Diagnostic performance and longitudinal analysis of fungal biomarkers in COVID-19 associated pulmonary aspergillosis.

Objectives: Galactomannan lateral flow assay (GM-LFA) is a reliable test for COVID-19 associated pulmonary aspergillosis (CAPA) diagnosis. We aimed to assess the diagnostic performance of GM-LFA with different case definitions, the association between the longitudinal measurements of serum GM-ELISA, GM-LFA, and the risk of death. Methods: Serum and nondirected bronchial lavage (NBL) samples were periodically collected. The sensitivity and specificity analysis for GM-LFA was done in different time periods. Longitudinal analysis was done with the joint model framework. Results: A total of 207 patients were evaluated. On the day of CAPA diagnosis, serum GM-LFA had a sensitivity of 42 % (95 % CI: 23-63) and specificity of 82 % (95 % CI: 78-84), while NBL GM-LFA had a sensitivity of 73 % (95 % CI: 45-92), specificity of 85 % (95 % CI: 76-91) for CAPA. Sensitivity decreased through the following days in both samples. Univariate joint model analysis showed that increasing GM-LFA and GM-ELISA levels were associated with increased mortality, and that effect remained same with serum GM-ELISA in multivariate joint model analysis. Conclusion: GM-LFA, particularly in NBL samples, seems to be a reliable method for CAPA diagnosis. For detecting patients with higher risk of mortality, longitudinal measurement of serum GM-ELISA can be useful.

Do the drug doses of conventional synthetic DMARDs used for the treatment of biologic/targeted-synthetic DMARDs naive rheumatoid arthritis patients affect QuantiFERON-TB Gold Plus test results?

We aimed to obtain the effects of immunosuppressive doses on the QuantiFERON-TB Gold Plus (QFT-Plus) test results in Rheumatoid Arthritis (RA) patients. Besides this, the impact of the TB2 tube in QFT-Plus test was also investigated. This study included RA patients registered to HURBIO and were screened via QFT-Plus test for latent tuberculosis between January 2018 and March 2021, before the initiation of treatment of biologic/targeted-synthetic disease modifying anti-rheumatismal drugs (b/ts-DMARDs). Patients using methotrexate ≥ 10 mg or leflunomide (any dose) or steroids (≥ 7.5 mg prednisolone) at the time of QFT-Plus test were classified as the "high dose" group and the rest of the patients constituted the "low dose" group. The study included 534 RA patients; 353 [66.1%] in the high-dose group and 181 [33.9%] in the low-dose group. While QFT-Plus test was positive in 10.5% (37/353) patients in the high-dose group, it was positive in 20.4% (37/181) patients in the low-dose group (p < 0.001). The percentage of QFT-Plus indeterminate results were similar (around 2%) in both groups. The contribution of the TB2 tube to QFT-Plus test positivity was 6.89%. During a median (inter-quartile range) follow-up period of 23 (7-38) months under treatment of b/ts-DMARDs, latent TB reactivation was not observed. Primer active tuberculosis disease developed in two patients. Positive test results of Interferon-Gamma Release Assays (IGRAs) could decrease as immunosuppressive treatment doses increase in patients with RA and addition of the TB2 tube could increase test sensitivity.

A case-control study of the effects of Aspergillus clinical phenotypes on pulmonary functions in patients with cystic fibrosis.

INTRODUCTION: There are no precise data about the effect of Aspergillus infection on lung function other than allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis (pwCF). Here, we aimed to determine clinical phenotypes caused by Aspergillus spp. using laboratory and immunologic parameters and to compare Aspergillus phenotypes in terms of pulmonary function tests (PFT) prospectively. METHODS: Twenty-three pwCF who had Aspergillus isolation from respiratory cultures in the last year (case group) and 20 pwCF without Aspergillus isolation in sputum (control group) were included. Aspergillus immunoglobulin (Ig)-G, Aspergillus IgE, Aspergillus polymerase chain reaction (PCR), galactomannan, total IgE from blood samples, and Aspergillus PCR and galactomannan from sputum, and skin prick test reactivity to Aspergillus antigen were used to distinguish different Aspergillus phenotypes. Pulmonary functions and frequency of pulmonary exacerbations were evaluated during a 1-year follow-up. RESULTS: Of 23 pwCF, 11 (47.8%) had Aspergillus colonization, nine (39.1%) had Aspergillus bronchitis, and three (13%) had ABPA. Aspergillus infection was not associated with worse z-scores of forced expiratory volume in the first second (FEV1) (p = 0.612), forced vital capacity  (p = 0.939), and the median FEV 1% decline (0.0%/year vs. -4.7%/year, p = 0.626). The frequency of pulmonary exacerbations in the Aspergillus infected and noninfected groups was similar. CONCLUSION: Although Aspergillus spp. Isolation in pwCF was not associated with decreased lung function, a further decline was seen in the ABPA subgroup, and frequent pulmonary exacerbations during the 1-year follow-up.

The correlation of serum sPD-1 and sPD-L1 levels with clinical, pathological characteristics and lymph node metastasis in nonsmall cell lung cancer patients.

