[Evaluation of rapid genotype assay for the identification of gram-positive cocci from blood cultures and detection of mecA and van genes]. / Kan Kültürlerinde Üreyen Gram-Pozitif Koklarin Tanimlanmasi ve mecA ve van Genlerinin Saptanmasinda Hizli Genotip Testinin Degerlendirilmesi.

Rapid and accurate identification of bacterial pathogens grown in blood cultures of patients with sepsis is crucial for prompt initiation of appropriate therapy in order to decrease related morbidity and mortality rates. Although current automated blood culture systems led to a significant improvement in bacterial detection time, more rapid identification systems are still needed to optimise the establishment of treatment. Novel genotype technology which is developed for the rapid diagnosis of sepsis, is a molecular genetic assay based on DNA multiplex amplification with biotinylated primers followed by hybridization to membrane bound probes. The aim of this study was to evaluate the performance of "Genotype® BC gram-positive” test for the identification of gram-positive cocci grown in blood cultures and rapid detection of mecA and van genes. This test uses DNA.STRIP® technology which includes a panel of probes for identification of 17 gram-positive bacterial species and is able to determinate the methicillin and vancomycin resistance mediating genes (mecA and vanA, vanB, vanC1, vanC2/C3) simultaneously, in a single test run. A total of 55 positive blood cultures from BACTECTM Plus/F (Becton Dickinson, USA) aerobic and pediatric blood culture vials were included in the study. The isolates which exhibit gram-positive coccus morphology by Gram staining were identified by Genotype ® BC gram-positive test (Hain Life Science, Germany). All of the samples were also identified with the use of Phoenix PMIC/ID Panel (Becton Dickinson, USA) and antibiotic susceptibilities were determined. Of the 55 blood culture isolates, 17 were identified as Staphylococcus epidermidis [all were methicillin-resistant (MR)], 9 were S.aureus (one was MR), 18 were S.hominis (10 were MR), 4 were E.faecalis, 3 were E. faecium (one was vanconycin-resistant), 2 were S.saprophyticus (one was MR), 1 was S.warneri and 1 was S.haemolyticus, by Phoenix automated system. Genotype® BC gram-positive test results revealed consistency with Phoenix system regarding bacterial identification in 46 (83.6%) of the samples. The two bacteria identified as S.saprophyticus by the Phoenix system could not be identified by the Genotype® BC test since this species were not included in the identification panel of the system, however, mecA gene were detected in these two samples by Genotype® BC test. Genotype® BC test detected mecA gene in five samples which were not detected as methicillin resistant by the Phoenix system. Besides polymicrobial growth was determined in five samples by Genotype ® BC test, but not by the automated system. One E.faecium isolate with vanA gene was correctly identified by Genotype® BC test. In conclusion, Genotype® BC gram-positive test is a fast and reliable test for the identification of the most important gram-positive pathogens and mecA and van genes directly from positive blood culture bottles. This test was also found superior than the automated Phoenix system regarding the detection of polymicrobial growth. These data indicated that, routine use of DNA strip technology-based assay would be useful for clinical diagnosis in patients with sepsis.

[Comparison of microscopy and EIA in the diagnosis of Giardia intestinalis in stool specimens.]. / Giardiasisin tanisinda Enzym Immun Assay (EIA) ve direkt inceleme yöntemlerinin karsilastirilmasi

In this study; we compared the direct microscopic method and EIA test in the investigation of the stools of patients with gastrointestinal symptoms who presented at clinics. A total of 188 stool specimens collected from clinics were investigated by direct microscopy using native-Lugol preparations. Giardia cysts and/or trophozoites were observed in 141 specimens. There were no Giardia cysts and/or trophozoites or any other intestinal parasites detected in the other 47 stool specimens. The RIDASCREENR EIA kit procedure was applied in all specimens. Out of 141 specimens positive with direct microscopy, 136 specimens were positive with the EIA test and 5 specimens, negative. Parasites were not found in 47 stool specimens with direct microscopy. Of these, 38 specimens were negative with the EIA test and 9 specimens, positive. When the patient and control groups were compared, a significant difference was observed between the two methods (p < 0.05). The sensitivity and specificity of the EIA method that was used to determine the antigenic properties of G. intestinalis in stools were 96.4% and 80.8%, respectively.