Inhibitory effects of propolis and essential oils on oral bacteria.

INTRODUCTION: Propolis is a natural composite balsam. In the past decade, propolis has been extensively investigated as an adjuvant for the treatment of periodontitis. This study aimed to investigate antimicrobial activities of propolis solutions and plant essential oils against some oral cariogenic (Streptococcus mutans, Streptococcus mitis, Streptococcus sanguis, Lactobacillus acidophilus) and periodontopathic bacteria (Actinomyces odontolyticus, Eikenella corrodens, Fusobacterium nucleatum). METHODOLOGY: Determination of the minimum inhibitory concentration (MIC): The antimicrobial activity of propolis and essential oils was investigated by the agar dilution method. Serial dilutions of essential oils were prepared in plates, and the assay plates were estimated to contain 100, 50, 25 and 12.5 µg/mL of active essential oils. Dilutions for propolis were 50, 25, 12.5 and 6.3 µg/mL of active propolis solutions. RESULTS: Propolis solutions dissolved in benzene, diethyl ether and methyl chloride, demonstrated equal effectiveness against all investigated oral bacteria (MIC=12.5 µg/mL). Propolis solution dissolved in acetone displayed MIC of 6.3 µg/mL only for Lactobacillus acidophilus. At the MIC of 12.5 µg/mL, essential oils of Salvia officinalis and Satureja kitaibelii were effective against Streptococcus mutans and Porphyromonas gingivalis, respectively. For the latter, the MIC value of Salvia officinalis was twice higher. CONCLUSIONS: The results indicate that propolis and plant essential oils appear to be a promising source of antimicrobial agents that may prevent dental caries and other oral infectious diseases.

Acute spontaneous suppurative thyroiditis caused by Eikenella corrodens presented with thyrotoxicosis.

Acute suppurative thyroiditis is a very rare and life-threatening endocrine emergency. Thyrotoxicosis is a rare condition accompanying acute suppurative thyroiditis. While the majority of the cases in the literature are caused by different reasons, spontaneous development is very rare. We present a patient with acute suppurative thyroiditis who presented to our clinic with thyrotoxic findings, and we compared the case to the literature. A 31-year-old male patient was admitted to our clinic with a complaint of progressive neck pain, swelling and redness on midline neck, fever, and palpitations. On physical examination, swelling, redness and tenderness were detected on the neck region that was consistent with the thyroid location. He presented with tremor on the hands, tachycardia and agitation. Thyroid function tests were compatible with thyrotoxicosis, but there were findings supporting the presence of infection in biochemistry tests. On his radiological evaluations, a heterogeneous lesion divided with small septs was observed, with consolidation areas in the left thyroid lobe. In fine needle aspiration biopsy, 2mL of purulent fluid could be aspirated due to the presence of small, separated consolidation areas. He initiated on antibiotic therapy, propranolol, steroid and symptomatic treatment. Eikenella corrodens was detected on the culture antibiogram. Antibiotic therapy was continued for 14 days due to less symptoms and better biochemical values. After treatment, the patient had normal thyroid function, had relief of fever and redness of the neck, and was followed-up. It should be kept in mind that acute suppurative thyroiditis may develop spontaneously with the findings of thyrotoxicosis, with no risk factors.

Electrospun PLA Fibers Containing Metronidazole for Periodontal Disease.

PURPOSE: Electrospun PLA fiber devices were investigated in the form of fiber mats and disks. Metronidazole was used as an active agent; its concentration was 12.2 and 25.7 wt% in the devices. METHODS: The structure was studied by X-ray diffraction and scanning electron microscopy, drug release by dissolution measurements, while the antimicrobial efficiency was tested on five bacterial strains. RESULTS: The XRD study showed that the polymer was partially crystalline in both devices, but a part of metronidazole precipitated and was in the form of crystals among and within the fibers. Liquid penetration and dissolution were different in the two devices, they were faster in disks and slower in fiber mats, due to the morphology of the device and the action of capillary forces. Disks released the drug much faster than fiber mats. Although the release study indicated fast drug dissolution, the concentration achieved a plateau value in 24 hrs for the disks; the inhibition effect lasted much longer, 13 days for bacteria sensitive to metronidazole. The longer inhibition period could be explained by the slower diffusion of metronidazole located inside the fibers of the device. CONCLUSION: The results suggest that the devices may be effective in the treatment of periodontitis.

