Actinobacillus equuli ssp. haemolyticus in a semi-occlusively treated horse bite wound in a 2-year-old girl.

We report on the isolation of Actinobacillus equuli ssp. haemolyticus from wound smears of a 2-year-old girl who was admitted to the hospital due to partial amputation of the distal phalanx of her right middle finger caused by a horse bite. A. equuli typically causes diseases in horses and only very few reports describing human infections (mostly associated with wounds) are available in the literature. Interestingly, although the bacteria could be found in consecutive samples taken at different points in time, there were no signs of advancing infection or inflammation. Moreover, the fingertip regenerated after 74 days under semi-occlusive dressings with very pleasant results. For strain identification two automated systems were employed producing discrepant results: VITEK 2 described the pathogens as Pasteurella pneumotropica while MALDI-TOF MS analysis revealed A. equuli. Sequence analysis of 16S rDNA gene finally confirmed A. equuli ssp. haemolyticus as the isolated strain. The antimicrobial susceptibility testing was performed according to the CLSI criteria for Pasteurella spp. Additionally we conducted a test according to the EUCAST criteria.

Short-term effects of systemic antibiotics during periodontal healing.

OBJECTIVES: To investigate the short-term effects of nonsurgical therapy (scaling and root planing, SRP) on the subgingival microbiota in chronic (CP) and aggressive (AP) periodontal disease. METHOD AND MATERIALS: Ninety-seven CP and AP subjects underwent full-mouth SRP on 2 consecutive days. AP patients were randomly assigned to either receive systemic metronidazole plus amoxicillin (AP+AB) or were treated mechanically alone (AP). Pathogens were identified with 16S rRNA oligodeoxynucleotide probes and dot-blot hybridization before and at days 2, 3, 4, 7, 10, and 21 of healing. CP subjects were treated by scaling and root planing along with placebo tablets. RESULTS: Initially, AP cell counts were 69.9- (Porphyromonas gingivalis), 10.2- (Aggregatibacter actinomycetemcomitans), 5.7- (Tannerella forsythia), and 3.3-fold (Prevotella intermedia) enhanced compared to CP cell counts. Following SRP, immediate elimination occurred in single individuals of all three treatment groups at day 2. After SRP plus antibiotic therapy (AP+AB), the prevalence scores dropped beyond the levels of AP and CP, beginning at day 7, and remained low until day 21 (P =or< .05). Clinical healing statistically benefited from SRP with no differences among the three treatment groups. CONCLUSION: Nonsurgical therapy resulted in both a suppression and early elimination of single taxa immediately after completion of active treatment. Systemic antibiotics significantly accelerate the suppression of the periodontal microflora, but have limited effect on the elimination of target isolates during healing.

Clinical and microbiological effects of a combined mechanic-antibiotic therapy in subjects with Actinobacillus actinomycetemcomitans-associated periodontitis.

PURPOSE: To evaluate the clinical and microbiological effects of a combined mechanic-antibiotic periodontal therapy in subjects that were tested positive for subgingival Actinobacillus actinomycetemcomitans (A.a.). METHODS: The postoperative follow-up ranged from 12-115 months (average 39.2 months). This follow-up study analyzed the data of 53 subjects (37 females) aged from 16-59 years, who underwent systemic periodontal therapy with adjunctive systemic antibiotics between 1992-2001 and had their last re-examination including microbiological analysis done in 2003. The antibiotic regime was either amoxicillin/metronidazole or ciprofloxacine/metronidazole. During this study, A.a. was detected with two gene probe tests (IAI PadoTest 4.5 and DMDx/PathoTek) and cultivation on TSBV agar plates. The clinical situation was characterized with the help of pocket probing depths and subsequent categorization into three different groups (< or = 4 mm, 5-6 mm and > or = 7 mm). RESULTS: After therapy, A.a. was detected with IAI PadoTest 4.5 in a magnitude between 3.0 x 10(3) up to 2.06 x 10(5) counts per specimen in 9 out of 53 subjects. Only two subjects tested positive for A.a. with the DMDx/PathoTek-assays and the agar cultivation. The clinical situation improved significantly in all subjects after systemic periodontal therapy. The treatment results remained stable during the course of the postoperative follow-up. Concerning the clinical data, no differences were found between the subjects that were tested positive and negative for A.a in the postoperative period.

