PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Staphylococcus”

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 415 records · Page 23Linked to original sources

[Survey on drug resistance of Staphylococcus to commonly used antibiotics].

OBJECTIVE: To obtain primary knowledge of drug resistance of Staphylococcus, especially methicillin-resistant Staphylococcus (MRS), so as to facilitate clinical decision over the choice of appropriate antibiotics. METHOD: A total of 105 strains of Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative Staphylococcus,were isolated from blood, sputum, pus and secretion sample from in-patients of Nanfang Hospital from January to July, 2002, and their status of drug-resistance was examined. RESULTS: MRS was isolated from 68.8% of the samples, and 69.6% of these isolates were methicillin-resistant Staphylococcus aureus (MRSA) and 63.3% resistant Staphylococcus epidermidis (MRSE). The rate of multi-drug resistance for MRS was much higher than that for methicilllin-susceptible Staphylococcus (MSS), and MRSA showed high multidrug resistance rates (all>50%) to the antibiotics erythromycin, imipenem, amikacin, SXT, ciprofloxacin, which fell into 4 categories according to their different antibiotic mechanisms. CONCLUSIONS: The prevalence and high MDR rate of MRS isolated form the samples suggest that in cases of infection, identification of the pathogenic bacterium should be routinely performed. Besides controlling MRS infection, importance should also be given to its prevention.

Anti-Bacterial Agents↗

[Epidemiology of methicillin-resistant Staphylococcus aureus at the Kenézy Hospital between 1999 and 2004].

INTRODUCTION: The prevention of the spread of multiresistant microorganisms, especially methicillin-resistant Staphylococcus aureus is the main problem of epidemiology in our era. Kenézy Hospital was among the firsts to deal with the laboratory diagnosis of methicillin-resistant Staphylococcus aureus infection in Hungary, looking for the possibilities to isolate, and detect methicillin-resistant Staphylococcus aureus in patients (colonised and infected), and to provide for them proper treatment and complex management. AIMS: The authors aimed to help the work of infection control professionals by sharing their experience and through the analysis of their data. METHODS: The authors analysed the data on the incidence of infection of methicillin-resistant Staphylococcus aureus positive patients from 1999 at the Kenézy Hospital and investigated the effect of infection control policies on the incidence of infection. RESULTS: On the hospital level the lowest frequency of methicillin-resistant Staphylococcus aureus positive patients was found in 2003. The authors identified the Rehabilitation, the Traumatology and the Intensive Care Department as high risk units. The higher incidence was caused by the endemic occurrence of the disease at the specific wards. The methicillin-resistant Staphylococcus aureus infections became more severe every year, demonstrated by the increasing positivity rate of the blood cultures. Based on the identification of the most frequent phage types in each year, an epidemic strain, unlike in England, could not be found at the Kenézy Hospital. CONCLUSIONS: The number of methicillin-resistant Staphylococcus aureus positive patients at an institute depends on the institute's efforts to effectively apply microbiological screening. At a department where methicillin-resistant Staphylococcus aureus is endemic, elimination of the agent and that of the endemia are difficult tasks for the infection control team.

Cross Infection↗

A comparison between septic bursitis caused by Staphylococcus aureus and those caused by other organisms.

Septic bursitis is an infection that usually involves olecranon and prepatellar bursae. Staphylococcus aureus is responsible for around 80% of cases. However, information regarding bursitis caused by non-Staphylococcus aureus microorganisms (NSAB) is scant. In this paper we describe the characteristics of NSAB and emphasise differences between these and Staphylococcus aureus bursitis (SAB). A retrospective study of all cases with septic bursitis seen between January 1991 and June 1998 at one university hospital was conducted. Only cases in which bursal fluid culture yielded growth of a microorganism were analysed. A literature review was conducted for completeness. Fifty-seven episodes of septic bursitis in 56 patients were studied: 47 of these were caused by Staphylococcus aureus and 11 by non-Staphylococcus aureus microorganisms. Forty-three SAB patients were male (91%). Mean age at diagnosis was 50 years (range 20-85 years). The presentation of bursitis had a seasonal trend, with a peak in the summer. Twenty-three patients (51%) had occupations involving frequent or sustained pressure on the bursae. Other risk factors were recent trauma in 11 (23%), alcoholism in six (13%), pre-existing bursal disease in five (11%), and chronic obstructive pulmonary disease in four (9%). There were 20 cases of olecranon bursitis (43%), 25 of prepatellar bursitis (53%) and two of first metatarsophalangeal bursitis. Characteristics of patients from the literature review were similar. Eight NSAB patients (73%) were male. Mean age at diagnosis was 46.9 (range 29-83 years). Two patients were plumbers and one a stonemason. Five (45%) had neither putative systemic nor local risk factors. There were five olecranon (45%), five prepatellar (45%), and one external malleolus bursitis. Infection by a mixed flora was common. Unlike SAB, the presentation of cases did not have a seasonal trend. The clinical spectrum of non-Staphylococcus aureus bursitis (NSAB) differs from that of Staphylococcus Aureus bursitis (SAB), and this should be considered in the initial diagnosis of septic bursitis.