Acute spontaneous suppurative thyroiditis caused by Eikenella corrodens presented with thyrotoxicosis / Tireoidite supurativa espontânea aguda causada por Eikenella corrodens acompanhada de tireotoxicose

ABSTRACT Acute suppurative thyroiditis is a very rare and life-threatening endocrine emergency. Thyrotoxicosis is a rare condition accompanying acute suppurative thyroiditis. While the majority of the cases in the literature are caused by different reasons, spontaneous development is very rare. We present a patient with acute suppurative thyroiditis who presented to our clinic with thyrotoxic findings, and we compared the case to the literature. A 31-year-old male patient was admitted to our clinic with a complaint of progressive neck pain, swelling and redness on midline neck, fever, and palpitations. On physical examination, swelling, redness and tenderness were detected on the neck region that was consistent with the thyroid location. He presented with tremor on the hands, tachycardia and agitation. Thyroid function tests were compatible with thyrotoxicosis, but there were findings supporting the presence of infection in biochemistry tests. On his radiological evaluations, a heterogeneous lesion divided with small septs was observed, with consolidation areas in the left thyroid lobe. In fine needle aspiration biopsy, 2mL of purulent fluid could be aspirated due to the presence of small, separated consolidation areas. He initiated on antibiotic therapy, propranolol, steroid and symptomatic treatment. Eikenella corrodens was detected on the culture antibiogram. Antibiotic therapy was continued for 14 days due to less symptoms and better biochemical values. After treatment, the patient had normal thyroid function, had relief of fever and redness of the neck, and was followed-up. It should be kept in mind that acute suppurative thyroiditis may develop spontaneously with the findings of thyrotoxicosis, with no risk factors.

RESUMO A tireoidite supurativa aguda é uma emergência endócrina muito rara e com risco de vida. A tireotoxicose é uma doença rara, que acompanha a tireoidite supurativa aguda. A maioria dos casos descritos na literatura tem diferentes causas, mas o desenvolvimento espontâneo é muito raro. Relatamos o caso de um paciente com tireoidite supurativa aguda, que veio a nossa clínica apresentando achados tireotóxicos, e o comparamos com a literatura. Trata-se de paciente do sexo masculino, 31 anos, que foi internado em nossa clínica com queixa de dor progressiva, edema e vermelhidão na linha média do pescoço, febre e palpitações. Ao exame físico, foram observados edema, vermelhidão e sensibilidade à dor na região do pescoço, consistente com a localização da tireoide. Apresentava tremor de mãos, taquicardia e agitação. Embora os exames de função tireoidiana fossem compatíveis com tireotoxicose, houve achados que sustentavam a presença de infecção nos exames bioquímicos. Nas avaliações radiológicas, observou-se lesão heterogênea dividida por pequenos septos, com áreas de consolidação no lobo tireoidiano esquerdo. Na biópsia por aspiração por agulha fina, foi possível aspirar apenas 2mL de líquido purulento, devido à presença de pequenas áreas de consolidação separadas umas das outras. Iniciaram-se antibioticoterapia, administração de propranolol e esteroides, além de tratamento sintomático. Eikenella corrodens cresceu na cultura do antibiograma. A antibioticoterapia foi estendida por 14 dias devido à melhora nos sintomas e dos valores bioquímicos. Após o tratamento, o paciente se apresentava eutireoideo, com melhora na febre e na vermelhidão no pescoço, sendo então acompanhado. Deve-se ter em mente que a tireoidite supurativa aguda pode se desenvolver espontaneamente com achados de tireotoxicose, sem nenhum fator de risco.