Clinical effects of scaling and root planing in adults infected with Actinobacillus actinomycetemcomitans.

The periodontal pathogen Actinobacillus actinomycetemcomitans can frequently be isolated from subgingival plaque of adults with chronic inflammatory periodontal disease and individuals with plaque-induced gingivitis. Problems with the persistence of the organism after thorough debridement of root surfaces have been reported. In the present study clinical effects of the hygienic phase of periodontal therapy in ten adult patients with moderate or advanced periodontitis harbouring A. actinomycetemcomitans were analysed. Since proper analysis of highly correlated data within a given patient is crucial for appropriate interpretation, a major objective of this study was to compare the results of different models derived from logistic regression of clinical and microbiological factors on gain or loss of clinical attachment under different assumptions. Subgingival samples from every tooth present were obtained before and 6 weeks after thorough subgingival scaling, and selectively cultivated for the organism. A relevant gain of clinical attachment of 2 mm or more was observed at a total of 36% of periodontitis sites after scaling. Overall, loss of attachment of 2 mm or more was observed at 8% sites. Most loss occurred at sites with gingival enlargement (15%), whereas 3% periodontitis sites lost 2 mm or more. In multivariate analyses erroneously assuming either independence of data or correctly considering the correlated structure of observations attachment gain was mainly associated with deep probing depths at the outset. Presence or absence of A. actinomycetemcomitans before or after therapy was not included into the periodontitis models. Also, loss of attachment of 2 mm or more after subgingival scaling was not influenced by the organism. A direct comparison of the results obtained with both approaches of logistic regression may be helpful in the assessment of the influence of the magnitude of correlation of the data on the regression coefficients.

Clinical responses to mechanical periodontal treatment in Chinese chronic periodontitis patients with and without Actinobacillus actinomycetemcomitans.

BACKGROUND: The purpose of this study was to compare 12-month clinical responses to mechanical periodontal treatment in Chinese chronic periodontitis patients at sites with and without Actinobacillus actinomycetemcomitans at baseline, and to investigate the ability of mechanical periodontal treatment to eliminate A. actinomycetemcomitans. METHODS: Nineteen patients and a total of 76 selected sites with a mean probing depth (PD) of > or = 7 mm were studied. Whole mouth presence or absence of supragingival plaque (PI%), bleeding on probing (BOP%), probing depth (PD), and probing attachment level (PAL) were recorded at six sites per tooth at baseline and after 3, 9, and 12 months. Baseline subgingival plaque samples were taken from the deepest PD site in each quadrant using sterile paper points and were cultured on TSBV plates for 5 days in a 5% CO2-air incubator. All sites received mechanical periodontal treatment, which included oral hygiene instructions and supragingival and subgingival instrumentation with or without surgical access, with maintenance care being provided once every 3 months thereafter. RESULTS: At baseline, A. actinomycetemcomitans was isolated in 13 of the 19 subjects (68%) and in 29 out of the 76 sampled sites (38%). At the end of 12 months, in three of the initially A. actinomycetemcomitans-positive subjects, A. actinomycetemcomitans was not detected in the sampled sites, while one subject, in whom A. actinomycetemcomitans was not initially found at the sampled sites was A. actinomycetemcomitans-positive at 12 months. Multi-level variance component models showed there was no statistically significant difference in all clinical parameters between A. actinomycetemcomitans-positive and -negative subjects (P > 0.05). In the sampled sites of the initially A. actinomycetemcomitans-positive subjects, the mean PD was reduced from 7.6 +/- 1.6 mm to 3.2 +/- 1.8 mm, the mean PAL gain was 1.4 +/- 2.0 mm, and the mean recession was 3.0 +/- 2.3 mm. The corresponding figures in the sampled sites of the initially A. actinomycetemcomitans-negative subjects were 7.5 +/- 1.6 mm to 2.7 +/- 1.0 mm, 2.3 +/- 2.6 mm and 2.4 +/- 2.2 mm for mean PD changes, PAL gain, and mean recession, respectively. CONCLUSIONS: Favorable clinical responses to mechanical periodontal therapy may occur in Chinese chronic periodontitis patients at sites infected with A. actinomycetemcomitans. The mere detection of subgignival A. actinomycetemcomitans does not necessarily imply poorer treatment outcomes in the control of chronic periodontitis.

