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Serkan Oncu

Publications and source records attributed to Serkan Oncu.

11 recordsLinked to original sources
PubMed2006

The effect of Blastocystis hominis on the growth status of children.

BACKGROUND: B. hominis is a protozoan parasite commonly found in the human gastrointestinal tract. The pathogenesis of B. hominis is still controversial, although it is one of the most common parasites found in stool samples. MATERIAL/METHODS: This study was conducted at the Adnan Menderes Medical Faculty between January 2002 and June 2003 to evaluate the relationship between B. hominis and growth status in children in Aydin, Turkey. Healthy children with positive stool samples for B. hominis but negative for other parasites were selected as the case group (n=89). Two controls matched to each case by age and gender were selected by random sampling of children with negative stool samples for any parasite (n=178). RESULTS: The anthropometric measurements and body mass index were significantly lower in the case group than in the control group (p<0.05). CONCLUSIONS: According to this study there is a correlation between the presence of B. hominis and lower anthropometric indexes in children.

Adolescent↗
PubMed2006

Ventilator-associated pneumonia in surgical emergency intensive care unit.

OBJECTIVE: To investigate the incidence, risk factors and the etiology of ventilator-associated pneumonia (VAP) in surgical emergency intensive care unit (ICU) patients. METHODS: We conducted this prospective cohort study in the surgical emergency ICU of Istanbul Medical Faculty between December 1999 and May 2001. We included 100 mechanically ventilated patients in this study. We diagnosed VAP according to the current diagnostic criteria. We identified the etiology of VAP cases by both quantitative cultures of endotracheal aspiration and blood cultures. To analyze the predisposing factors for the development of VAP, we recorded the following variables: age, gender, acute physiology and chronic health evaluation (APACHE) II score, Glasgow coma scale (GCS), sequential organ failure assessment (SOFA) score, serum albumin level, duration of mechanical ventilation (MV) prior to the development of VAP, and underlying diseases. RESULTS: We determined the VAP incidence rate as 28%. We found the APACHE II score and the duration of MV to be statistically significant variables for the development of VAP. There were no significant differences regarding age, gender, GCS, SOFA score, albumin level, or underlying diseases for the development of VAP. The isolated bacteria among VAP cases were as follows: Staphylococcus aureus (n=12, 43%), Acinetobacter spp. (n=6, 21%), coagulase-negative Staphylococci (n=4, 15%), Pseudomonas aeruginosa (n=3, 10.7%) and Klebsiella pneumoniae (n=3, 10.7%). CONCLUSION: Ventilator-associated pneumonia is a common infection, and certain interventions might affect the incidence of VAP. The ICU clinicians should be aware of the risk factors for VAP, which could prove useful in identifying patients at high risk for VAP, and modifying patient care to minimize the risk of VAP.

APACHE↗
PubMed2005

Prevalence and risk factors for HEV infection in pregnant women.

BACKGROUND: Hepatitis E is an infectious viral disease with clinical and morphological features of acute hepatitis, clinically similar to other forms of acute viral hepatitis except in pregnant women, in whom the illness is particularly severe and has a high mortality rate. The present study was conducted in western Turkey to investigate the prevalence and risk factors for HEV infection in pregnant women. MATERIAL/METHODS: The data for the study were acquired from health centers in urban and rural areas of Aydin province, Turkey. The study design was cross-sectional. Multistage sampling was used to select the study group. Samples were tested for anti-HEV IgG by commercial ELISA test. RESULTS: A total of 386 pregnant women were included in the study. Antibodies against HEV were detected in 27 of the 386 pregnant women (7.0%). The prevalence of HEV seropositivity was significantly lower (2.5%) in women with a higher education level when compared to women with a lower education level (9.7%) (p=0.023). No significant differences were identified between seropositive and seronegative women in terms of age, source of water supply and place of residence. CONCLUSIONS: According to our results, education seems to be the only factor affecting the prevalence of HEV infection in pregnant women. The prevalence rate we found was similar to the results obtained in previous community-based studies conducted in western Turkey.

Adult↗
PubMed2005

Hepatitis A and B seropositivity among medical students.

OBJECTIVE: Health science students are commonly exposed to some infectious agents, including hepatitis A virus (HAV) and hepatitis B virus (HBV), which may cause substantial morbidity and even deaths. The identification of prevalence and risk factors is essential for implementing efficacious preventive measures. A serological survey was performed among medical students of Adnan Menderes University Medical Faculty to determine the prevalence of antibodies against HAV and HBV, and, as a secondary objective, to determine risk factors for acquisition of these infections. METHODS: Nearly all students were included in the study. All participants completed a structured questionnaire that assessed demographic and socio-economic characteristics. Anti-HAV IgG, anti-HBc IgG, HbsAg and anti-HBs were tested using commercially available Elisa kits. RESULTS: A total of 247 students, 146 (59.1%) male and 101 (40.9%) female, were included in the study. The prevalence of anti-HAV IgG was detected as 64%. Number of siblings and place of residence were detected as independent factors affecting the anti-HAV seropositivity. The prevalence of anti-HBc IgG was detected as 7.3%. Among the students positive for anti-HBc IgG, 5 (2%) students were HBsAg positive and the other 13 (5.3%) were anti-HBs positive. HBV infection in household members, risky sexual behaviour and vaccination were independent factors affecting the prevalence of anti-HBc IgG positivity. CONCLUSIONS: The high susceptibility of medical students and their increased risk of clinical HAV and HBV infection identify a need for primary prevention through the administration of vaccination in this group in western Turkey.

