Determination of amphotericin B antifungal susceptibility in Candida strains using an inverted microscope.

INTRODUCTION: Invasive Candida infections have recently shown a significant increase in prevalence and are associated with high mortality rates. Initiating early antifungal treatment in patients with candidemia is vital. The aim of our study was to compare the antifungal susceptibility results of a new method called Flat Plate Method modified from reference "Clinical and Laboratory Standards Institute (CLSI) microdilution method by us with Sensitititre Yeast One colorimetric method and the reference CLSI method. METHODOLOGY: We tested 100 Candida isolates from blood cultures. We followed the CLSI M27-A3 (reference method for broth dilution antifungal susceptibility testing of yeasts; third edition) guidelines for testing in vitro susceptibility to amphotericin B. In the Flat Plate method, 96-well plates were used for evaluation with an inverted microscope. Minimum inhibitory concentration (MIC) values in the SYO method were measured following the manufacturer's instructions. The MIC values obtained by all three methods were considered compatible if they were within ± 2 dilution limits. RESULTS: The SYO method detected C. albicans and C. glabrata with 100% essential agreement, whereas there was 96.29% essential agreement in the case of C. parapsilosis. In the Flat Plate method, the essential agreement with amphotericin B was 91.42%, for C. albicans isolates and 89.47%.for C. glabrata strains. CONCLUSIONS: When determining early antifungal susceptibility using the Flat Plate method, the results are obtained quickly, with high accuracy, and without incurring additional costs. However, there is a need for comprehensive studies comparing different antifungals.

Effect of antinuclear antibody positivity on antineutrophil cytoplasmic antibody results by indirect immunofluorescence assay.

BACKGROUND: The indirect immunofluorescence assay (IIFA) utilizing antineutrophil cytoplasmic antibodies (ANCA) is widely used as a diagnostic test for autoimmune vasculitis. The presence of antinuclear antibodies (ANA) might lead to a misleading interpretation of ANCA. This study aims to explore the impact of the presence of ANA on the interpretation of ANCA. METHODS: This retrospective research examined samples negative for antiMPO and antiPR3 ANCA by IIFA and explored correlations between the ANA-IIFA results and the ANCA interpretation frequencies. Our analysis involved the use of suitable statistical methods, including Chi-square and kappa statistics. RESULTS: Up to 75.2% of the ANCA-IIFA-positive samples exhibited a positive p-ANCA pattern when using the ethanol-fixed substrate, with c-ANCA positivity at 24.8%. In the ANA-IIFA-positive samples, ~77.3% displayed p-ANCA patterns on ethanol-fixed substrates. A comparison between the ANA-IIFA titers and the p-ANCA results revealed that p-ANCA positivity was notably more common in samples with higher titers, and this correlation was found to be statistically significant. CONCLUSION: Positive ANA results by IIFA tests are linked to a higher incidence of p-ANCA interpretation, particularly in cases with higher titer patterns. This insight aids laboratories in establishing effective workflows to investigate potential p-ANCA interference.

Molecular epidemiology of Coxiella burnetii detected in humans and domestic ruminants in Turkey.

Q fever is a zoonotic disease that is known to be widespread throughout the world by many researches since its discovery in 1935 and it is important in terms of animal and public health. Coxiella burnetii, which is the etiological agent of the disease, is an obligate intracellular pathogen. While the disease generally manifests itself with abortion in animals, disease manifests as atypical pneumonia or granulomatous hepatitis in the acute form and as endocarditis in the chronic form in humans. Its presence in Turkey has been shown with a large number of studies. The aim of this study was to show the genotypic relationship with MLVA analysis of C. burnetii samples found in cattle, sheep and goat samples in Erzurum and Samsun Veterinary Control Institutes and blood samples collected from humans with atypical pneumonia findings. In the study, MLVA analyses of 100 positive samples from 50 cows, 41 sheep and 9 goats from Northeast Anatolia and Black Sea regions and C. burnetii positive samples found in 6 individuals with atypical pneumonia were performed. As a result of the study, it was found that 106 C. burnetii samples had belong to 16 genotype groups. It was found that genotype XVI was the most prevalent among these groups and it was seen in both regions. In addition to this, genotype IX profile was the second largest group with 83.3% (5/6) of human samples. In this study, the genotypes common in the regions were determined and a data source was created for possible outbreaks.

