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PubMed1979

Identification of clumping-factor-negative staphylococci isolated from cows' udders.

Identification to species level was attempted on a collection of 954 cultures of catalase-positive, clumping-factor- and beta-haemolysin-negative Gram-positive cocci isolated from teats and milk of cows. Eighty-seven per cent of the strains were identified as Staphylococcus xylosus, S epidermidis, S sciuri, S haemolyticus, S hyicus subsp hyicus and chromogenes, S simulans and S cohnii. Nine per cent of the collection belonged to another group which could not be identified with any of the known Staphylococcus species. Many of the strains of this group and also part of the S epidermidis and S hyicus subsp chromogenes strains examined showed various degrees of growth enhancement on certain media when fatty substances were added. Only nine strains were classified as Micrococcus. A scheme for the identification of coagulase-negative staphylococci from cows' milk is proposed.

Animals↗

PubMed2002

Comparability of antimicrobial susceptibility test results from 22 European countries and Israel: an external quality assurance exercise of the European Antimicrobial Resistance Surveillance System (EARSS) in collaboration with the United Kingdom National External Quality Assurance Scheme (UK NEQAS).

The goal of this exercise was to organize external quality assurance (QA) of antibiotic susceptibility testing for laboratories participating in EARSS and to assess the comparability of susceptibility test results across countries, and guidelines. In September 2000, UK NEQAS distributed a set of three Streptococcus pneumoniae strains, two Staphylococcus aureus strains and one Streptococcus haemolyticus strain. Laboratories reported the guideline followed, the interpretation of the susceptibility test result and the MIC, if tested. In this study we considered results 'concordant' if the reported interpretation of the participating laboratory agreed with the designated interpretation of reference laboratories. Overall, 433 (92%) of 471 laboratories from 23 countries reported back. Of the 8685 tests that were assessed, 8322 (96%) were interpreted correctly by the participants. Concordance for detection of penicillin non-susceptibility in the three S. pneumoniae strains was 96%, 90% and 87%, respectively. Laboratories performed extremely well in detecting oxacillin resistance in the homogeneously methicillin-resistant S. aureus (MRSA) strain, but the concordance rate dropped from 100% to 77% in the heterogeneously resistant MRSA strain. Concordance for detection of teicoplanin resistance in the S. haemolyticus strain was 82%. We stratified concordance rates first for country and then for guideline used, but observed only minor differences among countries and guidelines. Quantitative methods yielding an MIC were more concordant than non-MIC methods for penicillin resistance in the S. pneumoniae strains (94% versus 79%). The NCCLS guideline was the most frequently followed, by 61% of laboratories from 19 countries. This exercise shows that, overall, countries participating in EARSS are capable of delivering susceptibility data of good quality. The comparability of susceptibility data for penicillin resistance in S. pneumoniae and for homogeneous methicillin resistance in S. aureus is satisfactory among European countries and across guidelines. However, we emphasize the importance of determining an MIC for suspected penicillin non-susceptible S. pneumoniae and for suspected glycopeptide non-susceptible S. aureus. Laboratories, particularly in some countries, may need to improve their capability to detect oxacillin resistance in heterogeneously resistant MRSA. For continuous external quality assessment we recommend that laboratories participate in national and international schemes with frequent distribution of control strains.

Drug Resistance, Bacterial↗

PubMed2002

Intravenous rifampicin in neonates with persistent staphylococcal bacteraemia.

UNLABELLED: Addition of intravenous rifampin is reported to be useful in prompt clearance of persistent coagulase negative staphylococcal (CONS) bacteraemia in high-risk neonates. Four neonates (mean birthweight 823 g, mean gestation 25 wk) with persistent CONS bacteraemia for > 7-10 d (mean 11) were treated with i.v. rifampicin (10 mg/kg/12 h x 10 d) while continuing vancomycin (15 mg/kg/24 h). Their age at time of infection ranged from 2 to 11 d. The mean (range) vancomycin peak and trough concentrations were 29 (25-35) and 6 (4-10) microg/ml, respectively. The blood isolates were Staphylococcus epidermidis, S. hominis, and S. haemolyticus. Addition of rifampicin was associated with prompt clearance of bacteraemia within 48 h (n = 3) and 5 d (n - 1). Rifampicin-related adverse effects such as abnormal liver function tests and thrombocytopenia did not occur. CONCLUSION: Addition of i.v. rifampicin to vancomycin may optimize the outcome of persistent CONS bacteraemia and the risk of bacterial resistance related to prolonged exposure to vancomycin.