Adolescent↗
PubMed2005

Therapeutic options for pneumococcal pneumonia in Turkey.

BACKGROUND: Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide. Streptococcus pneumoniae continues to be the most important causative agent in CAP. OBJECTIVE: This article reviews options for the empiric treatment of pneumococcal pneumonia in Turkey based on local epidemiologic data. METHODS: This was a retrospective review of studies evaluating antimicrobial susceptibility patterns among clinical isolates of S pneumoniae in Turkey from 2000 onward. Relevant studies were identified through literature searches of both Turkish (Ulakbim and Pleksus) and international (MEDLINE) databases using the search terms S pneumoniae and Turkey. Only antibiotics likely to be used in pneumococcal pneumonia were evaluated. The minimum concentration required to inhibit 90% of isolates (MIC(90)) for each antibiotic was obtained by averaging all reported values to arrive at a single value for the entire country. RESULTS: The MIC(90) for penicillin was 1 g/mL; among all isolates of S pneumoniae, 6.4% were penicillin resistant and 30.9% showed intermediate susceptibility. The MIC(90)s and overall rates of resistance (combined intermediate susceptibility and resistance) for the other antibiotics studied were as follows: cefaclor, 4 microg/mL (26.3%); cefuroxime, 2 microg/mL (15.4%); ceftriaxone, 0.25 microg/mL (0.75%); imipenem, 0.06 microg/mL (0%); erythromycin, 2 microg/mL (13.9%); clarithromycin, 2 microg/mL (13.7%); azithromycin, 2 microg/mL (13.8%); telithromycin, 0.06 microg/mL (no published breakpoints); trimethoprim-sulfamethoxazole, 4 microg/mL (63.8%); tetracycline, 16 microg/mL (24.6%); ciprofloxacin, 2 microg/mL (no published breakpoints); ofloxacin, 2 microg/mL (4%); levofloxacin, 1 microg/mL (0%); gemifloxacin, 0.06 microg/mL (no published breakpoints); and moxifloxacin, 0.06 microg/mL (0%). Penicillin G, at standard parenteral doses, has been shown to achieve concentrations above the MIC for >40% to 100% of the dosing interval, depending on the MIC of the isolate. Based on pharmacodynamic studies, the MIC(90) for penicillin in Turkey should easily be exceeded with the use of penicillin G 3 mU QID. In vitro, susceptibility is generally greater to amoxicillin than to penicillin, with average amoxicillin MIC values approximately 1 dilution lower than those for penicillin. Amoxicillin's better pharmacodynamic/pharmacokinetic properties relative to penicillin make it a reasonable option for the treatment of CAP. In pharmacodynamic studies, amoxicillin 1 g TID achieved and maintained serum concentrations of 2 to 4 microg/mL for at least 40% of the dosing interval. A new formulation of amoxicillin/clavulanate given 2000/125 mg BID is expected to eradicate isolates of S pneumoniae at an amoxicillin MIC < or = 4 microg/mL. CONCLUSIONS: Based on data from Turkish surveillance studies performed from 2000 onward, high-dose parenteral penicillin G and parenteral/oral amoxicillin may be initial choices for the empiric treatment of uncomplicated pneumococcal pneumonia in Turkey. If these agents cannot be used for any reason, other options include parenteral cefuroxime, ceftriaxone, cefotaxime, newer quinolones, macrolides, and telithromycin. Due to elevated rates of resistance in Turkey, trimethoprim-sulfamethoxazole and tetracyclines are not recommended for empiric use in these infections.

Anti-Bacterial Agents↗
PubMed2004

Susceptibility patterns of enterococci causing infections.

Enterococci are among the common organisms associated with hospital-acquired infections. We examined in vitro activities of different antibiotics to 103 enterococcal isolates. Minimal inhibitory concentrations (MICs) of penicillin G, ampicillin, gentamicin, ciprofloxacin, ofloxacin, levofloxacin, grepafloxacin, trovafloxacin and gemifloxacin were determined by broth microdilution testing method. Among the isolates 71 (69%) were identified as E. faecalis and 32 (31%) as E. faecium. While over 75% of E. faecium isolates were resistant to penicillin and ampicillin, approximately 25% of E. faecalis isolates were resistant to penicillin and ampicillin. None of the E. faecalis and E. faecium isolates were resistant to vancomycin. While 17 (52%) of E. faecium isolates exhibited high-level gentamicin resistance (HLGR), high level streptomycin resistance (HLSR) was detected in 24 (74%) of the isolates. In contrast, HLGR and HLSR rates for E. faecalis were 14 (20%) and 22 (31%), respectively. Both HLGR and HLSR were detected with higher frequency in ampicillin resistant isolates. Among fluoroquinolones, gemifloxacin and trovafloxacin were the most potent antibiotics tested. There was no increase in MIC90 values of the fluoroquinolones in ampicillin resistant isolates in comparison with ampicillin susceptible isolates. Our data suggest newer fluoroquinolones would be good alternative agents to use especially for combination drug therapy where enterococci with ampicillin resistance and HLAR are prevalent.

