Diagnostic Role of Opsonic Activity in Acinetobacter baumannii Ventilator-Associated Pneumonia.

In this study, we investigated the diagnostic value of opsonic activity against Acinetobacter baumannii in Ventilator-Associated Pneumonia (VAP) among 50 patients, compared to 102 negative and positive controls. Out of the 50 patients, only 33 (66 %) were diagnosed with VAP using the Clinical Pulmonary Infection Score (CPIS). The opsonic activity assay demonstrated three key findings: (i) 95 % sensitivity and 91.7 % specificity, with a Receiver Operating Characteristic (ROC) area of 0.976 for distinguishing A. baumannii culture positives from negatives; (ii) 95 % sensitivity and 78.7 % specificity, with a 0.915 ROC area, in differentiating VAP/blood culture positive patients from colonized/negative groups; (iii) An ROC area of 0.553 for VAP and colonization, as identified by CPIS alone, indicating an indeterminate threshold. These results highlight that CPIS, microbiological, and clinical evaluations were not correlated, suggesting that opsonic activity against A. baumannii could be a potential VAP diagnostic tool, with the need for large-scale validations.

Serological Evidence of Tick-Borne Encephalitis and West Nile Virus Infections Among Children with Arthritis in Turkey.

Tick-borne encephalitis virus (TBEV) and West Nile virus (WNV) are mainly transmitted by arthropod vectors to vertebrate hosts including humans, resulting in fever and neurological signs. The aim of this study was to investigate the presence of antibodies to TBEV and WNV, and TBEV-RNA and WNV-RNA in Turkish children with fever and/or arthritis. For this purpose, 110 sera and buffy-coat samples were collected; sera were analyzed by indirect enzyme-linked immunosorbent assay for the presence of IgM and IgG antibodies to TBEV and WNV, and buffy-coat-derived white blood cells were analyzed by quantitative real-time RT-PCR for TBEV-RNA and WNV-RNA. IgM antibodies to TBEV were detected in five children between the ages of 3 and 7 years; no IgG antibodies to TBEV were detected. IgG antibodies to WNV were detected in two children and IgM antibodies to WNV were detected in six children, between the ages of 3 and 7 years. One of the children had IgM antibodies to WNV and to TBEV. Children who had antibodies to TBEV and WNV had fever and/or arthritis but no obvious neurological signs. Molecular diagnostic approaches revealed that neither TBEV-RNA nor WNV-RNA was present in any of the buffy-coat samples, not even in children with IgM-specific antibodies. Our serological results indicate that children in Turkey are exposed to TBEV and WNV.

Genotypes of hepatitis a virus in Turkey: first report and clinical profile of children infected with sub-genotypes IA and IIIA.

BACKGROUND: Hepatitis A virus (HAV) is a food and water-borne virus causing clinical (mainly hepatitis) and subclinical disease in humans. It is important to characterize circulating strains of HAV in order to prevent HAV infections using efficacious vaccines. The aim of this study was the detection and characterization of the circulating strains of HAV in Turkey by performing serology, RT-PCR, sequencing and phylogenetic analysis. METHODS: In this study, 355 HAV suspected cases were analysed by ELISA for the presence of antibodies to HAV. RNA was extracted from 54 HAV IgM positive human sera. None of the suspect cases were vaccinated against HAV and they never received blood transfusions. Samples found positive by RT-PCR using primers targeting the VP1/VP2A junction and VP1/VP3 capsid region of HAV, were subjected to sequencing and phylogenetic analyses. RESULTS: IgM type antibodies to HAV were detected in 54 patients. Twenty one of them were students. The age of IgM positive cases was between 3 and 60 years. IgM positivity differed in age groups and was higher in the age group 3 to 10 years. Phylogenetic analysis showed that the majority of HAV strains detected in this study belong to the "HAV 1B" cluster. In addition, the HAV sub-genotypes IA (KT874461.1) and IIIA (KT222963.1) were found in 2 children. These sub-genotypes were not previously reported in Turkey. The child who carried sub-genotype IIIA travelled to Afghanistan and presented with abdominal pain, icterus and vomitus. He was positive for anti-HAV IgM and IgG but negative for hepatitis B and C. Liver enzymes like aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase and lactate dehydrogenase were severely elevated. Bilirubin levels were also increased. White blood cells, neutrophils and hemoglobin were decreased while lymphocytes and monocytes were increased. Similar clinical signs and laboratory findings were reported for the child infected with sub-genotype IA but aspartate aminotransferase and alanine aminotransferase were not severely elevated. CONCLUSIONS: The results indicate that molecular studies determining the HAV genotype variation in Turkey are timely and warranted. The majority of IgM positive cases in 3-10 year old patients indicate that childhood vaccination is important. Sub-genotype IB is the most prevalant genotype in Turkey. Surprisingly, sub-genotype IA and IIIA are also present in Turkey; future diagnostic efforts need to include diagnostic methods which can identify this emerging HAV genotypes. Our results also show that one important risk factor for contracting hepatitis A virus is international travel since genotype IIIA was detected in a child who had travelled to Afghanistan.

