PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “STAPHYLOCOCCUS INFECTIONS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources

Active screening in high-risk units is an effective and cost-avoidant method to reduce the rate of methicillin-resistant Staphylococcus aureus infection in the hospital.

OBJECTIVE: To evaluate the impact of active screening for methicillin-resistant Staphylococcus aureus (MRSA) on MRSA infection rates and cost avoidance in units where the risk of MRSA transmission is high. METHODS: During a 15-month period, all patients admitted to our adult medical and surgical intensive care units (ICUs) were screened for MRSA nasal carriage on admission and weekly thereafter. The overall rates of all MRSA infections and of nosocomial MRSA infection in the 2 adult ICUs and the general wards were compared with rates during the 15-month period prior to the start of routine screening. The percentage of patients colonized or infected with MRSA on admission and the cost avoidance of the surveillance program were also assessed. RESULTS: The overall rate of MRSA infections for all 3 areas combined decreased from 6.1 infections per 1,000 census-days in the preintervention period to 4.1 infections per 1,000 census-days in the postintervention period (P = .01). The decrease remained statistically significant when only nosocomial MRSA infections were examined (4.5 vs 2.8 infections per 1,000 census-days; P < .01), despite a corresponding increase during the postintervention period in the percentage of patients with onset of MRSA infection in the first 72 hours after admission to the general wards (46% to 81%; P < .005). A total of 3.7% of ICU patients were colonized or infected with MRSA on admission; MRSA would not have been detected in 91% of these patients if screening had not been performed. At a cost of Dollars 3,475/month for the program, we averted a mean of 2.5 MRSA infections/month for the ICUs combined, avoiding Dollars 19,714/month in excess cost in the ICUs. CONCLUSIONS: Even in a setting of increasing community-associated MRSA, active MRSA screening as part of a multi-factorial intervention targeted to high-risk units may be an effective and cost-avoidant strategy for achieving a sustained decrease of MRSA infections throughout the hospital.

Adult↗

Recurring methicillin-resistant Staphylococcus aureus infections in a football team.

An outbreak of community-associated methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI) occurred in a college football team from August to September 2003. Eleven case-players were identified, and boils were the most common sign. Linemen had the highest attack rate (18%). Among 99 (93% of team) players with cultured specimens, 8 (8%) had positive MRSA nasal cultures. All available case-players' MRSA isolates characterized had the community-associated pulsed-field type USA300. A case-control study found that sharing bars of soap and having preexisting cuts or abrasions were associated with infection. A carrier-control study found that having a locker near a teammate with an SSTI, sharing towels, and living on campus were associated with nasal carriage. Successful outbreak control measures included daily hexachlorophene showers and hygiene education.

Adolescent↗

Nationwide investigation in Japan on the efficacy of arbekacin in methicillin-resistant Staphylococcus aureus infections.

A clinical investigation of methicillin-resistant Staphylococcus aureus (MRSA) infections to study the efficacy of arbekacin (ABK) was carried out by the MRSA Forum composed of 18 groups from 115 institutions in Japan. 348 patients (237 male, 111 female) were evaluated. All had infectious diseases clearly related to MRSA. 74 patients were treated with ABK alone and 274 with ABK in combination with other compounds. Most of them (94.6%/96.4%) had primary disease and suffered from pneumonia (38/175), sepsis (6/35) and other infections (30/64). Pure infection by MRSA was noted in 41/159 and polymicrobial infection with MRSA in 33/115. 53.6%/56.4% of MRSA was eradicated; bacteriological clinical efficacy was 75.6%/67.9% in pure infection and 63.6%/71.3% in polymicrobial infection. Clinical effect was obtained within three days in 70.3%/69.3% of total cases, 60.5%/72.0% in pneumonia and 90.0%/80.8% in the patients pretreated with other drugs, respectively. Efficacy ratio was shown to be 78.6%/71.4% in 30 min and 63.2%/66.4% in 60 min. Adverse effects were seen in 4.76%/5.70%, including renal function disorder (2/11), but no case was serious. Abnormal laboratory findings were noted in 15.4% of cases. ABK is effective against MRSA infection. Concurrent treatment with ABK and other drugs is effective in refractory infection.

Aged↗

Incidence of and risk factors for clinically significant methicillin-resistant Staphylococcus aureus infection in a cohort of HIV-infected adults.

