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Prospective study of bacteremia rate after elastic band ligation and sclerotherapy of esophageal varices in patients with hepatosplenic schistosomiasis.

BACKGROUND: Esophageal band ligation is considered to be as efficient as endoscopic sclerotherapy, with a lower complication rate, including bacteremia. There are few studies comparing the two methods. The aim of this study was to compare the incidence of bacteremia after both treatments in patients with portal hypertension secondary to schistosomiasis. METHODS: Endoscopic sclerotherapy and band ligation were performed using standard techniques. Blood samples were obtained 5 and 30 minutes after endoscopic band ligation or sclerotherapy and cultured for aerobic and anaerobic organisms. RESULTS: In the sclerotherapy group 2 of 43 (4.6%) blood cultures were positive (Peptostreptococcus sp and Streptococcus mitis). A similar result was obtained in the band ligation group: 2 of 35 (5.7%) had positive cultures, both with Staphylococcus aureus. CONCLUSIONS: There is no difference in the frequency of bacteremia after treatment of esophageal varices with endoscopic sclerotherapy or endoscopic band ligation in patients with portal hypertension secondary to schistosomiasis.

Adult↗

[Clinical results of resection arthroplasty for infected shoulder arthroplasty].

PURPOSE OF THE STUDY: Infection is a rare complication of shoulder arthroplasty. Various therapeutic solutions have been proposed: antibiotics alone, one-stage or two-stage reimplantation, surgical or arthroscopic cleaning without prosthesis removal, scapulohumeral arthrodesis or simple arthroscopic resection. We evaluated the mid-term clinical outcome after resection arthroplasty for the treatment of infected shoulder arthroplasty. MATERIAL AND METHODS: The series included ten infected arthroplasties in ten patients. Mean duration of implantation was two years seven months (range nine months to five years). Bacteriological diagnosis was established from intraoperative articular samples or systematic samples taken during surgical revision procedures: meti-S Staphylococcus aureus strains (n=4), coagulase-negative Staphylococcus (n=5 including three S. epidermidis) Streptococcus mitis (n=1) and Citrobacter koseri (n=1). The mean Constant score before revision was 58 (range 23-77). Subjective patient satisfaction before surgical revision was rated good in six cases, fair in one and poor in three. Surgery associated removal of the implant, complete resection of the cement, resection of the fistular tracts, wide debridement of infected tissues and total synovectomy. RESULTS: Patients were seen at an average follow-up of three years eight months. The objective functional outcome measured with the Constant score was only fair, 28 points (range 20.6-36), and corresponded to a loss of 29 points compared with the preoperative score. This was explained mainly by lower scores for joint motion, function and muscle force but with persistently satisfactory scores for pain. All patients remained pain-free (daytime and nighttime). Patient satisfaction was rated good for two, fair for five and mediocre for three. Clinical and biological proof of eradicated infection was obtained in all patients. DISCUSSION: Infection remains a serious devastating problem for shoulder arthroplasty with an important functional impact. Resection only has a modest clinical effect. Precise identification of the causal germ with institution of adapted antibiotic therapy is required for eradication of the infection. Early diagnosis is probably the most important parameter affecting clinical outcome and surgical options. Functional results after resection arthroplasty are modest. This procedure should be reserved for patients with reduced functional demands. Improved management of the infectious load and reduction of diagnostic delay should help improve functional outcome and favor use of stow-stage procedures for reinsertion.

Aged↗

[Usefulness of bronchoalveolar lavage in the renal transplant patient with suspected respiratory infection].

In this retrospective study we aimed to assess the diagnostic yield of bronchoalveolar lavage (BAL) in kidney transplant patients who were suspected of having severe respiratory infection or in whom empirical antibiotic treatment had failed. All BAL procedures performed on kidney transplanted patients suspected of having respiratory infections between January 1, 1988 and July 31, 1996 were analyzed. BAL was carried out in the standard way and samples were sent for cytologic and bacteriologic study. Thirty-three patients with a mean age of 48.5 years were enrolled. All had been receiving immunosuppressive treatment and the mean time following transplantation was 320 days. Thirty-one had received antibiotic treatment before BAL. BAL was positive for 21 of the 33 patients (64%). Twenty-two pathogens were identified: 6 Pneumocystis carinii, 4 Cytomegalovirus, 3 Mycobacterium tuberculosis, 2 Aspergillus fumigatus, 2 Herpes simplex type I, 1 Streptococcus pneumoniae, 1 Staphylococcus aureus, 1 Streptococcus mitis, 1 Legionella pneumophila, 1 Legionella longbeachae. BAL was negative for 12 patients, of whom 8 were tentatively diagnosed of bacterial infection, 3 of acute pulmonary edema and one of pulmonary infarction. Based on the results, therapy was changed for 20 patients (61%), 19 (58%) because an unsuspected pathogen was identified and 1 because treatment could be simplified. The diagnostic yield of BAL is high (64%) in kidney transplant patients suspected of respiratory infection and is useful for managing such cases, as evidenced by the fact that a high proportion (19/33) of our patients were infected by pathogens not covered by empirical treatment.