Evaluation of Adenovirus-36 (Ad-36) antibody seropositivity and adipokine levels in obese children.

Adenovirus 36 (Ad-36) has recently been suggested as a possible contributor to the current obesity epidemic. The aim of this study was to investigate the prevalence of Ad-36 antibodies in obese children, as well as investigate the role of serum leptin and lipid levels in Ad-36-obesity. Seventy-one obese children and 62 non-obese children were included as the patient group (PG), including the healthy control group (HCG), respectively. Simultaneously, Ad-36 antibodies and adipokine levels were assessed with serum neutralization assays (SNA) and ELISA. Ad-36 antibody was detected in 9 patients (12.7%) and 1 patient (1.6%) in both the PG and HCG, respectively, while a significant difference was detected between groups (p < 0.05). Although serum LDL, total cholesterol, triglycerides and leptin levels were detected significantly higher, adiponectin level was detected paradoxically lower in the PG. However, a significant difference was not detected for lipids and leptin levels; adiponectin levels were found to be significantly lower in Ad-36 antibody-positive PG (p < 0.05). In conclusion, we suggest there is an association between Ad-36 and obesity in children, including IL-6 levels increasing in obese children with Ad-36 seropositivity. Conversely, adiponectin levels in obese children with Ad-36 seropositivity were higher. As such, there is a need for studies to understand the mechanisms underlying this observation.

Determination of clinical significance of coagulase-negative staphylococci in blood cultures.

The aim of this study was to investigate the criteria used to distinguish coagulase-negative staphylococci (CoNS) bacteremia from contamination. We evaluated 162 adult patients with CoNS-positive blood cultures (BCs). Of the 162 patients, 35 (21.6%) had at least 2 positive BCs and 127 (78.4%) had a single positive BC. According to the Laboratory-Confirmed Bloodstream Infection (LCBI) criteria, 24 (14.8%) patients with the same species of CoNS had true bacteremia, and 138 (85.2%) patients had contaminants. Despite the detection of the same CoNS species, 9 of the 24 patients had different CoNS genotypes. Using clinical assessments, only 20 patients were diagnosed with true bacteremia, 8 of them had a single positive BC. We concluded that only using the LCBI criteria or clinical evaluations of a patient were not sufficient to distinguish CoNS bacteremia from contamination. Molecular identification should also be performed as a diagnostic laboratory parameter for CoNS bacteremia.

Investigation of carbapenem resistance and the first identification of Klebsiella pneumoniae carbapenemase (KPC) enzyme among Escherichia coli isolates in Turkey: A prospective study.

