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C von Eiff

Publications and source records attributed to C von Eiff.

At least 19 recordsLinked to original sources
PubMed2002

Osteopetrosis, femoral fracture, and chronic osteomyelitis caused by Staphylococcus aureus small colony variants (SCV) treated by girdlestone resection--6-year follow-up.

Chronic osteomyelitis caused by Staphylococcus aureus small colony variants in combination with osteopetrosis is a unique combination of disorders that confronted us with major challenges. The therapeutic approach included four serial debridements and antimicrobial therapy. The aggressive treatment led to an instability of the brittle and hard osteopetrotic bone, and after 11 weeks, a fracture of the femoral neck occurred. A salvage procedure of the femur was performed, and the cultures obtained during this intervention remained negative. At a 6-year follow-up, the girdlestone situation still showed an acceptable functional outcome without any recurrence of osteomyelitis.

Adult↗
PubMed2001

Intracellular persistence of Staphylococcus aureus small-colony variants within keratinocytes: a cause for antibiotic treatment failure in a patient with darier's disease.

Intracellular persistence assays were performed with small-colony variants (SCVs) derived from a patient with Darier's disease from whom different phenotypes and genotypes of Staphylococcus aureus were isolated over a 28-month period; the assays revealed that >100-fold more SCV cells persisted intracellularly relative to the normal phenotype. The presence of intracellular S. aureus SCVs may protect against host defenses and antibiotic therapy and thus may have contributed to this patient's very prolonged skin infection.

DNA, Bacterial↗
PubMed2001

Nasal carriage as a source of Staphylococcus aureus bacteremia. Study Group.

BACKGROUND: The consequences of infection with Staphylococcus aureus can be severe, so strategies for prevention are important. We examined S. aureus isolates from blood and from nasal specimens to determine whether the organisms in the bloodstream originated from the patient's own flora. METHODS: In a multicenter study, swabs for culture were obtained from the anterior nares of 219 patients with S. aureus bacteremia. A total of 723 isolates were collected and genotyped. In a second study, 1640 S. aureus isolates from nasal swabs were collected over a period of five years and then compared with isolates from the blood of patients who subsequently had S. aureus bacteremia. RESULTS: In the multicenter study of S. aureus bacteremia, the blood isolates were identical to those from the anterior nares in 180 of 219 patients (82.2 percent). In the second study, 14 of 1278 patients who had nasal colonization with S. aureus subsequently had S. aureus bacteremia. In 12 of these 14 patients (86 percent), the isolates obtained from the nares were clonally identical to the isolates obtained from blood 1 day to 14 months later. CONCLUSIONS: A substantial proportion of cases of S. aureus bacteremia appear to be of endogenous origin since they originate from colonies in the nasal mucosa. These results provide support for strategies to prevent systemic S. aureus infections by eliminating nasal carriage of S. aureus.

Adolescent↗
PubMed2001

Survey of staphylococcal enterotoxin genes, exfoliative toxin genes, and toxic shock syndrome toxin 1 gene in non-Staphylococcus aureus species.

The aim of this study was to analyze the presence of staphylococcal exotoxin genes in staphylococci other than Staphylococcus aureus. Whereas for Staphylococcus aureus a large spectrum of different exotoxins responsible for toxin-mediated diseases has been described, only few and conflicting data are available regarding toxin production in all other staphylococcal species. A collection of clinical non-Staphylococcus aureus staphylococcal isolates were systematically screened for the presence of genes for toxic shock syndrome toxin 1, exfoliative toxins, and classical enterotoxins by using multiplex polymerase chain reaction enzyme immunoassays. In a total of 461 isolates of 18 different (sub)species derived from clinical specimens, no toxin gene sequences were amplified. The results indicate that the occurrence of toxin genes involved in staphylococcal toxin-mediated diseases is at least very rare in human-derived isolates of non-Staphylococcus aureus species.

Bacterial Toxins↗
PubMed2001

Enterotoxigenic potential of Staphylococcus intermedius.

