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Biomedical subjects

Michael T Brennan

Publications and source records attributed to Michael T Brennan.

At least 19 recordsLinked to original sources
PubMed2007

The impact of oral disease and nonsurgical treatment on bacteremia in children.

BACKGROUND: The authors examine the role of dental disease and nonsurgical dental procedures in the incidence and duration of bacteremia in children. METHODS: The authors randomized a group of children to receive amoxicillin or a placebo before dental rehabilitation in an operating room setting. They collected eight blood draws at the following times: two minutes after intubation (draw 1); after dental restorations, pulp therapy and cleaning (draw 2); 10 minutes later (draw 3); and five draws during and after dental extractions (draws 4-8). The authors compared dental disease parameters and the type of dental procedures performed with the incidence and duration of bacteremia. RESULTS: The authors enrolled 100 children (aged 1-8 years) in the study. The incidence of bacteremia from draw 2 was 20 percent in the placebo group and 6 percent in the amoxicillin group (P = .07), and the incidence from draw 3 was 16 percent in the placebo group and zero percent in the amoxicillin group (P = .03). Subjects with higher gingival scores were more likely to have a bacteremia for draw 2 (P = .01). The authors found that subjects in the group with bacteremia for draw 3 had undergone more pulpotomies than did subjects in the group without bacteremia for draw 3 (3 +/- 2.5 standard deviation [SD] versus 1.5 +/- 1.6 SD, P = .04), while they found almost no differences for draw 2. CONCLUSIONS: This study suggests that gingival disease has an impact on bacteremia after dental restorations and prophylaxis. Although antibiotics have an impact, they do not eliminate bacteremia altogether.

Amoxicillin↗
PubMed2006

Growth factors and cytokines in the prevention and treatment of oral and gastrointestinal mucositis.

GOALS OF WORK: Growth factors and cytokines may be useful in preventing chemotherapy (CT)- and radiotherapy (RT)-induced oral and gastrointestinal mucositis. Two systematic reviews of the medical literature on growth factors and cytokines for the amelioration of CT- and RT-induced mucositis throughout the alimentary tract were performed by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society for Oral Oncology. The aim of these evidence-based scientific reviews was to critically evaluate the literature and create evidence-based guidelines for the use of growth factors and cytokines in the prevention or treatment of CT- and RT-induced mucositis. METHOD: The two reviews covered articles on clinical trials from January 1966 through May 2002 and preclinical studies from June 2002 through May 2005, respectively. The systematic review process was based on a well-established method for evaluating scientific literature. MAIN RESULTS: The number of articles in the first review was 29. In the second review, 23 articles were evaluated, 14 preclinical and 9 clinical studies. It was concluded from the first review that there was no sufficient evidence to provide any recommendations for clinical practice guidelines regarding growth factors and cytokines. From the second review, a guideline could be presented recommending the use of recombinant human keratinocyte growth factor-1 (palifermin) to prevent oral mucositis in patients receiving high-dose CT and total body irradiation followed by stem cell transplantation for haematological malignancies. A guideline could also be provided suggesting that granulocyte macrophage colony-stimulating factor mouthwash not be used for the prevention of oral mucositis in the transplant setting with high-dose CT and autologous or allogeneic stem cell transplantation. CONCLUSIONS: These systematic reviews have provided clarity and shown exciting new results. Further studies will provide new options for this debilitating side-effect of cancer therapy.

Animals↗
PubMed2006

Relationship between mucositis and changes in oral microflora during cancer chemotherapy.

It is thought that the incidence and severity of cancer chemotherapy-associated mucositis is caused in part by changes in the oral bacterial microflora. This systematic review examined the role of oral bacterial microflora changes in the development of oral mucositis during chemotherapy. Thirteen prospective clinical trials were identified, involving 300 patients with 13 different cancer diagnoses. There was great variability in patient populations, bacterial sample collection methodology, and oral sample sites. No clear pattern regarding qualitative and quantitative oral flora changes emerged among these studies. The most frequent Gram-negative species isolated during chemotherapy were from the Enterobacteriaceae family, Pseudomonas sp. and E. coli. The most common Gram-positive species isolated were Staphylococcus sp. and Streptococcus sp. Five studies assessed the role of oral flora changes in the genesis of oral mucosal changes, with no consensus among them. More detailed studies are required to understand the relationship between chemotherapy, alterations in the nature and magnitude of the oral microflora, and the presence of mucositis.

