The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the patho...The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.展开更多
Background: Coagulase negative Staphylococci (CoNS) positive blood cultures represent a complex and common challenge in clinical medicine. CoNS are common in skin flora and are often mistaken as contamination. Convers...Background: Coagulase negative Staphylococci (CoNS) positive blood cultures represent a complex and common challenge in clinical medicine. CoNS are common in skin flora and are often mistaken as contamination. Conversely, CoNS can also be implicated in severe and life-threatening bacteremia requiring prompt treatment. A gray area in terms of treatment approach exists for health care providers. The primary aim of this study was to examine predictive factors in patients who have positive CoNS blood cultures that met the CDC case definition of a laboratory confirmed bloodstream infection (LCBI-II) that were subsequently found to have clinically significant true bacteremia. Methods: A retrospective cohort of 288 patients that had at least two separate blood cultures positive for a coagulase negative Staphylococci between November 1st, 2017, and November 1st, 2018, were examined to determine if there were any patient specific factors that would indicate a true bacteremia with CoNS. Results: Retrospective regression analysis demonstrated that those subjected to antibiotics for two days or more (OR = 3.01), those subjected to antibiotics for seven days or more (OR = 2.86), and patients with central access (OR = 4.06) were more likely to have a true infection. Although not statistically significant, an association was also found in immunosuppressed patients (OR = 1.65), and in patients with implanted hardware (OR = 1.16). Conclusion: Patients receiving antibiotics for greater than two days and patients with a central line were more likely to have a true bloodstream infection with coagulase negative Staphylococci.展开更多
Background:Currently,coagulase negative staphylococci(CoNS)have got much attention as a serious health problem especially in neonates and children.High incidence of antibiotic resistance,in particular methicillin resi...Background:Currently,coagulase negative staphylococci(CoNS)have got much attention as a serious health problem especially in neonates and children.High incidence of antibiotic resistance,in particular methicillin resistance,has complicated the treatment of these organisms.The aim of this study is to determine the susceptibility to different antimicrobial agents and the prevalence of macrolides-lincosamides-streptogramins B(MLS_(B))resistance in CoNS isolates obtained from pediatric patients.Methods:Totally 157 CoNS isolates from various clinical samples were examined for antibiotic resistance using disk diffusion and E-test methods.Double-disk test was applied to detect constitutive and inducible MLSB resistance(cMLS_(B)and iMLS_(B))phenotypes.Results:Resistance to methicillin was seen in 98(62.4%)isolates.All isolates were susceptible to vancomycin and linezolid.The prevalence of resistance to antibiotics tested was as follows:fusidic acid(n=58,36.9%),gentamicin(n=73,46.5%),ciprofloxacin(n=81,51.6%),clindamycin(n=112,71.3%),erythromycin(n=129,82.2%)and trimethoprim/sulfamethoxazole(n=133,84.7%).iMLS_(B)phenotype was seen in 14(8.9%)isolates,and 18(11.5%)and 98(62.4%)isolates showed MS and cMLS_(B)phenotypes,respectively.We observed that high overall antibiotic resistance rates were associated significantly with methicillin resistance.Conversely,iMLS_(B)phenotype was correlated neither with methicillin resistance nor with invasiveness.Conclusion:Given the similarity observed between the prevalence of iMLS_(B)and MS phenotypes,the performance of disk diffusion induction test is strongly recommended in our region.展开更多
Apart from the conventional factors, recent evidences have suggested that lumbar disc herniation (LDH) is also associated with microbes, which is completely ignored in the management of patients with disc prolapse and...Apart from the conventional factors, recent evidences have suggested that lumbar disc herniation (LDH) is also associated with microbes, which is completely ignored in the management of patients with disc prolapse and disc degeneration. Therefore, the present study was carried out to identify the different microorganisms in subjects with LDH. Subjects (n = 101) who were confirmed for LDH with Magnetic Resonance Imaging and undergoing lumbar discectomy, were recruited in this study. Standard protocols for disinfection of the skin and surgical instruments were adhered. Skin scrapings, muscle biopsies and portion of the inter-vertebral disc were transferred into individually labeled Robertson’s cooked meat enrichment broth for anaerobic identification. Remaining portions of the excised disc material and muscle biopsy were taken for aerobic identification. Anaerobic isolates were identified using Gram stain and catalase test while the species identification was done by RapID ANA II ID kit. Gram stain, catalase test, DNase test and coagulase tests were used for identification of aerobic bacteria. Study confirmed 6/101 disc cultures (6%) with positive anaerobes and 12 disc cultures with coagulase negative Staphylococci spp. Among the anaerobes, two disc cultures were identified as Propionibacterium acnes and one as Gemella morbillorum. Due to slow growth, other three anaerobic cultures were not confirmed. However, they resembled the colony morphology of Gram positive bacilli. None of the control samples (skin and muscles) had any positive growth. The present study adds to the literature confirming the role of microorganisms in LDH. Present study newly identified Gemella morbillorum in the intervertebral tissue in addition to the previously reported microorganisms associated with LDH.展开更多
Staphylococcus cohnii is not known to causes meningitis. We present a case of mennigitis due to this organism. We are highlighting this case not only for its rarity but rapidity of worsening also. This report indicate...Staphylococcus cohnii is not known to causes meningitis. We present a case of mennigitis due to this organism. We are highlighting this case not only for its rarity but rapidity of worsening also. This report indicates that Staphylococcus cohnii are not as innocuous as once thought to be and these organisms should not be disregarded as possible skin contaminants. Before labelling them as contaminants their possible association with disease should be ruled out.展开更多
文摘The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.
