Haemophili and related bacteria in the human oral cavity

Are certain oral pathogens part of normal oral flora in denture-wearing edentulous subjects?

A complete loss of teeth may eliminate some pathogenic bacteria for lack of a suitable habitat for colonization. The occurrence of Actinobacillus actinomycetemcomitans, black-pigmented Bacteroides, mutans streptococci, lactobacilli and yeasts was investigated in 51 edentulous subjects with complete denture(s); mean age 74 years (range 44-92 years). None of the subjects had received antibiotics during the preceding 6 months. Four swab samples per subject were taken from the fitting surface of the upper denture, from the palate, buccal mucosae and dorsum of the tongue. At least 0.5 ml of stimulated saliva was collected into a sterile tube. The samples were cultivated aerobically and anaerobically using nonselective and selective media. A. actinomycetemcomitans was not found in any of the samples. Black-pigmented Bacteroides were found in 49 (96%) and yeasts in 25 (49%) of the subjects. Of the 49 saliva samples, 41 (84%) yielded mutans streptococci and 45 (92%) lactobacilli. In contrast to black-pigmented Bacteroides, mutans streptococci and lactobacilli, A. actinomycetemcomitans may not belong to the normal oral flora of edentulous subjects wearing dentures.

Intrafamilial transmission of Actinobacillus actinomycetemcomitans

Cross-sectional studies have shown that Actinobacillus actinomycetemcomitans is a frequent member of the oral flora in children with primary teeth. The purpose of the present study was to obtain information of the transmission of A. actinomycetemcomitans. Three types of families were studied for the prevalence and serotype distribution of A. actinomycetemcomitans. First, families whose periodontally healthy child member harbored A. actinomycetemcomitans; second, families of periodontally healthy children who did not harbor A. actinomycetemcomitans; third, families whose adult member harbored A. actinomycetemcomitans and had been referred to treatment for severe periodontitis. As a whole the study included 23 families. All the family members were invited for the examination. The final study population consisted of 38 children and 32 adults. The results showed that when a child was positive for A. actinomycetemcomitans, either the mother or the father was also positive with one exception, whereas when the adult member harbored A. actinomycetemcomitans, the children were infected in only 2 of the 9 families. Using immunodiffusion technique it was found that the child always harbored the same serotype of A. actinomycetemcomitans as the parent. In conclusion, the results suggest the intrafamilial transmittance of A. actinomycetemcomitans.

Salivary defense mechanisms in juvenile periodontitis

The local, saliva-associated defense mechanisms of 28 juvenile periodontitis (JP) patients and their age- and sex-matched controls were studied. Lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, and thiocyanate concentrations were determined from both whole saliva and parotid saliva. The total concentrations of salivary IgA, IgG, and IgM were assayed. The periodontal condition and the salivary flow rates were registered. Among the JP patients, a significantly elevated concentration of IgG was found in parotid saliva but not in whole saliva. Salivary peroxidase activities were significantly low both in the whole and in the parotid saliva samples of the JP patients, and leukocyte-derived myeloperoxidase was present in significantly low amounts in whole saliva of these patients. Because both glandular (salivary peroxidase) and polymorphonuclear-cell-derived (myeloperoxidase) enzyme activities were low among the JP patients, suppressed peroxidase-mediated host defense mechanisms could be characteristic of JP.

Microbial patterns in pooled subgingival plaque samples from young adults with advanced marginal periodontitis

Different bacterial profiles of subgingival plaque have been described for different clinical categories of marginal periodontitis. In the present investigation the subgingival microflora was studied in young adults with advanced marginal periodontitis. From 12 patients pooled subgingival plaque samples from 5 advanced stages of diseased sites were examined by direct differential phase-contrast microscopy and by cultivation on enriched and selective media. The proportions of the following genera and species were calculated: black-pigmented Bacteroides sp., B. gingivalis, Fusobacterium nucleatum, Veillonella sp., Actinobacillus actinomycetemcomitans, Capnocytophaga sp., Eikenella corrodens, Campylobacter sp., and Candida sp. Spirochete identification was carried out ultrastructurally. Calculated percent minimum similarity levels between the individuals revealed that each patient harbored its characteristic cultivable subgingival microflora different from the other individuals. The spirochetes seemed to constitute the subgingival bacterial group with the smallest variation as certain morphotypes were dominating in almost all individuals.

Plasmids in Actinobacillus actinomycetemcomitans strains isolated from periodontal lesions of patients with rapidly destructive periodontitis

Several strains of Actinobacillus actinomycetemcomitans newly isolated from periodontal lesions of patients with rapidly destructive periodontitis were all shown to possess identical plasmid profiles consisting of 4 plasmids. The largest plasmid, 20 MegaDalton (MDa), was also found in reference strains. Two different methods were used for isolation of the plasmids; the large 20 MDa plasmid (pHRP1) was found using the Kado and Liu method only. The 3 small plasmids of 7.0, 5.2 and 4.0 MDa (pHRP2, pHRP3, pHRP4), respectively, were seen using the Birnboim and Doly method. These plasmids are so far to be regarded as cryptic; no phenotypical characters have been linked to their presence. The large 20 MDa plasmid was found in all strains examined, and may be a genotypical marker for the A. actinomycetemcomitans species.

