Betil Özhak Baysan

The role of Bifidobacterium lactis B94 plus inulin in the treatment of acute infectious diarrhea in children

BACKGROUND/AIMS In contrast to many other studies of probiotic species, the number of publications evaluating Bifidobacterium lactis and its combinations with prebiotics as treatments for acute infectious diarrhea is limited. We investigated the synbiotic effects of B. lactis B94 plus inulin on acute infectious diarrhea. MATERIALS AND METHODS The study was conducted on children with acute diarrhea between the ages of 2 and 60 months. The patients were administered 5×1010 colony-forming units (CFU) of B. lactis B94 plus 900 mg inulin or placebo, once a day for five days. Stools were examined for Rotavirus, Adenovirus, Entamoeba histolytica, Salmonella, Shigella, Campylobacter, Clostridium difficile, Cryptosporidium, and parasites. RESULTS We examined 79 patients in the synbiotic group and 77 patients in the placebo group. The duration of diarrhea was significantly reduced in the synbiotic group in comparison with the placebo group (3.9±1.2 days vs. 5.2±1.3 days, respectively; p<0.001). Moreover, the number of diarrheal stools on the third day was significantly lower in the synbiotic group than in the placebo group (5.5±2.9 vs. 8.3±3.01, respectively; p<0.001). Diarrhea in the synbiotic-group patients with rotavirus infection was of a significantly shorter duration (3.2±1.3 days vs. 5.2±1.3 days, respectively; p=0.001). Duration of diarrhea in patients who started the synbiotic treatment within the first 24 h was shorter than that in the patients who started the treatment later (3.9±1.1 days vs. 4.8±1.8 days, respectively; p=0.002). CONCLUSION Treatment with 5 × 1010 CFU of B. lactis B94 plus 900 mg inulin shortened the duration of acute watery diarrhea by an average of 31 h. This decrease was most pronounced in cases of Rotavirus diarrhea.

Evaluation of Brilliance VRE agar for the detection of vancomycin-resistant enterococci in rectal swab specimens.

Vancomycin-resistant enterococci (VRE) infections in hospitalized patients cause significant morbidity and mortality, and current recommendations for hospital infection control include VRE faecal surveillance cultures (Stamper et al., 2007). However, the optimal methods for these cultures have not been defined (Delmas et al., 2007). This study compared the performance of novel chromogenic medium Brilliance VRE agar (Oxoid; Thermo Fisher Scientific) with that of traditional culture to screen rectal swab specimens for VRE. Brilliance VRE agar is a selective and differential chromogenic agar for the detection of vancomycinresistant Enterococcus faecium and vancomycin-resistant Enterococcus faecalis. Brilliance VRE agar contains two chromogens that are targeted by specific enzymes: phosphatase and a-galactosidase. The presence of phosphatase enzymes in both E. faecium and E. faecalis results in light blue colonies. However, E. faecium also produces a-galactosidase, resulting in a mix of blue and pink chromophores within the bacterium, producing indigo to purple colonies.

Comparison of four methods for rapid identification of Staphylococcus aureus directly from BACTEC 9240 blood culture system

PURPOSE Differentiation of Staphylococcus aureus (S. aureus) from coagulase-negative staphylococci is very important in blood stream infections. Identification of S. aureus and coagulase-negative staphylococci (CoNS) from blood cultures takes generally 18-24 h after positive signaling on continuously monitored automated blood culture system. In this study, we evaluated the performance of tube coagulase test (TCT), slide agglutination test (Dry Spot Staphytect Plus), conventional polymerase chain reaction (PCR) and LightCycler Staphylococcus MGrade kit directly from blood culture bottles to achieve rapid identification of S. aureus by using the BACTEC 9240 blood culture system. MATERIALS AND METHODS A total of 129 BACTEC 9240 bottles growing gram-positive cocci suggesting Staphylococci were tested directly from blood culture broths (BCBs) with TCT, Dry Spot Staphytect Plus, conventional PCR and LightCycler Staphylococcus MGrade kit for rapid identification of S. aureus. RESULTS The sensitivities of the tests were 99, 68, 99 and 100%, respectively. CONCLUSION Our results suggested that 2 h TCT was found to be simple and inexpensive method for the rapid identification of S. aureus directly from positive blood cultures.