Adult↗

Evaluation of the mecA femB duplex polymerase chain reaction for detection of methicillin-resistant Staphylococcus aureus.

This study systematically evaluated a recently described duplex polymerase chain reaction test for methicillin-resistant Staphylococcus aureus with 25 different German epidemic strains of methicillin-resistant Staphylococcus aureus and 66 staphylococci other than methicillin-resistant Staphylococcus aureus, including 17 different coagulase-negative staphylococcal species and subspecies, that were either oxacillin susceptible or oxacillin resistant. The results were compared with those of conventional cultural identification and susceptibility testing. Of the 91 isolates tested, all 25 confirmed strains of methicillin-resistant Staphylococcus aureus were identified correctly. None of the remaining strains of methicillin-susceptible Staphylococcus aureus was misidentified as methicillin-resistant Staphylococcus aureus. It was concluded that the duplex polymerase chain reaction appears to offer a time-saving and accurate method of detection of methicillin-resistant Staphylococcus aureus.

Bacterial Proteins↗

Methicillin-resistant Staphylococcus aureus infection of percutaneous endoscopic gastrostomy sites.

BACKGROUND: Antibiotic prophylaxis for percutaneous endoscopic gastrostomy insertion remains controversial. The bacteriology of peristomal infection following percutaneous endoscopic gastrostomy insertion has been poorly studied, leading to uncertainty regarding the optimum choice of antibiotic for prophylaxis. AIM: To investigate the bacteriology of peristomal infection following percutaneous endoscopic gastrostomy insertion and to determine the contribution of methicillin-resistant Staphylococcus aureus. METHODS: Nasal and pharyngeal swabs were taken from a consecutive series of patients prior to percutaneous endoscopic gastrostomy insertion over a 6-month period. Bacterial colonization and infection at the peristomal site were prospectively evaluated at days 2/3 and 7 post-insertion. RESULTS: Thirty-one patients underwent percutaneous endoscopic gastrostomy insertion (mean age, 68 years; cerebrovascular disease, 52%). Naso-pharyngeal colonization by methicillin-resistant Staphylococcus aureus (35%) invariably led to peristomal colonization following percutaneous endoscopic gastrostomy insertion. Peristomal infection occurred in eight (26%) cases (seven (88%) methicillin-resistant Staphylococcus aureus- positive). Peristomal infection was significantly more likely to occur in patients with naso-pharyngeal methicillin-resistant Staphylococcus aureus colonization (odds ratio, 10.8; 95% confidence interval, 1.6-70.9). CONCLUSIONS: Naso-pharyngeal methicillin-resistant Staphylococcus aureus colonization invariably predicts peristomal methicillin-resistant Staphylococcus aureus colonization following percutaneous endoscopic gastrostomy insertion, and is associated with an increased peristomal infection rate. Currently recommended antibiotic prophylaxis regimens may be inappropriate in institutions with significant methicillin-resistant Staphylococcus aureus colonization rates.

Aged↗

Staphylococcus aureus and endoscopic sinus surgery.

PURPOSE OF REVIEW: The current recommendation for the choice of empiric antibiotic therapy of chronic rhinosinusitis is based on the bacteriology of acute rhinosinusitis. Staphylococcus aureus has been found consistently in cultures from patients with chronic rhinosinusitis. New studies have examined the role of Staphylococcus aureus in the pathogenesis and clinical course of chronic rhinosinusitis, both before and after surgical therapy. The consequence of antibiotic resistance, on the course of chronic rhinosinusitis and its treatment, has also been examined. RECENT FINDINGS: Several recent studies have confirmed past literature demonstrating a high incidence of sinus cultures positive for Staphylococcus aureus growth in patients with chronic rhinosinusitis. Moreover, one study reported that Staphylococcus aureus is common in patients with persistent chronic rhinosinusitis after endoscopic sinus surgery. These studies, however, have not shown that this bacterium is a significant factor in the development of chronic rhinosinusitis or a predictor of the severity of symptoms. Other studies did not support the notion of increased antibiotic resistance in chronic rhinosinusitis, although there is some evidence that antibiotic resistance may lead to refractory cases of the disease. The standard treatment, of multiple courses of empiric antibiotics followed by surgery, was not shown to increase the prevalence of methicillin-resistant Staphylococcus aureus. SUMMARY: A review of recent literature shows a high incidence of positive cultures for Staphylococcus aureus from the sinuses of patients with chronic rhinosinusitis, both before and after surgery, but has not produced convincing evidence that Staphylococcus aureus has a significant role in the pathogenesis or clinical course of the disease.

