Suat Saribas

Higher prevalence of toxoplasmosis in victims of traffic accidents suggest increased risk of traffic accident in Toxoplasma-infected inhabitants of Istanbul and its suburbs ☆

Reflexes of drivers who have toxoplasmosis have been shown to deteriorate from the actions of the parasitic cysts. The cysts can change the level of the neurotransmitters such as dopamine in the brain and by doing so extend the muscle response time and change personality profiles. In this study, we aimed to determine the frequency of the latent toxoplasmosis (LT) in the driver population who were either injured or died in traffic accidents reported in Istanbul and its suburbs. We compared the results with a control group and discussed the relationship between the LT and the traffic accidents. We included 218 (89.7%) non-fatal, 25 (10.3%) fatal cases in our study as study groups. A total 243 subjects, 234 (96%) male, 9 (4%) female (who were alcohol negative) compared with 191 (95.5%) male and 9 (4.5%) female subjects (control group) who had a traffic accident before but no history of toxoplasmosis were studied. Serologic tests, enzyme immunoassay (EIA) for IgG and IgM, and microimmunoflorescence (MIF) for IgG were used as the reference test, the Sabin-Feldman Dye test (SFDT) was used. According to serologic test results, LT seroprevalence in the study groups was 130 (53.5%) and in the control group 56 (28%) (p<0.0001). A LT was present in 126 out of 234 (53.8%) males in the study groups, and 54 out of 191 (28.3%) males in the control group (p<0.0001). In the 31-44 year age group, there was a significant difference with regard to toxoplasmosis between the study subjects and control groups (p<0.0001). This difference was statistically very significant in (recent and former) cases with middle-aged men (31-44 years old). The results of this retrospective study suggest that LT in drivers, especially those who are between 31 and 44 years might increase the risk for getting involved in a car accident. In a prospective study, Toxoplasma positive and negative subjects can be monitored before they are involved in a traffic accident to clarify the cause and result relationship.

Do infections trigger juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is a disease that was prominent with increased inflammation response in immune system, appeared mostly with peripheral arthritis and endogenous and exogenous antigens play a role in the pathogenesis of disease. Two major reasons were thinking to be considerably important. First of them is immunological predisposition and the second one is environmental factors. Infections are considered to be the most important between environmental factors but also stress and trauma are also important in the etiology of the disease. However, the relation between JIA and infections is not clearly defined but the relation between adult chronic arthritis and infections was well-defined. A total of 70 patients, 26 with primer JIA, 20 with recurrent JIA, 24 healthy control were included in this study. Mycoplasma pneumoniae, Chlamydophila pneumoniae and C. Jejuni were detected in 4, 1 and 1 of 10 (38.46%) patients with primer JIA, respectively. Salmonella enteritidis, EBV, M. pneumoniae, C. jejuni and Borrelia burgdorferi were detected in 1, 2, 2, 2, and 1 of the 8(40%) patients with recurrent JIA, respectively. S. enteritidis were isolated in feces culture and also identified by agglutination method. Infection was detected in total 18 (39.13%) of patient groups. C. pneumoniae and C. jejuni were detected in 1 and 1 of 2(8.33) healthy control groups, respectively. Throat culture positivity was not detected in any of the patient and healthy control groups. In conclusion, etiopathogenesis of JIA is not clearly understood and suggested that various factors can trigger the disease and it is the most common rheumatoid disease of childhood. However, there are some studies focusing especially on one infectious agent but this is the first study including such a big range of infectious agents in the literature for the microorganisms that can be suggested to have a role in the etiopathogenesis of JIA. We have a conclusion in the light of our results and suggest that some microorganisms can trigger and increase the intensity of clinical situation according to the case. When we evaluate the primer and recurrent JIA groups; M. pneumoniae and C. jejuni come forward and seen common in JIA cases. We also suggest that the pre-diagnosis of microorganisms, which can play a role as primarily or by intervening in the etiopathogenesis of JIA and adding specific antimicrobial therapy to the standard JIA therapy, it is possible to perform new, extended, especially molecular based serial case studies.