OBJECTIVES: Outbreaks of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) have been noted in multiple sites in the United States. This study's purpose was to estimate trends in the incidence of and risk factors for clinically significant MRSA (CS-MRSA) infection in a cohort of HIV-infected adults. DESIGN: A retrospective clinic-based cohort (January 1, 2000-December 31, 2003) study. METHODS: We ascertained all initial episodes of CS-MRSA and categorized them by primary site. Incidence rates were estimated by half year. Risk factors for CA-MRSA infection were identified using Cox modeling. RESULTS: Of 126 potential events, 94 were CS. Their primary sources were 83% skin or soft tissue, 10% blood, 6% respiratory, and 1.0% other sites. Among these, 60% were CA and 40% were nosocomial. Of antibiotics tested, only cotrimoxazole resistance was associated with nosocomial acquisition. The 3455 patients contributed 7003 person-years at risk. The incidence of CS-MRSA infection increased 6.2-fold from the first to the last half year. In multivariate analysis, independent predictors of CA-MRSA infection included HIV transmission by men who have sex with men or by injection drug use, CD4 count <50 cells/muL, log10 HIV plasma viral load, and absence of cotrimoxazole prophylaxis. CONCLUSIONS: The incidence of initial CS-MRSA events increased more than 6-fold in a 4-year period. The associations between CA-MRSA infection and HIV severity indicators merit examination in other cohorts.

Adult↗

Use of long-acting tetracyclines for methicillin-resistant Staphylococcus aureus infections: case series and review of the literature.

BACKGROUND: Few data exist on the efficacy of the long-acting tetracyclines doxycycline and minocycline against methicillin-resistant Staphylococcus aureus (MRSA) infection. METHODS: The medical records of 24 patients with serious tetracycline-susceptible MRSA infections who were treated with doxycycline or minocycline were reviewed. A review of the literature on the use of these antibiotics for treatment of both methicillin-susceptible and methicillin-resistant S. aureus infection was also performed. RESULTS: Complicated skin and skin-structure infections were most common (67%). Clinical cure was achieved in 20 (83%) of 24 patients in our case series. Both drugs were well-tolerated. The review of the literature on a total of 85 patients with S. aureus infection revealed similar results. CONCLUSIONS: Long-acting tetracyclines may be a reasonable treatment alternative for patients with certain types of MRSA infection.

Adult↗

Monitoring bioluminescent Staphylococcus aureus infections in living mice using a novel luxABCDE construct.

Strains of Staphylococcus aureus were transformed with plasmid DNA containing a Photorhabdus luminescens lux operon (luxABCDE) that was genetically modified to be functional in both gram-positive and gram-negative bacteria. S. aureus cells containing this novel lux construct, downstream of an appropriate promoter sequence, are highly bioluminescent, allowing the detection of fewer than 100 CFU in vitro (direct detection of exponentially dividing cells in liquid culture). Furthermore, these bacteria produce light stably at 37 degrees C and do not require exogenous aldehyde substrate, thus allowing S. aureus infections in living animals to be monitored by bioluminescence. Two strains of S. aureus 8325-4 that produce high levels of constitutive bioluminescence were injected into the thigh muscles of mice, and the animals were then either treated with the antibiotic amoxicillin or left untreated. Bioluminescence from bacteria present in the thighs of the mice was monitored in vivo over a period of 24 h. The effectiveness of the antibiotic in the treated animals could be measured by a decrease in the light signal. At 8 h, the infection in both groups of treated animals had begun to clear, as judged by a decrease in bioluminescence, and by 24 h no light signal could be detected. In contrast, both groups of untreated mice had strong bioluminescent signals at 24 h. Quantification of CFU from bacteria extracted from the thigh muscles of the mice correlated well with the bioluminescence data. This paper shows for the first time that bioluminescence offers a method for monitoring S. aureus infections in vivo that is sensitive and noninvasive and requires fewer animals than conventional methodologies.

Amoxicillin↗

Fatal influenza A infection with Staphylococcus aureus superinfection in a 49-year-old woman presenting as sudden death.