Chronic Disease↗

Evaluation of the Rapid Mastitis Test for identification of Staphylococcus aureus and Streptococcus agalactiae isolated from bovine mammary glands.

A latex agglutination test system (Rapid Mastitis Test [RMT]; Immucell, Portland, Maine) containing reagents for the identification of Staphylococcus aureus and Streptococcus agalactiae from bovine intramammary infections was evaluated with 527 staphylococcal and 267 streptococcal isolates. The RMT Staphylococcus aureus reagent detected 94.2% of 242 Staphylococcus aureus isolates, 80% of 25 Staphylococcus intermedius isolates, and 42.8% of 21 tube coagulase-positive Staphylococcus hyicus isolates. All Streptococcus agalactiae isolates were correctly identified by the RMT Streptococcus agalactiae reagent. Cross-reactions were observed with one Streptococcus dysgalactiae and three Streptococcus uberis strains. The RMT was found to be an acceptable method for the detection of Staphylococcus aureus and Streptococcus agalactiae isolated from bovine mammary glands. The occurrence of coagulase-positive staphylococci other than Staphylococcus aureus requires biochemical testing for species level identification.

Animals↗

[Mutant prevention concentrations of fluoroquinolones for Staphylococcus aureus].

OBJECTIVE: To establish a method to measure mutant prevention concentration (MPC) in vitro, and to measure MPC of fluoroquinolones for staphylococcus aureus. METHODS: The staphylococcus aureus strain ATCC25923 and 20 ciprofloxacin-susceptible clinical isolates were enriched in broth, and the bacterial concentrations were adjusted to 10(10) colony forming units per milliliter. The minimal inhibitory concentration (MIC), MIC for 99% of input cells (MIC99), provisional MPC (MPCpr) and MPC of moxifloxacin, gatifloxacin, pasufloxacin and ciprofloxacin for staphylococcus aureus were determined by agar plates dilution method. RESULTS: The MPC of moxifloxacin, gatifloxacin, pasufloxacin and ciprofloxacin for staphylococcus aureus strain ATCC25923 were 0.18, 0.3, 0.75 and 1.8 microg/ml, and the MPC/MIC99 were 9.0, 7.5, 8.0 and 10.6 respectively. The MPC for 90% of the isolates (MPCpr90) of moxifloxacin, gatifloxacin, pasufloxacin and ciprofloxacin for 20 staphylococcus aureus clinical isolates were 1, 1, 4 and 8 microg/ml, and the MPCpr90/MIC90 were 8, 8, 16 and 16 respectively. CONCLUSION: The capacity of moxifloxacin and gatifloxacin for restricting the selection of staphylococcus aureus resistant mutants were stronger than that of pasufloxacin and ciprofloxacin. Combined with pharmacokinetic parameters, moxifloxacin and gatifloxacin may restrict the selective enrichment of resistant mutants among ciprofloxacin-susceptible staphylococcus aureus clinical isolates, and ciprofloxacin is expected to selectively enrich mutants easily.

Anti-Infective Agents↗

Biochemical and molecular characterization of Staphylococcus simulans lipase.