BACKGROUND: The aim of this study was to determine the presence of carbapenem resistance and carbapenemase production in Escherichia coli isolates from clinical samples in Turkey. METHODS: The prospective study included a total of 4.052 Escherichia coli isolates collected from patients admitted to a hospital from March 2011 to May 2012. We used ertapenem disc for screening carbapenemase production, and the confirmation was performed by using Etest. The resistance mechanisms and genetic relatedness of the carbapenem resistant strains were investigated by using PCR (polymerase chain reaction) and pulsed-field gel electrophoresis (PFGE), respectively. RESULTS: Among the 4.052 E. coli isolates, 24 (0.59%) were found to be carbapenem resistant. Of these, only 5 isolates were positive for OXA-48 and 2 isolates were positive for Klebsiella pneumoniae carbapenemase (KPC)-2. The KPC-2 producing E. coli strains (n = 2) were both isolated from the same patient. The blaKPC genes were confirmed using DNA sequence analysis. The genetic relationship between the 24 E. coli strains studied by PFGE revealed that the strains were genetically unrelated. CONCLUSIONS: This article confirms, to our knowledge for the first time, the detection of KPC-2-producing E. coli in Turkey, with OXA-48 being the most frequent carbapenemase in the study.

Travel-associated infections caused by unusual serogroups of Legionella pneumophila identified using Legionella BIOCHIP slides in Turkey and Iraq.

BACKGROUND: Although Legionella pneumophila serogroup 1 is the common disease causing serogroup, rare serogroups can also may cause legionellosis. A 54-year-old male patient (index case) reported that he had been on a religious trip (for visiting, tomb of Ali, which is important for Shias) to Iraq with a large group (50 shia pilgrims from Kars city of Turkey) two weeks prior to admission. Due to civil war, the hotel where the patient stayed in Iraq lacked proper hygiene. A large number of people in the travel group were experiencing the same symptoms. Other five cases were 2 males (ages; 50, 45) and 3 females including the wife of the index case (ages; 50, 28, 27). METHOD: The detection of L. pneumophila IgG and IgM was performed by anti-L. pneumophila Indirect Immunofluorescent IgM, IgG kit. Legionella 1 biochip/verification BIOCHIP slides were used for serogrouping in Euroimmun AG, Leubeck, Germany. RESULTS: In index case, L. pneumophila IgM was positive with a titer of 1/32 titer. IgG was negative with a 1/100 titer. Another case (28 year old female), had clinical symptoms identical to the index case. L. pneumophila IgM and IgG were positive with titers of 1/64 and 1/100, respectively. These two cases were diagnosed with Legionnaires' disease caused by L. pneumophila serogroup 12 (index case) and female (28-year-old) by serogroup 11. The other 4 cases were diagnosed with possible Pontiac fever caused by L. pneumophila serogroups 14 (wife of the index case), 4, and 6 whereas the serogroup of L. pneumophila detected in 27 years old female case could not be identified. CONCLUSION: A major limitation of this work is the absence of genotyping and the serogroup difference between index case and his wife who shared the same hotel. We suggest that this serogroup difference may be caused by (for men and women) sitting separately in Islamic rules. On the other hand, the movement of people in the context of mutual visits between countries or neighboring countries for tourism-related (i.e., for religious events or visits to holy sites) or immigration-related reasons, may cause some epidemic diseases. This study reemphasized that not only L. pneumophila serogroup 1, but other rare serogroups might cause also legionellosis which may increase in frequency and cause regional epidemics. We propose that increased financial resources for improving the hygiene conditions and performing routine legionella surveillance studies in touristic hotels would be useful measures for legionellosis prevention and control.

Patterns of EPIYA motifs among cagA-positive Helicobacter pylori strains: a case-control study in a Turkish population with Eurasian geographical features.

