Subject(s)
Corynebacterium Infections/microbiology , Corynebacterium/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Bacteriological Techniques , Corynebacterium/genetics , Corynebacterium Infections/diagnosis , DNA, Bacterial/chemistry , DNA-Directed RNA Polymerases/chemistry , DNA-Directed RNA Polymerases/genetics , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , HumansABSTRACT
Since the Arab Spring, a resurgence of zoonotic diseases such as rickettsiosis, endemic in the Mediterranean basin, has been observed. It preferentially infects microvascular endothelial cells of mammalian hosts inducing vasculitis with endothelial injury. Rickettsioses are considered benign infectious diseases. Severe systemic manifestations have been reported and are often explained by a delay in diagnosis. We present a case of hemophagocytic syndrome occurring in a 4-year-old Libyan girl as a complication of Mediterranean spotted fever. Rickettsial infection was confirmed by serology and the patient was treated with clarithromycin, with a favorable outcome.
Subject(s)
Boutonneuse Fever/complications , Macrophage Activation Syndrome/microbiology , Rickettsia conorii , Child, Preschool , Female , HumansABSTRACT
We evaluated the Bruker Biotyper matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) for the identification of 97 Corynebacterium clinical in comparison to identification strains by Api Coryne and MALDI-TOF-MS using 16S rRNA gene and hypervariable region of rpoB genes sequencing as a reference method. C. striatum was the predominant species isolated followed by C. amycolatum. There was an agreement between Api Coryne strips and MALDI-TOF-MS identification in 88.65% of cases. MALDI-TOF-MS was unable to differentiate C. aurimucosum from C. minutissimum and C. minutissimum from C. singulare but reliably identify 92 of 97 (94.84%) strains. Two strains remained incompletely identified to the species level by MALDI-TOF-MS and molecular approaches. They belonged to Cellulomonas and Pseudoclavibacter genus. In conclusion, MALDI-TOF-MS is a rapid and reliable method for the identification of Corynebacterium species. However, some limits have been noted and have to be resolved by the application of molecular methods.
Subject(s)
Bacterial Typing Techniques/methods , Corynebacterium/classification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Bacterial Proteins/genetics , Cellulomonas/classification , Cellulomonas/genetics , Cellulomonas/isolation & purification , Corynebacterium/genetics , Corynebacterium/isolation & purification , Corynebacterium Infections/microbiology , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , DNA-Directed RNA Polymerases/genetics , Humans , Micrococcaceae/classification , Micrococcaceae/genetics , Micrococcaceae/isolation & purification , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Reagent Strips , RibotypingABSTRACT
OBJECTIVES: Extended-spectrum ß-lactamases are widespread in hospital settings worldwide. The prevalence of ESBL producing Klebsiella pneumoniae (ESBL-KP) strains isolated from patients has recently increased in Tunisia. We conducted this study to determine the prevalence and the genetic characterization of ESBL-KP in a Tunisian Hospital. PATIENTS AND METHODS: We performed antibiotic susceptibility testing, multiplex PCR, and DNA sequencing analysis on 118 non repetitive K. pneumonia strains isolated during three years, to determine the prevalence and genotypes of ESBL among K. pneumoniae clinical isolates. RESULTS: Most ESBL-producing K. pneumonia strains were isolated from hospitalized patients, especially in neonatal and pediatric wards. The resistance to other antibiotics was high. Most of the pathogens were isolated from the urinary tract (86.44%). Carbapenems were the most effective antimicrobial agents followed by amikacin and fosfomycin. The rate of blaSHV, blaTEM, and blaCTX-M genes among the isolates was 89, 56.78, and 81.35%, respectively. Sequencing revealed the amplicons encoding TEM-1, TEM-53, TEM-158, SHV-1, SHV-11, SHV-28, CTX-M-15, CTX-M-15-like. The blaCTX-M-15 was the dominant gene among Tunisian isolates, but this was the first report of blaTEM-53 and blaTEM-158 genes in the country. CONCLUSIONS: Our results confirm the predominance of CTX-M-15 in Tunisia. To our knowledge, this is the first report of TEM-158 and TEM-53 in Tunisia.
Subject(s)
Bacterial Proteins/isolation & purification , Cross Infection/microbiology , Klebsiella Infections/microbiology , Klebsiella pneumoniae/enzymology , beta-Lactam Resistance/genetics , beta-Lactamases/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Proteins/classification , Bacterial Proteins/genetics , Child , Child, Preschool , Cross Infection/epidemiology , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Female , Genes, Bacterial , Genotype , Hospital Departments , Hospitals, University , Humans , Infant , Infant, Newborn , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/drug effects , Male , Middle Aged , Multiplex Polymerase Chain Reaction , Species Specificity , Tunisia/epidemiology , Young Adult , beta-Lactamases/classification , beta-Lactamases/geneticsABSTRACT
OBJECTIVE: We determined the macrolide resistance phenotypes and genotypes in Streptococcus pneumoniae isolates in Sousse and assessed the serotype distribution. METHODS: We included S. pneumoniae strains isolated at our laboratory (2010-2013). The antimicrobial susceptibility was tested according to CA-SFM specifications. Serotyping was performed by agglutination of latex particles, to identify a subset of serotypes included in pneumococcal conjugate vaccines. The presence of macrolide resistance genes (ermB, mefA, mel) was detected by PCR. RESULTS: A total of 52.8% of 140 S. pneumoniae isolates were macrolide-resistant: MLSB (89.2%) and M (10.8%). The MLSB phenotypes were genotypically confirmed by ermB gene presence. 62% had decreased susceptibility to penicillin. The serotypes were: 14, 1, 23F, and 19A. Serotype coverage by PCV7, PCV10 and PCV13 was 44.2%, 73.6%, and 75.6% respectively. CONCLUSION: 50% of S. pneumoniae isolates were macrolide resistant. The MLSB phenotype encoded by the ermB gene was the most frequent. Serotype coverage seems inadequate.