Actinobacillus actinomycetemcomitans contamination of toothbrushes from patients harbouring the organism

The main ecological niche of Actinobacillus actinomycetemcomitans (A.a.) seems to be the periodontal pocket, but it can also be isolated from supragingival plaque, buccal and tongue mucosa, or saliva. We examined toothbrushes from 21 patients, all identified as harbouring moderate to large numbers of A.a. in subgingival plaque, for contamination with this organism. 29% of the toothbrushes presented by our patients yielded detectable numbers of A.a. Immediately after toothbrushing this figure rose to 62%, but dropped to 50% after 1 h. Numbers of isolated A.a. on toothbrushes were weakly correlated with the degree of periodontal destruction, and significantly more numbers of A.a. on toothbrushes could be detected if the organism was found on mucous membranes or in saliva. There was no association with gingival inflammation, supragingival plaque nor mean numbers of isolated subgingival A.a.

The role of Actinobacillus actinomycetemcomitans in periodontal disease

The different forms of periodontitis are all associated with a distinct bacterial flora. However, a clear relationship is described between localized juvenile periodontitis (LJP) and Actinobacillus actinomycetemcomitans. Eleven LJP patients all harboured A. actinomycetemcomitans. The arrest of LJP is often impossible, due to the inability to eliminate A. actinomycetemcomitans. Therefore, antibiotic treatment was introduced in combination with the initial treatment. We studied the effect of periodontal treatment on the microflora and clinical status of periodontal disease patients using different therapies. Group 3 attained the best results (initial treatment and a combination metronidazole and amoxicillin), the group to eliminate A. actinomycetemcomitans effectively.

Intra-oral colonization of macaque monkeys by Actinobacillus actinomycetemcomitans

Actinobacillus actinomycetemcomitans was acquired by captive Macaca fascicularis 3 to 6 months after birth, and all monkeys aged over 6 months harbored detectable levels. This microorganism was most frequently isolated from the gingival plaque of the incisor (and other) teeth compared with other oral sites. Strains were leukotoxic by bioassay and Western blot analysis. Antibodies in macaque serum contained neutralized the leukotoxin of a human A. actinomycetemcomitans strain. High titres of maternal neutralizing anti-leukotoxin antibodies were detected in neonates; the titre then fell rapidly so that by 6 months the antibody titer was zero. Antileukotoxin antibody production was detected after 6 months of age, rapidly reaching a high level within 2 years after birth. The presence of leukotoxic strains of A. actinomycetemcomitans in the gingival region did not appear to be correlated with an increase in susceptibility to periodontal disease.

Incidence of selected ureolytic bacteria in human dental plaque from sites with differing salivary access

Saliva is the main source of urea in the human mouth and may be responsible for the predilection of ureolytic bacteria for certain tooth sites. As a test of this hypothesis, the ureolytic bacteria, Haemophilus parainfluenzae, Actinomyces naeslundii, Actinomyces viscosus and coagulase-negative oral staphylococci, were enumerated in supragingival plaque from various sites in each of 10 subjects. The sites sampled included the maxillary and mandibular incisors (chosen because the lower incisors are more exposed to the submandibular-sublingual secretion than the upper) and the maxillary and mandibular molars (the upper molars being closer to the source of parotid saliva). After dispersion of the plaque samples in saline, subsamples of each suspension were plated on appropriate selective media and other subsamples were taken for nitrogen analysis to measure the amount of plaque sampled. H. parainfluenzae that used urea was present in the largest numbers, A. viscosus was next and A. naeslundii and coagulase-negative staphylococci were least. The staphylococci and H. parainfluenzae were more numerous from mandibular than from maxillary incisors and from maxillary than mandibular molars, a pattern which suggests that salivary access favours their selection. The numbers of A. viscosus and A. naeslundii were not related to salivary access: A. viscosus was most numerous from the maxillary incisors, possibly because this site is normally the most acidic of the four studied and A. viscosus is strongly acidogenic and aciduric; the incidence of A. naeslundii had no relationship with site.(ABSTRACT TRUNCATED AT 250 WORDS)

Selected low-cohesion variants of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus lack distinct antigens recognized by human antibodies

Actinobacillus actinomycetemcomitans OMZ 346 A and Haemophilus aphrophilus OMZ 384 A, isolated on a synthetic selective and differentiating agar, show the highly cohesive and wall adherent growth in liquid medium which is typical for all primary oral isolates of these species. From each of them a low cohesion variant, OMZ 346 F and OMZ 384 F, respectively, was obtained by selection for cells growing in suspension. Screening of Western blots of these four strains with several human sera revealed the loss of a 4000 Mr antigen in both F strains. Human antibodies bound to the 4000 Mr band material on preparative Western blots of the A strains were eluted with 4 M magnesium chloride. These antibodies showed no cross-reaction between the 4000 Mr material of the two closely related species.

The role of antibody, complement and neutrophils in host defense against Actinobacillus actinomycetemcomitans

A. actinomycetemcomitans is a facultative Gram-negative coccobacillus which has been implicated in the etiology and pathogenesis of localized juvenile periodontitis and has also been recognized for its potential to cause serious extraoral infections, particularly endocarditis. The polymorphonuclear neutrophil has been suggested to play a key role in host resistance to periodontopathic organisms, as indicated by the association between defective production or function of these phagocytic cells and severe periodontal disease. This association has engendered interest in the study of the interaction between neutrophils and A. actinomycetemcomitans, as well as the role of immunoglobulin and complement in facilitating this interaction. The objective of this review is to summarize current knowledge of the nature and consequences of the interaction between A. actinomycetemcomitans and the host defense triad consisting of neutrophils, complement and immunoglobulin.