BACKGROUND: Significant advances have been achieved in immunotherapy for the treatment of lung cancer. It is known that tumor cells and cells in the tumor microenvironment express high amounts of programmed cell death ligand 1 (PD-L1). These PD-L1s interact with programmed cell death protein 1 (PD-1), causing immunosuppression. The aim of our study is to examine the correlation between the serum sPD-1 and sPD-L1 levels and clinicopathological characteristics in patients with nonsmall cell lung cancer. We also compared our results with the healthy population (control group). METHODS: Thirthy-seven nonsmall cell lung cancer (NSCLC) patients who were operated in our clinic were included in our study. The control group included fifteen healthy patients. The sPD-1 and sPD-L1 levels were measured in serum samples by using the ELISA method. RESULTS: The preoperative sPD-1 and sPD-L1 levels were significantly higher in the study group compared to the control group (44.12 ± 22.25 pg/mL vs. 18.54 ± 6.56 pg/mL; p = 0.001 and 26.15 ± 18.03 pg/mL vs. 10.29 ± 3.08 pg/mL; p = 0.001, respectively). There was a statistically significant decline in serum sPD-1 and sPD-L1 levels at the preoperative and postoperative 1st, 7th, and 30th days following surgical resection (44.12 ± 22.25 pg/mL, 37.86 ± 18.02 pg/mL, 36.33 ± 18.36 pg/mL, 34.14 ± 13.71 pg/mL; p = 0.007 and 26.15 ± 18.03 pg/mL, 20.60 ± 15.50 pg/mL, 18.31 ± 14.04 pg/mL, 13.64 ± 10.60 pg/mL; p = 0.001, respectively).There was a positive correlation between the preoperative and postoperative 30th day serum sPD-1 levels and the tumor size (p = 0.031, r = 0.352; p = 0.024, r = 0.371; respectively). We also found a positive correlation between the preoperative and postoperative 30th day serum sPD-L1 levels and pleural invasion (p = 0.001, p = 0.001; respectively), and the N category (p = 0.015, p = 0.013; respectively). DISCUSSION: We think that sPD-1 and sPD-L1 levels may be used as a potential biomarker for lung cancer screening, prediction of the stage, and besides to detect recurrences and/or metastases following resection in NSCLC following validation with multicenter and larger-scale prospective trials.

A screening study for COVID-19-associated pulmonary aspergillosis in critically ill patients during the third wave of the pandemic.

BACKGROUND: COVID-19-associated pulmonary aspergillosis (CAPA) has been reported as an important cause of mortality in critically ill patients with an incidence rate ranging from 5% to 35% during the first and second pandemic waves. OBJECTIVES: We aimed to evaluate the incidence, risk factors for CAPA by a screening protocol and outcome in the critically ill patients during the third wave of the pandemic. PATIENTS/METHODS: This prospective cohort study was conducted in two intensive care units (ICU) designated for patients with COVID-19 in a tertiary care university hospital between 18 November 2020 and 24 April 2021. SARS-CoV-2 PCR-positive adult patients admitted to the ICU with respiratory failure were included in the study. Serum and respiratory samples were collected periodically from ICU admission up to CAPA diagnosis, patient discharge or death. ECMM/ISHAM consensus criteria were used to diagnose and classify CAPA cases. RESULTS: A total of 302 patients were admitted to the two ICUs during the study period, and 213 were included in the study. CAPA was diagnosed in 43 (20.1%) patients (12.2% probable, 7.9% possible). In regression analysis, male sex, higher SOFA scores at ICU admission, invasive mechanical ventilation and longer ICU stay were significantly associated with CAPA development. Overall ICU mortality rate was higher significantly in CAPA group compared to those with no CAPA (67.4% vs 29.4%, p < .001). CONCLUSIONS: One fifth of critically ill patients in COVID-19 ICUs developed CAPA, and this was associated with a high mortality.

Correlation of Treponemal Chemiluminescent Microparticle Immunoassay Screening Test Signal Strength Values With Reactivity of Confirmatory Testing.

