Identification of medically important Candida species by polymerase chain reaction-restriction fragment length polymorphism analysis of the rDNA ITS1 and ITS2 regions.

AIM: We aimed to identify the distribution of species in candidal strains isolated from clinical samples and restriction fragment length polymorphism (RFLP) method based on Msp I and Bln I restrictive enzyme cuts of polymerase chain reaction (PCR) products after the amplification of ITS1 and ITS2 regions of rDNA genotypically. MATERIALS AND METHODS: One hundred and fifty candidal strains isolated from various clinical samples were studies/ included. Phenotypic species assessment was performed using automated VITEK-2 system and kit used with the biochemical tests. Common genomic region amplification peculiar to candidal strains was carried out using ITS1 and ITS2 primer pairs. After the amplification, PCR products were cut with Msp I and Bln I restriction enzymes for species identification. RESULTS: The majority of Candida isolates were isolated from urine (78.6%) while other isolates were composed of strains isolated from swab, wound, blood and other samples by 11.3%, 3.3%, 2% and 4.7%, respectively. The result of RFLP analysis carried out with Msp I and Bln I restriction enzymes showed that candidal strains were Candida albicans by 45.3%, Candida glabrata by 19.3%, Candida tropicalis by 14.6%, Candida parapsilosis by 5.3%, Candida krusei by 5.3%, Candida lusitaniae by 0.6% and other candidal strains by 9.3%. CONCLUSION: When the ability to identify Candida to species level of phenotypic and PCR-RFLP methods was assessed, a great difference was found between these two methods. It may be argued that Msp I and Bln I restriction enzyme fragments can be used in the identification of medically important Candida species. Further studies are needed to develop this kind of restriction profile to be used in the identification of candidal strains.

Virulence Factors in Staphylococci Isolated From Nasal Cavities of Footballers.

AIM: This study aimed to investigate the rate of Panton-Valentine Leukocidin producing Staphylococcus aureus and methicillin (mecA) and slime (icaA/icaD) genes in staphylococcal strains isolated from nasal cavities of footballers. MATERIALS AND METHODS: Nasal swab samples were taken from each footballers and a healthy control group for the isolation of staphylococcal strains. The polymerase chain reaction technique was used to determine Panton-Valentine Leukocidin, mecA and icaA/icaD genes in staphylococcal isolates. RESULTS: Among 91 S. aureus strains, the presence of mecA gene was detected as 9.9%. This ratio was 17.9% (27 of 151) among the coagulase-negative staphylococci. A significant difference was found between coagulase-negative staphylococci and S. aureus isolates regarding the presence of mecA gene (P < 0.001). As for the genes of the slime, icaA/icaD genes were detected in 198 of 242 (81.8%) strains. The occurrence of slime genes was 91.2% and 89.4% among the S. aureus coagulase and negative staphylococci, respectively (P > 0.05). There was a statistically significant difference between the frequency of the mecA and slime genes when compared with the healthy control group and the football players (P < 0.01). Of 91 isolates, 22 were found to be methicillin resistant by the oxacillin disc diffusion method, whereas the remaining (220) were methicillin susceptible. Methicillin resistance was detected as 14.9% by the polymerase chain reaction method, whereas it was found as 9.1% by phenotypic methods. CONCLUSIONS: Early and accurate diagnosis of virulent staphylococcal strains is crucial because the virulent coagulase-negative and coagulase-positive staphylococcal strains in the nasal floras of footballers may be major potential sources of superficial and deep tissue infections.

Relationship between the resistance genes to quaternary ammonium compounds and antibiotic resistance in staphylococci isolated from surgical site infections.

BACKGROUND: We aimed to investigate the prevalence of disinfectant resistance genes (qacA/qacB,qacC) and the aminoglycosides resistance genes [(aac(6')aph(2''),aph(3')-IIIa,ant(4')-Ia)] in both S. aureus and coagulase-negative staphylococcal strains (CoNS) isolated from surgical site infections. MATERIAL AND METHODS: Totally, 130 staphylococcal strains isolated from surgical site infections between January 2012 and February 2013 were included in the study. The PCR technique was employed to verify any presence of methicillin resistance gene (mecA), aminoglycoside resistance genes [(aac(6')/aph (2''), aph(3)-III a ant (4')-1a)], and disinfectant resistance genes (qacA/qacB,qacC) in staphylococci. RESULTS: MecA gene was determined in 58 (44.6%) of 130 staphylococcal isolates. A total of 28 (73.7%) of 38 S. aureus isolates were found to be positive for the mecA gene, and 4 (12.9%) of 31 isolates sensitive to amikacin were sensitive to methicillin. Eighteen (47.4%) of 38 amikacin-resistant S. aureus isolates were found to be positive for qacA/qacB genes and 11 (8.9%) of them were positive for qacC gene. Both mecA and qacA/qacB genes were found to be positive at the same time in 19 amikacin-resistant S. aureus strains. Seven (18.4%) S. aureus isolates were determined to be positive for qacA/qacB and qacC genes. Frequency of qacA/B genes was found to be 47.4% among amikacin-resistant S. aureus strains, while qacC gene was found to be 28.9% (p<0.05). The ratio of qacA/B and qacC genes in CoNS was found to be 37.9% and 20.7%, respectively (p<0.05). CONCLUSIONS: Quaternary ammonium resistance genes were found to be positive at a remarkable ratio in the staphylococcal isolates from surgical wounds. Especially, the high rates of aminoglycosides and methicillin-resistance gene was remarkable in S. aureus isolates. Quaternary ammonium resistance genes were found to be positive.