[Establishment of an algorithm for serological testing of syphilis identification]. / Sifiliz tanisinda kullanilan serolojik testler için akis semasinin olusturulmasi.

Serological methods are widely used for the laboratory diagnosis of syphilis or for screening purposes. The aim of this study was to determine an algorithm for the application of laboratory tests that will provide accurate diagnosis of syphilis in a cheap, fast and practical way. A total of 162 serum samples were evaluated by the following tests: VDRL (Venereal Disease Research Laboratory; Omega Diagnostic, UK), TPHA (Treponema pallidum Hemagglutination Test; Omega Diagnostic, UK), ELISA IgG + IgM (Enzyme Linked Immunosorbent Assay; DiaPro Diagnostic Bioprobes, Italy), FTA-ABS (Fluorescent Treponemal Antibody-Absorption; IgG, Euroimmun, Germany) and WB (Western Blot; IgG Euroimmun, Germany). When the gold standard was considered as FTA-ABS test, the sensitivity, specificity, positive and negative predictive values for VDRL were 77.1%, 100% 100% an 80.6%; for TPHA were 92.8%, 98.7%, 98.7% and 92.9%, for ELISA 98.8%, 98.7%, 98.8% and 98.7%, and for WB 98.8%, 100%, 100% and 98.7%, respectively. When the results of screening with VDRL together with TPHA were compared with FTA-ABS, it was observed that if both VDRL and TPHA results were positive, then there was 100% concordance between the tests. However, when both of the test results were negative, 1.3% of them yielded positive result with FTA-ABS. If either one of VDRL or TPHA results were positive (n = 24), 95.8% (n = 23) was positive with FTA-ABS. Therefore, inconsistent results obtained by VDRL and TPHA requires verification by another method. When ELISA or WB tests were used, the borderline results need verification, however, positive or negative results would be reported. The determination of an algorithm for laboratory tests also depend on the number of patients, cost, cost per positive patient and workload of the laboratory. Thus, ELISA could be selected when the number of cases is high and the results should be reported unless they are suspicious. When the number of cases is low, VDRL/TPHA should be selected, and the results should be verified if they are inconsistent. However, the demographic characteristics of patient groups are also important in test selection and work flow. False positive results are troublesome in case of marriage pre-screening and false negative results in sex workers. When all these factors are taken into consideration it may be suggested that either ELISA or VDRL together with TPHA should be performed and the results should be confirmed by a reference test in case of borderline results in ELISA or inconsistency between VDRL and TPHA results. Although screening for syphilis in the setting of blood banking is a matter of debate, if it is to be performed, then ELISA would be better since the work load is high. In case of pregnancy inconsistent VDRL and TPHA results should be verified since no risk could be afforded.

[Investigation of herpes simplex virus in viral meningoencephalitis suspected cases using molecular and serological methods]. / Viral meningoensefalit süpheli hastalarda herpes simpleks virusunun moleküler ve serolojik yöntemlerle arastirilmasi.

Herpes simplex virus (HSV) meningoencephalitis has a high mortality rate if proper antiviral therapy is not applied. Thus rapid diagnosis is of peculiar importance in such cases. In this study we aimed to evaluate the use of polymerase chain reaction (PCR) and detection of intrathecally synthesized antibodies by serological methods in viral meningoencephalitis suspected cases to determine HSV as the causative agent. Seventeen cases with cerebrospinal fluid (CSF) samples with microscopical and biochemical findings compatible with viral encephalitis were included in this study. CSF samples yielded no bacterial growth. Cell cultures propagated in Vero cell line and PCR with different primer sets against HSV-1 and HSV-2 (specific for US7 and US2 gene regions, respectively) were used to investigate the presence of HSV in CSF. Serum samples were taken simultaneously with the CSF sampling and "Reibergram" graphics and antibody index (AI) calculations were used for the evaluation of intrathecal antibody synthesis. Albumin and total IgG levels in serum and CSF samples measured with nephelometry (Dade-Behring, Germany) for Reibergram graphics, albumin and IgG ratios were calculated. Quantitative levels of HSV 1+2 IgG were measured in serum and CSF samples using ELISA (HSV-1/2 Pool; Antibody Determination in CSF, Euroimmun, Germany) for AI determination. One of the CSF samples obtained one week after the neurological symptoms had started, yielded HSV-2 in cell culture and also HSV-2 DNA was detected by PCR. Intrathecal antibody synthesis was not detected in this case. In two cases with symptoms lasting for more than three weeks, intrathecal IgG synthesis in Reibergrams and pathological intrathecal HSV AI (27.9 and 7.9, respectively) were detected, however, virus isolation and PCR detection were not successful. For the other 14 cases, HSV-DNA were found negative and no intrathecal antibody synthesis were detected. HSV meningoencephalitis can be diagnosed via using PCR which has been accepted as gold standard in recent years, with 24 hours turn-around time. However, if CSF samples were taken later than the first week following the beginning of symptoms, possibility of HSV detection by PCR is lowered. According to the data obtained from this limited study, it may be suggested that PCR may be used for the detection of HSV-DNA in CSF samples during the early phase of meningoencephalitis cases, however, consideration must be taken to detect the intrathecal antibodies during the later phases of the infection where intrathecal antibody synthesis starts.