Geographical variation in the frequency of various gastroduodenal pathologies was shown to be related to the geographical diversity of H. pylori CagA Glu-Pro-Ile-Tyr-Ala (EPIYA) patterns. We examined the EPIYA patterns of H. pylori and the association of EPIYA patterns with gastric cancer (GC) for the first time, to the best of our knowledge, in Turkey. The patient group (PG) contained 60 patients [38 GC and 22 duodenal ulcer (DU) patients]. The control group (CG) was 110 individuals [94 gastritis patients and 16 persons with a normal gastrointestinal system (NGIS)]. Specific primers were used for the detection of cagA including empty-site-positive and EPIYA-A, -B, -C, -D PCR. Bands of EPIYA-A, -B, -C were confirmed by DNA sequencing. One hundred and forty-two (83.5 %) strains [60 in the PG (38 GC, 22 DU), 82 in the CG (72 gastritis, 10 NGIS)] were positive for the cagA gene. EPIYA-C with multiple repeats was detected in 34 (23.9 %) strains, and 22 (64.7 %) were from GC patients. EPIYA-C with one repeat was detected in 89 (62.7 %) strains, and 54 (60.7 %) were from gastritis patients. EPIYT was detected in 10 strains, and EPIYA-D was not detected. The number of EPIYA-C with multiple repeats was significantly higher for the PG than for the CG (P < 0.0001). In GC patients, the number of EPIYA-C with multiple repeats was significantly higher than one repeat (P < 0.0001). In conclusion, our study showed that multiple EPIYA-C repeats increases the GC risk by 30.6-fold and the DU risk by 8.9-fold versus the CG. This indicates that Western-type H. pylori strains in Turkey have similar EPIYA motifs to those of neighbouring countries and Western populations.

The role of adenovirus 36 as a risk factor in obesity: the first clinical study made in the fatty tissues of adults in Turkey.

Obesity which developes due to multifactorial reasons, was associated recently with human Adenovirus-36 (Ad-36). The aim of this study was to investigate the prevalence of Ad-36 antibodies in obese adults and also to investigate the DNA of Ad-36 in their adipose tissue. In this cross-sectional and case-control based study, 49 obese adults, with BMI ≥ 30 kg/m(2), and 49 non-obese adults, with BMI ≤ 25 kg/m(2), applied for esthetic purposes and were included in this study as patient and control groups, respectively. Adipose tissue samples, obtained by the lipoaspiration method, were studied by single-step PCR and nested-PCR methods. Simultaneously, the presence of Ad-36 antibodies and serum leptin and adiponectin levels were assessed by serum neutralization assay (SNA) and ELISA, respectively. Serum samples which didn't cause a cytopathic effect at ≥ 1:8 were accepted as positive. Ad-36 antibody was detected in 6 (12.2%) of 49 patients by SNA and was statistically significant (p < 0.05). Ad-36 DNA was not detected in any of the adipose tissue samples of the patient or control groups. Mean BMI and leptin levels were higher in the Ad-36-positive group, while adiponectin levels were found to be lower in the Ad-36-positive group. Although no statistically significant difference was found in cholesterol and triglyceride levels between the two groups (p > 0.05), lower mean serum cholesterol and triglyceride levels were found in the Ad-36-positive patients. In conclusion, we couldn't detect Ad-36 DNA in adipose tissue; however, we detected significantly higher Ad-36 antibody levels in the obese group compared to the non-obese group, according to the both univariant and multivariant analyses, suggesting that Ad-36 may play a role in obesity. There is a need for new and extended serial, particularly cohort and human-based, studies in order to have a clear understanding of the Ad-36-obesity relationship.

Microorganisms in respiratory tract of patients diagnosed with atypical pneumonia: results of a research based on the use of reverse transcription polymerase chain reaction (RT-PCR) DNA microarray method and enzyme-linked immunosorbent assay.

