Staphylococcal Infections In Patients Research Articles

A Web-Based Dynamic Nomogram to Predict the Risk of Methicillin-Resistant Staphylococcal Infection in Patients with Pneumonia.

The aim of this study was to create a dynamic web-based tool to predict the risks of methicillin-resistant Staphylococcus spp. (MRS) infection in patients with pneumonia. We conducted an observational study of patients with pneumonia at Cho Ray Hospital from March 2021 to March 2023. The Bayesian model averaging method and stepwise selection were applied to identify different sets of independent predictors. The final model was internally validated using the bootstrap method. We used receiver operator characteristic (ROC) curve, calibration, and decision curve analyses to assess the nomogram model's predictive performance. Based on the American Thoracic Society, British Thoracic Society recommendations, and our data, we developed a model with significant risk factors, including tracheostomies or endotracheal tubes, skin infections, pleural effusions, and pneumatoceles, and used 0.3 as the optimal cut-off point. ROC curve analysis indicated an area under the curve of 0.7 (0.63-0.77) in the dataset and 0.71 (0.64-0.78) in 1000 bootstrap samples, with sensitivities of 92.39% and 91.11%, respectively. Calibration analysis demonstrated good agreement between the observed and predicted probability curves. When the threshold is above 0.3, we recommend empiric antibiotic therapy for MRS. The web-based dynamic interface also makes our model easier to use.

Poly (ε-caprolactone)/Poly (lactic acid) fibers produced by rotary jet spinning for skin dressing with antimicrobial activity.

The rotary jet spinning technique permits the production of biomaterials that can be used as devices that come into contact with biological systems (including biological fluids) for diagnostic or surgical applications. These materials are composed of synthetic or natural compounds and allow the incorporation of drugs for therapeutic purposes. Two solutions containing 50% poly(lactic acid) (PLA) and 50% poly(ε-caprolactone) (PCL) diluted in three different solvents were prepared for rotary jet spinning (RJS) process. Vancomycin, an antibiotic indicated for the treatment of severe staphylococcal infections in patients with penicillin allergy, was added in the polymer solutions, to obtain drug-loaded fibrous mats. Morphological surface characterization by scanning electron microscopy revealed heterogeneous pores in the microfibers. Vancomycin loading interfered with the morphology of all samples in terms of fiber size, leading to smaller diameter fibers. Attenuated total reflectance/Fourier transform infrared spectroscopy was used for identification of the samples. The vibrational characteristics of PCL/PLA and vancomycin were consistent with expectations. Vero cell culture assays by the extract dilution and direct contact methods revealed the absence of cytotoxicity, except for the sample prepared with 50% of PCL and of a 9/2 (V/V) vancomycin content, with the growth of confluent and evenly spread cells on the fibrous mats surface. Microbiological analysis, performed on Staphylococcus aureus by the halo inhibition test and by the broth dilution method, showed that the antibacterial activity of vancomycin was maintained by the loading process in the polymer fibers. The results showed that rotary jet spinning produces satisfactory amounts of Vancomycin-loaded fibers, as potential web dressing for wound repair.

THE ROLE OF STAPHYLOCOCCUS AUREUSIN THE CLINICAL DIAGNOSIS OF DIABETIC PATIENTS

Abstract Discovering interactions between the etiology of the infection and diabetic patients’ immune system activity may be essential for the relevant clinical diagnosis. The dynamics of colonization of the nasal vestibule by Staphylococcus aureus and the development of the prevention strategies against infection are different for various populations. Moreover, the colonization of the nasal vestibule might involve both molecular and epidemiological ctorsfa. Researchers have reported that the identification of methicillin-resistant strains S. aureus(MRSA) with similar molecular characteristics allows to assess the ability of the microorganism to spread and the risk of infection in diabetic patients. Knowledge of these characteristics allows to take precautions in patients exposed to S. aureus. S. aureus is an ethiological factors of many severe diseases both in people with weakened immune system and in healthy individuals. Usually, excess weight and obesity contribute to the incidence of diabetes mellitus type 2 (DM2). However, the colonization by S. aureus is a probable risk factor for infection. Among S. aureus virulence factors, superantigens (SAgs) are essential for pathogenicity. The long-term effect of the superantigen toxic shock syndrome toxin-1 (TSST-1) might be glucose intolerance. This toxin also induces systemic inflammation as a result of the increased exotoxin concentration in blood, and, therefore, may be the causative factor of diabetes. Chronic exposure to staphylococcal superantigens may contribute to the development of diabetes, suggesting a need to conduct targeted therapies against S. aureus superantigens. 1. Introduction. 2. Risk factors for infection in patients with diabetes. 2.1. Immunodeficiency. 2.2. Obesity 2.3. Staphylococcal carriage. 3. Staphylococcal infections in patients with diabetes. 3.1. Staphylococcal superantigens. 3.2. Skin and soft tissue infections. 3.3.Diabetic foot syndrome. 3.4. Sepsis. 3.5. Infective endocarditis. 3.6. Acute purulent meningitis. 4. Vaccination. 5. Conclusions