16s rRNA-based phylogenetic analyses of Elizabethkingia anophelis: Detection of Elizabethkingia anophelis, a rare infectious agent from blood and determination of antibiotic susceptibility in Turkey.

PURPOSE: Elizabethkingia anophelis was firstly isolated from the midgut of the Anopheles gambiae mosquito in 2011. After this year, it was isolated in some intensive care cases in Africa and Asia. This study, it was aimed to confirm the identification of E. anophelis in the blood of a pediatric patient. METHODS: After the suspicious bacteria were grown on blood agar, MALDI-TOF MS and 16s rRNA gene sequencing methods were used to identify and an antibiotic susceptibility test was carried out by Vitek 2 Compact system according to the EUCAST. Finally, a phylogenetic tree was created based on the 16s rRNA gene region. RESULTS: The isolate was identified as E. anophelis by both methods. It was found to be resistant to all beta-lactam antibiotics and also susceptible to ciprofloxacin and levofloxacin. According to the 16S rRNA-based phylogenetic tree, our isolate clustered within a branch containing other E. anophelis. CONCLUSION: These findings will guide clinicians in choosing which antibiotic to choose if they encounter this agent. Also, the clinicians should be vigilant against this agent, as it is a newly emerging infectious agent in Turkey.

Alternative screening method for analyzing the water samples through an electrical microfluidics chip with classical microbiological assay comparison of P. aeruginosa.

Pseudomonas aeruginosa is a pathogenic bacterium in fresh water supplies that creates a risk for public health. Microbiological analysis of drinking water samples is time consuming and requires qualified personnel. Here we offer a screening system for rapid analysis of spring water that has the potential to be turned into a point-of-need system by means of simple mechanism. The test, which takes 1 h to complete, electrically interrogates the particles through a microfluidic chip suspended in the water sample. We tested the platform using water samples with micro beads and water samples spiked with P. aeruginosa at various concentrations. The mono disperse micro beads were used to evaluate the performance of the system. The results were verified by the gold standard membrane filtration method, which yielded a positive test result only for the P. aeruginosa spiked samples. Detection of 0-11 k bacteria in 30 µL samples was successfully completed in 1 h and compared with a conventional microbiological method. The presented method is a good candidate for a rapid, on-site, screening test that can result in a significant reduction in cost and analysis time compared to microbiological analyses routinely used in practice.

An evaluation of false-positive rifampicin resistance on the Xpert MTB/RIF.

BACKGROUND: Mycobacterium tuberculosis (MTB) is one of the most significant causes of mortality and morbidity. Early diagnose is important especially in multiple drug resistant tuberculosis to avoid transmission. Traditional techniques requires at least one to three weeks for diagnosis of tuberculosis. Diagnostic delays with multiple drug resistant tuberculosis are associated with worse clinical outcomes and increased transmission The Xpert MTB/RIF assay is one of the new diagnostic device for the diagnosis of tuberculosis and rapid detection of rifampicin resistance. OBJECTIVE: We assessed the performance of Xpert MTB/RIF assay for detecting rifampicin resistance using phenotypic drug susceptibility tests as automated BD MGIT 960. METHODS: Total of 2136 specimens were included in the study. Xpert MTB/RIF testing was performed on samples, using version 4 cartridges, according to the manufacturer's recommendations. The MTBC culture and first-line phenotypic DST were performed in automated BD MGIT 960 (Becton & Dickinson, USA) according to the recommendations of the manufacturer. Agar proportion was used in the case of inconsistency for rifampicin resistance. FINDINGS: Thirty-four samples (19 respiratory and 15 nonrespiratory samples) were determined as positive for M. tuberculosis complex by Xpert MTB/RIF (Cepheid GeneXpert® System, USA). Xpert MTB/RIF assay detected 4/34 (11.7%) specimens as rifampicin resistant. One of the rifampicin resistant isolates was determined susceptible in MGIT 960 automated system. This isolate was also tested with agar proportion method and found susceptible to rifampicin. MAIN CONCLUSION: The Xpert MTB/RIF assay can be used as first-line assay for the detection of M. tuberculosis. However, microbiologists must be aware of the limitations of the assay.