Anti-Bacterial Agents↗
PubMed2004

Elimination of intraluminal colonization by antibiotic lock in catheters.

Antibiotic lock (AL) technique for catheter related infection encompasses the filling of a catheter lumen with high concentrations of antibiotics for hours. The goal of AL therapy is to decontaminate the intraluminal surface of the catheter. However the duration of antibiotic therapy is not established. An in vitro model was designed to establish the time needed to eliminate intraluminal microbial colonization and to evaluate the efficacy of vancomycin in comparison with teicoplanin by using laboratory AL model. Human plasma was instilled into the catheters to allow deposition of fibrin and other products on the catheter wall. After 48 hours, the catheters were drained and inoculated with bacteria in tryptic soy broth. The catheters were then drained and filled with either (a) vancomycin saline solution (VSS) lock (b) teicoplanin saline solution (TSS) lock or (c) saline solution (SS) as the control and then incubated for 12 hours. After 12 hours incubation all the catheter were drained and filled with human plasma. Instillation of human plasma and AL was alternated every 12 hours to simulate clinical conditions. For each day three catheters, locked with VSS, TSS and SS were cultured for colony count. Microbial counts were expressed as total colony-forming units per longitudinal centimeters of catheter surface. A significant decrease in intraluminal catheter colonization started as early as day 1. At the end of 7th day catheters treated with VSS and TSS lock were completely sterile. The decrease of intraluminal colonization was similar in catheters treated with VSS and TSS lock. Also the decrease of intraluminal colonization were similar in catheter colonized with slime forming S. epidermidis and nonslime-forming S. epidermidis.

Anti-Bacterial Agents↗
PubMed2004

Effect of preventive applications on prevalence of hepatitis B virus and hepatitis C virus infections in West Turkey.

OBJECTIVE: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are community health problems in developing countries and the most common causative agents of chronic hepatitis, cirrhosis and hepatocellular carcinoma. This study investigates the prevalence and the effect of preventive applications on prevalence of HBV and HCV infections in blood donors. METHODS: Blood donors enrolled to the University and State Hospital Blood Banks in Aydin region of Turkey through the years 1993 to 2002 were retrospectively analyzed. Blood donors were investigated in 2 groups, Group I (1993-1997) and Group II (1998-2002) to compare the prevalence difference in 10-years period. Serum hepatitis B antigen (HbsAg) and anti-HCV were tested by commercially available enzyme-linked immunosorbent assay kits and anti-HCV positive results were confirmed by recombinant immune blot assays HCV test. RESULTS: The prevalence of HBV and HCV infections was determined as 1.5% and 0.19% over the period 1993-2002. Although, the prevalence of HBV infection declined significantly in Group II (1.17%) in comparison with Group I (2.27%) (p<0.0001), there was no significant difference in both groups regarding HCV infection (p=0.238). CONCLUSION: Preventive applications against blood transfusion related diseases succeed to decrease HBV infection significantly in West Turkey. Vaccination seems to be the most effective method to prevent hepatitis infection.

Adult↗
PubMed2003

Escherichia coli bind to urinary bladder epithelium through nonspecific sialic acid mediated adherence.

The first step in the bacterial colonization and infection of uropathogenic Escherichia coli is adherence to uroepithelium. Over 80% of all urinary tract infections are caused by E. coli. Uropathogenic E. coli express several adherence factors including type 1 and P fimbriae, which mediate attachment to the uroepithelium through specific binding to different glycoconjugate receptors. We showed that P and type 1 fimbriae are not the sole adhesins on uropathogenic E. coli and sialic acid also mediates nonspecific bacterial adherence of uropathogenic E. coli and urinary bladder epithelium.

Animals↗
PubMedDate not supplied

Neuraminidase produces dose-dependent decrease of slime production and adherence of slime-forming, coagulase-negative staphylococci.

BACKGROUND: Slime is one of the important structures of certain bacterial strains involved in nonspecific adherence. This study was conducted to determine the role of neuraminidase on slime formation and adherence of slime-forming coagulase-negative staphylococci to inert surface. METHODS: Quantitative biofilm and qualitative bacterial adherence assays were performed with increasing concentrations of neuraminidase extracted from Clostridium perfringens-treated bacteria in polystyrene plates and polypropylene tubes. RESULTS: Slime production of slime-forming, coagulase-negative staphylococci was significantly decreased dose dependently at > or =100 mU/mL (p <0.001). Bacterial adherence to smooth surface was impeded at > or =100 mU/mL of neuraminidase treatment and adherence results were comparable with slime production assay results. CONCLUSIONS: Sialic acid may be a constituent molecule of slime and involved in bacterial adherence to inert surface. These results represent new insight into the mechanism of slime production and adherence of slime-forming, coagulase-negative staphylococci to inert surface.

Animals↗