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. © 2016, Instituto de Medicina Tropical de Sao Paulo. All rights reserved

Molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae at a Turkish centre: Is the increase of resistance a threat for Europe?

PubMedID: 28743652Objectives In recent years, carbapenem-resistant Klebsiella pneumoniae (CRKP) have become an important threat to hospitalised patients. This study aimed to identify the genetic mechanisms of carbapenem resistance in CRKP isolated from patients in a Turkish centre. Methods During 2013–2014, a total of 98 K. pneumoniae isolated from patients at Çukurova University Balcalı Hospital (Adana, Turkey) determined phenotypically as resistant to carbapenems were screened genotypically for the presence of carbapenemase enzymes by multiplex PCR. Results Of the 98 patients for whom genetic investigation was made, 93 (94.9%) were adults, 56 (57.1%) were male and 81 (82.7%) were diagnosed as infected. The mean and median age were 51.8 ± 20.5 years and 55 years (range 1–89 years), respectively. The nosocomial infection rate was 87.8% (86/98). The mortality rate was 41.8% (41/98). Fifty-eight patients (59.2%) were admitted to intensive care units. Of the 12 non-nosocomial infections, 5 (41.7%) originated from the inpatient clinic of the urology department. The mean and median hospital length of stay (LOS) were 20.7 ± 20.8 days and 17 days (range 0–90 days), respectively. The most common carbapenemase gene detected was blaOXA-48 (74.5%), followed by blaVIM (45.9%) and blaSME (37.8%). The blaNDM gene was detected in 20 isolates (20.4%). The most effective antibiotics were tigecycline and colistin, with susceptibility rates of 87.5% and 74.3%, respectively. Conclusions Multiple resistance mechanisms were present in CRKP isolates in Turkey. Most of the isolates harboured blaOXA-48, blaVIM and blaSME genes; meanwhile, the rate of 20.4% for blaNDM is alarming. © 2017 International Society for Chemotherapy of Infection and Cance