Molecular approaches to the identification and treatment monitoring of periodontal pathogens.

Two different PCR-based molecular approaches, a commercial kit for detection of A. actinomycetemcomitans, P. gingivalis, P. intermedia, B. forsythus and T. denticola (Amplimedical "Paradonthosis") and a home-made multiplex PCR for A. actinomycetemcomitans, P. gingivalis and B. forsythus were compared for monitoring the efficacy of different dental treatments on localized persistent periodontal pockets. 44 sites were randomized in two treatment groups: mechanical treatment (22 control sites) and in conjunction with the application of tetracycline fibres (22 experimental sites). 40/44 sites were found positive with both tests for A. actinomycetemcomitans, P. gingivalis and B. forsythus pretheraphy. P. intermedia was detected alone in only three sites during the follow-up, while T. denticola. was always associated with the other pathogens. 20 sites were positive in conventional cultures for one to three of the pathogens. PCR-based approaches provided a sensitive and reliable method for identification and monitoring treatment of periodontal pathogens.

Bilateral endogenous endophthalmitis caused by HACEK microorganism.

PURPOSE: To report a case of bilateral endogenous endophthalmitis caused by a HACEK group organism (Actinobacillus actinomycetemcomitans). METHODS: An 85-year-old Caucasian female presented with bilateral light perception visual acuity, anterior chamber cells, hypopyon, posterior synechiae, and no red reflex. RESULTS: The patient underwent bilateral vitrectomy, with topical, intravitreal, and systemic antibiotics. Vitreous cultures revealed gram-negative cocco bacilli consistent with Actinobacillus actinomycetemcomitans. At final follow-up, visual acuity was 20/25 RE and 20/40 LE. CONCLUSIONS: Prompt diagnosis and treatment of HACEK [Hemophilus sp. (parainfluenzae, aphrophilus, paraphrophilus), Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corodens, and Kingella kingae] group bacterial endophthalmitis can yield good results.

Generalized aggressive periodontitis in a prepubertal patient: a case report.

A 10-year-old boy presented with generalized gingival inflammation, extensive alveolar bone loss, and tooth mobility. Clinical and radiographic examination supplemented by microbiologic investigation led to a diagnosis of classically termed prepubertal periodontitis (now known as generalized aggressive periodontitis). Other than severe periodontitis, the child was systemically healthy. Neither unusual infections nor abnormalities in neutrophil functions were detected. Microbiologic examinations by culture revealed the presence of the periodontal pathogen Actinobacillus actinomycetemcomitans. Treatment consisted of extraction of mobile teeth, supragingival and subgingival debridement, subgingival curettage, and root planing combined with a 1-week prescription of a combination of metronidazole and amoxicillin. Scanning electron microscopy of extracted teeth revealed hypoplastic and aplastic cementum at the periodontally exposed and intact surfaces. Clinical and microbiologic follow-up was continued over a 1-year period. No periodontal lesions have been detected, and A actinomycetemcomitans could not be isolated from the subgingival areas of the remaining teeth at the end of the first year. Since A actinomycetemcomitans was the main pathogen present in the subgingival microflora of the patient, it might play a key role in the etiology of prepubertal periodontitis.