Extranasal Staphylococcus aureus colonization predisposes to bloodstream infections in patients on hemodialysis with noncuffed internal jugular veincatheters.

Staphylococcal infection of endogenous origin is an important cause of morbidity and mortality in patients who receive hemodialysis (HD). The risk of such infections in nasal carriers of the organism is well defined. Extranasal carriage of the organism at extranasal sites may pose similar risks. A total of 70 patients about to undergo internal jugular vein catheterization for HD were enrolled in this prospective observational study. Swab cultures were obtained from anterior nares, posterior pharynx, axillae, toe web spaces, and vascular access sites at baseline and 1 week later. A patient was defined as a persistent carrier when the same organism was grown in both samples. Staphylococcus aureus bloodstream infections were assessed by blood and catheter tip cultures over a 90-day period. The mean age of the patients was 43.71 ± 16.2 years. Persistent S. aureus carriage at anterior nares, throat, axilla, toe web spaces, vascular access site, and all sites was documented in 27.9%, 11.4%, 40%, 32.9%, 4.3%, and 64.2% of patients, respectively. Fifteen patients developed S.aureus infections. Catheter related S. aureus infections (CRI) were more likely in persistent carriers than nonpersistent carriers with odds ratios (95% CI) of 10.2 (2.8-37.1), 8.6 (1.7-42.2), 17.3(3.4-86.0), 3.0 (0.9-9.8), and 1.9 (0.2-22.4) for anterior nares, throat, axilla, toe web spaces, and vascular access site carriers, respectively. The probability of developing CRI in persistent S.aureuscarriers was 55% compared to none in noncarriers at 90 days (P = 0.04). Extranasal S. aureus carriage is as significant a risk factor as nasal carriage for staphylococcal infections in patients on HD through catheters. The study is limited by lack of molecular phenotyping.

Iron-Dependent Synthesis of Hemolysins by Staphylococcus aureus

We studied the effect of Fe(2+) on hemolysin synthesis by Staphylococcus aureus. Hemolytic activity of staphylococci was shown to be iron-dependent. Addition of Fe(2+) to the nutrient medium induced the synthesis of α-hemolysin by staphylococci. Increasing the concentration of Fe(2+) was followed by an increase in hemolytic activity of staphylococci. Inducible synthesis of α-hemolysin probably serves as an important pathogenetic factor in the development of staphylococcal infection in patients with excessive iron accumulation in the body.

Pneumonia due to methicillin-resistant Staphylococcus aureus: clinical features, diagnosis and management

The review highlights the clinical findings and the management of community-acquired, health-care associated and nosocomial pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA). Although previously considered as a purely nosocomial event, community-acquired MRSA pneumonia is underestimated and is spreading worldwide. A retrospective study showed that almost half of patients with nonnosocomial MRSA pneumonia admitted to a large teaching hospital did not present established criteria for healthcare-associated infections. Recent data show that MRSA ventilator-associated pneumonia is associated with significantly higher mortality than ventilator-associated pneumonia caused by methicillin-susceptible Staphylococcus aureus. Therefore, prompt and appropriate therapy is essential. The optimal therapy for MRSA pneumonia has not been fully elucidated. Although vancomycin has been considered the gold standard for the treatment of MRSA infections, clinical failures have also been reported in the presence of in-vitro susceptibility. Linezolid may provide improved outcomes compared with vancomycin in patients with MRSA pneumonia, but validation in a prospective trial is currently lacking. Recently licensed tigecycline and dalbavancin, a drug in phase III trial, look promising. Animal models showed that immunization against a cytolytic toxin secreted by most Staphylococcus aureus strains protects against lethal pneumonia. Rapid recognition of possible staphylococcal infection in patients with severe pneumonia is essential. The treatment of MRSA pneumonia must be prompt and effective in order to allow a fast microbiological clearance and to successfully manage the infection.