Agranulocytosis↗
PubMed2006

Alimentary mucositis: putting the guidelines into practice.

BACKGROUND: The Mucositis Study Group of the Multinational Association of Supportive Care in Cancer and International Society of Oral Oncology completed an evidence-based review of the literature for the management of alimentary mucositis. DISCUSSION: The present manuscript puts these guidelines into clinical practice by presenting two cases of alimentary mucositis from cancer therapy. These cases illustrate the impact of oral and gastrointestinal mucositis on patient care.

Antineoplastic Agents↗
PubMed2006

Odontogenic signs and symptoms as predictors of odontogenic infection: a clinical trial.

BACKGROUND: The authors conducted a study to determine if odontogenic signs and symptoms in the emergency department predicted the development of overt odontogenic infection at a follow-up dental visit. METHODS: One hundred ninety-five patients with odontalgia, but without overt signs of infection, were enrolled in a prospective, double-blind, randomized clinical trial. Data included dental diagnosis, pain characteristics, presence of caries and restorations, presence and size of periapical radiolucencies and other diagnostic test results. RESULTS: Thirteen of 134 subjects for whom data were available had signs of infection at the follow-up visit. Subjects in the follow-up infected (FU-I) group had larger baseline radiolucencies than did subjects in the follow-up noninfected (FU-NI) group, and restorations were more prevalent for involved teeth in the FU-I group than in the FU-NI group. CONCLUSIONS: A relationship exists between radiolucency size and the presence of amalgam restorations in patients who develop clinical signs of infection. Penicillin did not appear to influence this progression. CLINICAL IMPLICATIONS: Antibiotics are not effective in preventing the development of odontogenic infection when definitive dental therapy cannot be provided for acute pain in the absence of clinical signs of infection. Although the overall risk of developing infection is low, early treatment is indicated for teeth with larger periapical radiolucencies, amalgam restorations or both.

Abscess↗
PubMed2005

Oral manifestations of patients with lupus erythematosus.

Lupus erythematosus manifests as cutaneous variants, such as discoid lupus erythematosus or systemic lupus erythematosus. Systemic lupus erythematosus is a multisystem autoimmune disease characterized by general autoantibody production and a wide range of mucocutaneous, renal, neuropsychiatric, cardiovascular, infectious, and hematologic manifestations. This article discusses the prevalence of and considerations for oral mucosal lesions in lupus erythematosus and the impact of the various disease manifestations of systemic lupus erythematosus on dental management.

Female↗
PubMed2004

Pilot clinical trial of dehydroepiandrosterone (DHEA) versus placebo for Sjögren's syndrome.

OBJECTIVE: To screen for potential efficacy and assess feasibility and safety of dehydroepiandrosterone (DHEA) as a treatment for Sjögren's syndrome (SS). METHODS: A 24-week randomized, double-blinded, pilot trial of oral DHEA (200 mg/day) versus placebo was conducted. The primary comparison was to a hypothesized 20% placebo response rate. If 14 consecutive subjects on DHEA did not respond, a Phase III trial would be considered futile. A placebo group of 14 subjects was planned to verify placebo response rate and estimate sample size required for a definitive trial. Response criteria required 20% improvement in at least 2 of 3 domains. Analysis of covariance was used to adjust for baseline differences and for stratified randomization. Outcome measures included visual analog scale questionnaires for dry eye and dry mouth symptoms, lissamine green ocular dye staining and Schirmer I tests, stimulated salivary flow, IgG, and erythrocyte sedimentation rate (ESR). RESULTS: Randomization resulted in 14 DHEA and 14 placebo group subjects. At baseline, mean +/- SD for DHEA versus placebo groups were Schirmer I tests 4.5 +/- 4.5 versus 5.4 +/- 6.1 mm/5 minutes; Van Bijsterveld score 5.3 +/- 2.1 versus 5.5 +/- 2.2; unstimulated saliva 0.03 +/- 0.05 versus 0.04 +/- 0.10 ml/minute; IgG 1,699 +/- 749 versus 1,712 +/- 621 g/dl; and ESR 40 +/- 31 versus 44 +/- 28 mm/hour. Apart from changes over the trial in dry mouth symptoms, no significant differences were noted between the DHEA and placebo groups for dry eye symptoms, objective measures of ocular dryness, stimulated salivary flow; IgG, or ESR. Four DHEA and one placebo group patient dropped out because of adverse effects. Although 7 subjects met response criteria in the DHEA group, 5 met the criteria in the placebo group, and there was no significant difference between groups. CONCLUSION: DHEA showed no evidence of efficacy in SS. Without evidence for efficacy, patients with SS should avoid using unregulated DHEA supplements, since long-term adverse consequences of exposure to this hormone are unknown.