Bacteremia↗

PubMed1988

A quantitative study of enterotoxin production by sheep milk staphylococci.

Of 124 staphylococcal strains isolated from sheep milk, 78 produced enterotoxin A, B, C, or D when evaluated by an enzyme-linked immunosorbent assay. Enterotoxins A and D, elaborated by 44 and 43 strains, respectively, showed the highest incidence. Enterotoxin production by coagulase-negative strains (one Staphylococcus cohnii, three S. epidermidis, five S. haemolyticus, and four S. xylosus) was detected. Linear and logarithmic-logarithmic regressions of optical density on enterotoxin concentration yielded the best-fitting equations for enterotoxin quantitation. A significantly higher incidence of enterotoxin producers and significantly higher levels of enterotoxins produced were recorded for coagulase-positive, thermostable nuclease-positive, hemolysis-positive, or mannitol-positive strains. Mannitol utilization was the best test for discriminating between enterotoxigenic and nonenterotoxigenic staphylococci.

Animals↗

PubMed2005

Comparison of methods for the identification of coagulase-negative staphylococci.

Coagulase-negative staphylococci (CNS) species identification is still difficult for most clinical laboratories. The scheme proposed by Kloos and Schleifer and modified by Bannerman is the reference method used for the identification of staphylococcal species and subspecies; however, this method is relatively laborious for routine use since it requires the utilization of a large number of biochemical tests. The objective of the present study was to compare four methods, i.e., the reference method, the API Staph system (bioMérieux) and two methods modified from the reference method in our laboratory (simplified method and disk method), in the identification of 100 CNS strains. Compared to the reference method, the simplified method and disk method correctly identified 100 and 99% of the CNS species, respectively, while this rate was 84% for the API Staph system. Inaccurate identification by the API Staph method was observed for Staphylococcus epidermidis (2.2%), S. hominis (25%), S. haemolyticus (37.5%), and S. warneri (47.1%). The simplified method using the simple identification scheme proposed in the present study was found to be efficient for all strains tested, with 100% sensitivity and specificity and proved to be available alternative for the identification of staphylococci, offering, higher reliability and lower cost than the currently available commercial systems. This method would be very useful in clinical microbiology laboratory, especially in places with limited resources.

Bacterial Typing Techniques↗

PubMed1985

Identification of coagulase-negative staphylococci from farm animals.

The species identify of 661 strains of coagulase-negative staphylococci isolated from the skin and nares of cattle, pigs, poultry, goats and sheep was determined. They belonged either to the novobiocin-sensitive species Staphylococcus hyicus, Staph. simulans, Staph. epidermidis, Staph. haemolyticus and Staph. warneri or to the novobiocin-resistant species Staph. sciuri, Staph. lentus, Staph. xylosus, Staph. cohnii, Staph. saprophyticus and Staph. gallinarum; twenty-one strains remained unidentified. The staphylococcal flora of the farm animals studied differed markedly from that associated with man; several species which do not occur in man were isolated and novobiocin-resistant strains, which occur infrequently in man, were present in large numbers in animals. Two simplified schemes for the identification of staphylococci from farm animals and man are presented.

Animals↗

PubMed2003

Decreased vancomycin susceptibility of coagulase-negative staphylococci in a neonatal intensive care unit: evidence of spread of Staphylococcus warneri.

Coagulase-negative staphylococci (CoNS) are important pathogens in premature neonates; decreasing glycopeptide susceptibility has been observed among these isolates. The epidemiology of colonization with CoNS, the organisms' vancomycin susceptibilities, and genetic relatedness were studied over 6 months in a tertiary-care neonatal unit. A total of 321 isolates of CoNS were isolated. Seventy-five percent of the infants were colonized at admission, and virtually all were colonized thereafter. Common species were Staphylococcus epidermidis (69%), S. warneri (12%), S. haemolyticus (9.7%), and S. hominis (5.6%). A total of 3.9% of CoNS isolates had decreased vancomycin susceptibility (DVS) (MICs > 2.0 microg/ml); isolate recovery was associated with a stay in a neonatal intensive care unit for >28 days (P = 0.039), vancomycin exposure (P = 0.021), and S. warneri colonization (P < 0.0001). Nine of 12 (75%) CoNS with DVS were S. warneri, had enhanceable high-level resistance in vitro, were indistinguishable or closely related by pulsed-field gel electrophoresis, and were different from 29 vancomycin-susceptible S. warneri isolates. Epidemiological analysis suggested unsuspected nosocomial spread. Species determination in certain settings may aid in the understanding of emerging nosocomial problems.

