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At least 19 recordsLinked to original sources
PubMed1983

Morphological, biochemical, antigenic, and cytochemical relationships among Haemophilus somnus, Haemophilus agni, Haemophilus haemoglobinophilus, Histophilus ovis, and Actinobacillus seminis.

Morphology, biochemical reactions, pigmentation, antigens, and cell envelope proteins were examined in 12 strains of Haemophilus somnus, Haemophilus agni, Histophilus ovis, and Actinobacillus seminis. All of the strains except A. seminis are related and are considered as a single Haemophilus-Histophilus (HH) group. In immunodiffusion tests, HH group bacteria had at least two antigens common to all members of the group, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that they have similar cell envelope protein profiles. A quantitatively variable yellow pigment with absorption maxima of 430 to 435 nm was present in strains of H. somnus and H. agni. The HH group did not produce catalase and grew only in air containing 10% CO2. Of 10 HH group bacteria, 9 required thiamine monophosphate for growth. A. seminis was distinguished from the HH group by its lack of yellow pigment, production of catalase, growth in air, lack of a thiamine monophosphate requirement, and different cell envelope protein profile. In gel immunodiffusion tests, A. seminis antigens produced two lines of partial identity with the HH group when antiserum against H. somnus was used. Reference strains of Haemophilus influenzae, Actinobacillus lignieresii, and Haemophilus haemoglobinophilus were compared with the test strains. In immunodiffusion tests, a single antigen was found to be common to H. haemoglobinophilus, A. seminis, and the HH group. No similarities between any of the test strains and H. influenzae or A. lignieresii were noted. The close relationship of H. somnus, H. agni, and Histophilus ovis suggests that these unofficially named bacteria may belong to a single taxon.

Actinobacillus↗
PubMed1985

Characterization of Haemophilus spp. isolated from healthy swine and evaluation of cross-reactivity of complement-fixing antibodies to Haemophilus pleuropneumoniae and Haemophilus taxon "minor group".

Of 30 sows from a herd believed to be free of Haemophilus pleuropneumoniae infection, 2 had complement-fixing antibodies to H. pleuropneumoniae serotype 5. Necropsy and microbiological examination of the two sows revealed no evidence of H. pleuropneumoniae infection; however, Haemophilus taxon "minor group" and a urease-negative, indole-positive Haemophilus sp. were isolated from numerous respiratory tract sites in both sows. Isolation of these Haemophilus spp. was facilitated by serially diluting specimens in two broth media. Pigs from a closed, respiratory disease-free herd were inoculated with four strains of Haemophilus taxon "minor group" to determine whether the organism induces antibodies which cross-react with H. pleuropneumoniae in the complement fixation test. Antigenic heterogeneity among the taxon "minor group" strains was apparent; however, antibodies cross-reacting between these strains and H. pleuropneumoniae serotypes 1 through 5 and 7 were not detected.

Animals↗
PubMed1990

Multivariate analyses of carbohydrate data from lipopolysaccharides of Actinobacillus (Haemophilus) actinomycetemcomitans, Haemophilus aphrophilus, and Haemophilus paraphrophilus.

The taxonomic distinction between Actinobacillus (Haemophilus) actinomycetemcomitans and Haemophilus aphrophilus and the taxonomic distinction between H. aphrophilus and Haemophilus paraphrophilus have been questioned. This study was done to determine whether multivariate statistical analyses of carbohydrate data from lipopolysaccharides could be used to distinguish between these closely related species. Lipopolysaccharides were extracted with phenol-water and purified. Carbohydrates were assessed by using gas chromatography and gas chromatography-mass spectrometry after methanolysis and derivatization with trifluoroacetic acid anhydride. The lipopolysaccharides from all of the species contained rhamnose, fucose, galactose, glucose, L-glycero-D-mannoheptose, and glucosamine plus galactosamine, but in varying amounts. A. actinomycetemcomitans and H. paraphrophilus also contained D-glycero-D-mannoheptose, while H. aphrophilus did not. Sample- and variable-oriented principal-component analyses of the carbohydrate data clearly distinguished among A. actinomycetemcomitans, H. aphrophilus, and H. paraphrophilus. Soft independent modelling of class analogy showed that no sample in the A. actinomycetemcomitans class fell within the 95% confidence limits of the H. aphrophilus class. H. paraphrophilus fell outside both classes.