Adolescent↗

Oral bacteria resistant to mercury and to antibiotics are present in children with no previous exposure to amalgam restorative materials.

Dental plaque from 76 children without amalgam restorations was screened for bacteria resistant to mercuric chloride. Seventy-one per cent of the children harboured mercury-resistant oral bacteria and the median percentage of the total oral microflora resistant to mercuric chloride was 0.007% (range 0-5.3%). Eighty-seven mercury-resistant bacteria were isolated and 86% of these were streptococci with Streptococcus mitis predominating. Sixty per cent of the mercury-resistant isolates were also resistant to at least one of the four antibiotics tested (penicillin, ampicillin, erythromycin and tetracycline) with resistance to tetracycline (40% of isolates) most frequently encountered.

Anti-Bacterial Agents↗

Bacteriological study of root canals associated with periapical abscesses.

OBJECTIVE: The aim of this study was to identify microorganisms from root canals with periapical abscesses and to ascertain the susceptibility of Peptostreptococcus prevotii and Fusobacterium necrophorum to antimicrobials. Study design Thirty root canals were microbiologically sampled by using sterile paper points. The concomitant microorganisms were identified through the use of established methods. The susceptibility of P prevotii and F necrophorum to antimicrobials was evaluated by using the E test method. RESULTS: A total of 117 different bacterial strains were recovered, including 75 strict anaerobes or microphilic species. The most frequently isolated strict anaerobes were P prevotii, Peptostreptococcus micros, and F necrophorum. Facultative bacteria such as Gemella morbillorum and Streptococcus mitis were also found, albeit less frequently. The data revealed that P prevotii and F necrophorum were susceptible to the tested antibiotics. CONCLUSIONS: Gram-positive anaerobic bacteria predominate in the mixed microbiota of root canals with periapical abscesses. Moreover, P prevotii and F necrophorum are susceptible to the tested antibiotics.

Adolescent↗

A dangerous dilemma: management of infectious intracranial aneurysms complicating endocarditis.

A 41-year-old right-handed man with bicuspid aortic valve and a 3-month history of chronic fever and weight loss presented with sudden onset of severe headache. Computerised tomography of the head revealed a right basal ganglia haemorrhage. Further investigation documented Streptococcus mitis bacteraemia, a fusiform right middle cerebral artery aneurysm, and an abscess at the base of the anterior leaflet of the mitral valve. The patient subsequently died when repeat aneurysmal haemorrhage resulted in cerebral herniation and brain death while on antibiotic therapy. Infectious intracranial aneurysms (IIAs) are uncommon but severe complications of bacterial endocarditis. Several case series have been published evaluating the management of IIAs, but no randomised controlled trials exist to guide treatment decisions. Improved diagnostic techniques, microvascular neurosurgical approaches, and endovascular therapies hold the promise of improved outcomes in the future. This difficult case is used to show an approach towards the management of IIAs complicating bacterial endocarditis based on a review of the published work.

Adult↗

Effect of hydrophobicity on in vitro streptococcal adhesion to dental alloys.

Non-specific interactions such as electrostatic interactions, and surface free energy are of importance in bacterial adhesion to dental surfaces as they determine whether or not bacteria are attracted to the surface. The relationship between adherence of Streptococcus mitis, S. mutans, S. oralis and S. sanguinis on precious and non-precious dental alloys, and the bacterial and alloy surface hydrophobicities (a measure of the surface free energy) was studied. The number of adhering bacteria was determined by fluorescence microscopy counts. The hydrophobicity of the bacteria and alloy surfaces were evaluated by adhesion to hexadecane and water contact angles, respectively. Our results showed that (i) the surfaces of the tested alloys were hydrophobic, (ii) S. sanguinis, S. mutans and S. oralis were hydrophobic, and (iii) S. mitis was hydrophilic. S. oralis, the more hydrophobic strain, demonstrated the highest adherence on the tested materials, whereas S. mitis adhered least on the hydrophobic surfaces. For the tested alloys, bacterial adherence was highest for the high gold content alloy, and lowest for the non-precious alloy. Our results showed that for the tested bacterial strains, there was a significant correlation between bacterial adhesion and substratum hydrophobicity: hydrophobic metal surfaces favor adhesion of hydrophobic bacteria.