BACKGROUND: Numerous molecular-based tests were applied for the laboratory-based diagnosis of viruses. In this cross-sectional case control study, in addition to bacteria, we aimed to determine respiratory viruses using, for the first time in our country, the Reverse Transcription PCR DNA Microarray method, and we also aimed to evaluate its diagnostic performance. METHODS: Respiratory viruses were investigated from nasopharyngeal swabs of 76 patients diagnosed with atypical pneumonia and 64 healthy controls using the CLART Pneumovir (Genomica, Spain) kit and from 10 mL blood samples of the same subjects. M. pneumoniae IgM was detected by ELISA and L. pneumophila IgM and C. pneumoniae IgM by indirect immunofluorescence. Person's chi-square test was used for statistical analysis. RESULTS: Our results showed that the specificity (100%) and the positive predictive value (100%) of the CLART Pneumovir kit were high, but its sensitivity (53%), its negative predictive value (64%), and its kappa value (50%) were low. Parainfluenza Virus type 3 and M. pneumoniae were found alone or together as the most common microorganisms while no cases of human bocavirus, adenovirus, rhinovirus, or coronavirus were detected. CONCLUSIONS: Our results demonstrated that, during the study period, most of our patients had atypical pneumonia due to Parainfluenza Virus type 3 and M. pneumoniae co-infection.

The relationship between bifidobacteria and allergic asthma and/or allergic dermatitis: a prospective study of 0-3 years-old children in Turkey.

Bifidobacteria are beneficial bacteria for humans. These bacteria are particularly effective at protecting against infectious diseases and modulating the immune response. It was shown that in newborns, the fecal distribution of the colonizing Bifidobacterium species influences the prevalence of allergic diseases. This study aimed to compare the faecal Bifidobacterium species of allergic children to those of healthy children to detect species level differences in faecal distribution. Stool samples were obtained from 99 children between 0 and 3 years of age whose clinical symptoms and laboratory reports were compatible with atopic dermatitis and allergic asthma. Samples were also obtained from 102 healthy children who were similar to the case group with respect to age and sex. Bifidobacteria were isolated by culture and identified at the genus level by API 20 A. In addition, 7 unique species-specific primers were used for the molecular characterization of bifidobacteria. The McNemar test was used for statistical analyses, and p < 0.05 was accepted as significant. Bifidobacterium longum was detected in 11 (11.1%) of the allergic children and in 31 (30.3%) of the healthy children. Statistical analysis revealed a significant difference in the prevalence of B. longum between these two groups (X(2): 11.2, p < 0.001). However, no significant differences in the prevalence of other Bifidobacterium species were found between faecal samples from healthy and allergic children. (p > 0.05). The significant difference in the isolation of B. longum from our study groups suggests that this species favors the host by preventing the development of asthma and allergic dermatitis. Based on these results, we propose that the production of probiotics in accordance with country-specific Bifidobacterium species densities would improve public health. Thus, country-specific prospective case-control studies that collect broad data sets are needed.

The epidemiological and molecular characterization of vancomycin-resistant enterococci isolated from rectal swab samples of hospitalized patients in Turkey.

BACKGROUND: Vancomycin-resistant enterococci (VRE) are a serious problem all over the world. The present study was conducted to investigate antimicrobial resistance patterns, genotypes, clonal relationship, and virulence fac- tors of VRE species isolated from rectal swab samples of hospitalized patients, patient's relatives, and medical staff at Istanbul University Cerrahpasa Medical School hospital. METHODS: The VRE isolates were typed with an automated VITEK system and their antibiotic sensibilities were analysed by disc diffusion and Etest® method. The molecular characterization and clonal relationships were per- formed using a PCR method and virulence genes by sequence typing. RESULTS: A total of 100 (10.3%) of the 971 patients were colonized with VRE. None of the investigated 25 patient's relatives and 45 medical staff carried VRE. All VRE strains were identified as E. faecium. They were vanA genotype and originated from a single clone. VRE strains exhibited multi-drug resistance. High-level gentamicin-resistance was 93%. However, lower resistance rates were found for linezolid (40%) and quinopristin-dalfopristin (11%). The enterococcal surface protein gene esp was found positive in 87 of 100 isolates, and four strains were positive for the cylB (cytolysin) gene. CONCLUSIONS: The identification of VRE strains to the species level and detection of virulence genes will assist in infection control practices.