Actinobacillus↗
PubMed1992

Broth microdilution testing of Haemophilus influenzae with haemophilus test medium versus lysed horse blood broth. Canadian Haemophilus Study Group.

Broth microdilution testing of 702 community-acquired isolates of Haemophilus influenzae from across Canada was performed with both Mueller-Hinton broth supplemented with 3% lysed horse blood broth (LHB) (BBL Microbiology Systems, Cockeysville, Md.) and haemophilus test medium (HTM). The prevalence of beta-lactamase production was found to be 26% with no regional variation. MICs determined with LHB tended to be higher than those with HTM, but interpretive errors due to these differences were observed only rarely with trimethoprim-sulfamethoxazole (n = 5), cefaclor (n = 8), and cefamandole (n = 3). The interobserver variability in MIC determinations was found to be greater when LHB was used than when HTM was used. There was no difference in intraobserver variability between the two medium formulations. beta-Lactamase-positive isolates developed false resistance to amoxicillin-clavulanate 2 weeks after microdilution panels of both types of medium were stored at -20 degrees C but not when panels were stored at -70 degrees C. In conclusion, this study supports the use of HTM rather than LHB for sensitivity testing of H. influenzae because of its lower rate of interobserver variability and its ability to support the growth of these organisms, which is comparable to that of LHB.

Amoxicillin↗
PubMed1990

Differentiation between Actinobacillus (Haemophilus) actinomycetemcomitans, Haemophilus aphrophilus and Haemophilus paraphrophilus by multilocus enzyme electrophoresis.

Genetic relationships among isolates assigned to Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus and H. paraphrophilus were determined by analysis of electrophoretically demonstrable allelic variation in 14 structural genes encoding metabolic enzymes. Among the 51 isolates analysed there were 25 electrophoretic types (ETs), among which mean genetic diversity per locus was 0.753. Cluster analysis of ETs demonstrated one well-defined group of 11 ETs representing solely the genotypes of all 17 isolates assigned to A. actinomycetemcomitans. The remaining 14 ETs represented the genotypes of the 34 isolates of H. aphrophilus and H. paraphrophilus. With the exception of ATCC 13252, all strains of H. aphrophilus were closely related, whereas strains assigned to H. paraphrophilus included distantly related lineages, some of which were similar to those of H. aphrophilus and should be assigned to this species. Thus, the study showed that there is no significant overall genetic similarity between A. actinomycetemcomitans and the two Haemophilus spp.

Actinobacillus↗
PubMed1977

[Contribution to the experimental haemophilus infection (haemophilus parahemolyticus, haemophilus parasuis) in specific pathogen-free piglets. 1. microbiology, experimental arrangement, results].

Experimental infections were applied to specific pathogen free (SPF) piglets and store pigs, using five haemophilus (H.) parahaemolyticus and two H.-parasuis strains. Different germs counts and modes of application were chosen for each of the animals involved (intratracheal, intranasal, and subcutaneous routes). Clinical and pathologico-anatomic changes typical of haemorrhagic-necrotising pleuropneumonia were obtained from all germ counts and methods of application. Only one of the test animals could be successfully infected to exhibit manifestations of pneumonia or serositis when H. parasuis was used. The high pathogenicity of H. parahaemolyticus, as recorded from the above experiments, was in agreement with the growing incidence of that haemophilosis recordable for some time from pig stock.

Animals↗
PubMed1975

Methylase activities from Haemophilus influenzae that protect Haemophilus parainfluenzae transforming deoxyribonucleic acid from inactivation by Haemophilus influenzae endonuclease R.

