Interaction between Lactobacillus reuteri and periodontopathogenic bacteria using in vitro and in vivo (G. mellonella) approaches.

Periodontitis is a multifactorial inflammatory disease, and the major cause of tooth loss in adults. New therapies have been proposed for its treatment, including the use of probiotics such as Lactobacillus reuteri. The objective of this study was to evaluate the antimicrobial effects of L. reuteri: live, heat-killed and culture filtrate (cell-free supernatant), on periodontopathogenic bacteria (Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans) in vitro, as well as the in vivo survival curve, hemocyte density and microbial recovery using Galleria mellonella. For in vitro assays, all preparations reduced colony forming units of F. nucleatum, while only live L. reuteri reduced the growth of A. actinomycetemcomitans. All treatments reduced periodontopathogenic bacteria growth in vivo. The treatment with the supernatant increased the survival of larvae infected with F. nucleatum more than the treatment with live L. reuteri, and none of the treatments altered the survival of A. actinomycetemcomitans-infected larvae. In addition, the treatment with L. reuteri preparations did not alter the hemocyte count of F. nucleatum- and A. actinomycetemcomitans-infected larvae. This study demonstrated that L. reuteri preparations exerted antimicrobial effects and increased the survival of G. mellonella infected by F. nucleatum, although only live L. reuteri was able to reduce the growth of A. actinomycetemcomitans in vitro.

Polymicrobial Cerebral Abscess in a Child with Uncorrected Tetralogy of Fallot.

Aggregatibacter aphrophilus and Beta haemolytic Streptococci Lancefield group F are part of the normal oral flora and are known to cause endocarditis, sinusitis, empyema, meningitis and septic arthritis. They are now emerging as a cause of brain abscess particularly in patients with congenital heart diseases. We report a case of a 10-year-old boy with Tetralogy of Fallot (TOF), who presented with fever, headache and drowsiness. Culture yielded the growth of Aggregatibacter aphrophilus and Beta hemolytic streptococci Lancefield group F. He became clinically stable after treatment with ceftriaxone.

Dermacoccus sp. isolated from a brain abscess in a 4-year-old child.

Dermacoccus spp. have rarely been reported as human pathogens. We describe a case of a 4-year-old boy with congenital heart disease who was diagnosed with a brain abscess. The abscess was drained and the sample grew Streptococcus intermedius, Aggregatibacter aphrophilus and Dermacoccus sp.. Dermacoccus grew after 5 days of incubation and the patient was treated with meropenem.

An unusual case of aggregatibacter aphrophilus liver abscess.

Liver abscess of oropharyngeal origin in an immunocompetent patient is a rare condition. Furthermore, microbiologic diagnosis of liver abscess can be challenging due to the tremendous diversity of the microorganisms implicated and culture difficulties under laboratory conditions. We report a case of a previously healthy 23-year-old male, who presented multiple liver abscesses, attributed to aggregatibacter aphrophilus, an obligatory oral gram-negative microorganism, that normally is a component of the commensal oral microbiota and non-virulent. The etiopathogenic microorganism was identified after needle aspiration of a liver abscess cavity. Treatment with broad-spectrum antimicrobials and percutaneous catheter drainage under computed tomography guidance of both abscesses, resulted in full recovery. A. aphrophilus represents a rare entity of liver abscess in healthy individuals and suggests that a pathogen of oropharyngeal origin should be suspected when an overt source of infection cannot be documented.

Three cases of posterior reversible encephalopathy syndrome with chronic kidney disease triggered by infection.

Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological condition with diverse neurological manifestations. Many clinical factors are known causes of PRES, but only a few cases of PRES have been reported in patients with chronic kidney disease (CKD) and infectious disease. We describe three cases of PRES in patients with CKD triggered by various infectious diseases. Characteristic hyperintense signals on magnetic resonance imaging (MRI) indicating reversible vasogenic brain oedema in various parts of the brain were observed. To explain the pathophysiology of PRES, the hypertension/hyperperfusion and hypoperfusion/vasoconstriction theories have been proposed. Patients with CKD have many complications including uraemia, hypertension, and immunosuppression. Therefore, physicians should recognize that patients with CKD are at high risk of PRES triggered by infectious diseases and promptly diagnose PRES because immediate treatment of the triggers often leads to complete resolution.

Probiotic bacteria inhibit the bovine respiratory pathogen Mannheimia haemolytica serotype 1 in vitro.