Interleukin-10 gene therapy-mediated amelioration of bacterial pneumonia.

Respiratory infection by Actinobacillus pleuropneumoniae causes a highly pathogenic necrotizing pleuropneumonia with severe edema, hemorrhage and fever. Acute infection is characterized by expression of inflammatory cytokines, including interleukin-1 (IL-1), IL-6 and IL-8. To determine if high level production of inflammatory cytokines contributed to disease pathogenesis, we investigated if inhibiting macrophage activation with adenovirus type 5-expressed IL-10 (Ad-5/IL-10) reduced the severity of acute disease. Porcine tracheal epithelial cells infected with Ad-5/IL-10 produced bioactive human IL-10. When pigs were intratracheally infected with A. pleuropneumoniae, pigs pretreated with Ad-5/IL-10 showed a significant reduction in the amount of lung damage when compared to adenovirus type 5-expressing beta-galactosidase (Ad-5/beta-Gal)-treated and untreated pigs. In addition, serum zinc levels were unchanged, the lung weight/body weight ratio (an indicator of vascular leakage) was significantly reduced, and lung pathology scores were reduced. Myeloperoxidase activity in lung lavage fluid samples, an indicator of neutrophil invasion, was decreased to levels similar to that seen in pigs not infected with A. pleuropneumoniae. Reduction in inflammatory cytokine levels in lung lavage fluid samples correlated with the clinical observations in that pigs pretreated with Ad-5/IL-10 showed a corresponding reduction of IL-1 and tumor necrosis factor (TNF) compared with untreated and Ad-5/beta-Gal-treated pigs. IL-6 levels were unaffected by pretreatment with Ad-5/IL-10, consistent with observations that IL-6 was not derived from alveolar macrophages. Since inflammatory cytokines are expressed at high levels in acute bacterial pleuropneumonia, these results indicate that macrophage activation, involving overproduction of IL-1 and TNF, is a prime factor in infection-related cases of massive lung injury.

Actinobacillus actinomycetemcomitans in destructive periodontal disease. Three-year follow-up results.

BACKGROUND: Convincing data exist that A. actinomycetemcomitans is an etiologic agent of periodontal disease. The purpose of this longitudinal study was to evaluate A. actinomycetemcomitans as a diagnostic indicator for periodontal disease in treated and periodontally maintained patients. METHODS: Following comprehensive mechanical/surgical and supportive amoxicillin plus metronidazole therapy in 13 subjects with A. actinomycetemcomitans-associated destructive periodontal disease, we monitored subgingival A. actinomycetemcomitans at 4 individual sites in each patient up to 3 years post-therapy. The periodontal status was determined, and A. actinomycetemcomitans levels were quantitatively enumerated on TSBV agar in CFU/ml. Six patients with a persistence of subgingival A. actinomycetemcomitans at each reexamination within 3 years post-therapy were selected to be at risk for minor periodontal treatment outcomes and further recurrence of periodontal disease (test group). Seven subjects with a complete suppression of A. actinomycetemcomitans at each post-therapy visit served as controls. RESULTS: The periodontal parameters decreased from overall values of 6.39 mm (probing depth, PD) and 7.64 mm (clinical attachment level, CAL) at the outset to 3.81 mm (PD) and 5.62 mm (CAL) 2 years post-therapy (Friedman, P< or =0.05). At the 3-year reexamination, the PD/CAL scores increased to 4.03/5.78 mm. Among the 6 individuals (46%) with persistence of subgingival A. actinomycetemcomitans at the final 3-year visit (test group), periodontal status yielded increased levels of 4.45 mm (PD) and 6.60 mm (CAL). The control subjects (n = 7) revealed lower values of 3.67 mm (PD) and 5.09 mm (CAL). However, on a patient level, during the 3-year observational trial, the periodontal status of the 13 individuals was not statistically affected by subgingival infection with A. actinomycetemcomitans. CONCLUSIONS: Although in advanced periodontal disease, comprehensive mechanical and antimicrobial treatment is an appropriate regimen for sustained improvement of periodontal health, long-term control of subgingival infection with A. actinomycetemcomitans could not be achieved. In the maintenance care of destructive periodontitis, the persistence of A. actinomycetemcomitans is not a diagnostic parameter for periodontal disease.

