COMPARISON OF 16S rRNA-PCR-RFLP, LipL32-PCR AND OmpL1-PCR METHODS IN THE DIAGNOSIS OF LEPTOSPIROSIS.

Leptospirosis is still one of the most important health problems in developing countries located in humid tropical and subtropical regions. Human infections are generally caused by exposure to water, soil or food contaminated with the urine of infected wild and domestic animals such as rodents and dogs. The clinical course of leptospirosis is variable and may be difficult to distinguish from many other infectious diseases. The dark-field microscopy (DFM), serology and nucleic acid amplification techniques are used to diagnose leptospirosis, however, a distinctive standard reference method is still lacking. Therefore, in this study, we aimed to determine the presence of Leptospira spp., to differentiate the pathogenic L. interrogans and the non-pathogenic L. biflexa, and also to determine the sensitivity and specificity values of molecular methods as an alternative to conventional ones. A total of 133 serum samples, from 47 humans and 86 cattle were evaluated by two conventional tests: the Microagglutination Test (MAT) and the DFM, as well as three molecular methods, the 16S rRNA-PCR followed by Restriction Fragment Lenght Polymorphism (RFLP) of the amplification products 16S rRNA-PCR-RFLP, LipL32-PCR and OmpL1-PCR. In this study, for L. interrogans, the specificity and sensitivity rates of the 16S rRNA-PCR and the LipL32-PCR were considered similar (100% versus 98.25% and 100% versus 98.68%, respectively). The OmpL1-PCR was able to classify L. interrogans into two intergroups, but this PCR was less sensitive (87.01%) than the other two PCR methods. The 16S rRNA-PCR-RFLP could detect L. biflexa DNA, but LipL32-PCR and OmpL1-PCR could not. The 16S rRNA-PCR-RFLP provided an early and accurate diagnosis and was able to distinguish pathogenic and non-pathogenic Leptospira species, hence it may be used as an alternative method to the conventional gold standard techniques for the rapid disgnosis of leptospirosis.

Molecular epidemiology and antibiotic susceptibility pattern of Acinetobacter baumannii isolated from children in a Turkish university hospital.

The aim of the present study is to investigate the types of healthcare-associated infections (HC-AIs) caused by Acinetobacter baumannii and the related antibiotic susceptibility patterns as well as the genotypic characteristics of the Acinetobacter baumannii isolates from our center. Sixty-nine Acinetobacter baumannii isolates originating from various samples collected from 69 pediatric patients during their hospital stays were included in the study. The types of healthcare-associated infections caused by these isolates were evaluated, and the antibiotic susceptibility pattern and the genotypic characteristics of the isolates were determined using the pulsed-field gel electrophoresis (PFGE) method. Fifty of the 69 children were observed to have HC-AIs, and 19 children had Acinetobacter baumannii colonization. Healthcare-associated pneumonia (58%) was the most common type of these infections. The rate of carbapenem resistance was found as 91.3%, while tigecycline resistance was found as 18.84%. No colistin resistance was observed in any of the isolates. A total of 10 groups, comprising eight major and two minor groups, were determined using the pulsed-field gel electrophoresis method. Acinetobacter baumannii isolates are the leading cause of healthcare-associated infections, and they show high rates of multidrug antibiotic resistance. Molecular epidemiological evaluation using PFGE plays an important role in preventing healthcare-associated infections.

Pseudomonas aeruginosa infections due to electronic faucets in a neonatal intensive care unit.

AIM: To evaluate the role of electronic faucets in a newborn intensive care unit during a Pseudomonas aeruginosa outbreak. METHODS: After three patients had P. aeruginosa bacteremia, environmental cultures including those from patient rooms, incubator, ventilators, total parenteral nutrition solutions, disinfection solutions, electronic and hand-operated faucet filters/water samples after removing filters and staff hands were taken. RESULTS: Only filters of electronic faucets and water samples after removing filters and one liquid hand soap showed P. aeruginosa (3-7 × 106 cfu/mL). We have removed the electronic faucets and new elbow-operated faucets were installed. Pulsed-field gel electrophoresis analysis of outbreak-blood culture isolates from two patients and isolates from electronic water faucets/one liquid hand soap indicated the presence of 90.7% genetically related subtype, probably from the same clone. Water cultures from new faucets were all clean after installation and after 7 months. CONCLUSION: We suggest that electronic faucets may be considered a potential risk for P. aeruginosa in hospitals, especially in high-risk units.