This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two Paenibacillus polymyxa strains) against M. haemolytica were evaluated using a spot-on-lawn method. Probiotic strains were then tested for their adherence to bovine bronchial epithelial (BBE) cells and the ability to displace and compete against M. haemolytica on BBE. Except for S. thermophilus, all probiotic strains inhibited the growth of M. haemolytica, with zones of inhibition ranging between 12 and 19 mm. Lactobacillus strains and Lactococcus lactis displayed greater (P < 0·05) BBE adhesion compared with M. heamolytica (8·3%) and other probiotics (<2·2%). Strains of P. polymyxa and L. acidophilus caused the greatest reduction in M. haemolytica adherence, through both displacement and competition, compared with other probiotics. The results of this study suggest that probiotics may have the potential to colonize the bovine respiratory tract, and exert antagonistic effects against M. haemolytica serotype 1. SIGNIFICANCE AND IMPACT OF THE STUDY: A common method to control bovine respiratory disease (BRD) in feedlots is through mass medication with antibiotics upon cattle entry (i.e. metaphylaxis). Increasingly, antimicrobial resistance in BRD bacterial pathogens has been observed in feedlots, which may have important implications for cattle health. In this study, probiotic strains were shown to adhere to bovine respiratory cells and inhibit the BRD pathogen M. haemolytica serotype 1 through competition and displacement. Probiotics may therefore offer a mitigation strategy to reduce BRD bacterial pathogens, in place of metaphylactic antimicrobials.

Bartholinitis due to Aggregatibacter aphrophilus: a case report.

BACKGROUND: Aggregatibacter aphrophilus, a commensal of the oro-pharyngeal flora and member of the HACEK group of organisms, is an uncommonly encountered clinical pathogen. It has already been described as the causative agent of brain abscesses, empyema, meningitis, sinusitis, otitis media, bacteriemia, pneumonia, osteomyelitis, peritonitis, endocarditis and wound infections. Herein we report the first case of bartholinitis due to A. aphrophilus. CASE PRESENTATION: A 33-year-old woman was admitted for a 3-day genital pain without fever and urinary functional signs. The abscess was incised and drained; A. aphrophilus was the only micro-organism that grew from the pus. The patient received no antibiotics; the clinical course was favourable. CONCLUSION: This case highlights the importance of an effective treatment of recurrent bartholinitis such as a cold resection of the gland. It is presented for its rarity.

Aggregatibacter aphrophilus misidentified as Brucella spp. in an immunocompetent patient with brain abscess.

Aggregatibacter aphrophilus rarely causes brain abscesses. Here we report a case of the brain abscess caused by Aggregatibacter aphrophilus. Cultivated gram negative coccobacilli from cerebral abscess were initially misidentified as Brucella spp. because it gave false positive agglutination with anti-Brucella sera. Definite identification was made with MALDI-TOF assay. Right to left shunt through the pulmonary arteriovenous malformation was speculated to be the underlying cause for the brain abscess. The patient was treated successfully with ampicillin-sulbactam after failing ceftriaxone treatment.

Adjunct Antimicrobial Therapy and Periodontal Surgery to Treat Generalized Aggressive Periodontitis: A Case Report.

Here we report a case of generalized aggressive periodontitis treated with periodontal therapy including adjunct antimicrobial therapy and periodontal surgery. The patient was a 22-year-old woman who presented with the chief complaint of gingival recession. Baseline examination revealed generalized plaque deposition and gingival inflammation. Thirty-nine percent of the sites had a probing depth (PD) of 4-6 mm and 2% a PD of ≥7 mm; 63% exhibited bleeding on probing (BOP). Radiographic examination revealed vertical bone loss in the molars and horizontal bone loss in other teeth. Microbiological examination of subgingival plaque revealed the presence of Aggregatibacter actinomycetemcomitans and Tannerella forsythia. Oral health-related quality of life was assessed as a measure of patient-reported outcome. Based on a clinical diagnosis of generalized aggressive periodontitis, initial periodontal therapy and adjunct antimicrobial therapy were implemented. After reducing inflammation and subgingival bacteria, open flap debridement was performed for teeth with a PD of ≥4 mm. Reevaluation showed no sites with a PD of ≥5 mm, a minimal level of BOP, and a marked reduction in the level of the targeted periodontal pathogens. The patient's oral health-related quality of life was slightly worsened during supportive periodontal therapy (SPT). Implementation of adjunct antimicrobial therapy targeting periodontal pathogens and subsequent periodontal surgery resulted in improvement in periodontal and microbiological parameters. This improvement has been adequately maintained over a 2-year period. However, additional care is necessary to further improve the patient's oral health-related quality of life during SPT.

Bactericidal Effect of Erbium-Doped Yttrium Aluminum Garnet Laser and Photodynamic Therapy on Aggregatibacter Actinomycetemcomitans Biofilm on Implant Surface.