Severe purulent pericarditis caused by invasive Eikenella corrodens: case report and literature review.

BACKGROUND: Eikenella corrodens is a slowly growing gram-negative bacillus that can cause severe invasive disease in human. Although E. corrodens infections in various sites of human body have been well described, pericarditis caused by invasive E. corrodens has rarely been reported. CASE PRESENTATION: Here we report the case of a 63-year old male with a complaint of left shoulder pain. The patient was diagnosed as purulent pericarditis by chest computed tomography scan and ultrasound-guided pericardiocentesis, and the pathogen of E. corrodens was identified in the pericardial fluid culture. The clinical condition of the patient deteriorated quickly, and he died right after the drainage surgery even though the pathogen was sensitive to antibiotics treatment. CONCLUSION: E. corrodens is a rare pericarditis associated pathogen. Purulent pericarditis caused by E. corrodens presents atypical manifestations and rapid progression of infection in immunosuppressed individuals such as neutropenic patients. Earlier diagnosis and proper drainage surgery with effective antibiotics treatment may improve the prognosis.

Eikenella corrodens endocarditis of the tricuspid valve in an intravenous drug user.

Infective endocarditis of the tricuspid valve (TVE) occurs predominantly in selected groups of patients including intravenous drug users (IVDUs). The most often cultured pathogen in IVDUs is Staphylococcus aureus. Eikenella corrodens, normally existing as a commensal in the mouth and the upper respiratory tract, is identified as an etiologic pathogen of endocarditis very rarely. The authors describe a case of a 27-year-old male with a past history of staphylococcal TVE readmitted to hospital after 5 months due to progression of right-sided heart failure. Bacteriological work-up revealed typical features and growth of E. corrodens. In echocardiography large vegetations on the damaged tricuspid valve and massive tricuspid regurgitation were seen. The prognosis of the disease, despite introduction of appropriate antibiotic therapy, was poor as he refused to undergo cardiac surgery.

HACEK endocarditis: a review.

INTRODUCTION: The HACEK group, referring to Haemophilus spp., Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae, is a rare cause of infective endocarditis (IE). It causes the majority of Gram-negative endocarditis cases and has an excellent prognosis and simple management if properly identified. However, delay in diagnosis and associated complications can render the infection fatal. AREAS COVERED: Over the past few decades, there have been tremendous advancements in understanding the manifestations and progression of HACEK endocarditis (HE). This review tackles the epidemiology of HE, the microbiological characteristics of each organism in the HACEK group, the methods used to diagnose HE, the clinical manifestations, complications, and mortality of patients with HE, as well as the recommended treatment and preventive methods. Expert Commentary: The lack of robust randomized controlled trials in diagnosis and treatment of HE makes it difficult to determine the optimal management of such infections. Nevertheless, advancements in culturing methods have shown progress in isolating and identifying these fastidious organisms. Positive blood cultures for any of the HACEK organisms in the setting of no definite focus of infection is highly suggestive of HE. In such cases, treatment with ceftriaxone or a fluoroquinolone, even without obtaining antibiotic susceptibilities, should be initiated. Moreover, the decision to proceed with surgical intervention should be individualized. As is the case for other IE, HE requires the collaboration of a multidisciplinary team consisting of the infectious disease specialist, cardiologist, cardiothoracic surgeon, and the microbiologist.

Combinatorial effects of amoxicillin and metronidazole on selected periodontal bacteria and whole plaque samples.