Effects of immunization with B. macacae on induced periodontitis--preliminary findings

This preliminary study examined the effects of immunization with Bacteroides macacae, the monkey equivalent of the human species of B. gingivalis on ligature-induced periodontitis. During a 12 week immunization period, 8 out of the 12 Macacae fasicularis monkeys were immunized weekly with B. macacae washed cells and 4 were sham-immunized with saline. At the same time, all were scaled and pumiced weekly to establish gingival health. Following this period, the mandibular first molars were ligated in 8 out of the 12 monkeys to induce periodontitis. The immunized, ligated experimental group, the ligated, sham-immunized control group, and the immunized, non-ligated control group were then followed for a 6 months ligation period while plaque was allowed to accumulate. Gingival indices, attachment levels, pocket depths, plaque indices, radiographs, serum and crevicular fluid antibodies and subgingival bacteria were assessed. Immunization led to elevated antibody levels to B. macacae while ligation increased plaque, gingival inflammation, and bone loss. Following the 6 month ligation period, B. macacae comprised 1.7% of the cultivable flora in the immunized, non-ligated monkeys, 2.1% in the immunized, ligated monkeys, and 5.6% in the sham-immunized, ligated monkeys. Similar differences between the immunized, ligated and and the sham-immunized, ligated groups were not seen for B. intermedius, nor B. melaninogenicus. These results suggest a heightened humoral response to B. gingivalis reduces subgingival re-colonization by this organism and modulates the course of ligature-induced periodontitis.

Detection and distribution of Actinobacillus actinomycetemcomitans in the primary dentition

The occurrence of actinobacillus actinomycetemcomitans (A.a.) in plaque samples from the primary dentition was studied in 55 healthy Finnish children from four to seven years of age. A.a. was isolated in seven (13%) children, four boys and three girls. A further examination of the distribution and infection level of A.a. in the oral cavity of five of the A.a.-positive children revealed that A.a. was found in 26 of 45 plaque samples (7-10 samples from each child) and in all samples obtained from the dorsum of the tongue. The individual detection rates of A.a. were 3/7, 5/10, 6/10, 6/10 and 6/8 of the dental sites examined. A.a. occurred in 9/10 of the second primary molars, 8/10 of the first primary molars, 5/10 of the cuspids, 4/8 of the upper incisors and in none of the lower incisors examined. The proportions of A.a. within the dentition had a wide range. In 58% of the A.a.-positive samples, the proportions were less than 1%, and none exceeded 10% of the flora. Gingival bleeding after sampling with floss occurred more than twice as frequently in the A.a.-positive as in the A.a.-negative sites (16%/42%). The results indicate that A.a. was a rather frequent member of the oral flora in the children with primary teeth. The primary molars and the dorsum of the tongue seemed to be preferred sites for A.a. More than one site should be sampled to determine the infection level of A.a. within the dentition.

Microbiological and clinical effects of surgery plus doxycycline on juvenile periodontitis

It was previously determined that surgery plus the antibiotic doxycycline were effective in eliminating or suppressing Actinobacillus actinomycetemcomitans (Aa), an organism strongly associated with disease in localized juvenile periodontitis (LJP). Eight patients with LJP participated in this surgical study. Patients were reexamined three and 12 months following therapy. The results of this study strongly suggest that surgery plus doxycycline effectively eliminate Aa from periodontal pockets. This elimination results in clinical improvement and attachment gain at three and 12 months following surgery. Further destruction was seen in individuals who continued to harbor high levels of Aa.

Arthritis caused by Haemophilus paraphrophilus and isolation of the organism by using an improved culture protocol

A case of bacterial arthritis caused by Haemophilus paraphrophilus is presented. This is the first reported case of arthritis caused by this organism. Culturing joint fluid in blood culture bottles provides for bacteria that are slow growing or present in small numbers.

Improved selective culture media for Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus

By modifying the previously described media tryptic soy-serum-bacitracin-vancomycin (TSBV) agar and tryptic soy-serum-bacitracin-vancomycin-fluoride (TSBVF) agar, two improved selective culture media were developed for isolation and enumeration of Actinobacillus actinomycetemcomitans (A medium) and Haemophilus aphrophilus (H medium) in oral specimens. Both media were supplemented with fusidic acid and spiramycin, and carbenicillin was also added to A medium. The growth yields of pure cultures of A. actinomycetemcomitans on A medium and of H. aphrophilus on H medium were comparable with those on the reference media. Compared with blood agar, the selective media inhibited these species about 10-fold or less. In addition, A and H media suppressed the growth of pure cultures of Capnocytophaga spp. and Neisseria spp., commonly found as contaminants on TSBV and TSBVF, 10(5) times or more compared with that on blood agar. In samples from diseased periodontal pockets, the recoveries of A. actinomycetemcomitans on A medium and H. aphrophilus on H medium equaled those on TSBV and TSBVF, respectively. In about 50% of the cultures on the reference media, contaminating bacteria were detected at levels higher than 10(4) CFU/ml of sample. The corresponding value for both A and H media was about 2%.