Vancomycin Tolerance in Enterococci

Background: Tolerance can be defined as the ability of bacteria to grow in the presence of high concentrations of bactericide antimicrobics, so that the killing action of the drug is avoided but the minimal inhibitory concentration (MIC) remains the same. We investigated vancomycin tolerance in the Enterococcus faecium and Enterococcus faecalis strains isolated from different clinical specimens. Methods: Vancomycin was obtained from Sigma Chemical Co. We studied 100 enterococci strains. Fifty-six and 44 of Enterococcus strains were idendified as E. feacalis and E. faecium, respectively. To determine MICs and minimal bactericidal concentration (MBC), we inoculated strains from an overnight agar culture to Müller-Hinton broth and incubated them for 4–6 h at 37°C with shaking to obtain a logarithmic phase culture. The inoculum was controlled by performing a colony count for each test. We determined MBC values and MBC/MIC ratios to study tolerance to vancomycin. Vancomycin tolerance was defined as a high MBC value and an MBC/MIC ratio ≧32. Results: Fifty-six and 44 of the Enterococcus strains were identified as E. faecium and E. faecalis, respectively. Thirty-one E. faecium and 48 E. faecalis were found to be susceptible to vancomycin and these susceptible strains were included in this study. The MICs of susceptible strains ranged from ≤1 to 4 mg/l, the MBCs were ≧512 mg/l. Tolerance was detected in all E. faecalis and E. faecium strains. The standard E. faecalis 21913 strain also exhibited tolerance according to the high MBC value and the MBC/MIC ratio. We defined the tolerant strains as having no bactericidal effect and MBC/MIC ≧32. We found that a 100% tolerance was present in susceptible strains. Conclusions: One of the hypotheses for tolerance is that tolerant cells fail to mobilize or create the autolysins needed for enlargement and division. Our data suggests that tolerance may compromise glycopeptide therapy of serious enterococci infections. To add an aminoglycoside to the glycopeptide therapy unless MBCs are unavailable can be useful in the effective treatment of serious Enterococcus infections.

The relationship between arthritis and human parvovirus B19 infection

In order to evaluate the role of human parvovirus B19 in the etiopathogenesis of autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), synovial fluid and blood specimens were collected at 1-month intervals from 20 patients with early synovitis (ES) and 31 with RA. Blood specimens were also collected from 25 patients with SLE, 25 with osteoarthritis (OA) as the diseased control group, and 50 healthy blood donors (HBD) as the healthy control group. Detection of B19 IgM and B19 IgG were performed by enzyme-linked immunosorbent assay from serum specimens, and B19 DNA was detected by polymerase chain reaction from synovial fluid samples. B19 IgM, B19 IgG, and B19 DNA were found in the three patients of the ES group. Subsequently, two of them were diagnosed with RA and one with SLE. B19 DNA was also detected in the synovial fluid of eight patients in the RA group. Of them, all were positive for B19 IgG and half were positive for B19 IgM. B19 IgM was not detected in either of the control groups. To define the role of B19 in the etiopathogenesis and prognosis of undiagnosed arthritis and other chronic inflammatory diseases such as RA and SLE, we need broader serial and prospective studies based on clinical and laboratory collaboration. In conjunction with case reports, these studies would also serve to detect other possible factors in the etiopathogenesis of chronic inflammatory diseases.

Are isolated anti-HBc blood donors in high risk group? The detection of HBV DNA in isolated anti-HBc cases with nucleic acid amplification test (NAT) based on transcription-mediated amplification (TMA) and HBV discrimination