Immunity to Microbes: Lessons from Primary Immunodeficiencies

Primary immunodeficiency diseases (PIDs) represent a large and heterogeneous group of more than 120 different entities, most of which have now been genetically characterized (77). Increased susceptibility to infections is the predominant manifestation of almost all forms of PID, particularly in infants and children, demonstrating the paramount importance of the immune system in defense against infection. It has long been known that the nature of an immune defect is related to the etiology of an infection. Prime examples are recurrent respiratory infections with pyogenic bacteria in patients with antibody deficiencies, opportunistic infections with fungi and viruses in infants with SCID (severe combined immunodeficiency), Neisseria meningitidis infections as a hallmark of defects in late-complement components, recurrent staphylococcal infections in patients with neutrophil disorders, and susceptibility to weakly virulent mycobacterial diseases and to Salmonella in patients with deficiencies of the interleukin-12 (IL-12)/IL-23-gamma interferon (IFN-γ) axis. Studies of PID patients have actually contributed to clarification of the anti-infection roles of several mechanisms and components of the immune response, as PIDs offer unique opportunities to link phenotypes to immunological functions and to ascribe various classes of immunity to defenses against different microbes. Thus, studies of agammaglobulinemic patients were crucial in elucidating the role of antibodies in immunity to extracellular bacteria and enteroviruses, as were studies of children with Kostmann's syndrome (congenital severe neutropenia) and chronic granulomatous disease (CGD) in defining the critical role of neutrophils and studies of SCID patients in showing the relevance of T-cell immunity in resistance to intracellular pathogens. More recently, as clinical phenotypes are being mapped to gene defects, respective pathophysiologies can be better understood, often with the help of murine knockout models. Here we offer an observational approach to host/parasite relationships, based on clinical features of PID patients. After an exhaustive review of the main infectious manifestations of PID patients described in large published series as well as in our own series, we propose a novel classification of PIDs according to the degrees of clinical susceptibility to infectious agents observed with PID patients, attempting to link selective susceptibility to specific mechanisms and to established genetic defects. Evidence for a causal association between a particular infection and a given PID is available in some cases, but in others, only a small number of patients have been studied. The data were organized in tables that classify susceptibility to each infection as high (when it is a major manifestation of disease), intermediate (when it appears in some cases but not as a rule), and low (when it is seldom seen). We believe that organizing available information in this manner may also be helpful for the physician, whose identification of a given infection may help determine a putative immunodeficiency.

Isolation of Staphylococcus aureus from the Urinary Tract: Association of Isolation with Symptomatic Urinary Tract Infection and Subsequent Staphylococcal Bacteremia

Staphylococcus aureus is frequently isolated from urine samples obtained from long-term care patients. The significance of staphylococcal bacteriuria is uncertain. We hypothesized that S. aureus is a urinary pathogen and that colonized urine could be a source of future staphylococcal infection. We performed a cohort study of 102 patients at a long-term care Veterans Affairs facility for whom S. aureus had been isolated from clinical urine culture. Patients were observed via urine and nasal cultures that were performed every 2 months. We determined the occurrence of (1) symptomatic urinary tract infection concurrent with isolation of S. aureus (by predetermined criteria), (2) staphylococcal bacteremia concomitant with isolation of S. aureus from urine, and (3) subsequent episodes of staphylococcal infection. Of 102 patients, 82% had undergone recent urinary catheterization. Thirty-three percent of patients had symptomatic urinary tract infection at the time of initial isolation of S. aureus, and 13% were bacteremic. Eight-six percent of the initial urine isolates were methicillin-resistant S. aureus. Seventy-one patients had follow-up culture data; 58% of cultures were positive for S. aureus at > or =2 months (median duration of staphylococcal bacteriuria, 4.3 months). Sixteen patients had subsequent staphylococcal infections, occurring up to 12 months after initial isolation of S. aureus; 8 late-onset infections were bacteremic. In 5 of 8 patients, the late blood isolate was found to have matched the initial urine isolate by pulsed-field gel electrophoresis typing. S. aureus is a cause of urinary tract infection among patients with urinary tract catheterization. The majority of isolates are methicillin-resistant S. aureus. S. aureus bacteriuria can lead to subsequent invasive infection. The efficacy of antistaphylococcal therapy in preventing late-onset staphylococcal infection in patients with persistent staphylococcal bacteriuria should be tested in controlled trials.