Co-trimoxazole and quinolone resistance in Escherichia coli isolated from urinary tract infections over the last 10 years.

Over the last 10 years the treatment of choice for urinary tract infections (UTIs) in Turkey has changed from co-trimoxazole to quinolones owing to the rate of resistance to co-trimoxazole and its high level of therapeutic failure. The resistance ratio of 1939 UTI Escherichia coli from outpatients (1994-2003) was evaluated by Kirby-Bauer disc diffusion method for the aforementioned antibiotics to determine the change in resistance. The co-trimoxazole resistance ratio decreased during this period, with the highest ratio in 1996 (69.3%) and the lowest ratio in 2003 (38.5%) (P < 0.001). The lowest resistance ratios occurred in 1995 (4.1%) for ofloxacin and in 1996 (5.2%) for ciprofloxacin, and the highest resistance ratios occurred in 2002 (25.3% and 27.6%) for ofloxacin and ciprofloxacin, respectively (P < 0.001, P < 0.001). These findings emphasise that antibiotic usage policies, especially empirical therapies, should be based on antimicrobial resistance surveillance studies.

[Epidemiological evaluation of a possible outbreak in and nearby Tokat province]. / Tokat ili ve çevresinde saptanan olasi bir salginin epidemiyolojik yönden degerlendirmesi.

Between the dates of May 4th-August 6th 2002, 46 cases were detected with abdominal pain nausea, vomiting, arthralgia/myalgia, headache, fever, diarrhea and rash, in the middle Blacksea and north inner Anatolia regions. Their laboratory findings yielded elevated levels of liver enzymes (AST, ALT, LDH), leucopenia and thrombocytopenia. As the infection was treated easily with tetracyclines, clinical diagnosis was considered to be rickettsiosis or ehrlichiosis. Serum and blood samples obtained from some of the patients were tested against Rickettsia, Ehrlichia, Leptospira and Coxiella, in the national and international laboratories. Samples from 19 patients were sent to National Reference Centre and WHO Collaborating Centre for Rickettsial Reference and Research Laboratory, France, and 7 of them were reported as acute Q fever while 8 of them were reported as passed Q fever (QF) cases. In May 2003, new cases with similar symptoms have been reported from the same regions, with different epidemiologic and serologic findings (tick exposure history was higher, response to tetracycline was lower, C. burnetii antibodies were negative), indicating a viral etiology. The samples of these patients have been sent to National Reference Centre and WHO Collaborating Centre for Arboviruses and Viral Heamorrhagic Fevers, France, and the initial reports were marked as Crimean Congo hemorrhagic fever virus (CCHFV). Then the serum samples of previous 26 patients which were stored in National Serum Bank have been retrospectively investigated for viral aetiology in the same center, and 17 of them have been found positive for CCHFV IgM antibodies. Four of these patients were diagnosed as acute QF in 2002, one was passed QF, 2 were negative for QF and 10 were patients not investigated for QF. As a result, the detection of the both infections together in the same area shows the essential need for further epidemiological investigations.

Antimicrobial susceptibility testing of Campylobacter jejuni: a comparison between Etest and agar dilution method.

The susceptibility of Campylobacter jejuni strains (n = 50) against nine antimicrobials were determined in comparison with Etest (AB BIODISK, Solna, Sweden) and agar dilution method to further investigate the correlation between the two methods. All the strains were isolated from stool samples of patients with diarrhea in 1998 and found to be highly susceptible (>84%) to ampicillin, tetracycline, gentamicin, chloramphenicol, ciprofloxacin and erythromycin. The essential agreement between two methods was 66.6% (+/-1 log(2) dilution) and 85.5% (+/-2 log(2) dilution). The agreement of susceptibility categories was higher at 94.4%.