Update on Actinobacillus Actinomycetemcomitans and Porphyromonas gingivalis in human periodontal disease.

Actinobacillus actinomycetemcomitans is an important pathogen of periodontitis in young individuals. Porphyromonas gingivalis is a major pathogen of severe adult periodontitis. A. actinomycetemcomitans and P. gingivalis can be transmitted from family member to family member and may cause periodontitis in the recipient individual. In the USA, A. actinomycetemcomitans occurs more frequently in Hispanics and Asians than in Caucasians. P. gingivalis is more common in Hispanics, Asians and Blacks than in Caucasians. A. actinomycetemcomitans and P. gingivalis strains differ in genotype, serotype, toxin and enzyme production, and cellular invasiveness. Variation in virulence may help explain differing clinical outcomes of periodontal A. actinomycetemcomitans and P. gingivalis infections. A. actinomycetemcomitans and P. gingivalis cannot be eradicated from the great majority of deep periodontal pockets by mechanical debridement alone. A. actinomycetemcomitans may be removed from subgingival sites by adjunctive systemic amoxicillin-metronidazole or other appropriate antibiotic therapies. Subgingival eradication of P. gingivalis may require periodontal surgery as well as antibiotic therapy.

Eradication of Actinobacillus actinomycetemcomitans from the oral cavity in adult periodontitis.

Eradication of Actinobacillus actinomycetemcomitans from the oral cavity seems to be a prerequisite for successful therapeutic outcome in patients periodontally infected with the organism. In view of the limited number of subgingival samples obtained in recent studies one cannot conclude, however, whether eradication has actually been achieved. In the present study clinical and microbiological parameters were monitored in 10 adult patients with A. actinomycetemcomitans-associated periodontitis during successive non-surgical and adjunctive metronidazole plus amoxicillin (or ciprofloxacin) (AB) therapy. In every patient, 13 extracrevicular samples and subgingival samples from the deepest site of every tooth present were selectively cultivated for A. actinomycetemcomitans. The organism was isolated in 47 +/- 29% subgingival and 64 +/- 31% extracrevicular samples. Six weeks following subgingival scaling, A. actinomycetemcomitans was detected in 37 +/- 30% subgingival and 55 +/- 38% extracrevicular samples (n.s.). Three months after antibiotic therapy, the organism was recovered from only 1 patient. At baseline, 7.5 +/- 4.2% sites had a probing pocket depth (PPD) > or = 7 mm. This proportion dropped to 2.3 +/- 2.4% after scaling (p < 0.05) and to 0.3 +/- 0.4% after AB (p < 0.05). The proportion of sites with clinical attachment loss (CAL) > or = 6 mm dropped from 23.3 +/- 13.3% to 17.7 +/- 13.4% (p < 0.05) and to 16.8 +/- 14.6%. Statistical analysis revealed that the organism was strongly related, at baseline, to PPD > or = 7 mm (odds ratio 9.8, p < 0.001). Six weeks after scaling, the organism was associated with CAL > or = 6 mm (odds ratio 1.8, p = 0.02). After scaling, high counts of A. actinomycetemcomitans in excess of 10(4) CFU/ml significantly interfered with attachment gain of > or = 2 mm (odds ratio 0.24, p = 0.001). Based on the present findings, eradication of A. actinomycetemcomitans seems to be possible with adjunctive antibiotic treatment. Elimination of the organism after scaling was only weakly associated with clinical improvement.