Journal Article↗

Abiotrophia species in early dental plaque.

The most characteristic traits that distinguish Abiotrophia strains from other streptococci are nutrient requirements, satellitism and pyrrolidonyl arylamidase activity. The presence of Abiotrophia strains was studied in early dental plaque formed on sucrose-containing and sucrose-free (glucose-containing) diets. The isolates were from 0- to 3-day dental plaque formed on the buccal surface of a lower premolar in six subjects. Identification of Abiotrophia strains was based on their pyrrolidonyl arylamidase activity. They were among the predominant cultivable microorganisms isolated from diluted suspensions of early dental plaque formed on both diets. Using biochemical tests without testing for pyrrolidonyl arylamidase activity, the Abiotrophia strains would be biochemically identified as Streptococcus mitis or unidentified streptococci, and many isolates first classified as unidentified streptococci were Abiotrophia strains. Generally, identifications using partial 16S rRNA sequences confirmed the identifications obtained biochemically. However, Abiotrophia elegans and Gemella strains were biochemically identified as Abiotrophia adiacens. Abiotrophia strains produce hydrogen sulfide, which may influence the metabolism and ecology of dental plaque and act as a virulence factor in periodontal disease. They are not able to grow on tryptic soy agar. In the present study, some S. mitis strains were not able to grow on mitis salivarius agar, and some Abiotrophia strains were able to grow on this medium. These observations indicate that the use of these media for estimation of total viable counts and number of streptococci introduces systematic error in studies of microorganisms in dental plaque.

Aminopeptidases↗

Clinical and microbiological findings on newly inserted hydroxyapatite-coated and pure titanium human dental implants.

The clinical and microbiologic features of 30 hydroxyapatite-coated root-form endosseous dental implants (Tri-Stage) were compared to 10 similar pure titanium implants without hydroxyapatite coatings. In 7 of 9 partially edentulous patients studied, pure titanium fixtures were placed adjacent to hydroxyapatite-coated implants. Implants in the maxilla were submerged beneath mucosal tissues after implant placement for a minimum of 6 months, and in the mandible for at least 4 months. All patients were prescribed short-term beta-lactam antibiotic therapy after fixture placement, and 8 of 9 used chlorhexidine mouthrinses after fixture exposure. Clinical and microbiological examination was carried out 7-10 months after fixed prosthetic loading of the implants. Clinical measurements included the gingival index, plaque index, bleeding on probing and peri-implant probing depths determined with the Florida Probe system. Subgingival microbial samples were collected with paper points and transported in VMGA III. Specimens were examined by direct phase-contrast microscopy and were plated onto nonselective and selective culture media for anaerobic and aerobic incubation. No significant mean clinical or microbiological differences were found between the implant types, although one hydroxyapatite-coated implant exhibited deep probing depths, bleeding on probing and marked radiographic crestal bone loss. Streptococcus sanguis and Streptococcus mitis were the most predominant organisms recovered from clinically stable implants, whereas high proportions of Fusobacterium species and Peptostreptococcus prevotii were isolated from the ailing hydroxyapatite-coated implant. One or more implants in 8 of the study subjects yielded enteric rods, pseudomonads, enterococci or staphylococci. The prognosis of implants with varying early microbiotas needs to be established in longitudinal studies.

Aged↗

Totally implantable central venous access ports for high-dose chemotherapy administration and autologous stem cell transplantation: analysis of overall and septic complications in 68 cases using a single type of device.

Sixty-eight patients suffering from breast cancer, ovarian cancer, lymphoma or multiple myeloma were treated with high-dose chemotherapy and autologous stem cell transplantation. They underwent placement of a central venous port via the subclavian vein for delivery of chemotherapy and reinfusion of stem cells. All patients were followed prospectively for device-related and overall complications, comprising a total of 18,213 days in situ (median: 267 days, range: 90-480). One patient experienced a pneumothorax (1.4%) spontaneously resolved, as an acute toxicity. Two patients (2.8%, 0.1 episodes/1000 days of use) were forced to have the port removed due to infection, caused by Streptococcus mitis in one case, while the causative agent was not identified by laboratory tests in the second. The other 66 patients completed the therapeutic programme, including peripheral stem cell reinfusions and supportive care, such as i.v. antibiotics, antiemetics or fluid administration and blood sample collection, without additional complications. In conclusion, the use of totally implantable central venous access ports has resulted in good long-term access to central veins, in spite of the severe neutropenia and increased septic risk of this category of oncology patients.