Supraglottitis and Hemophilus parainfluenzae: pathogenic potential of the organism

Hemophilus parainfluenzae may be a normal inhabitant of the pharynx, but it can have pathogenic potential elsewhere in the body. It has been identified as a cause of bacteremia and meningitis. The case discussed here represents the first report of H parainfluenzae-induced supraglottitis in a child. In reviewing its pathogenic potential in the upper respiratory tract, it appears that its major effect could be the ability to transfer ampicillin resistance to ampicillin-susceptible Hemophilus influenzae.

Submandibular space abscess due to Actinobacillus actinomycetemcomitans

A submandibular space abscess is reported in which a pure culture of Actinobacillus actinomycetemcomitans was identified. The bacterium may often be overlooked as a pathogen due to its slow growth and its requirement for carbon dioxide for primary isolation. As A. actinomycetemcomitans is often resistant to commonly used antibiotics, proper management is based on careful utilization of microbiologic tests and clinical judgement. In this case prompt surgical drainage and appropriate antibiotic therapy resolved the abscess.

Is antibiotic therapy justified in the treatment of human chronic inflammatory periodontal disease?

New insight into the possible involvement of specific bacteria in the etiology of periodontal disease has stimulated interest in antibiotic therapy. However, current knowledge does not allow the designation of one or more pathogens in periodontal diseases. Some bacteria are considered suspected periodontal pathogens due to their predominance in the pocket and their potential pathogenicity, yet they all appear to be indigenous bacteria. For this reason, one can question the rationale for the use of antibiotics in the treatment of periodontal disease since the theoretical basis for their application seems small. Several reports of clinical trials in which antibiotics were administered as an adjunct to scaling and rootplaning in adult periodontitis conclude with encouraging statements concerning bacterial inhibition and the cure of inflammatory periodontal disease. However, the data are conflicting and mostly negative. Antibiotic treatment in combination with scaling and rootplaning in juvenile periodontitis and refractory adult periodontitis has shown some benefit, but the clinical trials were not sufficiently controlled to permit conclusions. So far, antibiotics have been applied as a last resort in order to supplement the non-specific approach of mechanical root debridement, but it can be doubted whether this approach offers any benefit in the long run.

Five cases of Haemophilus segnis appendicitis

The clinical, histological, and bacteriological findings in five cases of acute appendicitis caused by Haemophilus segnis are reported. This is the first documentation of appendicitis associated with this organism.

Chemotherapy in juvenile periodontitis

Juvenile periodontitis has been described as a separate entity among the human periodontal diseases. Several forms of the disease based on the number and types of involved teeth as well as the age of the patient have been reported. The present review deals with the "classical" localized juvenile periodontitis (LJP). The etiology of LJP has been explained according to 3 theories: (1) a genetic (hereditary) defect in the host defense mechanism; (2) a specific infection; (3) a combination of 1 and 2. In all 3 alternatives, bacterial infection is the direct cause of the breakdown of the tissues. This is supported by reports of success following therapy aimed at eliminating the microbial challenge. Arguments favoring the use of chemotherapeutic agents as an adjunct to mechanical debridement, or instead of it, as well as arguments against such use are discussed. The conclusion seems to be dependent on which of the 3 theories of etiology the arguments are related to. If antibiotics are to be used, the choice of drug would depend on the sensitivity of the suspected pathogen(s). At present tetracycline seems to be the one suggested by most authors, but routine use of antibiotics in the treatment of LJP does not seem necessary and is not recommended.

Relationships among isolates of oral haemophili as determined by DNA-DNA hybridization

In order to assess the relationships among strains of the genera Actinobacillus and Haemophilus, DNAs from 50 strains of these genera were isolated and purified. The guanine plus cytosine (G + C) content of DNAs from strains of Haemophilus segnis and Haemophilus parainfluenzae were determined by thermal denaturation. DNA-DNA homologies were measured using labelled probes from one strain representing Haemophilus segnis (strain ATCC 10977), and two strains representing Haemophilus parainfluenzae (strains ATCC 9796 and ATCC 7901). Strains isolated as H. segnis had a G + C content of 39.0 to 42.9% and were 49-92% homologous with the ATCC 10977 DNA probe. All of the strains freshly isolated as H. parainfluenzae were 70-81% homologous with the ATCC 9796 DNA probe and had a G + C content of 34.9 to 38.3%. Strain ATCC 7901 was 11% homologous with the ATCC 9796 DNA probe, had a G + C content of 42.4%, and was 65-78% homologous to DNA from strains identified as Haemophilus aphrophilus and Haemophilus paraphrophilus. From these results we conclude that strain ATCC 7901 is a mislabelled strain of H. paraphrophilus. The results of multiple DNA-DNA hybridizations indicated that separate species designations were appropriate for H. segnis, H. parainfluenzae, Actinobacillus actinomycetemcomitans ("Haemophilus actinomycetemcomitans"), and H. aphrophilus. H. aphrophilus and H. paraphrophilus were closely related organisms and did not fulfill the generally accepted criteria for designation as separate species.