Staphylococcus simulans strain secretes a non-induced lipase in the culture medium. Staphylococcus simulans lipase (SSL), purified to homogeneity, is a tetrameric protein (160 kDa) corresponding to the association of four lipase molecules. The 30 N-terminal amino acid residues were sequenced. This sequence is identical to the one of Staphylococcus aureus PS54 lipase (SAL PS54) and exhibits a high degree of homology with Staphylococcus aureus NCTC8530 lipase (SAL NCTC8530), Staphylococcus hyicus lipase (SHL) and Staphylococcus epidermis RP62A lipase (SEL RP62A) sequences. But the cloning and sequencing of the part of the gene encoding the mature lipase show some differences from SAL PS54 sequence, which suggest that it is a new sequence. The lipase activity was maximal at pH 8.5 and 37 degrees C. SSL is able to hydrolyze triacylglycerols without chain length specificity. A specific activity of about 1000 U/mg was measured on tributyrin or triolein as substrate at 37 degrees C and at pH 8.5 in the presence of 3 mM CaCl(2). In contrast to other staphylococcal lipases previously characterized, Ca(2+) is not required to express the activity of SSL. SSL was found to be stable between pH 4 and pH 9. The enzyme is inactivated after a few minutes when incubated at 60 degrees C. Using tripropionin as substrate, SSL does not present the interfacial activation phenomenon. In contrast to many lipases, SSL is able to hydrolyze its substrate in the presence of bile salts or amphiphilic proteins.

Amino Acid Sequence↗

Effects of teat dipping on intramammary infections by staphylococci other than Staphylococcus aureus.

Effects of intramammary infections in herds 1) either not teat dipping or postmilking teat dipping with either 2) linear dodecyl benzene sulfonic acid, 3) chlorhexidine, or 4) iodophor containing products were determined. Duplicate quarter foremilk samples were collected once from all lactating cows in 16 herds, four for each practice. Mean percentage of quarters infected with Staphylococcus species other than Staph. aureus was 11.0 in herds not teat dipping and 7.2 in herds teat dipping. Prevalence of Staphylococcus species intramammary infections in herds teat dipping with linear dodecyl benzene sulfonic acid was comparable to herds not teat dipping and greater than in herds using chlorhexidine and iodophor. The predominant Staphylococcus species in herds not teat dipping was Staph. epidermidis (37.1%). Staphylococcus hyicus constituted 48.5% of total Staphylococcus species intramammary infections in herds teat dipping and 12.4% in herds not teat dipping. Differences were not observed among SCC for quarters infected with different Staphylococcus species. Application of germicidal teat dips appeared to have selectively altered both prevalence and distribution of Staphylococcus species intramammary infections.

Animals↗

Expression of the gene encoding protein A in Staphylococcus aureus and coagulase-negative staphylococci.

Two shuttle vectors containing the gene for protein A (spa) from Staphylococcus aureus have been constructed to study expression of the gene in various strains of S. aureus and in the coagulase-negative species Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus xylosus. One plasmid, pSPA15, contains the complete structural gene for protein A, which binds to the cell wall in various Staphylococcus species. The other plasmid, pSPA16, codes for a truncated protein A lacking the C-terminal part called region X. The latter is exclusively extracellular in all Staphylococcus species tested, which confirms the importance of region X for cell wall binding. The expression of the plasmid-coded protein A in various strains of S. aureus is strongly correlated to the expression of the chromosomal spa gene. The coagulase-negative species expressing plasmid-encoded protein A produce 12 to 30% of the amount coded by the chromosomal spa gene in S. aureus strains Cowan I and A676.

Amino Acid Sequence↗

Effect of milk on fibronectin and collagen type I binding to Staphylococcus aureus and coagulase-negative staphylococci isolated from bovine mastitis.

Tryptic soy broth (TSB)-grown cells of Staphylococcus aureus isolated from acute and chronic bovine mastitis bound mainly 125I-fibronectin (Fn) [corrected], whereas strains of nine species of coagulase-negative staphylococci showed a predominant interaction with 125I-collagen (Cn) [corrected] type I. A particle agglutination assay (PAA) was used to examine the interaction of coagulase-negative staphylococci with 125I-Fn and 125I-Cn immobilized on latex. All 368 coagulase-negative staphylococci demonstrated high 125I-Cn and moderate to low 125I-Fn interactions in the PAA. Cn-PAA reactivity was high among strains of Staphylococcus xylosus (84.2%), Staphylococcus simulans (77.8%), Staphylococcus epidermidis (76.7%), and Staphylococcus hyicus (74.3%), whereas all six Staphylococcus capitis strains clumped Cn-PAA reagent. Incubating TSB-grown cells in 10% skim milk for 1 h decreased the 125I-Fn- and 125I-Cn-binding affinity in most of the S. aureus and coagulase-negative staphylococci, while growth in 10% skim milk for 18 h resulted in more than 90% decrease or complete loss of interaction with these proteins. Decreased 125I-Fn binding in the presence of milk was correlated with protease production but not with 125I-Cn binding.

