Magnitude Of Bacteremia Research Articles

Bacteremia after supragingival scaling and dental extraction: Culture and molecular analyses.

To study the incidence and magnitude of bacteremia after dental extraction and supragingival scaling. Blood samples were taken before and 5 and 30min after dental extraction and supragingival scaling from individuals at high (n=44) or negligible risk (n=51) for infective endocarditis. The former received prophylactic antibiotic therapy. Samples were subjected to aerobic and anaerobic culture and quantitative real-time polymerase chain reaction to determine the incidence of bacteremia and total bacterial levels. Patients who did not receive prophylactic antibiotic therapy had a higher incidence of positive blood cultures (30% 5min after extraction) than patients who received prophylactic antibiotic therapy (0% 5min after extraction; p<.01). Molecular analysis did not reveal significant differences in the incidence or magnitude of bacteremia between the two patient groups either 5 or 30min after each of the procedures evaluated. Extraction was associated with higher incidence of bacteremia than supragingival scaling by blood culture (p=.03) and molecular analysis (p=.05). Molecular methods revealed that dental extraction and supragingival scaling were associated with similar incidence of bacteremia in groups receiving or not prophylactic antibiotic therapy. However, blood culture revealed that antibiotic therapy reduced viable cultivable bacteria in the bloodstream in the extraction group.

EDIN-B Promotes the Translocation of Staphylococcus aureus to the Bloodstream in the Course of Pneumonia.

It is crucial to define risk factors that contribute to host invasion by Staphylococcus aureus. Here, we demonstrate that the chromosomally encoded EDIN-B isoform from S. aureus contributes to the onset of bacteremia during the course of pneumonia. Deletion of edinB in a European lineage community-acquired methicillin resistant S. aureus (CA-MRSA) strain (ST80-MRSA-IV) dramatically decreased the frequency and magnitude of bacteremia in mice suffering from pneumonia. This deletion had no effect on the bacterial burden in both blood circulation and lung tissues. Re-expression of wild-type EDIN-B, unlike the catalytically inactive mutant EDIN-R185E, restored the invasive characteristics of ST80-MRSA-IV.

Amoxicillin and 0.12% Chlorhexidine Mouthwash May Not Be Better Than Placebo for Reducing Bacteremia in Third Molar Extractions

Article title and bibliographic information The comparative efficacy of 0.12% chlorhexidine and amoxicillin to reduce the incidence and magnitude of bacteremia during third molar extractions: a prospective, blind, randomized clinical trial. Duvall NB, Fisher TD, Hensley D, Hancock RH, Vandewalle KS. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013;115(6):752-63. Reviewers Marcelo Carlos Bortoluzzi, DDS, PhD, Fabio Andre Santos, DDS, PhD Purpose/Question The study purpose was to compare the incidence and magnitude of bacteremia after four third-molar extractions using three protocols: pre-procedure 0.12% chlorhexidine mouth rinse, prophylaxis regimen of 2 g of amoxicillin given orally, and placebo. Source of funding Government Funding: 59th Clinical Research Training Division, Lackland Air Force Base, Texas Type of study/Design Randomized controlled trial Level of evidence Level 2: Limited-quality, patient-oriented evidence Strength of recommendation grade Not applicable

Incidence and magnitude of bacteraemia caused by flossing and by scaling and root planing

Incidence and magnitude of bacteraemia caused by flossing and by scaling and root planing

The comparative efficacy of 0.12% chlorhexidine and amoxicillin to reduce the incidence and magnitude of bacteremia during third molar extractions: a prospective, blind, randomized clinical trial

The purpose of this study was to directly compare the incidence and magnitude of bacteremia of a 0.12% chlorhexidine pre-procedure rinse to the AHA and the ADA/AAOS recommended 2g amoxicillin antibiotic prophylaxis during third molar extractions. This study was a randomized, blind, placebo-controlled prospective clinical trial involving subjects assigned to a placebo, rinse, or antibiotic group. The incidence and magnitude of bacteremia were analyzed via χ(2) and Kruskal-Wallis/Friedman tests, respectively. There was no statistically significant difference in the incidence and magnitude of bacteremia between the three groups. However, the placebo group apparently resulted in the largest range and highest mean magnitude of bacteremia, followed by the rinse then the antibiotic group. The results of this novel study may reasonably conclude an oral rinse or systemic antibiotic antimicrobial intervention does not statistically reduce the incidence and magnitude of bacteremia compared to no antimicrobial intervention.