Evaluation of Vancomycin Resistance 3 Multiplexed PCR Assay for Detection of Vancomycin-Resistant Enterococci from Rectal Swabs

Background Active screening for vancomycin-resistant enterococci (VRE) using rectal specimens is recommended to limit the spread of antimicrobial resistance within certain high-risk populations. We evaluated the diagnostic performance of Vancomycin Resistance 3 Multiplexed Tandem PCR assay (AusDiagnostics, Australia), a rapid multiplex real-time PCR assay that detects vanA and/or vanB. Methods Two-hundred-and-eleven rectal swabs from Hematology and Oncology unit were submitted for VRE surveillance via direct detection of vanA and/or vanB by culture and by using Vancomycin Resistance 3 Multiplexed Tandem PCR assay. Enterococci were identified to the species level by using standard biochemical tests and BD Phoenix Automated Microbiology System (BD Diagnostic Systems, USA). Vancomycin susceptibility of enterococci was determined using Etest (BioMerieux, France). Results Compared to the culture method, Vancomycin Resistance 3 Multiplexed Tandem PCR assay had a sensitivity of 84.0%, specificity of 98.8%, positive predictive value (PPV) of 91.3%, and negative predictive value (NPV) of 97.6%. The assay failed to detect 18 (8.5%) specimens because of the presence of PCR inhibitors; of the remaining 193 specimens, 25 (12.9%) were positive, 23 for vanA, and 2 for vanB. Although both sensitivity and specificity for vanA VRE was 100% compared to the culture method, all vanB-positive specimens tested negative by VRE culture. Conclusions Vancomycin Resistance 3 Multiplexed Tandem PCR assay is a rapid and laborsaving option for VRE surveillance for direct use on rectal swabs. However, the high rate of PCR failure owing to the inhibitors in the specimens and the low specificity for vanB should be considered when interpreting the results.

Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry (MALDI- TOF MS) for Early Identification of Septic Patients

BACKGROUND Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a powerful technique for the rapid identification of bacteria from growing colonies in routine cultures. In this study, we evaluated the feasibility of a 5-hour incubation on solid medium after sub-cultivation of positive blood culture broth without any preparation steps in order to speed up the identification of bacteria. METHODS In addition to standard laboratory protocols, a Columbia agar plate with 5% sheep blood was inoculated with 1 drop from the blood culture broth. After a 5-hour incubation period, a colony from the culture plate was submitted to MALDI-TOF MS. RESULTS A total of 1351 positive blood cultures (1299 monomicrobial and 51 polymicrobial) were analyzed. When compared to routine identification procedure results for positive blood cultures, 79.3% of isolates were correctly identified to the species level. When manufacturer-recommended score values were taken into account, MALDITOF MS correctly identified 98.4% of the isolates to the species level with a score of > 2.0, 89.1% with a score between 1.7 and 2.0, and 75.4% with a score of < 1.7. CONCLUSIONS ln our evaluation, a large majority of the S. aureus (91.5%) and Enterobacteriaceae (87.6%) were correctly identified at the species level. A 5-hour incubation period was found to be associated with moderate identification results for CoNS, Enterococcus spp., and nonfermentative gram negative bacilli, with failure being mostly observed with Streptococcus spp., Candida spp., and other gram positive bacteria. We believe that the performance of MALDI-TOF MS identification after short-term culture is directly related to the sufficient growth of microorganisms at 5 hours.

Evaluation of a CHROMagar Salmonella Medium for the Isolation of Salmonella Species

1 Yeşim Çekin1, Özlem Koyuncu Özyurt2, Duygu Dağlar3, Hafize Kılınçkaya Doğan2, Betil Özhak Baysan2 Aylin Erman Daloğlu2, Gözde Öngüt2, Dilara Öğünç2, Dilek Çolak2, Belkıs Levent4 1Antalya Eğitim ve Araştırma Hastanesi, Tıbbi Mikrobiyoloji, Antalya, 2Akdeniz Üniversitesi Tıp Fakültesi, Tıbbi Mikrobiyoloji A.D., Antalya 3Serik Devlet Hastanesi, Antalya, 4Türkiye Halk Sağlığı Kurumu, Ankara, Türkiye CHROMagar Salmonella Besiyerinin Değerlendirilmesi / Evaluation of a CHROMagar Salmonella Medium Evaluation of a CHROMagar Salmonella Medium for the Isolation of Salmonella Species

Comparison of selective and enrichment media for isolation of vancomycin-resistant enterococci from rectal swab specimens.

colonies formed on Enterococcosel agar were subcultured to blood-agar plates containing 5% sheep’s blood and incubated at 35°C for 24 h. All isolates were identified by colony morphology, Gram stain and biochemical tests. Species identification and antimicrobial susceptibility testing was performed using BD Phoenix System (BD Diagnostic Systems, USA). The minimal inhibitory concentrations (MICs) of vancomycin and teicoplanin were also determined by Etest method (BioMérieux, France). Carriage of vanA or vanB gene was confirmed using BD GeneOhm VanR assay (BD Diagnostic Systems, USA), a rapid real-time polymerase chain reaction (PCR) test, according to the manufacturer’s instructions.