Acute Disease↗

Staphylococcus aureus nasal carriage as a marker for subsequent staphylococcal infections in intensive care unit patients.

From January to December 1994, 752 consecutive patients admitted to intensive care units (ICU) for more than two days were studied prospectively for Staphylococcus aureus colonization and infection. Nasal swabs were obtained at admission and weekly during the ICU stay. At ICU admission 166 patients (22.1%) were Staphylococcus aureus nasal carriers, while 586 were free of nasal colonization. Of the 166 nasal carriers, 163 harbored methicillin-sensitive Staphylococcus aureus (MSSA) and three methicillin-resistant Staphylococcus aureus (MRSA). During the ICU stay 24 of the 586 noncolonized patients became nasal carriers (11 MSSA and 13 MRSA), and one nasal carrier initially colonized by MSSA was reconlonized by MRSA. Staphylococcal infections were documented in 51 (6.8%) of the total 752 patients. After 14 days of ICU stay, the probability of developing staphylococcal infections was significantly higher for those patients who were nasal carriers at ICU admission than for those found to be initially negative (relative risk 59.6, 95% CI 20.37-184.32; p < 0.0001). In patients with ICU-acquired nasal colonization, most infections were documented prior to or at the time of the detection of the nasal colonization; thus, in this group of patients nasal carriage showed a lower predictive value for subsequent Staphylococcus aureus infections that that described classically. Paired isolates of nasal colonizing and clinical strains were studied by pulsed-field gel electrophoresis (PFGE) and mecA polymorphism analysis in 30 patients; identity was demonstrated in all but two patients. The results suggest that, outside the setting of an outbreak of MRSA, the detection of Staphylococcus aureus nasal carriers on admission may be particularly useful in identifying those patients who are at high risk for developing staphylococcal infections during their ICU stay.

Biomarkers↗

Comparative evaluation of a latex test for the identification of Staphylococcus aureus.

A rapid latex agglutination test, Staphaurex, was tested for its ability to identify Staphylococcus aureus using 72 reference strains and 785 clinical isolates of the family Micrococcaceae. All reference strains of Staphylococcus aureus were Staphaurex-positive. Non-Staphylococcus aureus reference strains were negative. Using clinical strains, the results of the Staphaurex test were compared with the results of other tests commonly used to identify Staphylococcus aureus. A total of 393 clinical isolates were classified as Staphylococcus aureus. The Staphaurex, slide coagulase, tube coagulase/human plasma and tube coagulase/rabbit plasma tests correctly identified 98%, 93.6%, 93.6% and 97.5% of the Staphylococcus aureus strains, respectively. The performance of the Staphaurex test, in terms of sensitivity and specificity, was significantly better than the slide coagulase test. It was as sensitive and almost as specific as the tube coagulase rabbit test and more sensitive than the tube coagulase human test.

Evaluation Studies as Topic↗

Immunochemical analysis of the extracellular slime substance of Staphylococcus epidermidis.

To analyze immunochemically the extracellular slime substance of Staphylococcus epidermidis, rabbits were repeatedly immunized with the crude slime extract isolated from an adherent, slime-producing clinical Staphylococcus epidermidis strain. Immunoelectron microscopy demonstrated that the target antigens of the resulting antibodies were located in the extracellular slime-like layer of bacterial cells. When these target antigens were characterized by immunoblotting, a variety of antigens were detected, including many with molecular masses higher than 80 kilodaltons and also a predominant one with a molecular mass of 30 kilodaltons. No characteristic differences were observed between the tube adherence test positive and negative Staphylococcus epidermidis isolates. Although there was variation in the number and intensity of high molecular mass antigens, such variations did not correlate with the tube adherence test. Of the 110 Staphylococcus epidermidis isolates studied, 106 (96%) expressed the 30-kilodalton antigen. This component was found in no other Staphylococcus spp. examined in the study. The bacterial component was not only easily detached from bacterial cells but also water-soluble, characteristics implicating a slime-like nature. Further studies are needed to definitively establish the origin and nature of the 30-kilodalton Staphylococcus epidermidis-specific component, and determine its potential benefit as a diagnostic tool.

Antibodies, Bacterial↗

Detection of borderline oxacillin-resistant Staphylococcus aureus and differentiation from methicillin-resistant strains.