OBJECTIVE: The aim of the present study was to analyze in vitro the combinatorial effects of the antibiotic combination of amoxicillin plus metronidazole on subgingival bacterial isolates. DESIGN: Aggregatibacter (Actinobacillus) actinomycetemcomitans, Prevotella intermedia/nigrescens, Fusobacterium nucleatum and Eikenella corrodens from our strain collection and subgingival bacteria isolated from patients with periodontitis were tested for their susceptibility to amoxicillin and metronidazole using the Etest. The fractional inhibitory concentration index (FICI), which is commonly used to describe drug interactions, was calculated. RESULTS: Synergy, i.e. FICI values ≤ 0.5, between amoxicillin and metronidazole was shown for two A. actinomycetemcomitans (FICI: 0.3), two F. nucleatum (FICI: 0.3 and 0.5, respectively) and one E. corrodens (FICI: 0.4) isolates. Indifference, i.e. FIC indices of >0.5 but ≤4, occurred for other isolates and the 14 P. intermedia/nigrescens strains tested. Microorganisms resistant to either amoxicillin or metronidazole were detected in all samples by Etest. CONCLUSION: Combinatorial effects occur between amoxicillin and metronidazole on some strains of A. actinomycetemcomitans, F. nucleatum and E. corrodens. Synergy was shown for a few strains only.

Efficacy of a new mouth rinse formulation based on 0.07% cetylpyridinium chloride in the control of plaque and gingivitis: a 6-month randomized clinical trial.

AIM: To assess the efficacy of a 0.07% cetylpyridinium chloride (CPC) mouth rinse in the control of plaque and gingival inflammation during a 6-month period. MATERIAL AND METHODS: Adult subjects with moderate gingivitis were selected [≥40% bleeding on marginal probing (BOMP)]. After retrieving microbiological samples and evaluating the clinical parameters (plaque, BOMP and stain indexes), a professional prophylaxis was performed and subjects were randomly assigned to the test (CPC mouth rinse) or to the placebo group. Subjects were re-assessed after 3 and 6 months. RESULTS: A total of 67 patients (35 test, 32 placebo) were included in the analysis. At 6 months, intra-group significant plaque reductions were observed in the test group (0.691, p < 0.001), but not in the placebo (0.181, p = 0.653). At 6 months, the mean BOMP values were lower in the test group (p = 0.052). Changes between baseline and 6 months were significantly higher in the test group both for plaque (p = 0.002) and BOMP (p = 0.037) when compared with the placebo. A microbiological impact was observed in the test group, especially for Prevotella intermedia. CONCLUSION: The evaluated 0.07% CPC-based mouth rinse, used three times per day adjunctively to mechanical tooth cleaning, prevents plaque accumulation and gingival inflammation, as compared to the placebo, for at least 6 months.

The effects of stress hormones on growth of selected periodontitis related bacteria.

The focus of this study was to examine in vitro the effects of stress hormones (catecholamines: epinephrine, norepinephrine, dopamine and hydrocortisone: cortisol) on the growth of four anaerobic species of periodontitis-related bacteria (Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia and Tannerella forsythia) and one facultative anaerobic species (Eikenella corrodens). Bacterial growth was determined by two different methods: fluorescence in situ hybridization (FISH), and the viable count by culture method. To simulate stress, each single strain was grown in a special growth medium with three different concentrations of each hormone, using an anaerobic chamber at 37 °C. Growth of F. nucleatum increased in the presence of all stress hormones. Growth of P. gingivalis was not significantly influenced by any hormone. Growth of P. intermedia and E. corrodens was inhibited by almost all stress hormones tested. Both methods of analysis revealed that the highest concentrations of norepinephrine and cortisol increased the growth of T. forsythia. Different hormones have a different effect on the growth of periodontitis-related bacteria in vitro. It appears that bacterial viability is more strongly influenced than is bacterial metabolic activity. The growth of F. nucleatum particularly and partially of T. forsythia is increased by several stress hormones and may have an additional negative impact on periodontal disease.

LuxS affects biofilm maturation and detachment of the periodontopathogenic bacterium Eikenella corrodens.