Adjuvants, Immunologic↗
PubMed2004

Impact of amoxicillin prophylaxis on the incidence, nature, and duration of bacteremia in children after intubation and dental procedures.

BACKGROUND: Controversy exists about the impact of prophylactic antibiotics on bacteremia after invasive dental procedures. The purpose of this double-blind, randomized, placebo-controlled study was to determine the impact of amoxicillin prophylaxis on the incidence, nature, and duration of bacteremia from nasotracheal intubation and dental procedures in children. METHODS AND RESULTS: Children were randomly assigned before surgery to the American Heart Association (AHA)-recommended dose of amoxicillin or to a placebo. Aerobic and anaerobic blood cultures were drawn at 8 specific time points after intubation, dental restorative and cleaning procedures, and before, during, and after dental extraction(s), to include blood drawings up to 45 minutes after the last extraction. Aerobic and anaerobic blood culture results were used to determine the incidence, nature, and duration of bacteremia from these procedures. For the 100 children enrolled (mean age, 3.5 years), the overall incidence of positive blood cultures, defined as at least 1 positive culture of the 8, was significantly higher in the placebo (84%) than the amoxicillin group (33%) (P<0.0001). Bacteremia occurrence rates after intubation and after dental restorations and cleaning were 18% and 20% in the placebo group and 4% and 6% in the amoxicillin group (P=0.05 and P=0.07, respectively). At 1.5 minutes after the initiation of dental extractions, bacteremia occurred in 76% of the placebo group versus 15% of the amoxicillin group (P<0.001). The majority of the 152 positive cultures and of the 29 different bacteria identified were Gram-positive cocci. Bacteremia persisted longer in the placebo group. CONCLUSIONS: Bacteremia from these procedures occurs more often, from a wider variety of bacterial species, and for a longer duration after dental extractions than previously reported in any age group. Amoxicillin has a significant impact on the incidence, nature, and duration of bacteremia after nasal intubation, dental restorative and cleaning procedures, and dental extractions.

Amoxicillin↗
PubMed2004

Etanercept in Sjögren's syndrome: a twelve-week randomized, double-blind, placebo-controlled pilot clinical trial.

OBJECTIVE: To assess the safety and potential efficacy of etanercept in the treatment of Sjögren's syndrome (SS). METHODS: This pilot study was a 12-week randomized, double-blind, placebo-controlled trial of etanercept, with 14 subjects in each group. Patients received 25 mg of etanercept or placebo (vehicle) by twice-weekly subcutaneous injection. Patients met the American-European Consensus Group criteria for SS. The primary outcome required at least 20% improvement from baseline values for at least 2 of the following 3 domains: subjective or objective measures of dry mouth, subjective or objective measures of dry eyes, and IgG level or erythrocyte sedimentation rate (ESR). RESULTS: Of the 14 patients taking etanercept, 11 had primary SS and 3 had SS secondary to rheumatoid arthritis. Baseline measures did not differ between the 2 groups. Three etanercept-treated patients and 1 placebo-treated patient did not complete the trial. Five etanercept-treated patients and 3 placebo-treated patients showed improvement from baseline in the primary outcome variable at 12 weeks, but the difference was not statistically significant. There were no significant differences between the groups for changes in subjective measures of oral or ocular symptoms (by visual analog scale), the IgG level, Schirmer I test result, van Bijsterveld score, or salivary flow. At 12 weeks, the ESR had decreased in the etanercept group compared with baseline (P = 0.004); however, the mean reduction was only 18.6%. CONCLUSION: We found no evidence to suggest that treatment with etanercept at a dosage of 25 mg twice weekly for 12 weeks was clinically efficacious in SS. A larger trial will be necessary to definitively address the efficacy of etanercept in the treatment of SS.