Staphylococcal food poisoning (SFP) caused by enterotoxigenic staphylococci is one of the main food-borne diseases. In contrast to Staphylococcus aureus, a systematic screening for the enterotoxins has not yet been performed on the genomic level for the coagulase-positive species S. intermedius. Therefore, the enterotoxigenic potential of 281 different veterinary (canine, n = 247; equine, n = 23; feline, n = 9; other, n = 2) and 11 human isolates of S. intermedius was tested by using a multiplex PCR DNA-enzyme immunoassay system targeting the staphylococcal enterotoxin genes sea, seb, sec, sed, and see. Molecular results were compared by in vitro testing of enterotoxin production by two immunoassays. A total of 33 (11.3%) S. intermedius isolates, including 31 (12.6%) canine isolates, 1 equine isolate, and 1 human isolate, tested positive for the sec gene. In vitro production of the respective enterotoxins was detected in 30 (90.9%) of these isolates by using immunological tests. In contrast, none of 65 veterinary specimen-derived isolates additionally tested and comprising 13 (sub)species of coagulase-negative staphylococci were found to be enterotoxigenic. This study shows on both molecular and immunological levels that a substantial number of S. intermedius isolates harbor the potential for enterotoxin production. Since evidence for noninvasive zoonotic transmission of S. intermedius from animal hosts to humans has been documented, an enterotoxigenic role of this microorganism in SFP via contamination of food products may be assumed.

Animals↗
PubMed2001

Analogs of Eap protein are conserved and prevalent in clinical Staphylococcus aureus isolates.

Map and Eap are secreted Staphylococcus aureus proteins that interact with various extracellular matrix molecules. PCR analysis using map primers yielded positive reactions in 97.9% of S. aureus isolates but not in Staphylococcus epidermidis isolates. Cloning and sequencing of the conferring genes revealed a high degree of overall homology combined with size variability of the gene product due to various repeat numbers and early translation termination in a poly(A) region. Thus, Map and Eap may provide a potential novel tool for S. aureus identification and typing.

Amino Acid Sequence↗
PubMed2001

Identification and characterization of a novel 38.5-kilodalton cell surface protein of Staphylococcus aureus with extended-spectrum binding activity for extracellular matrix and plasma proteins.

The ability to attach to host ligands is a well-established pathogenic factor in invasive Staphylococcus aureus disease. In addition to the family of adhesive proteins bound to the cell wall via the sortase A (srtA) mechanism, secreted proteins such as the fibrinogen-binding protein Efb, the extracellular adhesion protein Eap, or coagulase have been found to interact with various extracellular host molecules. Here we describe a novel protein, the extracellular matrix protein-binding protein (Emp) initially identified in Western ligand blots as a 40-kDa protein due to its broad-spectrum recognition of fibronectin, fibrinogen, collagen, and vitronectin. Emp is expressed in the stationary growth phase and is closely associated with the cell surface and yet is extractable by sodium dodecyl sulfate. The conferring gene emp (1,023 nucleotides) encodes a signal peptide of 26 amino acids and a mature protein of a calculated molecular mass of 35.5 kDa. Using PCR, emp was demonstrated in all 240 S. aureus isolates of a defined clinical strain collection as well as in 6 S. aureus laboratory strains, whereas it is lacking in all 10 S. epidermidis strains tested. Construction of an allelic replacement mutant (mEmp50) revealed the absence of Emp in mEmp50, a significantly decreased adhesion of mEmp50 to immobilized fibronectin and fibrinogen, and restoration of these characteristics upon complementation of mEmp50. Emp expression was also demonstrable upon heterologous complementation of S. carnosus. rEmp expressed in Escherichia coli interacted with fibronectin, fibrinogen, and vitronectin in surface plasmon resonance experiments at a K(d) of 21 nM, 91 nM, and 122 pM, respectively. In conclusion, the biologic characterization of Emp suggests that it is a member of the group of secreted S. aureus molecules that interact with an extended spectrum of host ligands and thereby contribute to S. aureus pathogenicity.

Adhesins, Bacterial↗
PubMed2001

Nationwide German multicenter study on the prevalence of antibiotic resistance in streptococcal blood isolates from neutropenic patients and comparative in vitro activities of quinupristin-dalfopristin and eight other antimicrobials.