Preoperative Intranasal Mupirocin Ointment Significantly Reduces Postoperative Infection with Staphylococcus aureus in Patients Undergoing Upper Gastrointestinal Surgery

Nasal carriage of Staphylococcus aureus including methicillin-resistant S. aureus (MRSA) is associated with an increased risk for postoperative staphylococcal infection. This study was conducted to investigate the effect of preoperative nasal mupirocin treatment on the postoperative infections in patients undergoing upper gastrointestinal surgery. The intervention group consisted of 141 consecutive patients who underwent upper gastrointestinal surgery between March 1, 1997, and February 28, 1998. The patients in the intervention group were treated with intranasal mupirocin three times a day for 3 consecutive days before surgery. The incidence of postoperative staphylococcal infections in the intervention group was then compared with that of the historical control group. The control group consisted of 128 consecutive patients who underwent upper gastrointestinal surgery without mupirocin treatment between January 1, 1996 and December 31, 1996. The postoperative staphylococcal infection rate in the control group (11.7%) was significantly higher (P < 0.001) than in the intervention group (0.71%). The postoperative MRSA infection rate was significantly reduced by the intervention (control group 7.0% and intervention group 0%; P < 0.01). These results suggest that preoperative nasal eradication of S. aureus with mupirocin thus appears to be an effective measure to prevent postoperative staphylococcal infection in patients undergoing upper gastrointestinal surgery.

Fusidic acid in other infections

Fusidic acid, both systemic and topical, has been used for a wide variety of less common infections. Efficacy for oral fusidic acid has been demonstrated in the treatment of Clostridium difficile colitis and in staphylococcal infections in patients with cystic fibrosis. Topical fusidic acid gel is also effective in bacterial conjunctivitis and other minor external eye infections, and may be effective in reducing bacterial flora in the conjunctival sac prior to eye surgery. Studies suggest a potential role for fusidic acid in neurosurgical prophylaxis, as adjunctive therapy in bacterial endophthalmitis and Legionella pneumonia, and in leprosy. Topical fusidic acid has no effect in the treatment of chlamydial conjunctivitis or the prevention of staphylococcal infections in patients on continuous ambulatory peritoneal dialysis.

Toxic Shock Syndrome and Staphylococcal Infection--Reply

To the Editor-Ferguson and Todd [1] reported three patients with toxic shock syndrome alleged to be caused by a focus of infection in the paranasal sinuses. It is appropriate to search for a focus of staphylococcal infection in patients with toxic shock syndrome; however, staphylococci are an uncommon cause of acute sinusitis in children and adults [2, 3]. To establish the precise cause of maxillary sinusitis, a sinus aspirate must be obtained. The preferred approach to the maxillary sinus is passage of a trocar beneath the inferior turbinate across the lateral nasal wall. It is essential to sterilize the nasal mucosa before maxillary sinus aspiration, as the nasal vestibule is a heavily colonized mucous membrane and staphylococci are frequent colonizers [4, 5]. Further, to be certain that bacteria recovered by sinus aspiration actually represent sinus infection and not contamination from the nose, quantitation of the bacterial isolate (or at least a report of Gram's stain results) is encouraged. Infection is defined as the recovery of a bacterial species in a density of ^lO4 cfu/ml [2]. Most maxillary sinus infections show bacteria in a density much greater than 104 cfu/ml. The method of and preparation for sinus aspiration was not described by Ferguson and Todd [1].