An evaluation of false-positive rifampicin resistance on the Xpert MTB/RIF

BACKGROUND Mycobacterium tuberculosis (MTB) is one of the most significant causes of mortality and morbidity. Early diagnose is important especially in multiple drug resistant tuberculosis to avoid transmission. Traditional techniques requires at least one to three weeks for diagnosis of tuberculosis. Diagnostic delays with multiple drug resistant tuberculosis are associated with worse clinical outcomes and increased transmission The Xpert MTB/RIF assay is one of the new diagnostic device for the diagnosis of tuberculosis and rapid detection of rifampicin resistance. OBJECTIVE We assessed the performance of Xpert MTB/RIF assay for detecting rifampicin resistance using phenotypic drug susceptibility tests as automated BD MGIT 960. METHODS Total of 2136 specimens were included in the study. Xpert MTB/RIF testing was performed on samples, using version 4 cartridges, according to the manufacturer's recommendations. The MTBC culture and first-line phenotypic DST were performed in automated BD MGIT 960 (Becton & Dickinson, USA) according to the recommendations of the manufacturer. Agar proportion was used in the case of inconsistency for rifampicin resistance. FINDINGS Thirty-four samples (19 respiratory and 15 nonrespiratory samples) were determined as positive for M. tuberculosis complex by Xpert MTB/RIF (Cepheid GeneXpert® System, USA). Xpert MTB/RIF assay detected 4/34 (11.7%) specimens as rifampicin resistant. One of the rifampicin resistant isolates was determined susceptible in MGIT 960 automated system. This isolate was also tested with agar proportion method and found susceptible to rifampicin. MAIN CONCLUSION The Xpert MTB/RIF assay can be used as first-line assay for the detection of M. tuberculosis. However, microbiologists must be aware of the limitations of the assay.

Comparison of a real-time polymerase chain reaction-based system and Erlich-Ziehl-Neelsen method with culture in the identification of Mycobacterium tuberculosis.

BASCKGROUND/AIM: Mycobacterium tuberculosis is still a major health problem throughout the world, especially in developing countries. Disease control heavily depends on the establishment of early diagnosis. The aim of this study is to compare the efficacy of culture, GeneXpert MTB/RIF device, and Erlich-Ziehl-Neelsen direct microscopic method. MATERIALS AND METHODS: A total of 927 samples (243 respiratory and 684 nonrespiratory), which were sent to Ondokuz Mayis University Medical Faculty Tuberculosis Laboratory on suspicion of M. tuberculosis, were included in the study. RESULTS: When compared to standard culture, sensitivity, specificity, and positive and negative predictive values of the GeneXpert system for respiratory samples were 100%, 98.7%, 87%, and 100%, respectively; these values for nonrespiratory samples were 71%, 98.6%, 71%, and 98.6%, respectively. CONCLUSION: New, reliable, rapid, and easy-to-use methods that display high specificity and sensitivity are required for an effective struggle against tuberculosis. According to these results, we suggest that GeneXpert MTB/RIF is a rapid and reliable system, and when used in company with conventional tests, it would make significant contributions to the diagnosis of tuberculosis.

In Vivo Efficacy of Drugs against Toxoplasma gondii Combined with Immunomodulators.