Selective medium for the isolation of Haemophilus aphrophilus from the human periodontium and other oral sites and the low proportion of the organism in the oral flora

We developed a medium for the selective recovery of Haemophilus aphrophilus. The medium, designated TSBVF, was composed of 4% tryptic soy agar, 10% heat-inactivated horse serum, 75 micrograms of bacitracin per ml, 5 micrograms of vancomycin per ml, and 50 micrograms of sodium fluoride per ml. TSBVF yielded a threefold higher recovery of oral H. aphrophilus than did chocolate agar with 75 micrograms of bacitracin per ml, which is a medium routinely used to diagnose human Haemophilus infections. H. aphrophilus and the few contaminating organisms on TSBVF were readily distinguished on the basis of colony morphology. The H. aphrophilus isolates exhibited variable fermentation of raffinose and dextrin but otherwise were biochemically similar. In a clinical study, H. aphrophilus was frequently recovered from supragingival plaque and saliva and occasionally from buccal mucosa and the tonsils. It was also isolated from 29 of 56 subgingival sites in 11 of 14 subjects. Its proportion of the subgingival microflora averaged 0.13% for healthy periodontal sites, 0.05% for adult periodontitis lesions, and 0.03% for localized juvenile periodontitis lesions. We concluded that H. aphrophilus is an indigenous bacterium of the human oral cavity. It occurs in low proportions in subgingival plaque and plays no apparent role in advanced periodontal disease in humans.

The effect of treatment on Actinobacillus actinomycetemcomitans in localized juvenile periodontitis

Three treatment regimens including local tetracycline delivery, systemic doxycycline and surgery plus systemic doxycycline were investigated in a localized juvenile periodontitis (LJP) population. Of the investigated treatments only surgery plus systemic doxycycline for 14 days was effective in eliminating or suppressing Actinobacillus actinomycetemcomitans, an organism strongly associated with LJP lesions. While surgery plus antibiotics was the superior treatment, it appears that the possibility of reinfection or incomplete elimination of the organism exists. Careful long-term follow-up, including clinical and microbiological monitoring, is highly recommended in this periodontal population.

Serum and gingival fluid antibodies as adjuncts in the diagnosis of Actinobacillus actinomycetemcomitans-associated periodontal disease

Serum antibody titers to Actinobacillus actinomycetemcomitans were measured in 200 subjects by an enzyme-lined immunosorbent assay (ELISA) using whole microorganisms as antigen. Comparisons were made between titers found in periodontally normal subjects and titers in subjects with localized juvenile periodontitis (LJP), postlocalized juvenile periodontitis, generalized juvenile periodontitis or adult periodontitis. It was found that titers to all three serotypes of A. actinomycetemcomitans were elevated in LJP patients' sera, while serum antibody levels in other diseased groups were not significantly elevated to any of the serotypes. Patient sera were also examined for serum antibody to oral Haemophili previously shown to cross-react with A. actinomycetemcomitans. Similar antibody titers were found in both normal subjects and in patients with various forms of periodontal disease to Haemophilus aphrophilus, H. influenzae and H. parainfluenzae. The A. actinomycetemcomitans antibodies which were elevated in LJP patients could not be correlated with antibody titers to cross-reacting Haemophili, suggesting that these antibodies are A. actinomycetemcomitans-specific. Serum antibody responses in six of the LJP patients were assessed to autologous strains of A. actinomycetemcomitans. Each patient was found to be infected with only a single serotype of A. actinomycetemcomitans, and specific antibodies to the infecting serotype were found in the patients' sera. In families, the LJP patients had significantly elevated IgG, IgA and IgM serum antibody titers to A. actinomycetemcomitans, while the IgG and IgA antibody titers in periodontally normal siblings were at levels comparable to those found in normal subjects. However, IgM serum antibodies were elevated in the periodontally normal siblings of LJP patients suggesting that the formation of IgM antibodies to A. actinomycetemcomitans may precede the clinical appearance of localized juvenile periodontitis. Gingival crevicular fluid and serum antibody levels to A. actinomycetemcomitans were compared in LJP patients. Comparable titers of IgG, IgA and IgM antibodies were found in serum and gingival fluid in most subjects; however, gingival fluid samples sometimes showed higher titers than serum, likely resulting from local antibody synthesis. The value of serum antibody determinations to A. actinomycetemcomitans in the diagnosis of Actinobacillus-associated periodontitis was also assessed. The predictive value of a positive test (significantly elevated anti-A. actinomycetemcomitans IgG) was 86%, while the specificity was 89%.(ABSTRACT TRUNCATED AT 400 WORDS)

Meningitis and brain abscess due to Haemophilus paraphrophilus

A case of meningitis and brain abscess due to Haemophilus paraphrophilus in a patient with congenital heart disease is reported. The abscess communicated with the cerebral ventricular system. Although the infecting strain was found to be highly sensitive to ampicillin, the patient died despite appropriate antimicrobial therapy. Characteristics distinguishing Haemophilus paraphrophilus and related species are discussed.