Staphylococcus aureus bacteremia and recurrent staphylococcal infection in patients with acquired immunodeficiency syndrome and aids-related complex

An increased incidence of Staphylococcus aureus bacteremia has recently been described in patients with the acquired immunodeficiency syndrome (AIDS). However, other risk factors for community-acquired S. aureus bacteremia (including intravenous drug abuse and lymphedema) were present in nearly all these AIDS-related cases of S. aureus infection. Our purpose was to review cases of S. aureus bacteremia that occurred in patients with AIDS or AIDS-related complex (ARC) who did not have a recent history of intravenous drug use, lymphatic obstruction, or neutropenia. Patients at San Francisco General Hospital between October 1984 and October 1987 with blood culture results positive for S. aureus were identified. A review of this group revealed 22 cases of S. aureus bacteremia that occurred in 18 patients with an underlying diagnosis of AIDS or ARC, none of whom had a recent history of intravenous drug use, lymphedema secondary to Kaposi's sarcoma, or neutropenia. An intravenous catheter was the single most important risk factor for S. aureus bacteremia and was identified as the source for bacteremia in 16 (73 percent) of the 22 episodes. Based on 1986 outpatient clinic records, we calculated an incidence of S. aureus bacteremia occurring in non-intravenous-drug-using male AIDS or ARC patients, 18 to 44 years old, that was 5.4 episodes/1,000 patients. Although the mean duration of appropriate antibiotic therapy was 18 days, late metastatic complications of S. aureus bacteremia occurred in six (35 percent) of 17 AIDS/ARC patients who survived initial antibiotic therapy. Non-intravenous-drug-using AIDS and ARC patients (especially those with indwelling venous catheters) appear to be at high risk for S. aureus bacteremia, with a higher late metastatic complication rate than that reported for recent historical control subjects.

Staphylococcus aureus bacteremia and recurrent staphylococcal infection in patients with acquired immunodeficiency syndrome and AIDS-related complex1

<h3>Purpose</h3> An increased incidence of <i>Staphylococcus aureus</i> bacteremia has recently been described in patients with the acquired immunodeficiency syndrome (AIDS). However, other risk factors for community-acquired <i>S. aureus</i> bacteremia (including intravenous drug abuse and lymphedema) were present in nearly all these AIDS-related cases of <i>S. aureus</i> infection. Our purpose was to review cases of <i>S. aureus</i> bacteremia that occurred in patients with AIDS or AIDS-related complex (ARC) who did not have a recent history of intravenous drug use, lymphatic obstruction, or neutropenia. <h3>Patients and methods</h3> Patients at San Francisco General Hospital between October 1984 and October 1987 with blood culture results positive for <i>S. aureus</i> were identified. A review of this group revealed 22 cases of <i>S. aureus</i> bacteremia that occurred in 18 patients with an underlying diagnosis of AIDS or ARC, none of whom had a recent history of intravenous drug use, lymphedema secondary to Kaposi's sarcoma, or neutropenia. <h3>Results</h3> An intravenous catheter was the single most important risk factor for <i>S. aureus</i> bacteremia and was identified as the source for bacteremia in 16 (73 percent) of the 22 episodes. Based on 1986 outpatient clinic records, we calculated an incidence of <i>S. aureus</i> bacteremia occurring in nonintravenous-drug-using male AIDS or ARC patients, 18 to 44 years old, that was 5.4 episodes/1,000 patients. Although the mean duration of appropriate antibiotic therapy was 18 days, late metastatic complications of <i>S. aureus</i> bacteremia occurred in six (35 percent) of 17 AIDS/ARC patients who survived initial antibiotic therapy. <h3>Conclusion</h3> Non-intravenous-drug-using AIDS and ARC patients (especially those with indwelling venous catheters) appear to be at high risk for <i>S. aureus</i> bacteremia, with a higher late metastatic complication rate than that reported for recent historical control subjects.

Antibodies to staphylococcal teichoic acid and alpha toxin in patients with cystic fibrosis.

Enzyme-linked immunosorbent assay (ELISA) was used for IgG antibody determination to teichoic acid and alpha-toxin from Staphylococcus aureus in 65 patients with cystic fibrosis (CF). In patients chronically colonized with S. aureus, elevated titres to teichoic acid were found in 13/35 (37%) patients, to alpha-toxin in 12/35 (34%) and to either antigen in 18/35 (51%). Patients with elevated titres to teichoic acid had a significantly lower X-ray score than patients with normal titres. The highest titres against both teichoic acid and alpha-toxin were seen in patients not receiving optimal treatment. These findings suggest that staphylococci contribute to the tissue damage in CF and that the determination of antibodies especially to staphylococcal teichoic acid might be of value in the diagnosis and management of staphylococcal infections in patients with CF.

In-vivo effects of clindamycin on neutrophil function.

