 ml were used. EF was titrated on a non-nutrient medium consisting of agar Purified (Difco) and 5% washed sheep erythrocytes sensitized with beta-haemolysin (BL) of Staphylococcus aureus, 10 AU/ml. On the same medium, staphylococcal BL was titrated on the basis of its direct haemolytic effect. Despite the very distinct haemolytic reaction of the control strains evident on the diagnostic medium with EF, A. haemolyticum failed to grow from 2.597 throat swabs examined especially for the particular microbe during the a period of two years. However, A. haemolyticum was isolated on this medium twice from 223 swabs from wounds and skin lesions. The proposed medium makes also the rapid diagnosis of species Corynebacterium ulcerans, Dermatophilus congolensis and Listeria monocytogenes on the basis of haemolytic synergism possible.

Actinomycetales↗
PubMed1998

Phospholipase D-neutralization in serodiagnosis of Arcanobacterium haemolyticum and Corynebacterium pseudotuberculosis infections.

Phospholipase D (PLD) neutralization was used to examine sera of humans (n = 40) with a spontaneous infection by Arcanobacterium haemolyticum, sheep and goats (n = 76 and 79 respectively) with a spontaneous infection by Corynebacterium pseudotuberculosis, mice (n = 26) experimentally immunized with PLD from A. haemolyticum (PLD-A) and mice (n = 28) experimentally immunized with PLD from C. pseudotuberculosis (PLD-C). PLD-A and PLD-C were also used as neutralizing antigens. A positive result of neutralization was due to an inhibition of the haemolytic synergism with the equi factor from Rhodococcus equi. The titres of sera neutralizing the homologous PLD were always significantly higher than those neutralizing the heterologous PLD. The proportion of sera that were able to neutralize the homologous PLD in sheep, goats and mice immunized with PLD-A significantly exceeded the proportion of sera that neutralized the heterologous PLD. The antigenic properties of PLD-A and PLD-C were similar but not identical.

Actinomycetales↗
PubMed1998

Corynebacterium pseudotuberculosis infection in goats in the Czech Republic.

Prevalence of caseous lymphadenitis was studied in goats from six herds in the Czech Republic. Corynebacterium pseudotuberculosis exhibiting typical properties was isolated from clinically affected animals only. Antibodies to C. pseudotuberculosis were identified by means of agar immunodiffusion and the neutralization test using a toxin--phospholipase D (PLD)--as antigen. No clinical manifestations of caseous lymphadenitis or antibodies to C. pseudotuberculosis were found in four herds. In one herd without any history of clinical caseous lymphadenitis, serological positivity was reported in two out of 148 examinations. In a herd with clinical manifestations of caseous lymphadenitis, antibodies were ascertained to a various degree in subsequent samplings (100%, 87% and 64%, respectively). The importance of serologic examination of caseous lymphadenitis in goat herds is discussed.

Animals↗
PubMed1997

[Review of 105 cases of isolation of Rhodococcus equi in humans].

BACKGROUND: Rhodococcus equi (formerly Corynebacterium) has been long considered an exclusively zoopathogenic microbe causing mainly granulomatous pneumonias and lung abscesses in young foals. The aim of this paper was to analyse substantial features of R, equi infections hitherto reported in man. METHODS AND RESULTS: MEDLINE database was searched for relevant reports. When the original source was not obtained the data from reviews were employed. Together, 105 cases of R, equi infection in man were reported. Median age was 35 years with a range from 9 months to 83 years. The male: female ratio was 3.3. Lungs were involved in 72 cases (69%), extrapulmonary abscesses as the only symptom of infection were described in 9 cases, septic state in 7 cases. Clinical outcome was known in 98 cases, being fatal in 41 (42%). Therapy was mentioned in 70 reports, the most often used drugs being erythromycin (30 cases, 12 deaths), rifampicin (19 cases, 7 deaths) and vancomycin (18 cases, 6 deaths). R. equi was isolated from the sputum of 69% patients with the pulmonary involvement. Blood cultures were positive in 35% of cases. Out of total, 49% persons were HIV positive. Median age for HIV positive patients was 32 years with a range from 18 to 71 years, for HIV negative patients 52 years with a range from 9 months to 83 years. There were 97% males in the HIV positive group in contrast to 59% in the HIV negative group (p < 0.01). Lungs were involved in 90% of HIV positive and 48% of HIV negative cases (p < 0.01). Extrapulmonary abscesses as the only sign of infection were seen in 2% of HIV positive persons and in 15% of HIV negative ones (p < 0.05). Outcome was fatal for 60% of the HIV positive hosts and for 28% of the HIV negative individuals (p < 0.01). R. equi was isolated from the sputum of 80% pneumonic HIV positive patients and of 50% of pneumonic patients without HIV infection (p < 0.05). R. equi was detected in the blood of 67% of HIV positive patients and of 33% of HIV negative ones (p < 0.01). CONCLUSIONS: The analysis of published reports shows that whereas R. equi causes mainly pneumonia in persons with HIV infection, in HIV negative individuals extrapulmonary manifestations slightly prevail, most often abscesses, sepsis, eye involvement and wound infections.