Differentiation between major species of the Actinobacillus--Haemophilus--Pasteurella group by gas chromatography of trifluoroacetic acid anhydride derivatives from whole-cell methanolysates

A method based on whole-cell methanolysis and trifluoroacetic acid anhydride derivatization was developed for routine laboratory differentiation between isolates from the Actinobacillus--Haemophilus--Pasteurella group. All species, except Haemophilus aphrophilus, contained D-glycero-D-mannoheptose, although in varying concentrations. The distribution of this sugar could be used to distinguish H. aphrophilus from Actinobacillus actinomycetemcomitans, H. paraphrophilus, H. influenzae type b, Pasteurella haemolytica, P. multocida and P. ureae, and also H. influenzae type b from Pasteurellae. The pattern of major sugars in P. ureae and P. haemolytica resembled that of A. actinomycetemcomitans. Major fatty acids of the whole-cell methanolysates provided no basis of interspecies differentiation.

Rapid identification of periodontal pathogens in subgingival plaque: comparison of indirect immunofluorescence microscopy with bacterial culture for detection of Actinobacillus actinomycetemcomitans

The sensitivity of indirect immunofluorescence microscopy using specific polyclonal or monoclonal serodiagnostic reagents for Actinobacillus actinomycetemcomitans in subgingival dental plaque ranged from 82-100% as compared with culture on selective or non-selective media. This bacterium was found in 100% of the periodontally diseased sites examined in localized juvenile periodontitis patients and was statistically related to clinical indices of periodontal disease including the Gingival Index, Plaque Index, and Pocket Depth. Indirect immunofluorescence microscopy is a useful technique for the rapid and reliable determination of A. actinomycetemcomitans in human subgingival dental plaque which may be applied to the clinical diagnosis, treatment, and monitoring of periodontitis associated with A. actinomycetemcomitans.

Transmission and colonization of Actinobacillus actinomycetemcomitans in localized juvenile periodontitis patients

Actinobacillus actinomycetemcomitans is a Gram-negative oral microorganism, which has been implicated in the etiology of localized juvenile periodontitis and in severe medical infections such as bacterial endocarditis. This study evaluated the ability of periodontal probes to transmit A actinomycetemcomitans from juvenile periodontitis lesions to healthy gingival sulci in the same patient. Localized juvenile periodontitis patients exhibiting first molar and incisor alveolar bone loss and with large numbers of A actinomycetemcomitans in deep periodontal pockets were included in this study. A periodontal probe was inserted into periodontal pockets of 6 mm or greater depth. The probe was then placed into a healthy gingival sulcus of 3 mm or less, in the same subject. Fifty-five transfers by probing were made and A actinomycetemcomitans in both the donor and recipient sites was assessed by a selective culture technique. The results indicate that periodontal probes can become contaminated with A actinomycetemcomitans from juvenile periodontitis lesions during routine dental examinations and can transfer this microorganism from infected to previously uninfected sites. However, A actinomycetemcomitans inoculated into the healthy gingival sulci did not permanently colonize these sites since the organisms were eliminated within 3 weeks.

Actinobacillus actinomycetemcomitans in human periodontal disease

Recent evidence implicates Actinobacillus actinomycetemcomitans in the etiology of localized juvenile periodontitis. This paper reviews the morphological, biochemical and serological charcteristics of A. actinomycetemcomitans, evidence incriminating it as a periodontopathogen, its importance in human nonoral infections, and virulence factors which may be involved in the pathogenesis of A. actinomycetemcomitans infections. A. actinomycetemcomitans is a non-motile, gram-negative, capnophilic, fermentative coccobacillus which closely resembles several Haemophilus species but which does not require X or V growth factors. The organism has been categorized into 10 biotypes based on the variable fermentation of dextrin, maltose, mannitol, and xylose and into 3 serotypes on the basis of heat stable, cell surface antigens. A. actinomycetemcomitans' primary human ecologic niche is the oral cavity. It is found in dental plaque, in periodontal pockets, and buccal mucosa in up to 36% of the normal population. The organism can apparently seed from these sites to cause severe infections throughout the human body such as brain abscesses and endocarditis. There is a large body of evidence which implicates A. actinomycetemcomitans as an important micro-organism in the etiology of localized juvenile periodontitis including: (1) an increased prevalence of the organism in almost all localized juvenile periodontitis patients and their families compared to other patient groups; (2) the observation that localized juvenile periodontitis patients exhibit elevated antibody levels to A. actinomycetemcomitans in serum, saliva and gingival crevicular fluid; (3) the finding that localized juvenile periodontitis can be successfully treated by eliminating A. actinomycetemcomitans from periodontal pockets; (4) histopathologic investigations showing that A. actinomycetemcomitans invades the gingival connective tissue in localized juvenile periodontitis lesions; (5) the demonstration of several pathogenic products from A. actinomycetemcomitans including factors which may: (a) facilitate its adherence to mucosal surfaces such as capsular polysaccharides; (b) inhibit host defense mechanisms including leukotoxin, a polymorphonuclear leukocyte chemotaxis inhibiting factor, and a lymphocyte suppressing factor (c) cause tissue destruction such as lipopolysaccharide endotoxin, a bone resorption-inducing toxin, acid and alkaline phosphatases, collagenase, a fibroblast inhibiting factor and an epitheliotoxin.(ABSTRACT TRUNCATED AT 400 WORDS)

A longitudinal microbiological investigation of Actinobacillus actinomycetemcomitans and Eikenella corrodens in juvenile periodontitis

Longitudinal clinical and microbiological monitoring of subjects with localized juvenile periodontitis indicated that Actinobacillus actinomycetemcomitans and Eikenella corrodens were significantly associated (P less than 0.05) with active tissue destruction.