The aim of this study is to evaluate the effects of pyrimethamine (PYR) and sulfadiazine (SDZ) combined with levamisole and echinacea on the survival of mice infected with Toxoplasma gondii. For this, we used 99 specific pathogen-free BALB/c mice. All the mice were infected intraperitoneally with 10(5) T. gondii tachyzoites and were divided into 11 groups, each including 9 mice. Except for the control group, oral treatment was initiated in all groups 24 h post infection and was continued for 10 days. The treatment regimen included dual combinations of PYR (dose, 6.25 and 12.5 mg/kg/day) and SDZ (dose, 100 and 200 mg/kg/day), triple combinations of PYR + SDZ, and levamisole (dose, 2.5 mg/kg/day) or echinacea (dose, 130 and 260 mg/kg/day) and echinacea alone (dose, 130 and 260 mg/kg/day). We observed that an effective dose of the combination of PYR + SDZ and levamisole resulted in a statistically significant increase in the survival rate from 33.3% to 88.9%. Similarly, half the dose of this combination resulted an increase in the survival rate from 0% to 44.4% (p < 0.05). Survival rate also increased in the groups treated with the combinations including echinacea; however, the difference did not reach statistical significance. The triple combination of PYR-SDZ-levamisole could be an alternative treatment option in case of infections caused by T. gondii.

Ceftaroline activity on certain respiratory tract and wound infection agents at the minimum inhibitory concentration level.

INTRODUCTION: The aim of this study was to investigate the effectiveness of ceftaroline against agents frequently isolated from respiratory tract and wound infections. METHODOLOGY: The study included a total of 250 strains isolated from various clinical specimens, among which were Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysagalactiae, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catharralis. The bacteria were identified using the matrix-assisted laser desorption/ionization time-of-flight method and conventional methods. The bacteria's antibiotic susceptibility was tested using appropriate broth microdilution. Mueller-Hinton broth with 4% lysed horse blood, Haemophilus test medium broth, and Mueller-Hinton broth were used. Ceftaroline fosamil results at the minimum inhibitory concentration (MIC) were evaluated using Clinical and Laboratory Standards Institute (CLSI) criteria. For quality assurance, E. coli ATCC 35218, S. aureus ATCC 29213, S. aureus ATCC 43300, S. pneumoniae ATCC 49619, H. influenzae ATCC 49766, H. influenzae ATCC 10211, and H. influenzae ATCC 49247 standard strains were used. RESULTS: According to CLSI criteria, resistance was not detected in any strains. Due to the absence of CLSI criteria for M. catharralis, the susceptibility state for this bacterium was not evaluated. The various strains' MIC50-MIC90 values were as follows: for S. pyogenes, 0.015-0.06; for S. agalactiae, 0.03-0.125; for S. dysagalactiae, 0.03-0.06; for S. pneumoniae, 0.06-0.125; for H. influenzae, 0.015-0.125; and for M. catharralis, 0.5-1. CONCLUSIONS: The results indicate that ceftaroline is quite effective against bacteria that are frequently isolated from respiratory tract and wound infections.

[Investigation of acid proteinase and phospholipase activity as virulence factors in clinical Aspergillus spp. isolates]. / Klinik Aspergillus spp. izolatlarinda virülans faktörü olarak asit proteinaz ve fosfolipaz aktivitelerinin arastirilmasi