Incidence and magnitude of bacteraemia caused by flossing and by scaling and root planing

(1) Investigate incidence, magnitude and bacterial diversity of bacteraemia due to flossing compared with scaling and root planing (SRP) and (2) Identify any associations with clinical parameters. Full-mouth flossing and single quadrant SRP were performed at separate visits for 30 patients with chronic periodontitis. Baseline blood samples and at 30 s and 10 min. after completion of flossing, 5 min. after initiation of SRP and 30 s and 10 min. after completion of SRP were obtained. Total bacteraemia and viridans streptococcal bacteraemia (VSB) were investigated. Total bacteraemia incidence was 30% for flossing and 43.3% for SRP (no significant difference; p = 0.21). Flossing and SRP caused the same incidence of VSB (26.7%). Flossing caused a higher mean magnitude of total bacteraemia than SRP (7.4 ± 16.2 CFU/ml versus 2 ± 3.4 CFU/ml), but the difference was not significant (p = 0.2). Flossing caused a higher mean magnitude of VSB than SRP (1.2 ± 1.6 CFU/ml versus 0.4 ± 0.2 CFU/ml), but the difference was not significant (p = 0.09). Viridans streptococci comprised 11.4% of flossing bacteraemia isolates and 7.6% in SRP. No correlations were found between clinical parameters and incidence or magnitude of bacteraemia following flossing. Gingival inflammation was significantly associated with incidence of total bacteraemia (p = 0.01) and VSB (p = 0.001) following SRP. No correlations were found for any parameter and magnitude of total bacteraemia or VSB following SRP. No differences were found between flossing and SRP in the incidence or magnitude of total bacteraemia or VSB. This finding is important in the ongoing re-evaluation of antibiotic prophylaxis to prevent infective endocarditis.

Antibiotic Prophylaxis for Dental Procedures

The possibility that bacteremia from the mouth could cause infective endocarditis (IE) was first suggested >100 years ago, and it was later reinforced by others who targeted the viridans group streptococci from poor oral hygiene and dental extractions.1–3 These observations, along with the advent of antibiotics, eventually led to the first guidelines from the American Heart Association (AHA) in 1955. Antibiotic prophylaxis (AP) became the primary focus for prevention of IE and a standard of care for countries around the world. Controversy concerning efficacy and safety issues has existed for >30 years, and there has been a progressive reduction in the patient populations and the procedures suggested for AP since that time. Of concern, and in spite of a decreasing emphasis on AP for cardiac patients, upwards of 25 noncardiac patient populations are recommended for AP by some clinicians out of concern for systemic infections that might originate from dental procedures (eg, prosthetic joints).4 Article see p 60 Significant differences in recommendations from experts in the United States, United Kingdom, and other countries over the years highlight the lack of convincing data to either support or reject this practice. The National Institute for Health and Clinical Excellence (NICE) in the United Kingdom issued new recommendations in 2006, which took the bold step of eliminating AP altogether.5 Current (2007) AHA guidelines narrow the focus to only 4 cardiac groups at higher risk for a bad outcome from IE but who represent ≈10% of all people at risk for IE.6 The AHA-defined moderate-risk groups represent ≈90% of people at risk for IE, all of whom were recommended for AP before 2007. There are, therefore, no …

Bacteremia Associated with Toothbrushing and Dental Extraction: Lockhart PB, Brennan MT, Sasser HC, et al. Circulation 2008;117;3118–25