In a prospective multicenter study (1996 to 1999), 156 episodes of bacteremic streptococcal infections of neutropenic patients were evaluated. Streptococcus oralis (26.3%), S. pneumoniae (26.3%), S. agalactiae (11.5%), S. mitis (9%), and S. pyogenes (5.8%) were the predominant species. Four strains (2.6%) were found to be intermediately resistant to penicillin. One strain (0.6%) was found to be highly resistant to penicillin (MIC, 8 mg/liter). Reduced susceptibility to penicillin was detected among S. oralis (14.6%), S. mitis (7.1%), and S. pneumoniae (4.9%) isolates but was not recorded among S. agalactiae and S. pyogenes. Resistance rates and intermediate resistance rates for other antimicrobials were as follows (all species): amoxicillin, 1.3 and 3.2%; erythromycin, 16 and 2.6%; clindamycin, 5.8 and 0%; ciprofloxacin, 1.9 and 7.7%. Quinupristin-dalfopristin showed good in vitro activity against most streptococcal isolates (MIC at which 50% of the isolates were inhibited [MIC(50)], 0.5 mg/liter; MIC(90), 1 mg/liter, MIC range, 0.25 to 4 mg/liter).

Adolescent↗
PubMed2001

Coagulase-negative staphylococci. Pathogens have major role in nosocomial infections.

Coagulase-negative staphylococci live naturally on the skin and mucous membranes of humans and are therefore often found in clinical specimens. Distinguishing clinically significant, pathogenic strains from contaminant strains is one of the major challenges facing clinical microbiology laboratories. S epidermidis and other novobiocin-susceptible coagulase-negative staphylococci have emerged as a major cause of nosocomial infections, particularly of nosocomial bacteremia in immunocompromised patients. S epidermidis also is common in injecting drug users, who are particularly susceptible to right-sided endocarditis, and--most important--in patients with such indwelling foreign bodies as intravenous catheters. Depending on the kind of device and its insertion site, different infection syndromes generate a variety of clinical presentations. In these patients, the host defense mechanisms often seem unable to handle the infection and, in particular, to eliminate the staphylococci from the infected device because of a biofilm on the foreign body surface. S saprophyticus, the most commonly isolated bacterium of the novobiocin-resistant coagulase-negative staphylococci, is a common pathogen of the urogenital tract; it generally infects immunocompetent patients, particularly young, sexually active men and women.

Coagulase↗
PubMed2000

Distribution of macrolide-resistance genes in Staphylococcus aureus blood-culture isolates from fifteen German university hospitals. M.A.R.S. Study Group. Multicentre Study on Antibiotic Resistance in Staphylococci.

The purpose of the study was to analyze the distribution of the macrolide-resistance genes in 134 erythromycin-resistant Staphylococcus aureus blood-culture isolates collected at 15 German university hospitals. The most prevalent resistance gene was ermC (68/134; 50.7%), followed by ermA (52/134; 38.8%), ereB (10/134; 7.5%), and mrsA/msrB (4/134; 6%). The least common genes were ermB (3/134; 2.2%) and ereA (1/134; 0.7%). Overall, resistance to erythromycin was predominantly due to the presence of two erm genes, although with different distributions, depending on the methicillin-resistance pattern.

Anti-Bacterial Agents↗
PubMed2000

Nationwide German multicenter study on prevalence of antibiotic resistance in staphylococcal bloodstream isolates and comparative in vitro activities of quinupristin-dalfopristin.

Antibiotic-resistant gram-positive bacteria have become an increasing problem in the last two decades. In order to evaluate the prevalence of antibiotic resistance in staphylococcal bloodstream isolates in Germany, 2,042 staphylococci collected in 21 tertiary-care hospitals were investigated during a 3-year period (March 1996 to March 1999). Altogether, 1,448 S. aureus isolates and 594 coagulase-negative staphylococci (CoNS) that comprised 13 different species were included. Furthermore, the antistaphylococcal activities of quinupristin-dalfopristin were compared with those of eight other compounds by the broth microdilution method. The rates of oxacillin resistance in Staphylococcus aureus, S. epidermidis, S. haemolyticus, and other CoNS were 13.5, 69, 90, and 34%, respectively. In oxacillin-resistant strains high rates of resistance (up to 100%) to erythromycin, clindamycin, ciprofloxacin, and gentamicin were also observed. However, no strain appeared to be resistant to vancomycin or quinupristin-dalfopristin. The streptogramin combination exhibited excellent in vitro activity against all staphylococcal species tested, regardless of the patterns of resistance to other drug classes. In terms of MICs at which 90% of the isolates are inhibited, quinupristin-dalfopristin was 2 times more active against S. aureus isolates, 4 to 16 times more active against S. haemolyticus, and 8 to 32 times more active against S. epidermidis than vancomycin or teicoplanin.

Anti-Bacterial Agents↗
PubMed2000

Small colony variants of Staphylococci: a link to persistent infections.