Eighty-eight Staphylococcus aureus clinical isolates meeting criteria for borderline oxacillin resistance (intermediate susceptibility or resistance to oxacillin but susceptibility to amoxicillin/clavulanic acid upon disk diffusion testing) were studied to determine optimal test techniques and conditions for differentiating borderline oxacillin-resistant Staphylococcus aureus (BORSA) from methicillin-resistant Staphylococcus aureus (MRSA). Further testing revealed three distinct resistance patterns: 61 strains (69%) consistently met BORSA criteria and had average beta-lactamase levels five- to six-fold higher than oxacillin-susceptible controls; 11 strains (13%) were markedly heteroresistant MRSA with delayed appearance of resistant colonies leading to spurious susceptibility to amoxicillin/clavulanic acid; 16 strains (18%) appeared to be oxacillin-susceptible on repetitive testing. Under conditions used to elicit intrinsic methicillin resistance in Staphylococcus aureus, a large percentage of BORSA appeared resistant to amoxicillin/clavulanic acid. This clearly shows that BORSA may be misidentified as MRSA while heteroresistant MRSA may appear to be BORSA. It is concluded that amoxicillin/clavulanic acid zone sizes should be measured after a full 24 hours of incubation, that susceptibility testing of Staphylococcus aureus under certain environmental conditions should be interpreted with caution, and that MIC testing is the most reliable technique for differentiating these two resistance patterns in Staphylococcus aureus.

Amoxicillin↗

Proteolytic activity of Staphylococcus aureus strains isolated from the colonized skin of patients with acute-phase atopic dermatitis.

Staphylococcus aureus strains isolated from the colonized skin lesions of 26 patients with acute-phase atopic dermatitis were reported to produce various extracellular proteolytic enzymes. Using the skim-milk-agar culture plating method, it was shown that 97% of the strains (65 of 67 examined) produced proteolytic activity, with 61% (42 strains) producing activity comparable to that of the proteolytically hyperactive reference strain Staphylococcus aureus V8. This observation was confirmed by azocasein degradation with culture supernatants, which indicated that 91% of the strains produced extracellular proteinases and 43% exceeded the 2% activity threshold of the reference strain. Control strains were isolated from the nose vestibules of 18 healthy carriers; the proteolytic activity of these strains never exceeded 2.5% of the activity of the reference strain. In 54% of the patients examined ( n=14), the activity of the strains was higher than that determined for the isolates from the control group. The combined use of assays incorporating azocasein and a synthetic chromogenic substrate, N-CBZ-Phe-Leu-Glu- pNA, showed that two staphylococcal enzymes, Staphylococcus aureus metalloproteinase (SAMP) and Staphylococcus aureus serine proteinase (SASP), contributed to the total proteolytic activity released by the strains examined. The contribution of each of the two enzymes varied greatly between different isolates. The undamaged skin of the patients was not colonized with Staphylococcus aureus. The presence of several strains with atypical proteinase characteristics was also reported, suggesting the possible involvement of enzymes other than serine- and metallo-proteinases in the proteolytic activity of Staphylococcus aureus. Taken together, the results of the study imply that staphylococcal proteinases may contribute to the pathogenicity of atopic dermatitis.

Acute Disease↗

High prevalence of superantigens associated with the egc locus in Staphylococcus aureus isolates from patients with atopic eczema.

The present study was aimed at identifying a possible correlation between disease severity and colonization with superantigen-producing Staphylococcus aureus strains in patients with atopic eczema. To this end, Staphylococcus aureus strains from 91 patients with atopic eczema were screened for various staphylococcal superantigens such as SEA, SEB, SEC, SED, TSST1, the recently described enterotoxin gene cluster egc (which encodes the enterotoxins SEG, SEI, SEK, SEM, and SEO), and the see, seh, and sej loci. Swabs were taken from seven different sites in each patient. The rate of colonization with Staphylococcus aureus was 87.9%. Of those patients colonized, 35% were colonized with more than one different strain. Of the 120 genetically different strains investigated, the egc locus was found in 48.3% and the sej locus in 7.5%. The see and seh loci were not found in any strain. The presence of the classical superantigens SEA-SED or TSST1 was found in 38.3%. Overall, 71.3% of the Staphylococcus aureus-positive patients harbored at least one superantigen-producing strain on their skin. There was no difference in the prevalence of superantigens between atopic eczema patients and healthy volunteers. Moreover, there was no difference in the extent of disease expression between patients colonized by superantigen-positive Staphylococcus aureus strains and those with superantigen-negative strains as measured by the SCORAD system. However, patients colonized with Staphylococcus aureus had a significantly higher SCORAD score than those not colonized.

Adolescent↗