A fatal case of influenza A infection with Staphylococcus aureus superinfection in a previously healthy 49-year-old woman presenting as sudden, unexpected death is reported. Autopsy revealed severe necrotizing tracheobronchitis and hemorrhagic pneumonia. Microscopic examination of the trachea and bronchi showed mucosal necrosis and a dense lympho-monocytic infiltration of all layers. The lungs showed focal hemorrhagic pneumonia. No pathological changes were detectable in the myocardium. Influenza A virus was detected in bronchi and lung samples obtained during autopsy by the polymerase chain reaction (PCR) and bacterial superinfection with Staphylococcus aureus was shown by culturing from tracheal, bronchial and pulmonary swabs obtained during autopsy. PCR assays for the detection of Panton-Valentine leukocidin performed from all samples were negative. This case demonstrates the need for an interdisciplinary approach towards an organism-specific diagnosis of potentially infection-related deaths undergoing a medico-legal autopsy. With improved diagnostic possibilities such as PCR and DNA sequencing, forensic pathologists can, in close association with the field of microbiology, make a significant contribution to the detection of highly infectious agents which must be notified to the authorities. This will increase particularly the knowledge about the influence of these agents on sudden, unexpected deaths in outpatients.

Death, Sudden↗

99mTc-Labeled UBI 29-41 peptide for monitoring the efficacy of antibacterial agents in mice infected with Staphylococcus aureus.

UNLABELLED: Based on our earlier observation that (99m)Tc-UBI 29-41, a radiolabeled peptide derived from ubiquicidin (UBI), discriminates between infections and sterile inflammatory processes, we considered the possibility that this tracer could be used for monitoring the efficacy of antibacterial agents in animals infected with Staphylococcus aureus. METHODS: We injected (99m)Tc-UBI 29-41 into S. aureus-infected mice after treatment with various doses of cloxacillin or erythromycin. At intervals thereafter, accumulation of the radiolabeled peptide at the site of infection was assessed by scintigraphy. When S. aureus was antibiotic resistant, we evaluated the efficacy of hLF 1-11, an antimicrobial peptide derived from human lactoferrin (hLF), in rats using (99m)Tc-UBI 29-41 and scintigraphy. RESULTS: Decreasing amounts of radiolabeled peptide at the site of the S. aureus infection in animals correlated (r(2) > 0.81; P < 0.001) with increasing doses of cloxacillin in animals. An effective dose of erythromycin resulted in reduced (P = 0.023) accumulation of the radiolabeled peptide at the site of S. aureus infection in mice. In addition, we noted decreasing amounts of (99m)Tc-UBI 29-41 at the site of infection after administration of increasing doses of hLF 1-11 peptide in rats infected with antibiotic-resistant S. aureus. Furthermore, the number of viable bacteria decreased with increasing doses of cloxacillin or hLF 1-11 peptide, and a good correlation (r(2) > 0.80; P < 0.001) between the accumulation of (99m)Tc-UBI 29-41 and the number of viable (antibiotic-resistant) S. aureus at the site of infection was seen. In an attempt to explain these results, we found that these antibacterial agents do not affect the in vitro binding of (99m)Tc-UBI 29-41 to bacteria. Furthermore, this radiolabeled peptide bound to free bacteria and to cell-adherent but not phagocytized S. aureus, suggesting that at sites of infection mainly extracellular bacteria are targeted by (99m)Tc-UBI 29-41. CONCLUSION: (99m)Tc-UBI 29-41 allows the monitoring of the efficacy of antibacterial agents in mice and rats with S. aureus infections.

Animals↗

An integrated critique of the efficacy of topical mupirocin in preventing catheter-related Staphylococcus aureus infections in peritoneal dialysis clients.

Several epidemiological studies indicate that, for two reasons, Staphylococcus aureus (SA) nasal carriage is a risk factor for developing SA infections in peritoneal dialysis (PD) clients. First, nasal carriage is prevalent in these clients due to the nature of their disease. Second, there is a significant relationship between nasal and hand carriage of the SA organism. Because PD clients require frequent catheter handling to receive therapy, they are at risk for catheter contamination. Two prospective randomized control trials and two prospective cohort trials with historical controls were selected for review. Emphasis was placed on the design feature of a comparison or control group in order to find empirical support for the efficacy of topical mupirocin (Bactroban) as an infection control measure. The four studies selected also used two methods of application, the first application was to the nares and the second was to the catheter exit site. The result of the analysis revealed a weak support for the prophylactic role of topical mupirocin in preventing SA exit-site infections (ESI) in PD clients. Well-controlled prospective, randomized studies with sufficiently large sample sizes to produce statistically and clinically significant results for the prophylactic role of mupirocin are lacking. In light of the analysis, the advocacy of several practice implications involving client education and timely follow-up, staff training, and client comfort are warranted.