Arthritis, Rheumatoid↗
PubMed2004

The role of oral microbial colonization in ventilator-associated pneumonia.

The present article reviews the association between microbial colonization of the oral cavity and the lungs in critically ill patients that develop ventilator-associated pneumonia (VAP) in the intensive care unit (ICU) setting. The risk factors and microorganisms associated with VAP are presented. The role of oral colonization of VAP-associated pathogens (VAP-AP) in the development of VAP is examined. We explore the potential factors involved in oral colonization of VAP-AP, which are atypical bacteria for the oral cavity. Strategies for the prevention or moderation of oral colonization of VAP-AP have had limited success. We need a deeper understanding of the pathophysiology of VAP in order to reduce the morbidity, mortality, and cost from this common complication in ICU medicine and surgery.

Bacterial Physiological Phenomena↗
PubMed2004

Relationship between oral bacteria and hemodialysis access infection.

OBJECTIVE: Controversy exists concerning the association between oral bacteria and infection of hemodialysis (HD) shunts. The purpose of this study was to determine the extent to which oral bacteria are associated with vascular access site infections in a group of HD patients. STUDY DESIGN: Microbial blood culture data for 87 HD patients were collected: 53 via chart review (retrospective), and 34 with newly suspected vascular access infections (prospective). The primary outcome was the nature (i.e., species) of the bacteria recovered from blood cultures of subjects with vascular access infection, specifically those bacteria considered to be oral flora. RESULTS: The predominant bacteria reported to cause HD vascular access infections were Staphylococcus (48.6%) and Enterococcus (17.6%) species. Most infections occurred in hemodialysis catheters (89%) compared with AV grafts (11%) and AV fistulas (0%). The subclavian venous access (41%) and the internal jugular venous access (38.9%) were more commonly infected than other sites. None of the bacteria identified by blood cultures were considered to be oral flora. CONCLUSION: The results suggest that oral bacteria rarely, if ever, cause vascular access infections in hemodialysis patients.

Arteriovenous Shunt, Surgical↗
PubMed2004

Efficacy of penicillin for dental pain without overt infection.

OBJECTIVES: Dental pain is a common presenting symptom in the acute care setting. Even in the absence of overt infection, many physicians routinely prescribe antibiotics such as penicillin. The authors sought to test the hypothesis that penicillin is not necessary or beneficial in the treatment of undifferentiated dental pain without overt infection. METHODS: This prospective, randomized, double-blind, placebo-controlled trial was conducted at an urban teaching hospital with approximately 105,000 emergency department visits per year. A convenience sample of adult emergency department patients presenting with dental pain and no clinically overt infection was randomized to receive penicillin or placebo. A structured evaluation was performed at enrollment and again at a 5- to 7-day follow-up visit. The main outcome measure was evidence of overt dental infection at the 5- to 7-day follow-up visit. RESULTS: A total of 195 patients were enrolled. Ninety-eight (50%) were randomized to treatment with penicillin. A total of 125 patients (64%) were followed up. Outcome data were identified for nine additional study patients, who returned to the dental clinic or emergency department outside of the scheduled follow-up period and were included in the final analysis. Overall, 13 of 134 patients (9%) developed signs of infection: six of 64 (9%) from the penicillin group and seven of 70 (10%) from the placebo group (p = 0.90). There was no significant difference between the penicillin and placebo groups in baseline characteristics, medication compliance, or visual analog scale pain scores at enrollment. CONCLUSIONS: These data support the hypothesis that penicillin is neither necessary nor beneficial in the treatment of undifferentiated dental pain in the absence of overt infection.

Adult↗
PubMed2003

Sex steroid hormones in primary Sjögren's syndrome.