Previously, we reported that biofilm formation of Eikenella corrodens is regulated by autoinducer-2 (AI-2), based on observations that biofilm-forming efficiency of ΔluxS mutant was greater than that of the wild type (Azakami et al., J. Biosci. Bioeng., 102, 110-117, 2006). To determine whether the AI-2 molecule affects biofilm formation directly, we added purified AI-2 to luxS mutant and wild-type E. corrodens and compared biofilm formations by using a static assay. Results indicated that biofilm formation in E. corrodens was enhanced by the addition of AI-2. We also compared the biofilms formed by flow cell system for the luxS mutant and the wild type by using scanning electron microscopy and confocal laser scanning microscopy. The number of viable bacteria in the luxS mutant biofilm was dramatically reduced and more sparsely distributed than that of the wild type, which suggested that AI-2 might enhance the mature biofilm. Conversely, further analysis by modified confocal reflection microscopy indicated that the wild-type biofilm was matured earlier than that of the luxS mutant, and became thinner and more sparsely distributed with time. These data suggest that LuxS may facilitate the maturation and detachment of biofilm in E. corrodens.

Adjunctive azithromycin in the treatment of aggressive periodontitis: microbiological findings of a 12-month randomized clinical trial.

OBJECTIVES: To compare the subgingival microbiological outcomes of azithromycin or placebo as adjuncts to scaling and root planing (SRP) in the treatment of aggressive periodontitis (AgP), and to secondarily evaluate the microbiological effect of supragingival scaling in AgP patients. METHODS: Twenty-four AgP subjects 13-26 years of age received a 15-day programme of supragingival scaling (SC) and were then randomly assigned to SRP with systemic azithromycin or placebo. Subgingival samples were taken with sterile paper points at baseline, 15 days after SC, and at 3, 6 and 12 months following SRP. Microbiological analysis was performed by the checkerboard DNA-DNA hybridization. RESULTS: Changes in bacterial levels from baseline to 15 days after SC were similar in the 2 groups. When subjects were analysed as a single group, significant reductions after SC were observed for Actinomyces gerencseriae, Capnocytophaga ochracea, and Treponema denticola. During the 12-month follow-up, levels of most of the bacteria decreased in both groups in a similar pattern. For instance, Actinomyces israelli, Veillonella parvula, Streptococcus gordonii, C. ochracea, Eikenella corrodens, Eubacterium nodatum, Fusobacterium periodonticum and Fusobacterium nucleatum ssp. polymorphum decreased significantly within the groups. CONCLUSIONS: Azithromycin was ineffective in lowering the subgingival levels of important putative periodontal pathogens in young AgP subjects compared to placebo. CLINICAL SIGNIFICANCE: Scaling and root planing with adjunctive systemic azithromycin provides little additional benefit compared to placebo in reductions of major subgingival periodontal pathogens.

The inhibitory effects of catechins on biofilm formation by the periodontopathogenic bacterium, Eikenella corrodens.

Eikenella corrodens is a periodontopathogenic bacterium that forms biofilm even by itself. In this study, we investigated the inhibitory effects of catechins on E. corrodens biofilm formation. Biofilm formation was inhibited by the addition of 1 mM of the catechins with the pyrogallol-type B-ring and/or the galloyl group. The catechins with the galloyl group were effective at smaller doses than those with only the pyrogallol-type B-ring. An inhibitory effect was observed even when these catechins and gallic acid were added at sub-minimal inhibitory concentration (MIC) or at concentrations that showed no bactericidal effect. These results suggest that some catechins at sub-MIC might inhibit biofilm formation. No inhibitory effect of catechins at sub-MIC on biofilm formation was observed in the luxS deletion mutant. Our studies suggest that some species of catechins with the galloyl group affect autoinducer 2-mediated quorum sensing and thereby inhibit biofilm formation by E. corrodens.

Infective endocarditis--a tale of two cases and the lessons (re)learned.

Infective endocarditis due to uncommon organisms or at uncommon sites presents a diagnostic challenge. Because signs and symptoms can be nonspecific and vary greatly, a high index of suspicion is necessary. We have recently treated two such cases, one due to HACEK organism (Eikenella corrodens) in a patient with established valvular heart disease and other of right sided endocarditis due to Pseudomonas aeruginosa. This report describes the diagnostic difficulties faced.

A pediatric patient with acute suppurative thyroiditis caused by Eikenella corrodens.