Antibiotic prophylaxis during dental procedures for the prevention of infective endocarditis (IE) is a widely accepted practice. In a double blind, placebo-controlled study, authors compared rates of bacteremia in individuals assigned toothbrushing, single-tooth extraction with amoxicillin prophylaxis, and single-tooth extraction with placebo. In addition, they collected data on the species of bacteria, and the duration and magnitude of bacteremia. A total of 290 patients presenting to an urgent care center underwent a total of six blood draws during one of the above procedures. The brushing, amoxicillin, and placebo groups demonstrated an overall incidence of 32%, 56%, and 80%, respectively, of bacteremia (χ2p < 0.0001). Only 2% of the placebo group and 9% of the brushing group remained bacteremic after 60 min. Most (93%) individuals cleared their bacteremia in < 20 min. The incidence of bacteremia by species identified as causing IE was 23%, 33%, and 60% among brushing, amoxicillin, and placebo groups, respectively. Nearly a third (31%) of IE-causative isolates were streptococci viridans. Amoxicillin reduced the incidence of bacteremia by 69% in extraction groups. The authors conclude that given the lack of data comparing the relative risk of IE during dental procedures to routine toothbrushing, antibiotic prophylaxis may be unnecessary.

Magnitude of bacteraemia is a predictor of mortality during 1 year of follow-up

We evaluated magnitude of bacteraemia as a predictor of mortality, comprising all adult patients with a first-time mono-microbial bacteraemia. The number of positive bottles [1 (reference), 2, or 3] in the first positive blood culture (BC) was an index of magnitude of bacteraemia. We used Cox's regression analysis to determine age and comorbidity adjusted risk of mortality at days 0-7, 8-30, and 31-365. Of 6406 patients, 31.1% had BC index 1 (BCI 1), 18.3% BCI 2, and 50.6% BCI 3. BCI 3 patients had increased risk of mortality for days 0-7 (1.30, 95% CI 1.10-1.55) and days 8-30 (1.37, 95% CI 1.12-1.68), but not thereafter. However, in surgical patients mortality increased only beyond day 7 (8-30 days: 2.04, 95% CI 1.25-3.33; 31-365 days: 1.27, 95% CI 0.98-1.65). Thus, high magnitude of bacteraemia predicted mortality during the first month with a shift towards long-term mortality in surgical patients.

O415 Magnitude of bacteraemia predicts one-year mortality

O415 Magnitude of bacteraemia predicts one-year mortality

Effect of rinsing with povidone–iodine on bacteraemia due to scaling: a randomized‐controlled trial

To investigate rinsing with povidone-iodine on bacteraemia caused by ultrasonic scaling. Sixty patients with gingivitis undertook a randomized, placebo-controlled trial in which 30 rinsed with 0.9% saline and 30 with 7.5% povidone-iodine for 2 min. before ultrasonic scaling of FDI teeth 31-35. Blood samples before and after 30 s and 2 min. of scaling were cultured by lysocentrifugation. Oral bacteraemia occurred in 33.3% of the saline group and 10% of the povidone-iodine group. Regression analysis showed that rinsing with povidone-iodine was approximately 80% more effective than rinsing with saline in reducing the occurrence of bacteraemia, with a statistically significant odds ratio (OR) of 0.189 (95% confidence intervals, OR=0.043-0.827). There were 24 oral bacterial isolates in the saline group and 3 in the povidone-iodine group. Viridans streptococci comprised 11 of the isolates in the saline group and none in the povidone-iodine group. Bacteraemia magnitude was 0.1 colony-forming units/ml in the povidone-iodine subjects and 0.1-0.7 CFU/ml in the saline group. Rinsing with 7.5% povidone-iodine reduced the incidence and magnitude of bacteraemia and eliminated viridans streptococci from such bacteraemia. Povidone-iodine rinsing may be helpful for ultrasonic scaling of gingivitis patients at risk of infective endocarditis.

Incidence of bacteremia after chewing, tooth brushing and scaling in individuals with periodontal inflammation

SCIENTIFIC RATIONALE FOR STUDY: Bacteremia occurs with various frequency after oral procedures. Periodontal disease may affect the incidence, magnitude, duration and bacterial spectrum of bacteremia. The incidence and magnitude of bacteremia after scaling was significantly higher in periodontitis than in gingivitis patients and healthy control individuals. In periodontitis patients, the magnitude of bacteremia was associated with gingival index, plaque index and number of sites with bleeding on probing, but not with probing pocket depth measurements. The prevention and treatment of periodontal diseases appear to be crucial for the prevention of bacteremia associated with oral procedures.