AIDS-Related Opportunistic Infections↗
PubMed1997

[Rhodococcus equi--a newly recognized opportunistic pathogen in man].

The review informs about substantial features of Rhodococcus equi with emphasis on the analysis of 115 as yet published and still expanding reports on the isolation of this zoopathogenic nocardioform actinomycete from man. Microbiological laboratories of human medicine have to learn not only how to identify R. equi but also recognize it as an opportunistic pathogen in particular in persons with the deficient immunity. R. equi is a gram-positive, encapsulated diphtheroid coccobacillus, partially acid fast. It grows well on common media, its colonies being after 48 hours characteristically mucoid, coalescing, irregular and mostly lightly pinkish. Biochemically it is little active, nevertheless it causes typical synergic haemolysis of erythrocytes influenced by staphylococcal beta-toxin. R. equi is found in soil and manure, especially in horse manure. It causes above all granulomatous pneumonia in young foals. In humans, it causes mostly pneumonia and lung abscess, more frequently in persons with immunity deficiency incl. AIDS, less often extrapulmonary abscesses, sepsis and wound infections. The disease are commonly chronic and recurrent. The ability of R. equi to persist in macrophages and destroy them is important in the pathogenesis of infection. In resistance to infection the cell-mediated immunity seems to be of major importance. The port of entry are the lungs, less often the alimentary tract or injured skin. About a third of the persons gives a history of contact with animals, manure or soil. The standard treatment is prolonged administration of a combination of rifampin and erythromycin. The isolation of R. equi is easy and if a laboratory suspects the presence of this microorganism, its identification is not difficult.

Actinomycetales Infections↗
PubMed1997

[Hemolysis and hemolytic interactions of bacteria].

The review contains data on haemolytically active bacteria important in medical microbiology, human or veterinary. Attention is paid to haemolytically active bacterial metabolites, especially those which produce synergistic or antagonistic haemolytic reactions above all with staphylococcal haemolysins alpha, beta and delta, with corynebacterial phospholipase D, with rhodococcal equi factor and with the haemolysin of Dermatophilus congolensis. The general usage of the term "CAMP factor" for all manifestations of haemolytic interactions is criticized. Descriptions of haemolytic activities are supplemented by a synoptical table and most of them are documented by photographs.

Bacteria↗
PubMed1995

[Antibodies to certain infections on large goat farms in the Czech Republic].

On five newly established large goat farms the incidence of antibodies to some chronic and latent infections (arthritis and encephalitis, Q-fever, caseous lymphadenitis and toxoplazmosis) was investigated in the first six months of the year 1994. Agar-gel immunodiffusion did not reveal any antibodies to arthritis and encephalitis of goats (CAE). Complement fixation test did not demonstrate any antibodies to Q-fever. Neither agar-gel immunodiffusion nor neutralization test confirmed any antibodies to caseous lymphadentitis. Complement fixation test (titer 1:8 and more) revealed antibodies to toxoplazmosis at 20.2% of the cases. No clinical symptoms of toxoplazmosis were observed on the investigated goat farms. It was recommended to take a preventive serological examination of goats against CAE, Q-fever and caseous lymphadenitis before they were housed on the given farms. By maintaining high zoohygienic parameters on the large goat farms it is possible to except a decrease in prevalence of antibodies to toxoplazmosis.

Animals↗
PubMed1994

[Serodiagnosis of caseous lymphadenitis (pseudotuberculosis) in sheep].