Specific methylases that have the properties of deoxyribonucleic acid (DNA) modification enzymes have been isolated from Haemophilus influenzae strain Rd. Two activities ((Methylase IIa and methylase III) were found to protect transforming DNA of H. parainfluenzae from the action of H. influenzae restriction enzymes. To determine the specificty of the protection, a procedure based on biological activity was developed for the separation and purification of the restriction endonucleases from H. influenzae strain Rd. Two endonuclease R activities presumably corresponding to Hind II and Hind III (P. H. Roy and H. O. Smith, 1973; H. O. Smith and K. W. Wilcox, 1970) were characterized by differences in their chromatographic properties, ability to attack T7 DNA, and inactivation of the transforming activity of different markers of H. parainfluenzae DNA. One endonuclease R enzyme (Hind II) attacked T7 DNA and was found to inactivate the dalacin resistance marker (smaller than 0.01% activity remaining) with only a slight effect on the streptomycin resistance marker (83% activity remaining). Methylase IIa treatment protected 40% of the dalacin resistance marker of H. parainfluenzae DNA from inactivation by Hind II. The other restriction activity (Hind III) was inert towards T7 DNA and inactivated the streptomycin resistance marker of H. parainfluenzae DNA (smaller than 0.01% activity remaining) without any effect on the dalacin resistance marker. The methylation of H. parainfluenzae DNA accomplished by methylase III protected 60% of the transforming activity of the streptomycin resistance marker of H. parainfluenzae DNA from the action of Hind III.

DNA (Cytosine-5-)-Methyltransferases↗
PubMedDate not supplied

Invasive infections caused by Haemophilus species other than Haemophilus influenzae.

In a retrospective study covering a 13-year period and a population of 817,900 inhabitants, 13 cases of invasive infection caused by Haemophilus species other than Haemophilus influenzae were found. Ten of the infectious episodes were caused by Haemophilus parainfluenzae and three by Haemophilus aphrophilus. The clinical manifestations comprised endocarditis, meningitis, pleuropneumonia, epiglottitis and septicaemia from an unknown focus. These 13 infectious episodes caused by uncommon Haemophilus species constituted less than 3% of the total number (473) of invasive Haemophilus infections registered during the same period of time. Invasive H. influenzae infections were more common in all age groups than infections caused by other Haemophilus species. In contrast to H. influenzae infections, which predominate in childhood, invasive infections due to uncommon Haemophilus species had no predilection for any age group.

Adult↗
PubMed1989

Distribution of Haemophilus influenzae and Haemophilus parainfluenzae biotypes isolated from the human genitourinary tract.

A total of 3,598 genital specimens from men and women was cultured for Haemophilus spp. using a simple selective culture method. Two hundred and thirty three samples (6.5%) were positive for Haemophilus spp., 216 Haemophilus parainfluenzae and 28 Haemophilus influenzae strains being isolated. Biotyping demonstrated that Haemophilus parainfluenzae biotype II was dominant at all sites, especially the male urethra, comprising 59% of all Haemophilus strains isolated. On the other hand, Haemophilus influenzae biotype IV was isolated from only six patients and thus was not a major genital biotype. The respective proportions of the two Haemophilus spp. recovered from various mucosal sites led to the supposition that the genitourinary colonization originated either from the upper respiratory tract or the gastrointestinal tract.

Adolescent↗
PubMed1990

Evaluation of a selective medium for the isolation and differentiation of Haemophilus influenzae and Haemophilus parainfluenzae from the respiratory tract of chronic bronchitics.

Respiratory tract specimens from chronic bronchitic patients were cultured for Haemophilus species on conventional chocolate agar and a modified sucrose medium in order to determine the accuracy of the new medium in differentiating Haemophilus influenzae from Haemophilus parainfluenzae strains. Haemophilus influenzae biotypes II and III and Haemophilus parainfluenzae biotypes I and II were found to be the predominant strains isolated from the respiratory tract. The modified sucrose medium was found to be a rapid and reliable means of differentiating Haemophilus influenzae from Haemophilus parainfluenzae by sucrose fermentation, on initial isolation.

Bronchitis↗
PubMed1983

Siblings of patients with Haemophilus meningitis have impaired anticapsular antibody responses to Haemophilus vaccine.

