Yazar "Balikci A." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Yayın
    A frequently overlooked bacteria in clinical microbiology laboratories: Arcanobacterium haemolyticum [Klinik mikrobiyoloji laboratuvarinda siklikla atlanan bir etken: Arcanobacterium haemolyticum]
    (2011) Balikci A.; Topkaya A.E.; Belaş Z.
    Arcanobacterium haemolyticum, previously known as Corynebacterium haemolyticum, is a facultative anaerobic, gram-positive bacillus with negative catalase and positive CAMP inhibition test results. It may be the causative agent of about 0.5-3% of acute bacterial pharyngitis especially in children and young adults. Since growth of A.haemolyticum is usually inhibited by flora members and since it slowly develops hemolysis in sheep blood agar and its colony morphology resembles beta-he-molytic streptococci, it is frequently overlooked in the evaluation of throat cultures. The aims of this study were to investigate the isolation frequency of A.haemolyticum from the throat cultures of pediatric patients by using both sheep and human blood agar media, and to evaluate the performances of those media for the identification of A.haemolyticum. A total of 355 patients (median age: 7 years) who were admitted to pediatric outpatient clinics with the symptoms of tonsillopharyngitis between March-July 2010 period, were included in the study. Swab samples obtained from tonsils and posterior oropharynx were inoculated into a divided plate which contained 5% sheep blood agar in one half and 5% human blood agar in the other half. After incubation in 5% CO 2 at 37°C, the beta-hemolytic colonies with a microscopic morphology of gram-positive bacilli were further evaluated on 24, 48 and 72 th hours. Identification of A.haemolyticum was based on negative catalase test, positive reverse CAMP test and biochemical characteristics obtained by API-Coryne (bioMérieux, France) identification system. In our study, beta-hemolytic colonies were detected in the throat cultures of 56 (16%) patients, of which 14% (49/355) were identified as beta-hemolytic streptococci (46 group A, 2 group G, 1 group C), and 2% (7/355) were identified as A.haemolyticum. All of the A.haemolyticum isolates were characterized by the production of beta-hemolysis in human blood agar at 24 hours, while the beta-hemolysis generation time in sheep blood agar was 48 hours for four isolates and 72 hours for three isolates. A.haemolyticum was identified in 2% of children with tonsillopharyngitis during the five months study period in spring/summer. All of the strains were isolated at human blood agar in 24 hours. Thus, in order to isolate A.haemolyticum in routine throat cultures, sheep blood agar plates together with human blood agar plates should be used in clinical microbiology laboratories.
  • Küçük Resim Yok
    Yayın
    Serotypes and antimicrobial susceptibilities of invasive group a streptococci identified in Eastern Black Sea Region of Turkey [Türkiye'nin dogu karadeniz bölgesinden tanimlanmiş invazif a grubu streptokoklarin serotipleri ve antimikrobiyal duyarliliklari]
    (2011) Bayramoglu C.; Topkaya A.E.; Balikci A.; Aydin F.
    Frequency of invasive group A streptococcus (GAS) infections is increasing worldwide in recent 20 years. Serotypes responsible for these clinical manifestations and their antibiotic susceptibilities should be known in order to establish preventive measures and initiate appropriate treatment. This study was aimed to determine the serotypes, antibiotic susceptibilities and inducible clindamycin resistance among invasive GAS isolated between 2006-2009 period. A total of 22 GAS strains isolated from clinical samples [sterile body fluids (peritoneal, pleural, pericardial, joint and cerebrospinal fluids), blood, tissue biopsy] of the patients (14 male, 8 female; age range: 3-82 years, median age: 59) who admitted to Karadeniz Technical University Faculty of Medicine, Farabi Hospital located in Trabzon province (Eastern Black Sea Region of Turkey), between March 2006 and March 2009 were included in the study. GAS serotypes were determined by the investigation of serum opacity factors (SOF), T proteins and M proteins. SOF production was investigated by microplate method using human serum and SOF types were determined by SOF-inhibition test using specific antisera. T protein types were detected by agglutination method using polyvalent anti-T sera, and M serotypes were detected by capillary precipitation method using M antisera. Antimicrobial susceptibility tests were performed by disk-diffusion method according to CLSI recommendations. SOF were positive in 9 (41%) samples. Use of T antiserum yielded T (n= 8) and U (n= 7) types and M antiserum M1 (n= 4) and M2 (n= 3) types. The overall antibiotic susceptibility rate of the isolates was 68% (15/22) and overall resistance rate was 32% (7/22). All of the GAS strains were found susceptible to benzylpenicillin, ceftriaxone, vancomycin, levofloxacine and linezolid, however 9 (41 %) were intermediate susceptible to tetracycline and 1 (4.5%) was intermediate susceptible to erythromycin. Four (18%) strains were found resistant to tetracycline, while three strains (13.5%) were found resistant to chloramphenicol. Inducible clindamycin resistance was found positive only in one strain. The serotypes determined in this study indicated that 33% of our invasive serotypes were covered by the hexavalent vaccine and 62% by the 26-valent vaccine. Multi-center surveillance studies are required to determine the serotype distribution of invasive GAS in Turkey and to provide valuable information for the development of appropriate vaccines in our country.