Aspergillus spp. are widespread in nature and cause severe infections especially in immunocompromised patients. Aspergillus fumigatus complex is the most common species that causes infections in humans; however Aspergillus niger complex and Aspergillus flavus complex are the emerging agents that are isolated frequently from clinical specimens more recently. Besides the host factors such as immunosuppression, hematologic malignancy and corticosteroid use, fungal virulence factors such as elastase, acid protease and phospholipase enzymes are considered among the factors that affect the development of invasive aspergillosis. The aim of this study was to detect the acid proteinase and phospholipase enzyme activities in 30 A.fumigatus complex, nine A.flavus complex and four A.niger complex strains isolated from clinical specimens. Acid proteinase and phospholipase activities of the isolates were investigated by using bovine serum albumin agar (BSA), and egg yolk agar plates, respectively. Acid proteinase and phospholipase activity was detected in 76.7% (23/30) and 93.3% (28/30) of A.fumigatus complex isolates, respectively. None of the nine A.flavus complex isolates exhibited acid proteinase or phospholipase activity. Acid proteinase activity was not detected in any of the A.niger complex isolates (n= 4), however phospholipase activity was detected in one (25%) isolate. All of the acid proteinase positive A.fumigatus complex strains (n= 23) were also positive for phospholipase activity. In conclusion, further larger scale multicenter studies supported by clinical data, are needed to enlighten the roles of acid proteinase and phospholipase in the pathogenesis of infections due to Aspergillus spp.

[Isosporiasis in an elderly patient with chronic diseases: case report]. / Yasli Bir Hastada Kronik Hastaliklara Eslik Eden Isosporiyazis: Olgu Sunumu.

Isospora belli is a coccidian protozoon that can cause serious diarrhea especially in immunocompromised patients. The laboratory diagnosis depends primarily on the identification of oocysts in stool specimens by direct microscopic examination with iodine or special stains. This case is presented in order to draw attention to isosporiasis among the diarrheas that can be seen in elderly patients with several chronic diseases. A 81 year-old debilitated male, who had a history of hypertension, Alzheimer's disease, previous cerebrovascular accident and right hemiplegia, was admitted to our hospital complaining of malaise, anorexia, chills, abdominal pain, dysuria, cough, sputum and diarrhea of ten days duration. I. belli oocysts were detected by microscopic examination of the sample with iodine after concentration by formalin-ethyl acetate sedimentation. Then, modified acid-fast and trichrome stains were performed and I. belli oocysts were detected with both methods. Similar to this case, infections caused by I. belli can occur in elderly immunocompromised patients with several chronic diseases and inadequate nutrition and care. Consequently, in individuals with persistent diarrhea, examinations and tests should be carried out by taking their immune status into consideration and stool examinations should be done at frequent intervals using the concentrations methods and special stains.

Comparison of Culture, Real-Time DNA Amplification Assay and Ehrlich-Ziehl-Neelsen for Detection of Mycobacterium tuberculosis.

OBJECTIVE: Mycobacterium tuberculosis is still a substantial health problem universally. Although culture is the gold standard method, reliable, rapid and new methods are required for effective struggle with disease. We retrospectively compared the results of Ehrlich-Ziehl-Neelsen (EZN) stain and real-time DNA amplification assay (BD ProbeTec ET system) with culture. STUDY DESIGN: Retrospective study. MATERIAL AND METHODS: A total of 703 samples, 182 pulmonary and 521 extra pulmonary, collected from 630 patients between May 2008 and February 2011 were evaluated. Culture was considered the gold standard. RESULTS: For pulmonary specimens, sensitivity, specificity, positive predictive and negative predictive values of BD ProbeTec ET and EZN were calculated to be 100%, 98.8%, 87.5%, 100% and 71.4%, 98.8%, 83.3%, 97.6%, respectively. For extra pulmonary specimens, sensitivity, specificity, positive predictive and negative predictive values of BD ProbeTec ET and EZN were calculated to be 80%, 98.7%, 76.9%, 98.9% and 24%, 98.3%, 42.8%, 96.2%, respectively. CONCLUSION: According to these results, we suggest that the BD ProbeTec ET system is more reliable than EZN. In addition, the BD ProbeTec ET system produces faster results. Based upon these results, we consider that the BD ProbeTec ET system may be employed in the diagnosis of M. tuberculosis.

Synthesis, cytotoxicity and apoptosis of cyclotriphosphazene compounds as anti-cancer agents.