Attenuation of the bacterial load in blood by pretreatment with granulocyte-colony-stimulating factor protects rats from fatal outcome and brain damage during Streptococcus pneumoniae meningitis.

A model of pneumococcal meningitis in young adult rats receiving antibiotics once the infection was established was developed. The intent was to mimic clinical and histopathological features of pneumococcal meningitis in humans. The primary aim of the present study was to evaluate whether medical boosting of the peripheral neutrophil count affected the outcome of the meningitis. The risk of terminal illness over the first 7 days after infection was significantly reduced for rats who had elevated peripheral white blood cell counts after receiving granulocyte-colony-stimulating factor (G-CSF) prior to the infection compared to that for untreated rats (P = 0.039 by the log rank test). The improved outcome was associated with reduced signs of cerebral cortical damage (P = 0.008). Furthermore, the beneficial effects of G-CSF were associated with reduced bacterial loads in the cerebrospinal fluid (median, 1.1 x 10(5) versus 2.9 x 10(5) CFU/ml; P = 0.023) and in blood (median, 2.9 x 10(2) versus 6.3 x 10(2) CFU/ml; P = 0.024), as well as attenuated pleocytosis (median, 800 x 10(6) versus 1,231 x 10(6) cells/liter; P = 0.025), 24 h after the infection. Conversely, initiation of G-CSF therapy 28 h postinfection did not alter the clinical or histological outcome relative to that for non-G-CSF-treated rats. The magnitude of bacteremia and pretreatment with G-CSF were found to be prognostic factors for both outcome and brain damage. In summary, elevated neutrophil levels prior to the development of meningitis result in reduced risks of death and brain damage. This beneficial effect is most likely achieved through improved control of the systemic disease.

Pneumococcal bacteremia and focal infection in young children.

We reviewed a consecutive case series of 178 immunocompetent children aged 3-36 months without central venous lines who had blood cultures positive for Streptococcus pneumoniae by either of paired broth and quantitative culture methods. The incidence of accompanying focal infection was significantly greater in patients with > 10 colony-forming units (cfu)/mL than in patients with < or = 10 cfu/mL (30.4% vs 12.9% respectively, p = 0.04). No significant relationships existed between the magnitude of bacteremia and the age, gender, presenting temperature, interval until the blood culture turned positive, total peripheral blood white cell count, absolute neutrophil count, or absolute band count. Overall, the quantitative method detected 59/178 (33.1%) of the isolates, including five isolates (2.8%) that the broth method failed to detect.

Virulence of non-β-lactamase-mediated ampicilin-resistant Haemophilus influenzae

We questioned whether strains of ampicillin-resistant, non-beta-lactamase-producing (AmpR NBLP) Haemophilus influenzae with lower affinity penicillin-binding proteins (PBPs) might have altered virulence. The virulence of resistant transformant strains and the susceptible recipient was compared using infant rats. Following intraperitoneal inoculation, there was a significantly lower mortality rate and incidence and magnitude of bacteremia with two of three transformants compared to the recipient strain. Reduced virulence was not associated with greater bactericidal activity of serum or human neutrophils or faster clearance of the transformant following intravenous injection. Heated rat or human plasma supported exponential growth of the recipient, but not the transformant, suggesting deficient in vivo multiplication. We conclude that H. influenzae with altered PBPs are less virulent in an infant rat model which may be related to differences in in vivo growth.