Adult↗

Dental health and viridans streptococcal bacteremia in allogeneic hematopoietic stem cell transplant recipients.

Viridans streptococci were the most common cause of bacteremia in 61 consecutive myeloablative allogeneic hematopoietic stem cell transplant (HSCT) recipients, occurring in 19 of 31 bacteremic patients (61%) during the period of post-transplant neutropenia. Seven of the 19 had more than one viridans streptococcus in the same blood culture. Twenty isolates from 15 patients were Streptococcus mitis. Most viridans streptococci were resistant to norfloxacin, used routinely for prophylaxis. Comparison of the 19 patients with viridans streptococcal bacteremia with a contemporaneous group of 23 allogeneic HSCT recipients with fever and neutropenia but no identified focus of infection found that patients with viridans streptococcal bacteremia were more likely to have severe intraoral pathology while neutropenic (26% vs 0%) and slightly shorter interval between the last dental procedure and the onset of neutropenia (11 vs 14 days). Poor underlying dental health and the use of norfloxacin thus appear to predispose to viridans streptococcal bacteremia.

Adult↗

In vitro streptococcal adherence on prosthetic and implant materials. Interactions with physicochemical surface properties.

The aim of this study was to evaluate streptococcal adherence to eight currently used prosthetic and implant materials, and enamel samples, after a salivary coating and to investigate the influence of substrata surface free energy (SFE) and its polar and non-polar components, as well as bacterial surface characteristics, on bacterial adherence. Our results indicate a moderate hydrophobic character of saliva-coated surfaces and a pronounced basic character of the polar component of SFE values, except for one substrata. The lowest colonization was observed with enamel samples and the lowest values of adherent bacteria on the different substrata were observed with the hydrophilic bacterial strain. Both the nature of the substrata and the nature of the bacterial strains could have an effect on the extent of bacterial adhesion. When the interrelationship between the number of adherent bacteria and the surface properties of bacteria and substrata were analysed, bacterial adherence correlated with the non-polar component of substrata SFE (r = 0.8, P = 0.02) and with the adhesion to the solvents (r = 0.8, P < 0.0001). These results are consistent with the thermodynamic theory and underline the importance of acid-base characteristics of the cell surface when one is studying bacterial adherence on dental casting alloys and implant materials.

Bacterial Adhesion↗

Low molecular weight heparin for neonatal thrombosis.

The clinical course of a term neonate (birthweight 3.14 kg) who developed thrombosis of the left common and internal iliac veins on day 21 following recovery from Streptococcus mitis septicemia, with shock diagnosed on day 13, is reported. Subcutaneous low molecular weight heparin (LMWH) was commenced (1.5 mg/kg 12 hourly for 10 days) after 13 h of standard heparin infusion, due to difficulties in securing a peripheral venous access. The inflammation of the left leg was completely resolved by day 5 of LMWH therapy. Prothrombin time, activated prothrombin time and fibrinogen levels were within normal limits during LMWH therapy. Treatment-related side effects, such as thrombocytopenia and bleeding tendency were not noted. Doppler studies 6 weeks after discharge home on day 33 revealed complete resolution of the thrombus. Apart from septicaemia and shock, the presence of an indwelling central venous catheter and a history of untreated maternal diabetes were additional risk factors for thrombosis. Because it is as effective as standard heparin, LMWH may be a therapeutic option for thrombosis in high-risk neonates, particularly given its ease of administration by the subcutaneous route, predictable pharmacokinetics and reduced incidence of adverse effects such as bleeding complications.

Anticoagulants↗

Empirical therapy of febrile neutropenic patients with mucositis: challenge of risk-based therapy.

Nowadays Gram-positive cocci, especially oral viridans streptococci (OVS) and coagulase-negative staphylococci (CoNS), are the most common bloodstream isolates in febrile neutropenic patients. Although in general these cocci are quite indolent, Streptococcus mitis is associated with serious complications such as sepsis and/or adult respiratory distress syndrome. Neutropenia is the most significant predisposing factor but the impact of mucositis, i.e. damage to the mucosal barrier of mouth and intestines (mucosal barrier injury, MBI), is very much greatly underestimated. Oral mucositis is a strong predictor of OVS bacteremia and simultaneously CoNS bacteremia is clearly associated with mucositis. Treatment with especially high dose cytarabine, cyclophosphamide and idarubicin, when given to allogeneic hematopoietic stem cell transplant recipients, predictably results in mucositis. Hence, the occurrence of mucositis should have implications for complementing empirical therapy with specific drugs such as glycopeptides, because risk patients can be selected based upon the chemotherapeutic therapy administered. An algorithm is presented for dealing with patients at high risk of mucositis and bacteremia due to Gram-positive cocci.