Bacteremia caused by a beta-lactamase producing Haemophilus parainfluenzae strain of a new biotype. A case report

A case of Haemophilus parainfluenzae bacteremia without known infectious focus is reported. Phenotypically, the isolated strain is a typical H. parainfluenzae except for its ability to produce indole and beta-lactamase. Beta-lactamase producing H. parainfluenzae organisms are encountered occasionally, but to the best of our knowledge this is the first reported blood culture isolate with this ability. We propose a new biotype (IV) of H. parainfluenzae to accommodate strains that are indole, urease and ornithine decarboxylase positive.

Relative proportions of Haemophilus species in the throat of healthy children and adults

To determine normal proportions of pharyngeal Haemophilus species, qualitative and quantitative mapping of the species in the pharynx of ten healthy children and ten healthy adults was carried out using a selective and a non-selective medium. Haemophilus organisms were present in all samples, comprising approximately 10% of the total cultivable flora (range 0.6-36.9%). Haemophilus parainfluenzae was a member of the normal flora throughout life, constituting 74% of pharyngeal Haemophilus organisms. Haemophilus segnis and Haemophilus paraphrophilus occurred more frequently in samples from adults, whereas Haemophilus haemolyticus was present in only one sample. Non-encapsulated Haemophilus influenzae strains, usually of multiple biotypes, were present in 80% of the children but accounted for a mean of only 1.8% of the total flora. Their number decreased with increasing age; 40% of the adults harbored Haemophilus influenzae but only of a single biotype which constituted a minor proportion of the total flora (mean 0.15%). These findings suggest that host mechanisms can influence changes in the proportions of Haemophilus influenzae strains colonizing the host.

Actinobacillus actinomycetemcomitans in human periodontal disease. Prevalence in patient groups and distribution of biotypes and serotypes within families

Actinobacillus actinomycetemcomitans is a Gram-negative oral bacterium which has been implicated in the etiology of localized juvenile periodontitis. In this study, 403 subjects from four study groups were examined for A actinomycetemcomitans in subgingival dental plaque. Samples pooled from at least six periodontal sites were included from each subject. A actinomycetemcomitans was detected in 28 of 29 localized juvenile periodontitis patients but in only 15% of the other subjects including 28 of 134 adult periodontitis patients, 24 of 142 periodontally healthy subjects and 5 of 98 insulin dependent juvenile diabetics with varying degrees of gingivitis. A actinomycetemcomitans isolates from members of five families with localized juvenile periodontitis patients were biotyped on the basis of variable fermentation of dextrin, maltose, mannitol and xylose and serotyped by indirect immunofluorescence using serotype specific rabbit antisera. Individuals within a family all harbored A actinomycetemcomitans of the same biotype and serotype. However, even in families with individuals heavily infected with A actinomycetemcomitans, some family members did not appear to be infected with the organism. The apparent poor transmissibility of A actinomycetemcomitans between individuals may, in part, explain the overall low prevalence of localized juvenile periodontitis and the familial pattern of the disease. The high prevalence of A actinomycetemcomitans in the subgingival plaque of localized juvenile periodontitis patients, compared to the much lower prevalence in other patient groups, supports the hypothesis that A actinomycetemcomitans is an etiologic agent in this periodontal disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Suppression of the periodontopathic microflora in localized juvenile periodontitis by systemic tetracycline

Since recent studies have implicated Actinobacillus actinomycetemcomitans in the etiology of localized juvenile periodontitis, this investigation determined the effectiveness of subgingival debridement, topical Betadine Solution, and systemic tetracycline in suppressing subgingival A. actinomycetemcomitans and other microorganisms. A total of 20 deep periodontal pockets and 10 normal periodontal sites of 6 localized juvenile periodontitis patients was included in the study. Each patient was treated in 3 stages over a period of 22 weeks, and the result of treatment was monitored for an additional 38 weeks. The first stage of treatment included plaque control, as well as thorough scaling and root planing, composed of at least 6 h of debridement. No concomitant periodontal surgery was performed. In the second stage, Betadine saturated cotton gauze was inserted into the periodontal pockets for 10 min. Stage 3 involved systemic tetracycline therapy (1 g/day) for 14 days. The subgingival microflora was determined at frequent intervals by selective culturing of A. actinomycetemcomitans and Capnocytophaga and by direct microscopic examination. The clinical effect was assessed by measuring changes in probing periodontal attachment level, probing periodontal pocket depth, radiographic alveolar bone mass, and other relevant clinical parameters. Scaling and root planing reduced the total subgingival bacterial counts and the proportions of certain Gram-negative bacteria, but no periodontal pocket became free of A. actinomycetemcomitans. Betadine application had little or no effect on the subgingival microflora. In contrast, tetracycline administered via the systemic route suppressed A. actinomycetemcomitans, Capnocytophaga, and spirochetes to low or undetectable levels in all test periodontal pockets. A. actinomycetemcomitans reappeared in 9 of the deep periodontal pockets after the administration of tetracycline. Most of these 9 pockets became free of detectable A. actinomycetemcomitans during the second week of tetracycline administration, whereas pockets which yielded no A. actinomycetemcomitans after tetracycline therapy became free of the organisms during the first week of tetracycline treatment. This data suggests that systemic tetracycline therapy of localized juvenile periodontitis should, as a practical rule, be continued for 3 weeks. Periodontal destruction continued in 4 deep pockets which all showed high posttetracycline A. actinomycetemcomitans counts. All 6 pockets which demonstrated a marked gain in periodontal attachment yielded no cultivable A. actinomycetemcomitans. No association was found between periodontal disease status and subgingival Capnocytophaga, spirochetes or motile rods. The present study indicates that A. actinomycetemcomitans is an important etiologic agent in localized juvenile periodontitis.(ABSTRACT TRUNCATED AT 400 WORDS)