Anti-Bacterial Agents↗

PubMed2001

Evaluation of a latex agglutination test (MRSA-Screen) for detection of oxacillin resistance in coagulase-negative Staphylococci.

The MRSA-Screen (Denka-Seiken, Tokyo, Japan) latex agglutination test was evaluated for its ability to detect PBP 2a from 200 clinical isolates of coagulase-negative staphylococci (CoNS; 84 mecA-positive strains and 116 mecA-negative strains) consisting of 108 Staphylococcus epidermidis, 37 S. saprophyticus, 15 S. haemolyticus, 11 S. hominis, 10 S. capitis, 10 S. warneri, and 3 S. lugdunensis species as well as 6 other species of CoNS. The assay was compared with susceptibility testing with an agar screen plate with oxacillin at 6 microg/ml (OXA6), by oxacillin disk diffusion (DD), by broth microdilution (BMDIL), by the E test, and with Vitek GPS-SV and Vitek GPS-107 susceptibility cards. PCR for the detection of the mecA gene was used as the "gold standard." The sensitivities and specificities for the methods evaluated were as follows: MRSA-Screen, 100 and 100%, respectively; OXA6, 100 and 99%, respectively; DD, 98 and 62%, respectively; BMDIL, 100 and 60%, respectively; E test, 100 and 51%, respectively; Vitek GPS-SV susceptibility card, 98 and 87%, respectively; and Vitek GPS-107 susceptibility card, 100 and 61%, respectively. The MRSA-Screen test accurately and rapidly detected oxacillin resistance in CoNS.

Bacterial Proteins↗

PubMed1979

Factors causing the clumping reaction of streptococcal strains with human plasma.

Fresh isolates of 204 strains of Streptococcus haemolyticus, 75 strains of viridans group Streptococcus, and 45 strains of Streptococcus pneumoniae were studied for their clumping reactions with human plasma. The plasma and serum factors that clumped the streptococcal strains were compared with those that clumped a Staphylococcus aureus strain. One hundred eleven strains of S. haemolyticus, 10 strains of viridans group Streptococcus, and none of the strains of S. pneumoniae tested were clumped by human plasma. However, clumping activity was remarkably unstable after subculturing on plates containing Todd-Hewitt blood agar. The strain with the highest level of activity was clumped by fibrinogen and normal human serum. Results of tests of the clumping reactions of staphylococci and streptococci with human serum indicated that the serum factors responsible for those reactions may be identical.

Bacteriological Techniques↗

PubMed2006

Tabebuia avellanedae naphthoquinones: activity against methicillin-resistant staphylococcal strains, cytotoxic activity and in vivo dermal irritability analysis.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococcus infections are a worldwide concern. Currently, these isolates have also shown resistance to vancomycin, the last therapy used in these cases. It has been observed that quinones and other related compounds exhibit antibacterial activity. This study evaluated the antibacterial activity, toxicity and in vivo dermal irritability of lapachol extracted from Tabebuia avellanedae and derivatives against methicillin-resistant staphylococcal isolates. In addition, its mechanism of action was also analyzed. METHODS: The compounds beta-lapachone, 3-hydroxy beta N lapachone and alpha-lapachone were tested to determine the MIC values against methicillin-resistant S. aureus, S. epidermidis and S. haemolyticus strains, being the two last ones hetero-resistant to vancomycin. Experiments of protein synthesis analysis to investigate the naphthoquinones action were assessed. In vitro toxicity to eukaryotic BSC-40 African Green Monkey Kidney cell cultures and in vivo primary dermal irritability in healthy rabbits were also performed. RESULTS: The compounds tested showed antibacterial activity (MICs of 8, 4/8 and 64/128 microg/mL to beta-lapachone, 3-hydroxy beta N lapachone and alpha-lapachone, respectively), but no bactericidal activity was observed (MBC > 512 microg/mL for all compounds). Although it has been observed toxic effect in eukaryotic cells, the compounds were shown to be atoxic when applied as topic preparations in healthy rabbits. No inhibition of proteins synthesis was observed. CONCLUSION: Our results suggest that quinones could be used in topic preparations against wound infections caused by staphylococci, after major investigation of the pharmacological properties of the compounds. Studies about the use of these compounds on tumoral cells could be carried on, due to their effect in eukaryotic cells metabolism.