A previously healthy 6-year-old boy had continuous fever for 6 days before admission to our hospital. His general condition was good except for pyrexia. The left lobe of the thyroid gland was swollen, red, hot, and tender, and neck movement was limited. The provisional diagnosis was upper respiratory tract infection. We demonstrated the existence of an orifice of the left piriform sinus by esophagography in this case, and made a diagnosis of acute suppurative thyroiditis caused by a piriform sinus fistula in the hypopharynx. The causative organisms of acute suppurative thyroiditis include Peptostreptococcus, Staphylococcus haemolyticus, and α-streptococcus, but the organisms responsible are commonly undetectable in clinical cases. We detected Eikenella corrodens in the present patient. Although Eikenella species occasionally causes acute suppurative thyroiditis in adults, it is rare for this to happen in pediatric patients. Antibiotics were administered for 7 days. We also performed aspiration of the abscess on the 8th day of the illness. The abscess was reduced in size and tenderness was relieved after aspiration. In conclusion, if a pediatric patient has swelling, heat, tenderness, and redness of the anterior neck, we should keep in mind acute suppurative thyroiditis and the possibility of a fistula. If there is an abscess, we should immediately perform aspiration, culture, and isolation, and choose the appropriate antibiotics for the causative bacteria.

The antimicrobial efficacy of commercial dentifrices.

This investigation compared the effects of a fluoride dentifrice and toothpastes formulated with antimicrobial ingredients (stannous fluoride and triclosan/copolymer) on oral micro-organisms, including those found in samples taken from the human oral cavity. Microbiological techniques determined the minimum inhibitory concentrations (MICs) of each dentifrice necessary to inhibit the growth of bacterial strains from the healthy oral cavity, as well as those found in dental caries, periodontal disease, and halitosis. Ex vivo studies utilized oral rinse samples and supragingival plaque from adults to determine antimicrobial effects on the entire microbial diversity of these samples, including biofilm-derived micro-organisms. The triclosan/copolymer dentifrice demonstrated the lowest MICs and significantly inhibited Gram-positive and Gram-negative bacteria (including the periodontal pathogens Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum). In the ex vivo tests, the triclosan/copolymer dentifrice demonstrated substantial inhibition in the oral rinse samples over each treatment period (p > 0.0005) as compared to either the fluoride or stannous fluoride dentifrices. Similarly, the triclosan/copolymer dentifrice demonstrated the highest inhibition of micro-organisms in the supragingival plaque biofilm (p < 0.0005). No significant differences were observed between the fluoride and stannous fluoride dentifrices (p > 0.5).

Photodynamic therapy as an adjunct to non-surgical periodontal treatment: a randomized, controlled clinical trial.

BACKGROUND: Recent preclinical and clinical data have suggested a potential benefit of photodynamic therapy (PDT) in the treatment of periodontitis. However, there are very limited data from controlled clinical trials evaluating the effect of PDT in the treatment of periodontitis. The aim of this study was to evaluate the clinical and microbiologic effects of the adjunctive use of PDT to non-surgical periodontal treatment. METHODS: Twenty-four subjects with chronic periodontitis were randomly treated with scaling and root planing followed by a single episode of PDT (test) or scaling and root planing alone (control). Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing depth (PD), gingival recession, and clinical attachment level (CAL) were measured at baseline and 3 and 6 months after therapy. Primary outcome variables were changes in PD and CAL. Microbiologic evaluation of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia (previously T. forsythensis), Treponema denticola, Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens, and Capnocytophaga spp. was performed at baseline and 3 and 6 months following therapy by using a commercially available polymerase chain reaction test. RESULTS: At 3 and 6 months after treatment, there were no statistically significant differences between the groups with regard to CAL, PD, FMPS, or microbiologic changes. At 3 and 6 months, a statistically significantly greater improvement in FMBS was found in the test group. CONCLUSION: The additional application of a single episode of PDT to scaling and root planing failed to result in an additional improvement in terms of PD reduction and CAL gain, but it resulted in a significantly higher reduction in bleeding scores compared to scaling and root planing alone.