ABSTRACT
OBJECTIVES: A retrospective study was conducted in the Bone Marrow Transplant Center of Tunisia during a period of 10 years (from 2002 to 2011) in order to report the prevalence of infectious multi-drug resistant bacteria. METHODS: Bacterial identification was carried on the basis of biochemical characteristics and API identification systems. Antibiotic susceptibility was tested by disc diffusion method on Muller-Hinton agar. RESULTS: During the study period, 34.5% of 142 Klebsiella pneumoniae strains and 11.46% of 218 Escherichia coli strains were extended-spectrum beta-lactamase (ESBL) producers. Also, 32.8% of 210 strains of Pseudomonas aeruginosa were imipenem and/or ceftazidime resistant and 20.75% of 106 strains of Staphylococcus aureus were methicillin resistant. A rising trend was observed for the prevalence of the selected multidrug resistant bacteria. CONCLUSION: These findings may have important clinical implications in prophylaxis and selection of antibiotic treatment. Continuous surveillance is needed, especially for onco-hematological patients.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Drug Resistance, Multiple, Bacterial , Immunocompromised Host , Stem Cell Transplantation , Escherichia coli/drug effects , Escherichia coli/isolation & purification , Humans , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Microbial Sensitivity Tests , Prevalence , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/isolation & purification , Retrospective Studies , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Tunisia/epidemiologyABSTRACT
BACKGROUND: We investigated the diversity of the primary sequences of the 16S rRNA genes among 46 commensal Neisseria strains and evaluated the use of this approach as a molecular typing tool in comparison with PFGE analysis. METHODS: Identification to the genus was done using conventional methods and API NH (bio-Mérieux® ). Identification to species level was based on 16S rRNA gene sequencing. PFGE analysis was done using SpeI. RESULTS: Fourteen, two, three and fourteen 16S rRNA sequence types were found among twenty Neisseria flavescens, two Neisseria sicca, five Neisseria macacae and nineteen Neisseria mucosa clinical isolates. Forty-three different PFGE patterns were found among the tested strains. CONCLUSION: We demonstrated a high diversity among 16S rRNA genes which was reflected by PFGE analysis.
Subject(s)
Molecular Typing/methods , Neisseria/genetics , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Genotyping Techniques , Humans , Neisseria/classification , Neisseriaceae Infections/microbiology , Polymerase Chain Reaction , Sequence Analysis, DNAABSTRACT
We analyzed 85 Neisseria spp. strains collected by swabbing from neutropenic patients to determine the prevalence of reduced susceptibility to penicillin and to ascertain the clonal relationship between these strains. High genetic diversity and an elevated level of penicillin resistance were found among commensal Neisseria clinical isolates.
Subject(s)
Drug Tolerance , Neisseria/classification , Neisseria/drug effects , Penicillins/pharmacology , Genetic Variation , Genotype , Genotyping Techniques , Humans , Neisseria/genetics , Neisseria/isolation & purification , Neisseriaceae Infections/microbiology , PrevalenceABSTRACT
We aimed to compare accuracy of genus and species level identification of Neisseria spp. using biochemical testing and 16S rRNA sequence analysis. These methods were evaluated using 85 Neisseria spp. clinical isolates initially identified to the genus level by conventional biochemical tests and API NH system (Bio-Mérieux(®)). In 34 % (29/85), more than one possibility was given by 16S rRNA sequence analysis. In 6 % (5/85), one of the possibilities offered by 16S rRNA gene sequencing, agreed with the result given by biochemical testing. In 4 % (3/85), the same species was given by both methods. 16S rRNA gene sequencing results did not correlate well with biochemical tests.
Subject(s)
Bacterial Typing Techniques/methods , Gram-Negative Bacterial Infections/microbiology , Neisseria/classification , Neisseria/isolation & purification , Neisseria/genetics , RNA, Bacterial/analysis , RNA, Ribosomal, 16S/analysis , Reproducibility of Results , Sensitivity and Specificity , Sequence Analysis, RNA/methodsABSTRACT
Neisseria mucosa, a Gram-negative diplococcus, is part of normal nasopharyngeal flora. We report a case of bacteremia caused by N. mucosa in a 50-year-old neutropenic patient suffering from non-secretory multiple myeloma stage IIIA. This case underscores that mostly nonpathogenic N. mucosa can cause bacteremia in neutropenic patients who developed mucositis after hematopoietic stem cell transplantation.
Subject(s)
Bacteremia/etiology , Neisseria mucosa/pathogenicity , Neisseriaceae Infections/etiology , Bacteremia/microbiology , Female , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunocompromised Host , Middle Aged , Multiple Myeloma/complications , Multiple Myeloma/therapy , Neisseria mucosa/classification , Neisseria mucosa/genetics , Neisseriaceae Infections/microbiology , Neutropenia/complicationsABSTRACT
In the present work, nearly the entire 16S rRNA gene sequences of 46 clinical samples of Neisseria spp. were determined, and the aligned sequences were analyzed to investigate the diversity of 16S rRNA genes in each commensal Neisseria species. Two 16S rRNA types were identified in two Neisseria sicca strains, three 16S rRNA types in five Neisseria macacae strains, fourteen 16S rRNA types in twenty Neisseria flavescens isolates, and fourteen 16S rRNA types in nineteen Neisseria mucosa isolates. The number of nucleotides that were different between 16S rRNA sequences within specie ranged from 1 to 15. We found high intraspecific sequence variation in 16S rRNA genes of Neisseria spp. strains.
Subject(s)
Genetic Variation , Neisseria/genetics , RNA, Ribosomal, 16S/genetics , Amino Acid Sequence , Bacterial Typing Techniques , Molecular Sequence Data , Neisseria/classification , Neisseria/isolation & purification , Phylogeny , Polymerase Chain Reaction , RNA, Bacterial/genetics , Sequence Analysis, DNAABSTRACT
Multilocus sequence typing and pulsed-field gel electrophoresis were used to type 22 commensal isolates of Neisseria perflava collected by swabbing from neutropenic patients. High genetic diversity was found among our N. perflava clinical isolates.