Virulence of non-β-lactamase-mediated ampicilin-resistantHaemophilus influenzae

We questioned whether strains of ampicillin-resistant, non-β-lactamase-producing (AmpR NBLP) Haemophilus influenae with lower affinity penicillin-binding proteins (PBPs) might have altered virulence. The virulence of resistant transformant strains and the susceptible recipient was compared using infant rats. Following intraperitoneal inoculation, there was a significantly lower mortality rate and incidence and magnitude of bacteremia with two of three transformants compared to the recipient strain. Reduced virulence was not associated with greater bactericidal activity of serum or human neutrophils or faster clearance of the transformant following intravenous injection. Heated rat or human plasma supported exponential growth of the recipient, but not the transformant, suggesting deficient in vivo multiplication. We conclude that H. influenzae with altered PBPs are less virulent in an infant rat model which may be related to differences in in vivo growth.

Complement activation and pulmonary dysfunction in experimental Escherichia coli septicaemia

Septicaemia was induced in anaesthetized and artificially ventilated rabbits. Three groups receiving different doses of Escherichia coli 055:B5 and a control group were studied. The animals were followed for 240 min after the start of the bacterial infusion. One animal in the high-dose and one in the medium-dose group died. Septic shock developed in the high-dose group. The infusion of E. coli led to a severe, sustained neutropenia and a dose-dependent thrombocytopenia. A severe arterial hypoxaemia developed during the infusion of bacteria in three of four animals, and in one of three animals in the high- and medium-dose groups, respectively. Both the levels of C5a in plasma and the accumulation of granulocytes in the lung tissue, as assessed by a morphometric method, were dependent on the dose of bacteria. A strong positive correlation was found between levels of C5a and endotoxin. The levels of both C5a and endotoxin correlated positively to the degree of accumulation of granulocytes in the lung tissue. The results from the present study suggest that the magnitude of bacteraemia and the degree of complement activation are probably important factors determining the course and the severity of septicaemia.

A model of Staphylococcus aureus bacteremia, septic arthritis, and osteomyelitis in chickens

We studied the occurrence, magnitude, and kinetics of bacteremia and the resultant osteomyelitis and septic arthritis in an avian model of Staphylococcus aureus infection. Thirty-day-old male broiler chicks were inoculated i.v. with 10(5), 10(6), or 10(7) cfu of strain Duntravis, a beta-hemolytic, coagulase-producing, capsular type 8 isolate from the synovial fluid of a 2-year-old black boy. Bacteremia occurred in 80%, 90%, and 100% of animals inoculated with 10(5), 10(6), or 10(7) cfu, respectively. The magnitude of bacteremia in surviving, bacteremic animals increased for 96 hours after inoculation and then decreased after a plateau phase. Osteomyelitis and septic arthritis occurred only in chicks that were continuously bacteremic. The occurrence of osteomyelitis was uniform among continuously bacteremic animals and developed 1 to 23 hours after inoculation. Chickens are susceptible to systemic infections with S. aureus. Bacteremia, osteomyelitis, and septic arthritis may be induced in healthy chickens without prior manipulations that depress their resistance.

In vitro and in vivo Effects of Subinhibitory Concentrations of Clindamycin on Experimental &lt;i&gt;Klebsiella pneumoniae&lt;/i&gt; Sepsis

We studied the effect of subinhibitory doses of clindamycin on the course of experimental Klebsiella pneumoniae sepsis. Wistar rats were injected intraperitoneally with an inoculum containing 5 x 10(6) colony-forming units of K. pneumoniae resistant to clindamycin (minimum inhibitory concentration greater than 128 micrograms/ml) and then distributed to receive clindamycin 10 mg/kg/day or placebo for 10 days. All animals were bacteremic at 3 h. When the magnitude of bacteremia was compared, no difference was seen during the first 24 h; however, by 72 h the clindamycin-treated group had a significant decrease in the number of colony-forming units per milliliter blood (p less than 0.01). The mortality rate showed a tendency to decrease in the treated group (0%) as compared with the control group (30%). By 120 h, 3 of the 9 (33%) surviving animals from the control group were still bacteremic versus 0 of 11 (0%) in the clindamycin-treated group. These results suggest that subinhibitory clindamycin therapy can improve bacterial clearance and survival during the course of experimental K. pneumoniae sepsis.

The Magnitude of Bacteremia in Infants with Group B Streptococcal Disease

The Magnitude of Bacteremia in Infants with Group B Streptococcal Disease