Molecular Epidemiological and Antibiotic Susceptibility Characterization of Brucella Isolates from Humans in Sicily, Italy

ABSTRACT Brucellosis is a serious problem in Sicily. Brucella melitensis was identified as the species most frequently isolated in humans in Italy. No data, however, are available about the molecular epidemiological characterization of Brucella isolates from humans. We have conducted this study to molecularly characterize clinical isolates of Brucella spp. and to evaluate their antimicrobial susceptibilities. Twenty Brucella isolates were studied. Differential growth characteristics and DNA polymorphisms such as the restriction patterns of the PCR-amplified omp2a and omp2b genes, rpoB nucleotide sequencing, and multiple-locus variable-number tandem repeat analysis of 16 loci (MLVA-16) were used to characterize the strains. In vitro antibiotic susceptibility was determined by the E-test method on two different agar media, and the results were compared. All isolates were identified as B. melitensis biovar 3. rpoB nucleotide sequence analysis allowed the identification of two different genotypes of B. melitensis biovar 3. On the other hand, the MLVA-16 typing assay recognized 17 distinct genotypes. All isolates were sensitive to all tested antibiotics (rifampin, doxycycline, ciprofloxacin, ceftriaxone, and trimethoprim-sulfamethoxazole), and the Mueller-Hinton agar plate is recommended for antibiotic susceptibility testing by the E-test method. Our findings identify B. melitensis biovar 3 as the etiological agent isolated in Sicily and encourage the use of both molecular methods, and in particular of the MLVA-16 assay, in epidemiological trace-back analysis. This study represents the first epidemiological data from molecular typing of Brucella strains circulating in Italy and, in particular, in eastern Sicily.

[1]  G. Vergnaud,et al.  Evaluation of Brucella MLVA typing for human brucellosis. , 2007, Journal of microbiological methods.

[2]  A. Cascio,et al.  Live Nativity and Brucellosis, Sicily , 2006, Emerging infectious diseases.

[3]  Y. Tselentis,et al.  In vitro susceptibilities of Brucella melitensis isolates to eleven antibiotics , 2006, Annals of Clinical Microbiology and Antimicrobials.

[4]  G. Escobar,et al.  A new variant of Brucella melitensis. , 2006, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[5]  P. Pasquali,et al.  Molecular characterization of the rpoB gene in Brucella species: new potential molecular markers for genotyping. , 2006, Microbes and infection.

[6]  H. Aggad,et al.  Prevalence of bovine and human brucellosis in western Algeria: comparison of screening tests. , 2006, Eastern Mediterranean health journal = La revue de sante de la Mediterranee orientale = al-Majallah al-sihhiyah li-sharq al-mutawassit.

[7]  F. Denoeud,et al.  Evaluation and selection of tandem repeat loci for a Brucella MLVA typing assay , 2006, BMC Microbiology.

[8]  A. Giovannini,et al.  Correlation between animal and human brucellosis in Italy during the period 1997-2002. , 2005, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[9]  Y. Zer,et al.  Synergy Tests by E Test and Checkerboard Methods of Antimicrobial Combinations against Brucella melitensis , 2005, Journal of Clinical Microbiology.

[10]  S. Kılıç,et al.  Characteristics of B. melitensis versus B. abortus bacteraemias. , 2005, The Journal of infection.

[11]  P. Pasquali,et al.  Genetic Bases of the Rifampin Resistance Phenotype in Brucella spp , 2004, Journal of Clinical Microbiology.

[12]  B. Dokuzoğuz,et al.  In vitro antimicrobial susceptibility of Brucella species. , 2004, International journal of antimicrobial agents.

[13]  R. M. Edelsten Techniques for the brucellosis laboratory , 1989, Veterinary Research Communications.

[14]  A. Erbay,et al.  Biotypes and Antimicrobial Susceptibilities of Brucella Isolates , 2003, Scandinavian journal of infectious diseases.

[15]  J. McDermott,et al.  Brucellosis in sub-Saharan Africa: epidemiology, control and impact. , 2002, Veterinary microbiology.

[16]  M. Refai Incidence and control of brucellosis in the Near East region. , 2002, Veterinary microbiology.

[17]  M. Ferraro Performance standards for antimicrobial susceptibility testing , 2001 .

[18]  M. Akova,et al.  Comparison of E Test to Microdilution for Determining In Vitro Activities of Antibiotics against Brucella melitensis , 1999, Antimicrobial Agents and Chemotherapy.

[19]  S. Caracappa Livestock production and animal health in Sicily, Italy. , 1999, Parassitologia.

[20]  A. Cloeckaert,et al.  Restriction site polymorphism of the genes encoding the major 25 kDa and 36 kDa outer-membrane proteins of Brucella. , 1995, Microbiology.

[21]  V. Pink Professional conduct: gift rapped. , 1994, European Quality Assurance Network newsletter.

[22]  F. Goldbaum,et al.  Urban outbreak of a Brucella melitensis infection in an Argentine family: clinical and diagnostic aspects. , 1994, FEMS immunology and medical microbiology.

[23]  G. Hatfull,et al.  Mycobacterium smegmatis RNA polymerase: DNA supercoiling, action of rifampicin and mechanism of rifampicin resistance , 1993, Molecular microbiology.

[24]  M. Corbel Identification of dye-sensitive strains of Brucella melitensis , 1991, Journal of clinical microbiology.

[25]  M. Banai,et al.  Isolation, identification, and characterization in Israel of Brucella melitensis biovar 1 atypical strains susceptible to dyes and penicillin, indicating the evolution of a new variant , 1990, Journal of clinical microbiology.

[26]  C. Gross,et al.  Characterization of the pleiotropic phenotypes of rifampin-resistant rpoB mutants of Escherichia coli , 1989, Journal of bacteriology.

[27]  C. Gross,et al.  Mapping and sequencing of mutations in the Escherichia coli rpoB gene that lead to rifampicin resistance. , 1988, Journal of molecular biology.

[28]  Joint Fao,et al.  Joint FAO/WHO Expert Committee on Brucellosis : sixth report , 1986 .

[29]  E. Bruck,et al.  National Committee for Clinical Laboratory Standards. , 1980, Pediatrics.

[30]  C. Dolea,et al.  World Health Organization , 1949, International Organization.