AIM Hepatitis B virus (HBV) can be transmitted by blood transfusions even so using serological tests having high sensitivity and specificity. We aimed to detect HBV DNA in isolated Anti-HBc donors and show if they have transfusion risk or not. METHOD We investigated Anti-Hbc and Anti-HBs in serum samples of 12858 HBs-Ag negative blood donors who were applied to the Turkish Redcrescent between June 2007 and October 2008 by the Micro ELISA kit (Hepanostica ultra HBsAg, Bio Meriux, France). Anti-HBc and Anti-Hbs positive cases were omitted. We used Procleix ultrio (Chiro, USA) test kit (Chiron Tigris automated instrument was used) based TMA (Transcription-Mediated Amplification) for NAT study in Anti-HBc positive and Anti-HBs negative plasma samples. The discrimination of HBV in NAT positive samples were performed by Procleix Discrimination (Chiro, USA) test. RESULTS 2748 (21.4%) Anti-HBc seropositivity were detected in 12852 HBsAg(-) serum samples. 23.5% Anti-HBs negativity was detected in 2748 Anti-HBc positive serum samples. On the other hand, 5.1% isolated Anti-Hbc positivity [HBsAg(-), Anti-HBc(+), Anti-HBs(-)] were detected in 12852 HBsAg(-) serum samples. 0.091% and 0.047% HBV-DNA positivity were detected in isolated Anti-HBc positive plasma samples and HBsAg(-) plasma samples, respectively. CONCLUSION As a result, even we have detected one HBV transmission in every 2142 blood transfusion by HBsAg screening tests; we suggest that it is not necessary to add additional tests to detect isolated Anti-HBc for routine purposes in Blood Banking. The reasons are higher negativity rates (99%) of isolated Anti-HBc serum samples and the rejection of blood donors with Anti-HBc positivity.

Antimicrobial resistance of Helicobacter pylori strains to five antibiotics, including levofloxacin, in Northwestern Turkey

INTRODUCTION Antibiotic resistance is the main factor that affects the efficacy of current therapeutic regimens against Helicobacter pylori. This study aimed to determine the rates of resistance to efficacy clarithromycin, amoxicillin, tetracycline, levofloxacin and metronidazole among H. pylori strains isolated from Turkish patients with dyspepsia. METHODS H. pylori was cultured from corpus and antrum biopsies that were collected from patients with dyspeptic symptoms, and the antimicrobial susceptibility of H. pylori was determined using the E-test (clarithromycin, amoxicillin, tetracycline, metronidazole and levofloxacin) according to the EUCAST breakpoints. Point mutations in the 23S rRNA gene of clarithromycin-resistant strains were investigated using real-time PCR. RESULTS A total of 98 H. pylori strains were isolated, all of which were susceptible to amoxicillin and tetracycline. Of these strains, 36.7% (36/98) were resistant to clarithromycin, 35.5% (34/98) were resistant to metronidazole, and 29.5% (29/98) were resistant to levofloxacin. Multiple resistance was detected in 19.3% of the isolates. The A2143G and A2144G point mutations in the 23S rRNA-encoding gene were found in all 36 (100%) of the clarithromycin-resistant strains. Additionally, the levofloxacin MIC values increased to 32 mg/L in our H. pylori strains. Finally, among the clarithromycin-resistant strains, 27.2% were resistant to levofloxacin, and 45.4% were resistant to metronidazole. CONCLUSIONS We conclude that treatment failure after clarithromycin- or levofloxacin-based triple therapy is not surprising and that metronidazole is not a reliable agent for the eradication of H. pylori infection in Turkey.

The detection of occult HBV infection in patients with HBsAg negative pattern by real-time PCR method