Anti-Bacterial Agents↗

Evaluation of swirling, pH, and glucose tests for the detection of bacterial contamination in platelet concentrates.

BACKGROUND: Although infrequent, episodes of transfusion-associated bacterial sepsis may lead to serious outcomes or death and therefore are of concern. This study evaluates the sensitivity of three surrogate tests for the presence of bacteria in platelet concentrates: cessation of swirling, low extracellular pH, and low plasma glucose levels. STUDY DESIGN AND METHODS: Day 0 platelet concentrates were inoculated with low levels of one of seven bacterial strains and stored with agitation at 20 to 24 degrees C for up to 5 days. In the morning and afternoon of each day of storage, bacterial levels were ascertained by quantitative plate culture, and platelet concentrates were tested for platelet pH, plasma glucose, and swirling. Quantitative and semiquantitative dipstick techniques were used to determine pH and glucose levels. RESULTS: Platelet concentrates had attained stationary phase growth of Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Enterobacter cloacae, Streptococcus mitis, or Staphylococcus epidermidis (> or = 10(7) -10(8) colony-forming units [CFU]/mL) before either the swirling or dipstick methods suggested the presence of bacteria. The sensitivity of swirling and glucose tests for detecting bacterial contamination in platelet concentrates was generally comparable. Although the sensitivity of the pH test was generally similar to that of swirling and glucose tests for most bacteria, platelet concentrates contaminated with E. cloacae had normal pH despite the presence of high levels of bacteria (> or = 10(7)-10(8) CFU/mL). CONCLUSION: The sensitivity in detection of bacteria in platelet concentrates by the swirling technique or by measuring extracellular pH or plasma glucose is less than the sensitivity reported for microscopy with Gram stain (10(5)-10(6) CFU/mL), fluorescence microscopy with acridine orange stain (10(4)-10(5) CFU/mL), chemiluminescence detection of ribosomal RNA (10(3)-10(4) CFU/mL), and automated bacterial culture (1 CFU/sample volume).

Bacteremia↗

[Infectious thyroiditis as initial manifestation of embolizing endocarditis of the aortic valve].

HISTORY AND CLINICAL FINDINGS: A 47-year-old patient was admitted to hospital with fever (39.2 degrees C), weight loss and sore throat. The right thyroid area was painful on palpation. INVESTIGATIONS: The erythrocyte sedimentation rate was 56/86 mm, white blood cell count 10,600/l, with shift to the left and toxic granulations. Blood culture grew Streptococcus mitis; the echocardiogram showed vegetations on the aortic valve. Therefore aortic valve endocatidits was suspected. Ultrasound examination of the thyroid gland showed an echo poor area with an enlarged thyroid artery; thyroid cytodiagnosis was unremarkable. TREATMENT: The fever quickly subsided on administration of penicillin G (7.5 mill I.U. three times daily) and tobramycin (80 mg three times daily) for two weeks, followed by penicillin G in the same dosage for four more weeks. Vancomycin was then given for two weeks (1 g twice daily intravenously). The aortic valve vegetations were no longer seen three weeks after onset of treatment. Two months after discharge the thyroid and heart were normal on ultrasound examination. CONCLUSION: Bacterial thyroiditis was caused by embolisation to the thyroid artery from vegetations on the aortic valve in aortic valve endocarditis, probably due to carious teeth.

Anti-Bacterial Agents↗

[Infection caused by viridans streptococci in children with malignant hematologic diseases].

This is a review of the symptoms and signs of children with malignant diseases and septicemia due to viridans streptococci, treated during a 6-year-period (1990-1995) in the Departments of Pediatrics or Pediatric Surgery, University of Leipzig. All 11 children suffered from leukemia. Streptococcus mitis was the most frequently isolated streptococcal species. All patients had fever and malaise, in most cases we could find inflammatory signs of the respiratory tract. In two children we saw a severe course of the disease, one child had symptoms and signs of ARDS, the other died on septicemic shock. All 11 patients had neutropenia and a central venous line, 10 of them were treated by cytarabine before the streptococcal infection was diagnosed. Like others we could note during the last years an increase of systemic infections due to viridans streptococci in neutropenic patients with malignant diseases. Possibly there is an association between streptococcal infection and cytarabine therapy. The empiric antibiotic therapy in neutropenic patients with malignant diseases should cover also streptococcal infections.

Adolescent↗