OBJECTIVE: To investigate the relationships between concentrations of sex hormones and measures of disease activity in patients with primary Sjögren's Syndrome (pSS). METHODS: Fifty-four women were evaluated: 39 patients (age, Q1,Q3: 57.0 yrs; 46, 66) diagnosed with pSS and 15 patients (49.0 yrs; 45, 60) who did not meet diagnostic criteria for pSS. The following measures of disease activity were assessed: serological data [antinuclear antibody, rheumatoid factor, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum immunoglobulin levels (IgG, IgA, IgM), serum protein, anti-SSA, and anti-SSB], labial minor salivary gland focus score, salivary flow rates, and objective measures of eye dryness (fluorescein corneal staining and unstimulated Schirmer's I test). Spearman correlations were calculated between these indices of disease activity and serum levels of sex hormones: dehydroepiandrosterone (DHEA), DHEA sulfate, androstenedione, testosterone, dihydrotestosterone (DHT), estrone, estradiol, and sex hormone binding globulin (SHBG). RESULTS: Numerous differences were noted between cases and controls with disease activity measures. All median values of sex steroid hormones were within the range of normal for pSS cases. Positive correlations were noted between testosterone and ESR (r = 0.36, p = 0.03), testosterone and serum protein (r = 0.37, p = 0.05), and testosterone and focus score (r = 0.44, p = 0.007). Negative correlations were present between SHBG and anti-SSA (r = -0.33, p = 0.05), SHBG and anti-SSB (r = -0.43, p = 0.009), and DHT and CRP (r = -0.41, p = 0.05). No correlations were noted between estrogens and measures of pSS disease activity. CONCLUSION: Higher levels of disease activity (ESR, serum protein, and focus score) were associated with higher concentrations of testosterone. No correlation between disease activity and estrogens was found.

Androstenedione↗
PubMed2002

Decision-making on the use of antimicrobial prophylaxis for dental procedures: a survey of infectious disease consultants and review.

There is debate concerning use of antibiotic prophylaxis before invasive dental procedures for patients at risk of acquiring distant site infection (DSI). We determined the opinions and practices of infectious disease consultants (IDCs) regarding antimicrobial prophylaxis to prevent DSIs that result from invasive dental procedures by conducting a survey of the 797 members of the Infectious Diseases Society of America Emerging Infections Network (477 members [60%] responded). Ninety percent of respondents closely follow the American Heart Association guidelines for antibiotic prophylaxis for patients with valvular heart disease who undergo invasive dental procedures. In contrast, few IDCs recommend prophylaxis for patients with lupus erythematosus, poorly controlled diabetes mellitus, dialysis catheters or shunts, cardiac pacemakers, or ventriculoperitoneal shunts. Twenty-five percent to forty percent of respondents recommended prophylaxis for prosthetic vascular grafts, orthopedic implants, or chemotherapy-induced neutropenia. We conclude that IDCs differ considerably in their assessment of the need for prophylaxis for patients who have noncardiac risk factors for DSI. These differences underscore the need for definitive studies to delineate appropriate candidates for antimicrobial prophylaxis in dental practice.

Antibiotic Prophylaxis↗
PubMed2002

Risk factors for positive minor salivary gland biopsy findings in Sjögren's syndrome and dry mouth patients.

OBJECTIVE: To investigate risk factors for positive minor salivary gland biopsy results in Sjögren's syndrome (SS) and dry mouth patients. METHODS: A total of 289 patients with dry mouth symptoms were evaluated. Potential risk factors for positive minor salivary gland biopsy results (>1 focus of lymphocytes) were studied in 2 phases. In phase 1, predictor variable candidates were identified for the test study (phase 2). Odds ratios were calculated for predictor variables. RESULTS: IgG, IgA, keratoconjunctivitis sicca, and sex, identified as the best predictor variables from phase 1 data, were included in a logistic regression model using phase 2 data. Only IgG demonstrated association with biopsy results (chi(2) = 20.4, P = 0.0001). An elevated IgG level (>1,482 mg/dl) had a high specificity (97% and 97%), high positive predictive value (PPV) (97% and 97%), but poor sensitivity (40% and 45%) in predicting positive biopsy results and SS, respectively. CONCLUSION: Elevated serum IgG levels best predicted a positive biopsy result and SS with high PPV and specificities.

Adult↗