Administration, Topical↗

Role of linezolid in the treatment of complicated skin and soft tissue infections.

Staphylococcus aureus is the most common cause of complicated skin and soft tissue infections (cSSTIs). Antibiotic choices for these infections continue to evolve. History has seen penicillin progress to antistaphylococcal penicillins and cephalosporins, but these drugs are now giving way to drugs that are effective against methicillin-resistant S. aureus (MRSA). While vancomycin has been the gold standard to treat MRSA infections, newer therapeutic options have been developed over the last 5 years. These include quinupristin-dalfopristin, daptomycin, tigecycline and linezolid, which is the focus for this review. Linezolid is efficacious in the treatment of cSSTIs (including diabetic foot infections) caused by Gram-positive organisms (including MRSA), with a well-defined safety profile and straightforward dosing. It is also approved for nosocomial pneumonia, community-acquired pneumonia and uncomplicated skin and skin structure infections. Linezolid has an oral and parenteral formulation, which are equivalent. The oral formulation has the potential to offer economic benefits as compared with other therapies. Currently, there are only a few new antibiotics in development with MRSA activity. The proper use of all antibiotics, including these newer agents, is increasingly important if we are to slow the evolution of microbial resistance.

Acetamides↗

Cellular inflammatory response to persistent localized Staphylococcus aureus infection: phenotypical and functional characterization of polymorphonuclear neutrophils (PMN).

Persistent, localized Staphylococcus aureus infections, refractory to antibiotic treatment, can result in massive tissue destruction and surgical intervention is often the only therapeutic option. In that context, we investigated patients with S. aureus-induced infection at various sites, apparent as either olecranon bursitis, empyema of the knee joint or soft tissue abscess formation. As expected, a prominent leucocyte infiltrate was found, consisting predominantly of polymorphonuclear neutrophils (PMN) (up to 75%) and to a lesser extent of T lymphocytes and natural killer (NK) cells. In line with their bactericidal capacity, PMN expressed the high-affinity receptor for IgG, CD64 and the lipopolysaccharide (LPS) receptor CD14; moreover, the oxygen radical production in response to the bacterial peptide f-MLP was enhanced, while chemotactic activity was greatly reduced. The more intriguing finding, however, was that a portion of PMN had acquired major histocompatibility complex (MHC) class II antigens and CD83, indicative of a transdifferentiation of PMN to cells with dendritic-like characteristics. Of note is that a similar transdifferentiation can be induced in PMN in vitro, e.g. by gamma interferon or by tumour necrosis factor alpha. Co-cultivation of transdifferentiated PMN with autologous T lymphocytes resulted in prominent T cell proliferation, provided that S. aureus enterotoxin A was added. Taken together, persistent S. aureus infection induces PMN to acquire characteristics of dendritic cells, which in turn might promote the local immune response.

Aged↗

Population-based study of the epidemiology of and the risk factors for invasive Staphylococcus aureus infections.

A population-based active-surveillance study of the Calgary Health Region (population, 929,656) was conducted from May 1999 to April 2000, to define the epidemiology of invasive Staphylococcus aureus (ISA) infections. The annual incidence was 28.4 cases/100,000 population; 46% were classified as nosocomial. Infection was most common in people at the extremes of the age spectrum and in males. Several conditions were associated with acquisition of ISA infection, and the highest risk was observed in persons undergoing hemodialysis or peritoneal dialysis and in persons infected with human immunodeficiency virus. Forty-six patients (19%) died. Significant independent risk factors for mortality included positive blood-culture result, respiratory focus, empirical antibiotic therapy, and older age. A higher systolic blood pressure at presentation was associated with reduced case-fatality rate. ISA infections are common, with several definable groups of patients at increased risk for acquisition and death from these infections. This study provides important data on the burden of ISA disease and identifies risk groups that may potentially benefit from preventive efforts.

Adolescent↗

Onset of Berger disease after Staphylococcus aureus infection: septic arthritis after anterior cruciate ligament reconstruction.