Animals↗

PubMed1978

Species identification of coagulase-negative staphylococci from urinary tract isolates.

A new scheme for identification of coagulase-negative staphylococci was applied to 138 consecutive urinary isolates of coagulase-negative staphylococci. The most common species were Staphylococcus epidermidis (53%), S. hominis (12%), and S. haemolyticus (10%). S. saprophyticus comprised only 5%. The disk method for antibiotic susceptibility for all species grouped together disclosed resistance most commonly to penicillin (35%), tetracycline (33%), methicillin (27%), and sulfonamide (24%). This pattern was also seen specifically with S. epidermidis. Further studies are needed to determine the incidence of species-specific antibiotic resistance and species-specific infection by site. This may be of particular interest in those patients with nosocomial infections due to coagulase-negative staphylococci.

Anti-Bacterial Agents↗

PubMed1994

[Activity of ofloxacin and other fluoroquinolones against staphylococcus which is either resistant to or susceptible to methicillin].

The activity of 37 antibiotics against 155 strains of Staphylococcus susceptible to methicillin (MS) and 107 strains of Staphylococcus resistant to methicillin (MR) was evaluated. Only vancomycin and teicoplanin remained active in relation to all the studied Staphylococcus strains. A high activity also was demonstrated by netilmicin (99.57%) and quinolones (more than 90%). The percentage of strains resistant to aminoglycoside, linkosamide, fluoroquinolones and other antibiotics was found to be higher within MR strains than in MS strains. All strains resistant to rifampin belonged to the MR Staphylococcus group. Among the 6 studied fluoroquinolones ofloxacin (97.71%) was found to be the most active. Three Staphylococcus aureus strains (MICOFX 16 micrograms/ml), one S-haemolyticus strain and one S. epidermidis strain (MICOFX 8 micrograms/ml) were the most resistant.

Anti-Infective Agents↗

PubMed1996

HSP60 gene sequences as universal targets for microbial species identification: studies with coagulase-negative staphylococci.

A set of universal degenerate primers which amplified, by PCR, a 600-bp oligomer encoding a portion of the 60-kDa heat shock protein (HSP60) of both Staphylococcus aureus and Staphylococcus epidermidis were developed. However, when used as a DNA probe, the 600-bp PCR product generated from S. epidermidis failed to cross-hybridize under high-stringency conditions with the genomic DNA of S. aureus and vice versa. To investigate whether species-specific sequences might exist within the highly conserved HSP60 genes among different staphylococci, digoxigenin-labelled HSP60 probes generated by the degenerate HSP60 primers were prepared from the six most commonly isolated Staphylococcus species (S. aureus 8325-4, S. epidermidis 9759, S. haemolyticus ATCC 29970, S. schleiferi ATCC 43808, S. saprophyticus KL122, and S. lugdunensis CRSN 850412). These probes were used for dot blot hybridization with genomic DNA of 58 reference and clinical isolates of Staphylococcus and non-Staphylococcus species. These six Staphylococcus species HSP60 probes correctly identified the entire set of staphylococcal isolates. The species specificity of these HSP60 probes was further demonstrated by dot blot hybridization with PCR-amplified DNA from mixed cultures of different Staphylococcus species and by the partial DNA sequences of these probes. In addition, sequence homology searches of the NCBI BLAST databases with these partial HSP60 DNA sequences yielded the highest matching scores for both S. epidermidis and S. aureus with the corresponding species-specified probes. Finally, the HSP60 degenerate primers were shown to amplify an anticipated 600-bp PCR product from all 29 Staphylococcus species and from all but 2 of 30 other microbial species, including various gram-positive and gram-negative bacteria, mycobacteria, and fungi. These preliminary data suggest the presence of species-specific sequence variation within the highly conserved HSP60 genes of staphylococci. Further work is required to determine whether these degenerate HSP60 primers may be exploited for species-specific microbic identification and phylogenetic investigation of staphylococci and perhaps other microorganisms in general.