Random postmortal isolation of Corynebacterium pseudotuberculosis from the sheep used in a research project and the consequently determined serological positivity of these animals indicated the serological examination of the flock from which the sheep came. No symptoms of caseous lymphadenitis were ever observed in the flock in question and no data on the occurrence of this disease were available in the flock history. The sera of 228 head of sheep were used for examinations, while this number of sheep represented half the flock head. Agar-gel immunodiffusion (AID) and neutralization of the toxin C. pseudotuberculosis (NTX) were applied as serological assays. The antigen in both tests was an isolated form of toxin i.e. phospholipase D (PLD). To determine the effect of PLD, the intensity of its synergic hemolytic effect with the equi factor Rhodococcus equi was found out and it was expressed in activity units (AU). Undiluted serum with PLD containing 5,000 AU/ml was examined in AID. Positive precipitation was observed in 79 examined sera, out of which 71 were also positive in NTX. NTX demonstrated the inhibition of synergic hemolytic activity of PLD with the equi factor, which was used to sensibilize sheep erythrocytes in agar medium. PLD with the terminal content of 10 AU/ml was used, as well as twofold dilution series of sera. The first evaluated dilution series was 1:10. In this dilution series, the highest number of sera, 22, had the positive reaction. The highest positivity at a dilution series 1:5,120 was found out in one serum. A total of 71 sera had positive reactions in NTX and those sera were also positive in AID. The determined 34.7% positivity substantiated the importance of serodiagnosis for the intravital diagnosis of caseous lymphadenitis of sheep, particularly of its chronic form. AID and NTX are usable tests for serodiagnosis of this disease.

Animals↗
PubMed1993

Antigenicity of Dermatophilus congolensis hemolysin.

The separated cell-free form of hemolytic exosubstance was obtained from five strains of Dermatophilus congolensis. Three strains produced exosubstance with high activity, two strains produced exosubstance with lower intensity of activity. The separated forms exhibited the same hemolytic interactions as the native forms produced by growing strains, namely the antagonism with staphylococcal beta hemolysin and the synergism with staphylococcal delta hemolysin, streptococcal CAMP factor and rhodococcal equi factor. Rabbit sera obtained after intravenous or intraperitoneal application of the separated forms contained precipitation and neutralization antibodies. Cross tests of precipitation and neutralization proved antigen identity of hemolysins of different D. congolensis, strains which makes the serodiagnostics of this species possible.

Actinomycetales↗
PubMed1993

[Detection of Rhodococcus equi antibodies in human serum].

The authors investigated in sera of patients with pneumonia the presence of antibodies against the equi factor Rhodococcus equi. For examination they used agar immunodiffusion and a test for neutralizing the equi factor. Some 110 sera of different donors were examined. In agar immunodiffusion they used the equi factor as antigen either in the separated form or equi factor produced by the growing strain of R. equi. The neutralization test was implemented on agar media with red blood cells sensitized with staphylococcal beta-haemolysin. In all serological tests 27 sera reacted positively only by precipitation 30 sera, while 53 sera did not contain antibodies against the equi factor. The authors discuss the impact of the assembled results and the possible participation of R. equi in human disease.

Actinomycetales Infections↗
PubMed1993

[Comparison of 2 methods of detecting slime production by coagulase-negative staphylococci].

In the series of 212 coagulase-negative staphylococci strains isolated from blood cultures, in which the slime production was tested by means of two methods--a method using agar with Congo red and a Christensen method--S. epidermidis, S. haemolyticus and S. hominis were identified most frequently (in 69.3%, 18.4% and 6.6%, respectively). The slime production was detected by both methods in 28 strains (13%) of four species, most often in S. epidermidis (in 17%). By comparing the Congo red agar method with the Christensen method the sensitivity and specificity of the former was determined (85% and 99%, respectively). Thus the Congo red agar method for the detection of slime production by staphylococci seems to be a reliable tool.

Bacteriological Techniques↗
PubMed1992

Hemolytic interactions of Dermatophilus congolensis.

The strains of Dermatophilus congolensis grew on blood agar with washed sheep erythrocytes with marked total hemolysis. In testing for hemolytic interactions they gave a significant synergistic effect of a characteristic shape with Rhodococcus equi and Streptococcus agalactiae, whereas with Staphylococcus aureus producing beta hemolysin and with Staphylococcus aureus producing delta hemolysin a simultaneous synergistic as well as antagonistic effect were observed. First of all a conspicuous inhibition of in the beta hemolysin zone began and then the hemolytic effect of D. congolensis was enhanced. A similar double reaction was also observed with Listeria ivanovii. With delta hemolysin there was an inhibition of the hemolytic effect of D. congolensis and at the same time a synergistic effect could be observed. Also D. congolensis gave a weak synergistic effect with Micrococcus lylae and Listeria monocytogenes, and a further weak antagonistic effect with alpha hemolysin of Staphylococcus aureus, Staphylococcus hyicus, Staphylococcus chromogenes and Micrococcus luteus. No interaction of D. congolensis was established with Corynebacterium pseudotuberculosis.