Septic arthritis is rare in patients undergoing knee arthroscopic surgery. If the infection is due to Staphylococcus aureus, patients might experience fever, severe clinical syndromes, and extra-articular manifestations, including vasculitis and glomerulonephritis. We describe a case of onset of immunoglobulin A nephropathy (Berger disease) after S aureus septic arthritis complicating an anterior cruciate ligament surgical reconstruction. The patient had no previous history of renal disease, and renal function returned to normal after resolution of the knee infection. S aureus infection has been associated with several glomerular diseases, but this is the first report of the infection causing immunoglobulin A nephropathy. In addition, this is the first description of Berger disease after arthroscopic treatment, providing evidence that this disease might complicate the clinical course of orthopedic surgery.

Adult↗

Immune cell differentiation in mammary gland tissues and milk of cows chronically infected with Staphylococcus aureus.

This study identifies and compares the distribution of mononuclear cells in the mammary gland tissues and milk of healthy and chronically infected with Staphylococcus aureus cows. Somatic cell counts (SCCs) during the 3 months before the study were > 1 x 10(6) cell/ml in the infected quarters and < 1 x 10(5) cell/ml in the infection-free quarters. Immediately after slaughter, samples from the tissues above the gland cistern and supra-mammary lymph node were collected. No histological differences were found between the supra-mammary lymph nodes of the healthy and infected udders, and both appeared normal. In the milk of the healthy infection-free mammary glands, SCC was < 50,000 cells/ml) while epithelial cells were the predominant type. The percentage of CD18+ was low than 45%, of which over three-quarters were polymorphonuclear (PMN), and less than one- quarter were mononuclear cells. The later comprised CD4+ or CD8+ T-lymphocytes, macrophages (Mo) but not B-cells. In the tissues, there were few CD18+ leukocytes, and most of the cells were T-lymphocytes. The number of B-lymphocytes bearing CD21+ was similar to that of CD8+ and were localized in the connective tissue as clusters of 2-5 cells, mainly in areas with no alveoli, or as single cell having a dendritic like form. The number of Mos was negligible. In the milk of the infected glands, SCC exceeded 700,000 cells/ml, of which > 95% were CD18+ positive. The distribution of the leukocytes had two patterns: one presented (> 80%) of PMN cells and a small number of mononuclear cells; the second had less than 50% PMN and many mononuclear cells. The CD8+ cells in these infected sections were observed throughout the mammary epithelial cells (MEc) around the alveoli and in the alveolar lumen (AL). The numbers and the location of CD21+ B-lymphocytes were similar to those in the infection-free mammary glands. The number of CD5+ positive cells was lower than T and B- cells combined and were located throughout the mammary epithelial cells, around the alveoli and within the connective tissue. Mo numbers were high in most of those infected quarters, and were localized around the connective tissue and within the AL.

Animals↗

Mycotic aneurysm of common carotid artery induced by Staphylococcus aureus infection after cervical reoperation.

The objective of this study was to define a novel type of mycotic aneurysm of the carotid artery arising after cervical reoperation. We retrospectively analyzed all staphylococcal mycotic aneurysms of the common carotid artery. These aneurysms had developed after reoperative thyroid or parathyroid surgery, including resection of the central lymph node compartment and cervical reexploration. Mycotic aneurysms were found in three patients, with an incidence of 0.77% (2/261) and 0.62% (1/161) for thyroid and parathyroid reoperations, respectively. Postoperatively, a lymphatic fistula and cervical hematoma emerged in all patients, as did cervical wound infections on days 3, 4, and 6. Deep wound infections were noted on surgical revision. Cultures grew exclusively Staphylococcus aureus, which was resistant to methicillin (MRSA) in one patient. Mycotic aneurysms were identified 1 week after cervical reoperation. One aneurysm was discovered incidentally on planned lavage. The other two aneurysms presented as severe arterial hemorrhages, resulting in exsanguination in one patient. The other two patients had their aneurysms replaced by saphenous venous autografts. There seems to be accelerated arterial media destruction with formation of mycotic aneurysms in staphylococcal wound infections after cervical reoperation. It is important to recognize this novel type of mycotic aneurysm, as it must be repaired immediately to anticipate imminent rupture.

Adult↗