Base Sequence↗

PubMed1992

On the relationship between theoretical presumptions asbestos genotoxicity and the practical monitoring of exposed workers.

From the genotoxic viewpoint, there exists a sufficient evidence for asbestos carcinogenicity to human population and animals. Asbestos is a solid cancer promoter (cocarcinogen) of non-mutagenic character having epigenetic effects (15, 16). No data have been published on its mutagenic activity in "in vivo" conditions in man. The only results are those of our pilot study carried out in the period of 1981-1983, which cast doubts on the official view of non-mutagenic character of asbestos--at least under occupational conditions of its processing (34, 36, 37). The study presented here represents ten years' efforts made in the biological (cytogenetic) monitoring of persons occupationally exposed to asbestos in a factory for its processing (occupational risk). Simultaneously, a preliminary answer is given to the question whether the Osinek factory (situated in a housing area) is or is not dangerous for inhabitants of the town of Kostelec nad Orlicí, namely for their genetic apparatus (environmental risk). Using the method of chromosome aberrations analysis in peripheral blood lymphocytes, a total of 431 subjects (245 males and 186 females) were examined in the period of 1981 to 1988. Of these, 111 persons were from control workplaces (from Osinek or--starting from 1984--from other plants in Kostelec nad Orlicí; in addition to that 14 pensioners without any occupational exposure were examined). The average age of workers exposed to asbestos risk was 42.7 years, in the controls it was 43.9 years, in pensioners exposed to asbestos earlier 63.5 years and in those never exposed to asbestos 66.5 years. The average number of years spent at Osinek factory amounted to 21.5 years. About one third of employees were found to suffer from allergies (first of all those of air passages) and one sixth from chronic ailments of the upper air passages (Staphylococcus aureus, Haemophilus influenzae and Streptococcus beta-haemolyticus were diagnosed most frequently). A third part of workers from high-risk workshops are smokers, only a fourth of the controls. About 40% of workers regularly consume alcoholic drinks. The average morbidity rate at Osinek in 1981 to 1988 was 6.3% (in workers as high as 9%), which is about 2% higher as compared with mean values obtained in the district of Rychnov nad Knĕznou and East-Bohemian region. Within the nine-year period (1981-1989), 21 occupational diseases were diagnosed, while in the previous 24 years there were 24 cases of an occupational disease. Earlier they were mainly asbestoses (87%), in the last period mainly cancer diseases coinciding with asbestosis (81%).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed2001

Comparative in vitro study of pulp capping materials.

AIM: In a comparative in vitro study we examined the bactericidal effect, adhesion and shrinkage of 5% potassium nitrate in Carboxy-Adhaesor, 5% potassium chloride in Carboxy-Adhaesor, Carboxy-Adhaesor, Adhaesor and Dycal. MATERIAL AND METHODS: The bactericidal effect of the investigated pulp capping materials on the isolated microorganisms Staphylococcus aureus, Staph. epidermidis, Streptococcus viridans alpha-haemolyticus, Streptococcus pneumoniae and Streptococcus beta-haemolyticus was assessed by the diffusion method around each disk in mm. The adhesion and shrinkage were assessed after hardening of the material. RESULTS: The results obtained showed higher bactericidal activity of polycarboxylate cements in comparison to Adhaesor and Dycal. The largest zone of inhibition was found around the disks with polyacrilic acid, followed by 5% KNO3 in polyacrilic acid, 5% KCl in polyacrilic acid; significantly smaller is the zone around Dycal. The difference was statistically significant (p<0.01). The adhesion and shrinkage of polycarboxylate cements were estimated as very good, better than those of Adhaesor and Dycal. CONCLUSION: The bactericidal effect of 5% KNO3 in polycarboxylate cement is very good for the microorganisms isolated from deep caries. The adhesion to hard tissues is very good, which suggests good marginal adaptation to the cavity.

Anti-Bacterial Agents↗

PubMed1998

Antibiotic resistance genes in coagulase-negative staphylococci isolated from food.