Neutrophil functions were evaluated in 13 normal subjects who had received 300 mg of clindamycin orally four times each day for two days. The mean serum concentration of clindamycin was 1.6 mg/l. Intracellular killing of a clindamycin-resistant strain of Staphylococcus aureus increased from 38% to 45%, P less than 0.005, during clindamycin therapy. In contrast, clindamycin therapy did not significantly alter chemotaxis, phagocytosis, chemiluminescence of neutrophils, or the ability of serum to generate chemotactic factor and opsonize particles of yeast. The potentially synergistic relationship between clindamycin and neutrophils may prove to be valuable for the treatment of staphylococcal infections in patients with defects in oxygen-dependent mechanism of neutrophil-mediated bacterial killing such as in chronic granulomatous disease.

Dermatology: An Annotated Bibliography of Recent Literature

Dermatology: An Annotated Bibliography of Recent Literature

Vancomycin Revisited

Vancomycin, virtually discarded after development of antistaphylococcal penicillins, has recently been receiving renewed attention. There are several clinical situations in which it appears to offer advantages over other available antimicrobial agents: infections due to methicillin-resistant staphylococci; bacterial endocarditis in patients allergic to penicillin; staphylococcal enterocolitis; staphylococcal infection in patients undergoing hemodialysis; infections caused by penicillin-resistant diphtheroids; and prophylaxis of bacterial endocarditis in patients with prosthetic valves or penicillin allergy. Its penetration into the cerebrospinal fluid suggests that vancomycin may be useful in treating certain infections of the central nervous system. Although its ototoxic and nephrotoxic potential cannot be ignored, these problems can be minimized by keeping the serum concentration at the proper level.

Staphylococcal Infections in Patients With Atopic Dermatitis

Cutaneous staphylococcal infections appear to be relatively infrequent in atopic dermatitis even though patients have broken skin heavily colonized with staphylococcal organsism. We found superficial staphylococcal pustules on the skin of 22 patients with atopic dermatitis. Such lesions were more commonly found with severe exacerbations of atopic dermatitis. They appeared on unbroken skin independent of hair follicles and were associated with considerable pruritus. Such lesions were rapidly removed by excoriation and frequently were overlooked by patients and physicians. Most lesions appeared when polymorphonuclear leukocyte chemotaxis was depressed. Ineffective chemotaxis combined with high-colonization density and inadequate stratum corneum barrier during exacerbations of atopic dermatitis may lead to mild staphylococcal infections. These infections appear to have no systemic effects but possibly the considerable associated pruritus could worsen the atopic dermatitis. Occasional patients may require intermittent or continuous antibiotic therapy.

Staphylococcal infections in patients with atopic dermatitis

• Cutaneous staphylococcal infections appear to be relatively infrequent in atopic dermatitis even though patients have broken skin heavily colonized with staphylococcal organisms. We found superficial staphylococcal pustules on the skin of 22 patients with atopic dermatitis. Such lesions were more commonly found with severe exacerbations of atopic dermatitis. They appeared on unbroken skin independent of hair follicles and were associated with considerable pruritis. Such lesions were rapidly removed by excoriation and frequently were overlooked by patients and physicians. Most lesions appeared when polymorphonuclear leukocyte chemotaxis was depressed. Ineffective chemotaxis combined with high-colonization density and inadequate stratum corneum barrier during exacerbations of atopic dermatitis may lead to mild staphylococcal infections. These infections appear to have no systemic effects but possibly the considerable associated pruritis could worsen the atopic dermatitis. Occasional patients may require intermittent or continuous antibiotic therapy. (<i>Arch Dermatol</i>113:1383-1386, 1977)

Fucidin in patients on haemodialysis.

Fucidin is useful against ;antibiotic-resistant staphylococci' which are a major problem in causing shunt site infections in patients on chronic intermittent haemodialysis for end-stage renal failure. A new form of intravenous fucidin has been used in vivo in three patients on haemodialysis, and also in experiments in vitro in order to assess its dialysing properties. The experiments in vitro show that some fucidin does cross the dialyser membrane but, in the patients studied, adequate serum levels were maintained throughout a 10-hour haemodialysis. A single intravenous dose of Fucidin is, therefore, adequate for treating ;antibiotic-resistant' staphylococcal infections in patients during haemodialysis.