In the present study, a number of new dispirobino and dispiroansa spermine derivatives of cyclotriphosphazene (8-10, 13) were synthesized and characterized by elemental analysis, mass spectrometry, (1)H and (31)P NMR spectroscopy. At first, in vitro cytotoxic activity of cyclotriphosphazene compounds (1-14) against HT-29 (human colon adenocarcinoma), Hep2 (Human epidermoid larynx carcinoma), and Vero (African green monkey kidney) cell lines was investigated. Our study showed that most of these compounds stimulate apoptosis and they have cytotoxic effects for HT-29 and Hep2 cells. Additionally, these compounds (1-14) were investigated for their antibacterial activity against gram-positive (Staphylococcus aureus), gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and for their antifungal activity against Candida albicans, and were shown to be inactive.

Comparison of nosocomial candidemia of pediatric and adult cases in 2-years period at a Turkish university hospital.

OBJECTIVE: Although there are limited numerous reports of candidemia in adults, data on paediatrics are stil limeted. The aim of the present study was to compare the aetiology and risk factors of nosocomial candidemia among the paediatric and adults in our hospital. MATERIALS AND METHODS: This study includes the patients hospitalised and diagnosed as fungemia at Ondokuz Mayis University Hospital between June 30, 2007 and June 30, 2009 whose blood cultures sent to our microbiology laboratory. After fungal growth was observed in blood cultures, the yeast cells were inoculated onto Saboraud glucose agar. The colonies were identified by conventional yeast identification methods and ID 32C yeast identification system according to the manifacturer's instructions. RESULTS: During this period 51 paediatric and 69 adults were studied. The most common yeast form was Candida albicans (43.3%) followed by C. parapsilosis (25.0%) and C. tropicalis (17.5%). Although the non-albicans Candida species represent more than half (56.7%) of all candidemic cases C. albicans was the most common frequent etiologic agent. There was no statistically significant difference between patient age (paediatric and adult) and distribution of Candida species (p>0.05) Neoplasia (in adults) and prematurity (in paediatrics) were the main underlying diseases. Predisposing factors and mortality rates were not different among paediatrics and adults. CONCLUSION: We reinforce the necessity of continous epidomiologic surveillance to follow the dynamics of candidemia.

[Effect of linezolid in combination with isoniazid and rifampicin against multidrug resistant Mycobacterium tuberculosis clinical isolates]. / Cok ilaca dirençli Mycobacterium tuberculosis klinik izolatlarina karsi linezolidin izoniazid ve rifampisin ile kombine etkisi.

Tuberculosis continues to be a serious public health problem worldwide. Since multi-drug resistant strains of Mycobacterium tuberculosis constitutes a serious problem in tuberculosis control, new and more effective chemotherapeutic agents are required. This study was aimed to investigate the in vitro effect of linezolid alone and in combination with isoniazid and rifampicin against 10 multidrug resistant M. tuberculosis isolates by using the checkerboard method. Checkerboard testing was performed by the broth microdilution method, using Middlebrook 7H9 broth with 10% oleic acid-albumin-dextrose-catalase. Antibiotic combinations were tested at concentrations of 0.06-4 microg/ml for linezolid and 0.03-32 mg/ml for isoniazid and rifampicin. The results were evaluated according to the calculated fractional inhibitory concentration (FIC) index. All clinical isolates were found to be susceptible to linezolid; MICs of linezolid were 0.25 microg/ml for two strains and 0.5 microg/ml for the other strains. While rifampicin MIC values were >32 microg/ml for all the isolates, isoniazid MIC values were 4 microg/ml for two isolates, 8 microg/ml for six isolates, 16 microg/ml for one isolate and 32 microg/ml for one isolate. In this study, synergism was detected in only one strain between linezolid and isoniazid (FIC index: 0.265). Although synergy was observed between linezolid and isoniazid just for one strain, further larger scale in vitro and in vivo studies are necessary to evaluate the effect of different drug combinations against multidrug-resistant M. tuberculosis strains.