Siblings of patients with type b Haemophilus influenzae meningitis are at increased risk of developing Haemophilus disease. We immunized 26 healthy siblings and 25 control subjects using a vaccine containing the type b polysaccharide capsule (10 micrograms PRP) and pertussis vaccine (4 opacity units) (Lederle Laboratories) to determine whether siblings of patients with Haemophilus meningitis had an impaired antibody response to PRP. Using two intramuscular injections one month apart, we found that the siblings had a lower response to PRP. One month after the second injection, 12 of 24 of the siblings had serum concentrations of anticapsular (PRP) antibody thought to be sufficient to confer protection against Haemophilus disease (greater than or equal to 300 ng/ml), compared with 19 of 24 of the control children tested (50% vs 79%, P = 0.035 by chi-square analysis). In comparison with the normal controls, the siblings produced significantly less IgG anti-PRP antibody but similar amounts of IgM. The impaired responsiveness to PRP was most evident among the 16 children born after their sibling had meningitis and who were not known to have been exposed to type b Haemophilus infection previously. These data indicate that siblings of some patients with type b Haemophilus meningitis have reduced ability to form IgG anti-PRP antibody, which may be associated with increased susceptibility to Haemophilus disease.

Antibodies, Bacterial↗
PubMed1994

Revised disk diffusion interpretive criteria for cefaclor, loracarbef, cefprozil and cefixime when testing Haemophilus influenzae on haemophilus test medium.

The aim of the current five-center collaborative study was to reassess the interpretive criteria for cefaclor, loracarbef, cefprozil and cefixime previously adopted or proposed by the National Committee for Clinical Laboratory Standards (NCCLS) for disk diffusion susceptibility tests with Haemophilus influenzae on Haemophilus Test Medium (HTM) agar. MICs and zones of inhibition were determined using NCCLS methods, HTM and two collections of strains of Haemophilus influenzae. One group of strains consisted of 118 stock organisms taken largely from various recent U.S. antibiotic resistance surveillance studies. The emphasis in this selected group of organisms was on strains that were beta-lactamase negative but ampicillin resistant (BLNAR) by some other mechanism. The second collection of test organisms consisted of 50 recent clinical isolates of Haemophilus influenzae obtained from each of the five participating study centers. This group was considered representative of the type of Haemophilus influenzae currently recovered from clinical sources in the USA. Frequency distribution assessment and error-rate bounded analysis of scattergram comparisons of MICs and zone sizes were used to develop the following zone diameters interpretive for disk diffusion susceptibility tests with Haemophilus influenzae on HTM agar: cefaclor, > or = 20 mm (susceptible, S) and < or = 16 mm (resistant, R); loracarbef, > or = 19 mm (S) and < or = 15 mm (R); and cefprozil, > 18 mm (S) and < 14 mm (R). The respective MIC correlates for all three antimicrobial agents were < or = 8 micrograms/ml (S) and 32 micrograms/ml (R).(ABSTRACT TRUNCATED AT 250 WORDS)

Cefaclor↗
PubMed1990

Disk diffusion susceptibility testing of Haemophilus influenzae using haemophilus test medium.

A three-center collaborative study was performed with the aim of determining the reproducibility of disk diffusion and broth microdilution susceptibility tests of Haemophilus influenzae with 19 different antimicrobial agents using a newly described medium, Haemophilus Test Medium. The results of both methods were found to be highly reproducible. Using Haemophilus Test Medium, inhibitory zone diameters and MICs were then determined for 150 test strains of Haemophilus influenzae, selected with an emphasis on known mechanisms of resistance. Regression analysis of zone diameter-MIC comparisons was used to define zone diameter interpretive criteria and MIC correlates for Haemophilus Test Medium disk diffusion tests performed with Haemophilus spp. for the following antimicrobial agents: ampicillin, amoxicillin/clavulanate, ampicillin/sulbactam, cefaclor, cefuroxime, cefamandole, ceftriaxone, cefotaxime, ceftizoxime, ceftazidime, cefixime, trimethoprim/sulfamethoxazole, rifampin, chloramphenicol, tetracycline, imipenem, aztreonam and ciprofloxacin.

Anti-Bacterial Agents↗
PubMed1992

Isolation and characterization of a newly identified Haemophilus species from cats: "Haemophilus felis".

A gram-negative coccobacillus was isolated from the lower respiratory tract of a cat with chronic obstructive pulmonary disease. The isolate required CO2 and V factor for growth and was initially identified as Haemophilus paraphrophilus on the basis of its nutritional requirements, colony morphology, and some biochemical tests. Because of the host specificity of Haemophilus species and discrepancies in catalase, oxidase, and hemolytic activities, additional testing was done. Extensive biochemical testing, G+C content, and DNA reassociation studies indicated that the organism was distinct from other Haemophilus species. Therefore, the organism was identified as a previously unrecognized Haemophilus species and was tentatively named "Haemophilus felis." Bacteria identical to the original isolate were isolated from the nasopharynxes of 6 of 28 apparently normal cats, indicating that H. felis or H. felis-like organisms may be common members of the feline upper respiratory tract flora.