Coagulase-negative staphylococci were isolated from different raw milk cheeses and raw meat products and screened for their antibiotic resistances. They were identified as Staphylococcus xylosus, S. lentus, S. caprae, S. epidemidis and S. haemolyticus. The most frequent resistances found were those to chloramphenicol, tetracycline, erythromycin and lincomycin. They have been characterized on the molecular level. The chloramphenicol resistance genes were localized in several S. xylosus and S. caprae on plasmids with sizes ranging from 3.8-kb to 4.3-kb and were identified as chloramphenicol acetyltransferase (cat). All the tetracycline resistant strains were identified as S. xylosus and harboured a 4.4-kb plasmid carrying the tetracycline efflux resistance gene (tetK). The two erythromycin/lincomycin resistant S. caprae and S. epidermidis strains did not hybridize with the MLSB resistance genes ermAM, ermA, ermB and ermC. Three erythromycin resistant Staphylococcus sp. strains harboured an erythromycin efflux resistance gene (msr) localized twice on a 18-kb plasmid and once on the chromosome. A S. haemolyticus strain showing resistance to both lincomycin and clindamycin harboured a linA gene-carrying 2.2-kb plasmid. Further resistances to gentamicin, penicillin and kanamycin were less frequently observed and yet not characterized on a molecular level.

Animals↗

PubMed2001

Development of a PCR assay for identification of staphylococci at genus and species levels.

We have developed a PCR-based assay which allows the detection of staphylococci at the genus level by targeting the tuf gene, which encodes the elongation factor Tu. Degenerate PCR primers derived from consensus regions of several tuf genes were used to amplify a target region of 884 bp from 11 representative staphylococcal species. Subsequently, the entire nucleotide sequence of these amplicons was determined. The analysis of a multiple alignment of these sequences revealed regions conserved among staphylococci but distinct from those of other gram-positive bacteria genetically related to staphylococci. PCR primers complementary to these regions could amplify specifically and efficiently a DNA fragment of 370 bp for all of 27 different staphylococcal species tested. There was no amplification with genomic DNA prepared from 53 nonstaphylococcal species tested to verify the specificity of the assay (20 gram positive and 33 gram negative). Furthermore, this assay amplified efficiently all 27 American Type Culture Collection (ATCC) staphylococcal reference strains as well as 307 clinical isolates of staphylococci from the Québec City region. Analysis of the multiple sequence alignment for the 884-bp fragment for the 11 staphylococcal species as well as comparison of the sequences for the 370-bp amplicon from five unrelated ATCC and clinical strains for each of the species S. aureus, S. epidermidis, S. haemolyticus, S. hominis, and S. saprophyticus demonstrated sufficient interspecies polymorphism to generate genus- and species-specific capture probes. This sequence information allowed the development of Staphylococcus-specific and species-specific (targeting S. aureus, S. epidermidis, S. haemolyticus, S. hominis, or S. saprophyticus) capture probes hybridizing to the 370-bp amplicon. In conclusion, this PCR assay is suitable for detection of staphylococci at both genus and species levels.

DNA Primers↗

PubMed1986

Microbiologic studies of coagulase-negative staphylococci isolated from patients with nosocomial bacteraemias.

We studied 50 strains of coagulase-negative staphylococci (CNS) isolated from 50 patients with hospital-acquired bacteraemia, identified by prospective surveillance at the University of Virginia Hospital between March 1981 and September 1982. Using the Staph-Ident System for speciation, we found that 37 strains (74%) were Staphylococcus epidermidis, 7 (14%) Staph. hominis, 3 (6%) Staph. haemolyticus and 3 (6%) Staph. warneri. 33 (66%) of the strains produced slime and a higher proportion of the Staph. epidermidis group (75%) than the non-epidermidis group (46%), did so. Minimal inhibitory concentrations (MIC) were determined by a microdilution technique with 20 different antibiotics. There was no difference in geometric mean MICs between slime producers and non-slime producers within either the epidermidis or non-epidermidis group. The most potent antibiotics against Staph. epidermidis (MIC90 mg l-1) were rifampin (0.05), netilmicin (0.05), amikacin (2.9), thienamycin (0.75), teichomycin (0.85), vancomycin (1.0) and nafcillin (0.39). On the other hand strains were resistant to tobramycin (15), moxalactam (50), fosfomycin (greater than 64), and clindamycin (greater than 64). Overall, eight (16%) of the CNS strains were resistant to methicillin, three of which were Staph. haemolyticus. The non-epidermidis strains were more resistant than the Staph. epidermidis strains to most beta-lactam antibiotics. Differences in antibiograms indicate that speciation of CNS may prove useful for clinical and epidemiologic purposes.

Anti-Bacterial Agents↗