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Although the availability of effective antimicrobial therapy, both otitis media with effusion (OME) and acute bacterial meningitis (ABM) are still important infections for children, leading serious health problems. The most frequently isolated bacteria from cerebrospinal fluid (CSF) of ABM patients are Haemophilus influenzae type b, Neisseria meningitidis and Streptococcus pneumoniae, and middle ear effusion (MEE) samples of OME patients are H. influenzae, S. pneumoniae, Moraxella catarrhalis, respectively. Since they are fastidious bacteria, various problems may arise in the rapid diagnosis in both ABM and OME settings. In this study, the diagnostic value of polymerase chain reaction (PCR) has been searched for the detection of bacterial DNA in CSF and MEE specimens and evaluated in comparison to conventional culture method accepted as the "gold standard". A total of 75 samples (53 CSF, 22 MEE) collected from meningitis and OME suspected children were included in the study. With the conventional culture method, one S. pneumoniae strain was isolated from a CSF sample, and one H. influenzae (non-type b) and two M. catarrhalis strains were isolated from three of MEE samples (total isolation rate: %5.3; 4/75). Standard PCR protocol was applied for the detection of H. influenzae, while multiplex PCR protocol was used for M. catarrhalis and S. pneumoniae, since H. influenzae and S. pneumoniae amplification products were of similar size. PCR revealed genomic DNA sequences of S. pneumoniae from five of the CSF samples, while three H. influenzae, three M. catarrhalis and two S. pneumoniae+M. catarrhalis were detected from MEE samples (total detection rate: %17.3; 13/75). Sensitivity and specificity rates of PCR method were found as 100% and 92.3% for CSF samples, and 100% and 73.7% for MEE samples, respectively, with a total sensitivity of 100%, specificity of 87.3%, positive predictive value of 30.8%, and negative predictive value of 100%. As a result it was concluded that PCR method could be considered as a rapid, reliable and feasible method for the detection of the most common fastidious bacteria that lead to meningitis and OME.

Candida albicans has the most important place among fungal agents causing systemic infections. Molecular epidemiologic methods, especially pulsed-field gel electrophoresis (PFGE) are used frequently for outbreak investigations and to reveal existing clones in hospital environment. In this study, from 2000 through 2003, 42 C. albicans strains, isolated from the patients with nosocomial fungemia, were genotyped by PFGE. The results revealed that 31 different karyotypes existed among the study population. In conclusion, these C. albicans strains which were isolated in our hospital during the study period were not clonally related, whereas they were most probably arising from endogenous sources. It might be emphasized that the combination of PFGE method with a secondary method would be very useful to improve its discriminatory power although PFGE alone gives highly reproducible results.

Investigation of the genetic relationship of the three Candida albicans strains isolated from each of two patients, one with C. albicans meningitis and the other with pancreatic pseudocyst (PP), by PFGE (pulsed-field gel electrophoresis), was aimed in this study. Three strains of C. albicans isolated from bloodstream, abscess and drainage fluid of the patient with PP were found to show the same karyotype, while three strains of C. albicans from cerebrospinal fluid, nasopharyngeal swab culture and stool sample of the patient with meningitis were found closely related. As a conclusion, PFGE enables to give valuable information about the probable source of transmission on individual basis in these two invasive candida infections.

Pseudomonas aeruginosa is one of the important cause of infections in intensive care unit (ICU) patients. The aim of this study was to investigate the effectiveness of ertapenem prior to its use in Turkey, against multiple-resistant P. aeruginosa strains isolated from ICUs. Susceptibility tests were performed by using Kirby-Bauer disk diffusion method and MicroScan MERCH MIC 8 panel (MicroScan 96, Dade Behring, USA). While the resistance rates of ertapenem, imipenem and meropenem were 59.2%, 50% and 48.1% by disk diffusion method, they were 57.4%, 46.2% and 42.5% by MicroScan, respectively. Ertapenem was found less effective against multiple-resistant P. aeruginosa isolates by both of the methods when compared with imipenem and meropenem. Piperacillin/tazobactam was detected as the most effective agent against these isolates by both of the methods. As a result, although carbapenems are frequently used for infections caused by P. aeruginosa, ertapenem, which is a new carbapenem, is not effective as much as the others. In case of confirmation of our results by larger scale studies, the empiric treatment of ICU infections caused by P. aeruginosa with ertapenem, should be carefully evaluated.