PURPOSE: Peri-implantitis is a common complication of dental implants. The first step of treatment is elimination of bacterial biofilm and disinfection of the implant surface. This study sought to compare the effects of an erbium-doped yttrium aluminum garnet (Er:YAG) laser, photodynamic therapy using an indocyanin green-based photosensitizer (ICG-based PS) and diode laser, toluidine blue O (TBO) photosensitizer and light-emitting diode (LED) light source, and 2% chlorhexidine (CHX) on biofilm of Aggregatibacter actinomycetemcomitans to sandblasted, large-grit, acid-etched (SLA) implant surfaces. MATERIALS AND METHODS: Fifty SLA implants were divided into five groups and were incubated with A actinomycetemcomitans bacteria to form bacterial biofilm. Group 1 underwent Er:YAG laser radiation (with 10-Hz frequency, 100-mJ energy, and 1-W power); group 2 was subjected to LED (with 630-nm wavelength and maximum output intensity of 2.000 to 4.000 mW/cm(2)) and TBO as a photosensitizer; group 3 was exposed to diode laser radiation (with 810-nm wavelength and 300-mW power) and ICG-based PS; and group 4 was immersed in 2% CHX. Group 5 was the control group, and the samples were rinsed with normal saline. The number of colony-forming units (CFU) per implant was then calculated. Data were analyzed using one-way analysis of variance (ANOVA), and the five groups were compared. RESULTS: Significant differences was found between the control group and the other groups (P < .01). The lowest mean of CFU per implant count was in group 4 (P < .01), and the highest mean belonged to the control group. Photodynamic therapy by TBO + LED and ICG-based PS + diode laser was more effective than Er:YAG laser irradiation in suppression of this organism (P < .01). There was no significant difference between groups 2 and 3. CONCLUSION: The antibacterial effect of 2% CHX was greater than that of other understudy methods.

Aggregatibacter aphrophilus brain abscess secondary to primary tooth extraction: Case report and literature review.

We report on a rare case of Aggregatibacter aphrophilus brain abscess of odontogenic origin in a 6-year-old previously healthy boy, who had close contact with a pet dog. The poodle was the most likely source of the infecting organism, which subsequently colonized the patient's oral cavity. The abscess was surgically removed and he recovered completely after prolonged antibiotic treatment with meropenem. We also review the relevant medical literature on A. aphrophilus pediatric brain abscesses.

Brain abscess due to Aggregatibacter aphrophilus and Bacteroides uniformis.

OBJECTIVE: The aim of this report was to describe the occurrence of a bacterial brain abscess in a healthy individual, without any predisposing condition. CASE REPORT: A thirteen-year old boy was admitted to the Department of Neurosurgery after the onset of vomiting, headache and dizziness. A neurological deficit was detected during the physical examination so urgent magnetic resonance imaging of the brain was performed, revealing an intrahemispheric, right positioned solitary expansive mass with ring enhancement. Purulent material was obtained during osteoplastic craniotomy with total extirpation of the brain abscess. Aggregatibacter aphrophilus and Bacteroides uniformis were isolated. The patient's general condition improved and the neurological deficit subsided as a result of the prompt recognition and treatment of this life threatening condition. CONCLUSION: To achieve a favourable clinical outcome, prompt recognition and surgical treatment of a brain abscess are of primary importance,followed by administration of appropriate antimicrobial therapy. To our best knowledge, this is the first report of this combination of microorganisms as the cause of a brain abscess.

Differential benefits of amoxicillin-metronidazole in different phases of periodontal therapy in a randomized controlled crossover clinical trial.

BACKGROUND: The specific advantage of administering systemic antibiotics during initial, non-surgical therapy or in the context of periodontal surgery is unclear. This study assesses the differential outcomes of periodontal therapy supplemented with amoxicillin-metronidazole during either the non-surgical or the surgical treatment phase. METHODS: This is a single-center, randomized placebo-controlled crossover clinical trial with a 1-year follow-up. Eighty participants with Aggregatibacter actinomycetemcomitans-associated moderate to advanced periodontitis were randomized into two treatment groups: group A, antibiotics (500 mg metronidazole plus 375 mg amoxicillin three times per day for 7 days) during the first, non-surgical phase of periodontal therapy (T1) and placebo during the second, surgical phase (T2); and group B, placebo during T1 and antibiotics during T2. The number of sites with probing depth (PD) >4 mm and bleeding on probing (BOP) per patient was the primary outcome. RESULTS: A total of 11,212 sites were clinically monitored on 1,870 teeth. T1 with antibiotics decreased the number of sites with PD >4 mm and BOP per patient significantly more than without (group A: from 34.5 to 5.7, 84%; group B: from 28.7 to 8.7, 70%; P <0.01). Twenty patients treated with antibiotics, but only eight treated with placebo, achieved a 10-fold reduction of diseased sites (P = 0.007). Consequently, fewer patients of group A needed additional therapy, the mean number of surgical interventions was lower, and treatment time in T2 was shorter. Six months after T2, the mean number of residual pockets (group A: 2.8 ± 5.2; group B: 2.2 ± 5.0) was not significantly different and was sustained over 12 months in both groups. CONCLUSION: Giving the antibiotics during T1 or T2 yielded similar long-term outcomes, but antibiotics in T1 resolved the disease quicker and thus reduced the need for additional surgical intervention.