Animals↗
PubMed1984

Response to immunization with Haemophilus influenzae type b polysaccharide-pertussis vaccine and risk of Haemophilus meningitis in children with the Km(1) immunoglobulin allotype.

In experimental animals, immune responses to certain antigens are regulated by immunoglobulin allotype-linked genes. In an effort to detect such genes in humans, we examined the antibody responses of 74 healthy children with different Km(1) or Gm(23) allotypes to a Haemophilus influenzae type b vaccine (type b polysaccharide capsule-pertussis vaccine). The anticapsular antibody responses of black or white children with the Km(1) allotype were 4.6- to 9.5-fold higher than those of children who lacked this determinant (P less than 0.004). No significant differences were found in antibody response with respect to the Gm(23) allotype. The frequencies of Km(1) and Gm(23) also were examined in 170 patients with Haemophilus meningitis, 71 patients with epiglottitis, and 173 control children. Km(1) was detected less frequently in black patients with meningitis (38%) than in those with epiglottitis (81%, P less than 0.002) or in controls (66%, P less than 0.0007). The relative risk of meningitis thus was 3.2-fold lower among black children with the Km(1) allotype than in those who lacked this allotype (odds ratio = 0.3, 95% confidence interval 0.2 to 0.6). However, the risk of meningitis was not decreased in white children with the Km(1) allotype (odds ratio = 1.0). There were no significant differences in the frequency of Gm(23) among the patient groups and controls. The Km(1) allotype but not the Gm(23) thus defines a subpopulation of children of both races who are high responders to this vaccine, and black children but not white children with the Km(1) allotype are at decreased risk of developing Haemophilus meningitis. These data indicate that in blacks, genes associated with Km(1) may affect immune response to a prototype type b Haemophilus vaccine, and perhaps interact with another factor related to race to affect susceptibility to Haemophilus meningitis.

Antibodies, Bacterial↗
PubMed1988

[Neonatal infections caused by Haemophilus influenzae and Haemophilus parainfluenzae].

Haemophilus influenzae is a frequent causal agent of serious infections in infants. Mostly these infections occur at the age of 3 months to 3 years. Reports about infections in the neonatal period were rare in the past and most of them were single cases. In the last years an increase of neonatal infections due to Haemophilus influenzae had been reported. In the period from June 1980 to January 1986 we saw 5 newborns with severe infections due to Haemophilus influenzae and one neonate infected by Haemophilus parainfluenzae. By discussion of our cases and by review of the literature we want to show important aspects of pathogenesis, clinical symptoms, diagnostics and therapy of neonatal infections due to bacteria of the genus Haemophilus.

Haemophilus Infections↗
PubMed1990

Antimicrobial susceptibility testing of less commonly isolated Haemophilus species using Haemophilus test medium.

Haemophilus test medium (HTM) was developed recently for dilution and disk diffusion antimicrobial agent susceptibility testing of Haemophilus influenzae. The application of HTM to the testing of other, less frequently encountered Haemophilus species recovered from humans was evaluated in this study by using commercially prepared HTM (BBL Microbiology Systems, Cockeysville, Md.) in broth microdilution and agar disk diffusion susceptibility tests with 18 antimicrobial agents. A total of 93.3% of 90 isolates belonging to six Haemophilus species provided acceptable growth in HTM agar disk diffusion tests, while only 63.3% (57 of 90) provided acceptable growth in the broth microdilution tests. However, HTM agar dilution testing provided an alternative method for those strains (primarily H. haemolyticus) which failed to grow adequately in broth. Based on the latest National Committee for Clinical Laboratory Standards guidelines (standard M2-T4) for interpretation of HTM disk tests of H. influenzae, the overall very major, major, and minor errors for all 18 drugs and six species tested were 0.2, 0.7, and 3.4%, respectively. Thus, the use of HTM in agar or broth susceptibility tests can be recommended for testing the less commonly encountered Haemophilus species by using the same test conditions and interpretive guidelines developed for H. influenzae.

Culture Media↗