Actinomycetales↗
PubMed1992

Experimental dermatophilosis.

The histopathologic features of an experimental dermatophilosis of rabbit skin were described. The strain of Dermatophilus congolensis used for the experimental infection was obtained from the unique isolation and cultivation of this actinomycete from the ulcerous leg lesion of one male patient. Further strains in experiment came from the collections of type cultures. The experimental infection was characterized as an exudative and crustal dermatitis with acanthosis and subcorneal abscesses. Branching hyphae and clusters of coccoid bodies were found mostly in the parakeratotic layer and infrequently in the abscesses. Both the coccoid bodies and the hyphae were Gram-positive. The hyphae were acid-fast but the coccoid bodies were non-acid-fast. The fine structure of hyphae and coccoid bodies, namely of those with flagella, was also described by means of a transmission and scanning electron microscope.

Actinomycetales↗
PubMed1992

[The first isolation of Dermatophilus congolensis van Saceghem 1913 in Czechoslovakia].

The authors present a report on the first detection of the strain Dermatophilus congolensis in Czechoslovakia. The strain was isolated from ulcerations on the dorsal part of the foot of a 47-year-old patient who previously worked for several years in Libya. Based on examinations of smears from cultures of an isolated strain and four strains from a collection, from experimental dermatofilosis of a rabbit the authors describe the micromorphology of strains of D. congolensis under a light and electron microscope (transmission an and raster microscope). They describe the colonial morphology, haemolytic properties and in particular detail the haemolytic interaction of strains of D. congolensis with Streptococcus agalactiae, Rhodococcus equi and with strains of S. aureus (monoproducers of beta-haemolysin and delta-haemolysin resp.). They assessed the sensitivity of strains of D. congolensis to some staphylococcal bacteriocin-like substances.

Actinomycetales↗
PubMed1991

[Occurrence of staphylococcal species in clinically healthy domestic animals].

The incidence of staphylococcus species in healthy animals was investigated in young and adult individuals of cattle, in pigs and in domestic fowl, using the method of selective isolation of strains. A total of 6066 samples was examined; 4567 strains were revealed and they included all known species, except Staphylococcus caseolyticus, S. saccharolyticus, S. schleiferi and S. lugdunensis. 3.8% of strains failed to be identified with any species. The test samples were taken from slaughtered animals, only in calves intravital smears of tonsils were examined. The species most frequently isolated from the tonsil tissue in adult cattle were as follows: S. aureus (19.9%), S. saprophyticus (12.4%), S. hyicus (8.8%) and S. hominis (8.6%). The following species were isolated from the lung tissue: S. saprophyticus (28.8%), S. cohnii (10.6%) and S. epidermidis (10.2%); from the mammary gland parenchyma these were the species S. saprophyticus (17.4%), S. xylosus (13.1%) and S. epidermidis (10%). In the tonsil tissue of pigs the percent proportions of S. aureus and S. hyicus were 44.5% and 31.8%, respectively; the most frequent species detected from the lungs were S. aureus (20.6%), S. saprophyticus (12.3%), S. hyicus (12.1%) and S. epidermidis (11.5%). In domestic fowl the most frequently occurring species were S. epidermidis (23.7%), S. gallinarum (16.5%) and S. aureus (15.4%). In calves the incidence of S. xylosus (37%), S. saprophyticus (19.2%) and S. cohnii (15.2%) was found to be highest. The indicence of the other staphylococcus species in all test animals can be expressed by low percentages.

Animals↗
PubMed1990

[Slime production, hemolysis and proteolysis in coagulase-negative staphylococci isolated in hemoculture from humans].

Of 162 strain of coagulase negative staphylococci isolated from haemocultures most frequently the following were identified: S. epidermidis (56.8%), S. haemolyticus (17.3%) and S. hominis (14.2%). By means of the STAPHYtest first 138 strains were assessed (85.2%). Mucus formation was proved in 26 strains (16.0%) of six different species. Haemolytic activity was present in 131 strains (80.9%) in seven species, significantly more frequently in S. haemolyticus. Proteolytic activity was displayed by 118 strains (72.8%) of all nine identified species, significantly more often in S. epidermidis. Mucus and protease formation, haemolysin and protease formation as well as simultaneous formation of all three factors was observed most frequently in S. epidermidis. Strains of S. epidermidis thus have more frequently signs considered virulence factors than strains of the other species of coagulase negative staphylococci.

Coagulase↗