文摘Background: Coagulase negative Staphylococci (CoNS) positive blood cultures represent a complex and common challenge in clinical medicine. CoNS are common in skin flora and are often mistaken as contamination. Conversely, CoNS can also be implicated in severe and life-threatening bacteremia requiring prompt treatment. A gray area in terms of treatment approach exists for health care providers. The primary aim of this study was to examine predictive factors in patients who have positive CoNS blood cultures that met the CDC case definition of a laboratory confirmed bloodstream infection (LCBI-II) that were subsequently found to have clinically significant true bacteremia. Methods: A retrospective cohort of 288 patients that had at least two separate blood cultures positive for a coagulase negative Staphylococci between November 1st, 2017, and November 1st, 2018, were examined to determine if there were any patient specific factors that would indicate a true bacteremia with CoNS. Results: Retrospective regression analysis demonstrated that those subjected to antibiotics for two days or more (OR = 3.01), those subjected to antibiotics for seven days or more (OR = 2.86), and patients with central access (OR = 4.06) were more likely to have a true infection. Although not statistically significant, an association was also found in immunosuppressed patients (OR = 1.65), and in patients with implanted hardware (OR = 1.16). Conclusion: Patients receiving antibiotics for greater than two days and patients with a central line were more likely to have a true bloodstream infection with coagulase negative Staphylococci.
基金supported by Tabriz Research Center of Infectious and Tropical Diseases(grant 91/04)Tabriz University of Medical Sciences,Tabriz,Iran
文摘Background:Currently,coagulase negative staphylococci(CoNS)have got much attention as a serious health problem especially in neonates and children.High incidence of antibiotic resistance,in particular methicillin resistance,has complicated the treatment of these organisms.The aim of this study is to determine the susceptibility to different antimicrobial agents and the prevalence of macrolides-lincosamides-streptogramins B(MLS_(B))resistance in CoNS isolates obtained from pediatric patients.Methods:Totally 157 CoNS isolates from various clinical samples were examined for antibiotic resistance using disk diffusion and E-test methods.Double-disk test was applied to detect constitutive and inducible MLSB resistance(cMLS_(B)and iMLS_(B))phenotypes.Results:Resistance to methicillin was seen in 98(62.4%)isolates.All isolates were susceptible to vancomycin and linezolid.The prevalence of resistance to antibiotics tested was as follows:fusidic acid(n=58,36.9%),gentamicin(n=73,46.5%),ciprofloxacin(n=81,51.6%),clindamycin(n=112,71.3%),erythromycin(n=129,82.2%)and trimethoprim/sulfamethoxazole(n=133,84.7%).iMLS_(B)phenotype was seen in 14(8.9%)isolates,and 18(11.5%)and 98(62.4%)isolates showed MS and cMLS_(B)phenotypes,respectively.We observed that high overall antibiotic resistance rates were associated significantly with methicillin resistance.Conversely,iMLS_(B)phenotype was correlated neither with methicillin resistance nor with invasiveness.Conclusion:Given the similarity observed between the prevalence of iMLS_(B)and MS phenotypes,the performance of disk diffusion induction test is strongly recommended in our region.
文摘Apart from the conventional factors, recent evidences have suggested that lumbar disc herniation (LDH) is also associated with microbes, which is completely ignored in the management of patients with disc prolapse and disc degeneration. Therefore, the present study was carried out to identify the different microorganisms in subjects with LDH. Subjects (n = 101) who were confirmed for LDH with Magnetic Resonance Imaging and undergoing lumbar discectomy, were recruited in this study. Standard protocols for disinfection of the skin and surgical instruments were adhered. Skin scrapings, muscle biopsies and portion of the inter-vertebral disc were transferred into individually labeled Robertson’s cooked meat enrichment broth for anaerobic identification. Remaining portions of the excised disc material and muscle biopsy were taken for aerobic identification. Anaerobic isolates were identified using Gram stain and catalase test while the species identification was done by RapID ANA II ID kit. Gram stain, catalase test, DNase test and coagulase tests were used for identification of aerobic bacteria. Study confirmed 6/101 disc cultures (6%) with positive anaerobes and 12 disc cultures with coagulase negative Staphylococci spp. Among the anaerobes, two disc cultures were identified as Propionibacterium acnes and one as Gemella morbillorum. Due to slow growth, other three anaerobic cultures were not confirmed. However, they resembled the colony morphology of Gram positive bacilli. None of the control samples (skin and muscles) had any positive growth. The present study adds to the literature confirming the role of microorganisms in LDH. Present study newly identified Gemella morbillorum in the intervertebral tissue in addition to the previously reported microorganisms associated with LDH.
文摘Staphylococcus cohnii is not known to causes meningitis. We present a case of mennigitis due to this organism. We are highlighting this case not only for its rarity but rapidity of worsening also. This report indicates that Staphylococcus cohnii are not as innocuous as once thought to be and these organisms should not be disregarded as possible skin contaminants. Before labelling them as contaminants their possible association with disease should be ruled out.