[Infectious endocarditis induced by Actinobacillus actinomycetemcomitans. 8 new cases]. / Endocardite infectieuse à Actinobacillus actinomycetemcomitans. Huit nouvelles observations.

A commensal organism of the buccal cavity, Actinobacillus actinomycetemcomitans (AAC) has been responsible for at least four new cases of infectious endocarditis by year in France. This retrospective study was based on 90 new cases of infectious endocarditis by AAC, including 8 personal observations. One third of patients had no known cardiac disease before their infectious endocarditis, the portal of entry of which was usually dental. In cases of suspected infectious endocarditis, rapid and severe weight loss (43% of cases) and, less commonly, anicteric cholestasis (8%) should alert the physician for the possible pathological role of AAC. The echocardiographic appearances are non-specific. The diagnosis is confirmed on blood cultures but the organism grows slowly in CO2 enriched atmosphere. Initially, the course of the disease was favourable in one third of patients but, in two thirds of cases, complications were observed almost renal (26%), cardiac (24%) and neurological (18%). Two thirds of patients were cured by the time they were discharged whereas the remainder had sequellae, mainly valvular and neurological. The hospital mortality was 9%; late mortality was 6%. Therefore, the prognosis of AAC endocarditis, seems to be better than that of other bacteriological forms. A combination of cephalosporin and aminoside, or even a simple third generation cephalosporin antibiotic therapy for at least 4 weeks are usually effective. The complementary surgical indications are the same as for other forms of infectious endocarditis. Prophylaxis depends on strict prophylactic amoxicillin therapy for all cardiac patients at risk of infectious endocarditis before dental treatment and on good bucco-dental hygiene.

The induction of specific protection against Actinobacillus pleuropneumoniae infection by specific DLE.

Immunoprophylactic and immunotherapeutic effects of specific actinobacillus DLE (dialysable leukocyte extract) were studied in model pigs experimentally infected with Actinobacillus pleuropneumoniae. Specific DLE used for immunoprophylactic purposes was administered intramuscularly to pigs either in two doses in combination with one dose of actinobacillus vaccine (1st group) or in a single dose (2nd group). All animals of the two experimental groups survived the intranasal A. pleuropneumoniae challenge (2 x 2 ml 2-5 x 10(10) c.f.u.) while 3 of 5 animals of the control group died of haemorrhagic-necrotic fibrinous pneumonia. DLE administered to pigs for immunotherapeutic purposes was applied intravenously in two doses 1 and 5 h after the actinobacillus challenge (1st group), and in a single dose 5 h following the challenge (2nd group). All animals of the first group survived the challenge while 3 out of 5 animals of the second group and 4 out of 5 animals of the control group died during the experiment.

Infecciones por actinobacillus actinomycetemcomitans / Infection by actinobacillus actinomycetemcomitans

El Actinobacillus actinomycetemcomitans es un cocobacilo gram (-), anaerobio facultativo que se encuentra formando parte de la flora comensal de la cavidad oral. Ha sido reconocido como patógeno principalmente en periodontitis y en forma secundaria en infecciones tales como endocarditis, sinusitis y abscesos de origen dentario. En esta oportunidad se presentan 3 casos clínicos de infecciones producidas por este agente (una sinusitis maxilar y dos abscesos de partes blandas). El tratamiento recomendado es fundamentalmente el adecuado drenaje quirúrgico asociado a un Beta lactámico (penicilina o ampicilina)

Diagnosis and treatment of localized juvenile periodontitis.

An actinomycetemcomitans can cause localized juvenile periodontitis and certain types of adult periodontitis. Optimal treatment of periodontal disease caused by this microorganism requires systemic antibiotic therapy in addition to mechanical debridement of the infected gingival tissues. Laboratory techniques are available to assist the practitioner in identifying this microorganism in dental plaque samples.