Comparative study for determination of Mycobacterium tuberculosis susceptibility to first- and second-line antituberculosis drugs by the Etest using 7H11, blood, and chocolate agar.

We investigated the performance of blood and chocolate agar as alternatives to Middlebrook 7H11 agar for testing the susceptibility of Mycobacterium tuberculosis to first-and second-line drugs by the Etest method. A total of 39 strains of M. tuberculosis including 22 multidrug-resistant M. tuberculosis strains and 17 susceptible strains were tested. In conclusion, our results showed that chocolate agar gave insufficient growth, needing up to 21 days of incubation, while results on blood agar were comparable to those on Middlebrook 7H11 agar and can be further explored as an alternative for Etest-based susceptibility testing of M. tuberculosis.

[Susceptibility testing of Mycobacterium tuberculosis isolates to primary antituberculous drugs on chocolate agar: a preliminary study]. / Mycobacterium tuberculosis izolatlarinin primer antitüberküloz ilaçlara duyarliliklarinin çikolatali agarda saptanmasi: Bir ön çalisma.

The aim of this study was to evaluate the use of chocolate agar as an alternative medium instead of Middlebrook 7H10 agar, for the susceptibility testing of Mycobacterium tuberculosis strains against isoniazid (INH), rifampicin (RIF), streptomycin (STR) and ethambutol (ETM). The susceptibility results obtained by chocolate agar were compared with the results of BACTEC 460 TB (Becton Dickinson, Sparks, MD, USA) system which was accepted as the reference method. A total of 25 M. tuberculosis clinical isolates were included to the study and susceptibility testing was performed on malachite green added-chocolate agar with some modifications of proportion method recommended by NCCLS. In our study when comparing the results obtained by chocolate agar with the results of BACTEC 460 TB system, the concordance rates for INH, STR, RIF and ETM were found as 88%, 88%, 84% and 72%, respectively. The specificity, sensitivity, positive and negative predictive values of susceptibility testing on chocolate agar have been detected as 82.3%, 100%, 72.7% and 100% for INH; 78.5%, 100%, 78.5% and 100% for RIF; 83.3%, 84.2%, 94.1% and 62.5% for STR; 25%, 94.1%, 72.7% and 66.6% for ETM, respectively. The results of the susceptibility testing performed on chocolate agar were obtained on the 21st day of incubation for all isolates. In conclusion, the data from our study suggested that chocolate agar can be used as an alternative medium for the susceptibility testing of M. tuberculosis, however, further studies with more isolates are needed for the standardisation of the method.

Two new colorimetric methods for early detection of vancomycin and oxacillin resistance in Staphylococcus aureus.

We developed two colorimetric methods for the detection of vancomycin- and oxacillin-resistant Staphylococcus aureus in

[Phospholipase activity of Candida species isolated from different clinical samples]. / Degisik klinik orneklerden izole edilen Candida türlerinde fosfolipaz aktivitesinin arastirilmasi.

In this study, the phospholipase activity that was suggested to be important in the pathogenesis of Candida infections, has been investigated. A total of 109 Candida strains (80 Candida albicans, 10 C. tropicalis, 6 C. glabrata, 6 C. guilliermondii, 4 C. parapsilosis, 2 C. krusei, 1 C. kefyr) which were isolated from various clinical specimens (blood, cerebrospinal fluid, parasynthesis specimens, catheter samples, bronchoalveolar lavage fluid, tracheal aspirate, liver abscess) have been included in the study. Phospholipase activities were evaluated by modified plate method. Phospholipase activity (Pz) was determined as the ratio of colony diameter to the diameter of precipitation zone with the colony. While 61.3% (49/80) of C. albicans strains were found to be positive for phospholipase activity, none of the non-albicans Candida isolates exhibited phospholipase activity. The mean Pz coefficient value of phospholipase secreting isolates was calculated as 0.805 +/- 0.08. There was no statistically significant difference between the phospholipase activity of the isolates according to their isolation sites (chi2 = 5.5; p = 0.137).