Evaluation of adjunctive systemic doxycycline with non-surgical periodontal therapy within type 2 diabetic patients.

OBJECTIVES: To evaluate the effects of systemic doxycycline on clinical and microbiological parameters of diabetic subjects with chronic periodontitis. METHODS: This 9-month multi-center, randomized, parallel, single-blinded study was conducted from different hospitals in Riyadh, Saudi Arabia between April 2010 and December 2010. A total of 76 diabetic subjects with chronic periodontitis were randomized into 2 groups: control group (CG) received only scaling and root planing (SRP), and the treatment group (TG) receiving systemic doxycycline during the reevaluation visit 45 days after the completion of SRP. Probing pocket depth, clinical attachment level, gingival index, plaque index, and bleeding on probing were collected at baseline, 45 days after SRP, and one, 3, and 6 months  after the use of systemic doxycycline. Microbiological analysis comprised the detection of Tannerella forsythia (Tf), Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi) by polymerase chain reaction method. RESULTS: Sixty-eight (33 CG and 35 TG) subjects completed the study. Greater reduction in the population of Tf, Pg, and Pi were observed in TG compared with CG in the first month after the administration of systemic doxycycline. The TG showed a significant improvement in gingival index scores compared with the CG (p<0.05) by the end of the first and 6 months after the administration of doxycycline. CONCLUSION: Adjunct systemic doxycycline can be associated with a reduction of Tf, Pg, and Pi in the first month after the administration of doxycycline with an improvement in the GI. 

[Cutaneous infection with Aggregatibacter actinomycetemcomitans]. / Kutane Infektion mit Aggregatibacter actinomycetemcomitans.

BACKGROUND: Aggregatibacter actinomycetemcomitans is a small, gram-negative, non-motile, coccobacillus. Aggregatibacter actinomycetemcomitans is known to cause periodontal disease and to be associated with actinomycosis. CASE REPORT: We report a patient developed a chronic wound following trauma about the right heel. The lesion resolved after oral antibiotic therapy with cefpodoxime und surgical debridement. Bacterial cultures grew abundant Aggregatibacter actinomycetemcomitans, but no actinomyces species. OBJECTIVE: The importance of Aggregatibacter actinomycetemcomitans in chronic wounds needs to be explored.

[Clinical and microbiological effects of the initial periodontal therapy].

INTRODUCTION: Periodontitis is a destructive inflammatory disease of the tooth-supporting tissues, primarily caused by Gram-negative microorganisms. Thus, the primary objective of cause-related initial periodontal therapy is disruption and removal of the subgingival biofilm. OBJECTIVE: The aim of this study was to evaluate the clinical and microbiological effects of the initial therapy in patients diagnosed with chronic periodontitis. METHODS: Forty patients with chronic periodontitis were included in the study. As a part of the clinical assessment undertaken prior to the initial therapy, as well as one month and three months post-therapy, plaque index, gingival index, papilla bleeding index, probing pocket depth and clinical attachment level were recorded. Microbiological testing was performed prior to the initial therapy and three months after therapy. Polymerase chain reaction assays were used to determine the presence of Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans. RESULTS: All clinical parameters were significantly reduced after therapy. The prevalence of Aggregatibacter actinomycetemcomitans was reduced by 22.5%, which was a statistically significant decrease compared to the baseline. The prevalence of Porphyromonas gingivalis, Tannerella forsythensis and Prevotella intermedia tended to decrease after therapy; however, the difference did not reach statistical significance. CONCLUSION: The results of the present study demonstrated the beneficial effects of the initial periodontal therapy on both the clinical and microbiological parameters.

Are there specific benefits of amoxicillin plus metronidazole in Aggregatibacter actinomycetemcomitans-associated periodontitis? Double-masked, randomized clinical trial of efficacy and safety.