AIM Diagnostic problems may be encountered in Hepatitis B virus (HBV) infections by serological tests and HBV DNA can be detectable in plasma and liver tissue while the HBsAg test is negative. This situation can be defined as occult or isolated Anti-HBc infections. Occult HBV infections may be divided into two categories by using hepatitis markers. One of them being that all hepatitis markers are negative and the other situation is having Anti-HBc +/- and Anti-HBs+patterns. These situations can be seen in isolated Anti-HBc cases. METHOD In this study, we aimed to detect the ratio of occult HBV infections by investigating HBV DNA in four different groups. These groups are: (1) 20 isolated Anti-HBc positive individuals, (2) 23 individuals naturally immune to HBV infection, (3) 20 individuals with seronegative hepatitis markers and high ALT levels, and (4) 23 vaccinated individuals against HBV. In order to detect HBV DNA the real-time PCR kit (QIAGEN, Artus HBV RG PCR Kit, Germany) with high analytical sensitivity (≤3.8IU/ml) was used. RESULTS The reliability of the molecular methods was assessed by increasing the quantitation standards of internal, external and also positive controls. No HBV DNA was detected in any of the 86 individuals consisting of four study groups. CONCLUSION In conclusion, we did not detect occult HBV infection in our four study groups by using a high sensitivity real-time (RT) PCR method, while occult HBV infections with various frequencies were detected in other large, serial international studies in which highly sensitive analytical molecular methods were used. Although we also used a high standard molecular kit to detect occult HBV infections, we suggest that the reason for the absence of detection of occult HBV infections may be due to the small number of cases included in this study. However, it was assumed that the use of a nucleic acid amplification technology (NAT) with high analytical sensitivity in blood banks to prevent HBV transmission by blood transfusion is controversial due to both costs and diagnostic efficacy and for this reason we suggest that it will be useful to perform large serial studies regarding occult HBV infections in the future.

New approaches to in vitro diagnosis of hepatitis C infection a reason for post transfusion hepatitis: Diagnostic value of determination of hepatitis C virus core antigen

In between the dates of February 2008-March 2009, by applying to Istanbul University CTF Microbiology and Clinical Microbiology Basic Sciences Branch and Duzen laboratories, 123 cases, where HCV RNA and anti-HCV positivity are identified with molecular (real-time PCR) and serologic (ELISA) methods as a positive control group, and 48 cases where HCV RNA and anti-HCV negativity are identified as a negative control group are established. The values of sensitivity, specificity, positive and negative approximation of recently developed HCV Core Ag (Abbott Diagnostics, Germany) kit are determined successively as 94.3%, 97.9%, 99.1%, 87%, 95.3% and 88%. Although the new HCV Ag assay is clearly not sensitive enough to replace HCV NAT it may serve as a valuable tool in the HCV diagnostic algorithm as it is able to pick up a great majority of anti-HCV and HCV RNA positive samples, thus allowing a timely and less expensive serological diagnosis of an active HCV infection. This may be an advantage for labs that do not have access to PCR easily.

Neopterin and Soluble CD14 Levels as Indicators of Immune Activation in Cases with Indeterminate Pattern and True Positive HIV-1 Infection

Background We aimed to evaluate the roles of the plasma immune activation biomarkers neopterin and soluble CD14 (sCD14) in the indirect assessment of the immune activation status of patients with the indeterminate HIV-1 (IHIV-1) pattern and a true HIV-1-positive infection (PCG). Methods This cross-sectional and descriptive study included eighty-eight patients with the IHIV-1 pattern, 100 patients in the PCG, and 100 people in a healthy control group (HCG). Neopterin and sCD14 levels were determined by competitive and sandwich ELISA methods, respectively. Results Mean neopterin and sCD14 levels among those with the IHIV-1 pattern were significantly lower than among the PCG (p < 0.001 and p = 0.001, respectively), but they were similiar to those in the HCG (p = 0.57 and p = 0.66, respectively. Mean neopterin and sCD14 levels among the PCG were found to be significantly higher than among those with the IHIV-1 pattern (p < 0.001 and p = 0.001, respectively) and among those in the HCG (p = 0.001, p < 0.001, respectively). Neopterin did not have adequate predictive value for identifying those in the PCG (area under the curve [AUC] = 0.534; 95% CI, 0.463–0.605; p = 0.4256); sCD14 also had poor predictive value but high specificity (100%) for identifying those in the PCG (AUC = 0.627; 95% CI, 0.556–0.694; p = 0.0036). Conclusions While low levels of these two biomarkers were detected among those with the IHIV-1 pattern, they were found in high levels among those in the PCG. These two markers obviously cannot be used as a sceening test because they have low sensitivies. Taken together, we suggest that neopterin and sCD14 may be helpful because they both have high specificity (92%-100%) as indirect non-specific markers for predicting the immune activation status of individuals, whether or not they have true positive HIV-1.

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.