Potential significance of colonization with beta-lactamase-producing Haemophilus parainfluenzae in children

Recent surveys in Vancouver showed most healthy children were colonized with beta-lactamase-producing Haemophilus parainfluenzae. Such organisms might alter the effects of penicillins on throat bacteria by local inactivation. To test this hypothesis in vitro, three isolates of beta-lactamase-producing Haemophilus parainfluenzae were each mixed on a membrane with ampicillin-sensitive strains of Haemophilus influenzae type b or group A Streptococcus pyogenes and exposed to ampicillin. When tested alone, susceptible strains were rapidly killed but when tested together with a beta-lactamase producer, they were protected, indicating efficient ampicillin degradation by Haemophilus parainfluenzae strains. If similar interactions occur in vivo, the effects of beta-lactams on throat bacteria could be significantly altered in the presence of beta-lactamase-producing Haemophilus parainfluenzae.

Prevalence of Eikenella corrodens in dental plaque

The prevalence of Eikenella corrodens in dental plaque and saliva samples of 282 volunteers was determined by a semiquantitative method with a selective medium. E. corrodens was recovered in 58.9% of plaque samples and 0.3% of saliva samples. This prevalence rate was not significantly altered (P greater than 0.05) by variables of sex, race, smoking habits, clinic attended by the patient, general health status, or age; however, patients 7 to 14 years old had a significantly higher prevalence rate (90.5%; P less than 0.05). E. corrodens should be considered as a potential pathogen in infections associated with and wounds inoculated by the human gingival flora.

Selective recovery of oral Capnocytophaga spp. with sheep blood agar containing bacitracin and polymyxin B

On the basis of in vitro susceptibility testing of antibiotics, dyes, and other antimicrobial agents, we developed and evaluated a medium, TBBP, for the selective isolation of oral Capnocytophaga spp. TBBP medium consists of 4% Trypticase soy agar (BBL Microbiology Systems, Cockeysville, Md.), 5% sheep blood, 0.1% yeast extract, 50 micrograms of bacitracin per ml, and 100 micrograms of polymyxin B per ml. A total of 34 Capnocytophaga stock cultures grew well on TBBP medium. Except for some streptococcal strains, TBBP medium inhibited growth of all test stock culture isolates of common oral gram-positive and gram-negative species. In a clinical study of 15 deep periodontal pockets, TBBP medium demonstrated Capnocytophaga recoverability that was similar to or higher than that shown by a nonselective blood agar medium. Typical Capnocytophaga colonial morphology enabled us to readily distinguish this organism from the few other bacteria which could grow on TBBP medium.

Selective medium for isolation of Actinobacillus actinomycetemcomitans

A selective medium, TSBV (tryptic soy-serum-bacitracin-vancomycin) agar, was developed for the isolation of Actinobacillus actinomycetemcomitans, TSBV agar contained (per liter) 40 g of tryptic soy agar, 1 g of yeast extract, 100 ml of horse serum. 75 mg of bacitracin, and 5 mg of vancomycin. The TSBV medium suppressed most oral species and permitted significantly higher recovery of A. actinomycetemcomitans than nonselective blood agar medium. The distinct colonial morphology and positive catalase reaction of A. actinomycetemcomitans easily distinguished this bacterium from Haemophilus aphrophilus, Capnocytophaga species, and a few other contaminating organisms. With the TSBV medium, even modestly equipped laboratories will be able to isolate and identify A. actinomycetemcomitans from clinical specimens.

Bactericidal effect of pooled human serum on Bacteroides melaninogenicus, Bacteroides asaccharolyticus and Actinobacillus actinomycetemcomitans

Bacteria belonging to the species B. melaninogenicus ss. melaninogenicus (two strains), B. melaninogenicus ss. intermedius (five strains), B. asaccharolyticus (seven strains), and Actinobacillus actinomycetemcomitans (four strains) were tested under anaerobic conditions for their sensitivity to the bactericidal effect of pooled human serum. The A. actinomycetemcomitans strains were not killed to any extent by the serum. Both B. melaninogenicus ss. melaninogenicus strains were killed by serum. The sensitivity to serum among the strains of B. asaccharolyticus and B. melaninogenicus ss. intermedius was diverse. There was no correlation between the sensitivity to serum among the strains and the levels of specific antibodies in the serum. The bactericidal activity of serum was only effective if the complement system was present in serum. All strains initiated activation of complement and binding of a C3 component to the cell surface both in normal and MgEGTA chelated serum. The possible role of serum bactericidal activity in the pathogenesis of oral infections is unclear.