Plasmid profile analysis (PPA), random amplification of polymorphic DNA (RAPD) and pulsed field gel electrophoresis (PFGE) are the three most valuable epidemiological tools for genotyping of methicillin resistant Staphylococcus aureus (MRSA) strains. Aim of this study was to evaluate these three methods in respect to their cost, reproducibility, and discriminatory power. Eighty one nosocomial MRSA isolates with unknown genetic and epidemiological relatedness from Training Hospital of Gulhane Military Medical School, were genotyped by PPA, RAPD, and PFGE methods. All isolates (100%) were typed by RAPD and PFGE, however, eight (9.9%) isolates could not be typed by PPA since they lacked plasmid DNA. Reproducibilities of all the three methods were found to be 100 percent. Discriminatory powers of PPA, RAPD and PFGE methods were calculated as 48.6%, 61.1% and 80.1%, respectively. In conclusion, out of the three methods tested, PFGE allowed the most effective discrimination of MRSA strains. However, PFGE was more time consuming and technically demanding, and required use of specialized and expensive equipment. Although PPA and RAPD were less discriminatory than PFGE, these methods were technically simple, rapid and cheaper. When PPA and RAPD were used in combination, they had equal discriminatory power to PFGE. Thus, it should be emphasized that PPA and RAPD methods could be preferred for initial screening purposes while PFGE should be used as a confirmatory test in genotyping of MRSA isolates.

Macrolide resistance in group A beta hemolytic streptococci (GABHS) have been reported with increasing frequency from various geographic regions in the world, and for the respective treatment alternatives and epidemiologic studies, macrolide resistance rates and phenotypes have been determined. In this study erythromycin, clarithromycin and azithromycin were tested with disc diffusion method against 560 GABHS, isolated from the throat samples collected between 1999-2002. NCCLS guidelines were followed for the susceptibility tests and MIC values were obtained by E-Test in resistant isolates. For determining the resistance phenotype, erythromycin and clindamycin discs were used. Only one isolate (0.27%) was found intermediately resistant to erythromycin, and clarithromycin, and resistant to azithromycin between May 1999-January 2000, whereas in the period between January 2001-June 2002, one isolate (%0.5) was found susceptible to erythromycin and clarithromycin, but intermediately resistant to azithromycin. In each period three isolates (0.83% and 1.5%, respectively) were found to be resistant to all the tested macrolides. There was no statistically significant difference between the resistance rates in these periods. Three of the resistant isolates had inducible type, and the other five isolates had M phenotype macrolide resistance. Testing for macrolide susceptibilities and screening the resistance phenotypes have crucial importance in case of GABHS infections, since these can be taken into consideration for epidemiological issues as well as a guide for empirical treatment protocols in any geographical setting, as well as in our country.

Tetanus is a preventable disease that continues to affect people in both developing and developed countries. The aim of the present study was to evaluate the immunity profile to tetanus in patients with Type II diabetes mellitus (DM) and to compare them with healthy controls. The tetanus antitoxin levels in 310 diabetic patients (104 males and 206 females) and in 200 healthy controls (72 males and 128 females) were measured by ELISA (Virotech, Germany). The mean antitoxin concentration in patient and control groups were 0.8238+/-1.61 and 0.9978+/-1.49 IU/ml, respectively. There was a statistically significant difference between the two groups (z=-3.520, P=.0001 and odds ratio was 2.367). There was a definitive inverse correlation between the duration of diabetes and tetanus antibody titers (Spearman's correlation analysis, r=-.155, P=.006). A gender-dependent difference in the susceptibility to tetanus was present in the diabetic group with antibody titers being significantly higher in males compared with females (z=-2.267, P=.023). For both of control (chi(2)=20.207, P=.003) and patient (chi(2)=43.532, P=.0001) groups, there was a significant inverse correlation between the tetanus immunity levels and age. Statistically, a significant drop in antibody titers of both groups was found as the period past from the last immunization increased (Pearson correlation analysis: for patient group r=-.364, P=.0001; for control group r=-.143, P=.044). The tetanus antitoxin levels were significantly increased in individuals who had primary immunization during childhood (for patient group chi(2)=17.191, P=.0001; for control group chi(2)=9.911, P=.007). A significant reduction in the level of antitoxin immunity to tetanus in association with an increased susceptibility to infections in patients with diabetes may implicate the need for improving vaccination rates in this patient group.

There has been an increasing multiple drug resistance problem in Vibrio cholerae biotype Eltor, the causative agent of 7th pandemic. The aim of this study was to show in vitro and in vivo susceptibility and effectiveness of quinolones in the treatment of endemic cholera cases. Excellent results were obtained in 53 bacteriologically confirmed cholera patients treated with short-term ofloxacin and ciprofloxacin. To our knowledge, there has been no previous report on this subject in the international medical literature. Our results show that quinolones can be an alternative drug for the treatment of multiply resistant V. cholerae infections.

The prevalence of Cryptosporidium sp. was investigated in fecal specimens from 106 patients with neoplasia and diarrhea (74 females, 32 males) by using Ziehl-Neelsen and Giemsa stains. Oocystic forms of Cryptosporidium sp. were found in 18 (17%) of these patients. No oocystic form of Cryptosporidium sp. was detected in the control group of 60 patients with neoplasia (37 females, 23 males) but without diarrhea. The frequent findings of Cryptosporidium sp. in patients with neoplasia and diarrhea who are undergoing chemotherapy indicates that a search for this organism is justified.