In prospective studies, Staphylococcus aureus small-colony variants (SCVs) have been linked to persistent and recurrent infections. SCVs are a naturally occurring subpopulation often defective in electron transport which may be identified in the microbiological laboratory as nonpigmented, nonhemolytic, slow-growing pinpoint colonies after incubation on rabbit blood agar. In addition, the often relatively unstable SCVs demonstrate a number of other characteristics that are atypical for S. aureus including reduced alpha-toxin production and delayed coagulase activity. A site-directed hemB mutant with a stable SCV phenotype provided strong evidence for the link between these electron transport defective strains and persistent infections. The hemB mutant was phagocytized by cultured endothelial cells, but did not lyse these cells, because the mutant produced very little alpha-toxin. Thus, SCVs can hide within the host cell, then revert to the highly virulent rapidly growing form and lyse the host cell, once the host immune response has abated and antibiotic therapy is completed. The intracellular position shields SCVs from host defenses and decreases exposure to antibiotics. This review discusses what is known of the biology of SCVs and describes the recovery and significance of Staphylococcus SCVs in clinical specimen.

Animals↗
PubMed2000

Staphylococcus aureus small colony variants: formation and clinical impact.

S. aureus small-colony variants are a naturally occurring subpopulation which grow slowly and produce small colonies on routine media. They also demonstrate a number of other characteristics that are atypical for S. aureus including reduced alpha-toxin production and delayed coagulase activity. The connection of S. aureus SCVs with persistent and relapsing infections has been defined over the past decade, especially in patients with chronic osteomyelitis and in cystic fibrosis patients as demonstrated by prospective studies. While the studies with clinical isolates of SCVs suggested a link between electron transport-defective strains and persistent infections, a defined hemB mutant with the SCV phenotype provided strong additional evidence for these connections. The hemB mutant was phagocytosed by cultured endothelial cells, but did not lyse these cells, because the mutant produced very little alpha-toxin. The intracellular location may shield the SCVs from host defenses and antibiotics, thus providing one explanation for the difficulty in clearing S. aureus SCVs from host tissues.

Colony Count, Microbial↗
PubMed1999

Reconstructive treatment of sclerosing osteomyelitis of the entire femur of 30 years' duration with avoidance of segmental resection.

We describe the successful operative treatment of a patient with chronic sclerosing osteomyelitis of the femur in which en bloc resection was avoided. Therapy consisted of combined endoscopic, computed tomography and bone scan-guided fenestration and intramedullary reaming, with removal of all sclerotic zones and normalization of the cortical thickness. An adequate supply of oxygen to the area was ensured by improved vascularisation and the application of hydrogen peroxide. At the medium term follow-up no recurrence was seen, and hip and knee function was normal.

Bone Cements↗
PubMed1999

New aspects in the molecular basis of polymer-associated infections due to staphylococci.

Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, cause the majority of infections associated with both temporarily inserted and permanently implanted foreign bodies. In recent years, the pathogenesis of polymer-associated staphylococcal infection has become better understood, due in part to the characterization of further associated factors. The bacterial factors involved in the two phases of biofilm formation, i.e. the rapid adherence of bacteria to the polymer surface and the subsequent, more prolonged, accumulation phase, are presented in this review. The biofilm present on infected devices plays an important role in the pathogenicity of the infecting organism by protecting the embedded staphylococci and reducing the efficacy of host defenses and antimicrobial killing.

Bacterial Adhesion↗
PubMed1999

Bloodstream infections caused by small-colony variants of coagulase-negative staphylococci following pacemaker implantation.

Small-colony variants (SCVs) of Staphylococcus aureus cause persistent and relapsing infections. Relatively little is known regarding infections caused by SCVs of coagulase-negative staphylococci. We report two cases of pacemaker electrode infections due to SCVs of Staphylococcus epidermidis and Staphylococcus capitis. Sequence analysis of a portion of the 16S rRNA gene (16S rDNA) confirmed the identity of the staphylococcal species as S. capitis and S. epidermidis. Isolates from cultures of blood obtained over at least a 2-week interval were compared by pulsed-field gel electrophoresis and found to be clonal even though the colony morphology was very different. Analysis for auxotrophism revealed hemin dependencies for all isolated SCVs. The two cases have several clinical and laboratory characteristics (which are also seen with S. aureus SCV infections) and strongly suggest that SCVs of coagulase-negative staphylococci must be actively sought, because they grow very slowly and can be easily missed.

Bacteremia↗