BACKGROUND: It has been suggested that prescription of amoxicillin plus metronidazole in the context of periodontal therapy should be limited to patients with specific microbiologic profiles, especially those testing positive for Aggregatibacter actinomycetemcomitans. The main purpose of this analysis is to determine if patients positive for A. actinomycetemcomitans with moderate to advanced periodontitis benefit specifically from amoxicillin plus metronidazole given as an adjunct to full-mouth scaling and root planing. METHODS: This is a double-masked, placebo-controlled, randomized longitudinal study including 41 participants who were positive for A. actinomycetemcomitans and 41 participants who were negative for A. actinomycetemcomitans. All 82 patients received full-mouth periodontal debridement performed within 48 hours. Patients then received either systemic antibiotics (375 mg amoxicillin and 500 mg metronidazole, three times daily) or placebo for 7 days. The primary outcome variable was persistence of sites with a probing depth (PD) >4 mm and bleeding on probing (BOP) at the 3-month reevaluation. Using multilevel logistic regression, the effect of the antibiotics was analyzed according to the following factors (interaction effect): A. actinomycetemcomitans-positive or -negative at baseline, sex, age, smoking, tooth being a molar, and interdental location. RESULTS: At reevaluation, participants in the test group had significantly fewer sites with a persisting PD >4 mm and BOP than control patients (P <0.01). Being A. actinomycetemcomitans-positive or -negative did not change the effect of the antibiotics. Patients benefited from the antibiotics irrespective of sex, age, or smoking status. Molars benefited significantly more from the antibiotics than non-molars (P for interaction effect = 0.03). CONCLUSIONS: Patients who were positive for A. actinomycetemcomitans had no specific benefit from amoxicillin plus metronidazole. Sites on molars benefited significantly more from the antibiotics than non-molar sites.

Aggregatibacter aphrophilus pyogenic liver abscess in an immunocompetent young woman.

Aggregatibacter aphrophilus (formerly Haemophilus aphrophilus/paraphrophilus) is a small Gram-negative coccobacillus with fastidious growth requirements. It is a normal commensal of the human oropharynx and upper respiratory tract, and it can infrequently cause invasive human diseases, including bone and joint infections and subacute infective endocarditis. Cases of liver abscess caused by Aggregatibacter aphrophilus have been sparsely recorded in the English-language literature, but have not yet been reported in Taiwan. Here we present a case of Aggregatibacter aphrophilus pyogenic liver abscess in an immunocompetent young woman. She recovered uneventfully after repeated percutaneous abscess aspiration and antibiotic treatment for 5 weeks.

PDT in non-surgical treatment of periodontitis in HIV patients: a split-mouth, randomized clinical trial.

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the clinical and microbiological effect of photodynamic therapy (PDT) in the non-surgical treatment of periodontitis in HIV patients. METHODS: Twelve HIV patients from the CEAPE/UNIP, Brazil, with periodontitis were included in this 6-month, split-mouth, double-blind, controlled clinical trial. Patients were placed in the following groups: Group SRP-scaling and root planning with an ultrasonic device (SRP); and Group SRP + PDT-SRP associated with a course of PDT with a diode laser with a wavelength of 660 nm and 0.03 W power associated with methylene blue 0.01% lasting 133 seconds. All clinical measurements (periodontal probing depth (PPD), gingival recession (GR), clinical attachment level (CAL), full-mouth plaque index (FMPI), bleeding score (FMBS)), and microbiological parameters (detection of Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), and Aggregatibacter actinomycetemcomitans (Aa)) were assessed at baseline and at 45 days, and 3 and 6 months after therapy. The ANOVA/Tukey was used for statistical analysis (α = 5%). RESULTS: There were no differences in any of the investigated parameters observed at baseline in the two groups (P > 0.05). Moreover, participants in the SRP + PDT group presented a higher PPD reduction and CAL gain than those in the SRP group at 45 days and 3 and 6 months. At 6 months, sites receiving SRP + PDT showed a significant PPD reduction of 1.4 ± 0.5 mm, while those in the SRP group showed a 0.3 ± 0.8 mm reduction (P < 0.05). The CAL gain at the sixth month was 1.3 ± 0.5 mm and 0.2 ± 0.7 mm for participants in the SRP + PDT and SRP groups, respectively (P < 0.05). Microbiologically, both therapies presented a reduction in the detection of Pg, Tf, and Aa, and there was no difference between them (P > 0.05). CONCLUSION: We concluded that PDT therapy used adjunctively to SRP could promote additional benefits in the treatment of HIV-associated periodontitis.