BACKGROUND: Automated chemiluminescent microparticle immunoassays (CMIAs) are the most common first step at high-volume laboratories for syphilis screening. If the initial screening test is reactive, 1 more treponemal test is required, resulting in increased cost. In this multicenter study, we aimed to determine the correlation between the CMIA signal-to-cutoff ratio (S/Co) and the confirmatory tests to reduce unnecessary confirmatory testing. METHODS: Eight hospitals from 5 provinces participated in this study. All laboratories used Architect Syphilis TP CMIA (Abbott Diagnostics, Abbott Park, IL) for initial screening. Treponema pallidum hemagglutination (TPHA), rapid plasma reagin (RPR), and fluorescent treponemal antibody absorption (FTA-ABS) were used as confirmatory tests according to the reverse or European Centre for Disease Prevention and Control algorithms. A receiver operating characteristic analysis was used to determine the optimal S/Co ratio to predict the confirmation results. RESULTS: We evaluated 129,346 serum samples screened by CMIA between January 2018 and December 2020. A total of 2468 samples were reactive; 2247 (91%) of them were confirmed to be positive and 221 (9%) were negative. Of the 2468 reactive specimens, 1747 (70.8%) had an S/Co ratio ≥10.4. When the S/Co ratios were ≥7.2 and ≥10.4, the specificity values were determined to be 95% and 100%, respectively. In a subgroup of 75 CMIA-positive patients, FTA-ABS was performed and 62 were positive. Among these FTA-ABS-positive patients, 24 had an S/Co ratio <10.4, and negative TPHA and RPR. CONCLUSIONS: We propose a potentially cost-effective reverse screening algorithm with a treponemal CMIA S/Co ratio ≥10.4, obviating the need for secondary treponemal testing in about 71% of the screening-reactive samples. This would substantially reduce the confirmatory testing volume and laboratory expenses. However, in high-risk group patients with CMIA positive results, S/Co ratio <10.4, and negative TPHA and RPR, FTA-ABS may be used for confirmation.

The frequency and related factors of non-tuberculosis mycobacteria infections among patients with cystic fibrosis.

BACKGROUND: Non-tuberculous mycobacteria (NTM) can cause chronic lung infection particularly in patients who have structural lung disease such as cystic fibrosis (CF). We evaluated the incidence and management of NTM infections in patients with CF in our center. METHODS: A retrospective cohort study was carried out on CF patients having at least one positive NTM isolate between 2012 and 2020. RESULTS: Ten patients (2.1%) had at least one positive NTM culture from respiratory samples. All of them were vaccinated with Bacille Calmette-Guérin (BCG) vaccine, which is in the national vaccination program in our country. Eight patients had the Mycobacterium abscessus complex, one had Mycobacterium avium, and one had Mycobacterium szulgai growth in their respiratory samples. Three patients had transient NTM infection, two had persistent, and five had active NTM infection (NTM pulmonary disease). Patients with NTM pulmonary disease received antibiogram-directed antimycobacterial therapy. In patients with NTM pulmonary disease, the median ppFEV1 and BMI decreased by 17% and 1%, respectively, at the time of the first NTM isolation when compared with the values one year before the first NTM isolation. Culture conversion was not seen in any patient infected with Mycobacteriunm abscessus complex. CONCLUSIONS: The NTM infection incidence is lower in our country than in those countries where the BCG vaccine is not routinely applied. The BCG vaccine may be a protective factor for NTM infection. Further studies are needed about the prevalence of NTM infections, facilitating and protective factors, and appropriate management of NTM infections in patients with CF.

[Evaluation of Anyplex MTB/NTM Test for The Detection of Mycobacterium tuberculosis in Clinical Specimens]. / Klinik Örneklerden Mycobacterium tuberculosis Saptanmasinda Anyplex MTB/NTM Testinin Degerlendirilmesi.

One of the most important steps for the control of tuberculosis is rapid and accurate detection of Mycobacterium tuberculosis in clinical samples. The early and accurate diagnosis of tuberculosis allows the initiation of the effective treatment regimen as early as possible. However the early diagnosis of tuberculosis can be achieved by the integration of molecular methods into the diagnostic algorithm of tuberculosis together with the gold standard culture methods. For this reason, molecular methods have become valuable diagnostic tools in routine diagnostic laboratories in recent years. The aim of this study was to determine the diagnostic efficacy of Anyplex MTB/NTM test (Seegene, South Korea) used for the molecular diagnosis of tuberculosis in routine molecular diagnostic laboratories. In addition to this aim, a preliminary evaluation of in-house polymerase chain reaction (PCR) primers that was designed to produce a kit as an alternative against imported commercial kits was performed. Ten thousand six hundred fifthy two clinical specimens that were collected from suspected tuberculosis cases in three years were included in the study. All samples were tested by microscopic examination after staining, culture and real-time PCR (Rt-PCR) methods. The smears were examined by microscope after staining with Kinyoun method for the existence of acid resistant bacilli. For culture, following the N-acetyl-L-sistein-sodium hydroxide homogenization and decontamination procedure, the samples were inoculated into the MGIT (Mycobacteria Growth Indicator Tube) tubes (Becton Dickinson, USA). Rt-PCR method was performed by using Anyplex MTB/NTM test. In the first stage of the study, the performance of the Anyplex MTB/NTM test was compared with the gold standard culture method. M.tuberculosis was isolated in 178 specimens out of 10.652 (1.7%). After the comparison with the gold standard culture method, the sensitivity and specificity of Anyplex MTB/NTM test was found to be 84% and 99% respectively in pulmonary samples, and 74% and 99% respectively in extrapulmonary samples. In the second stage of the study, PCR method with laboratory designed primers was applied to 100 culture positive samples. The PCR results of 98 samples were found to be in agreement with the culture, while M.tuberculosis DNA was not detected in two samples. As a result of the study it was concluded that Anyplex MTB/NTM test is a rapid, practical and reliable method that can be used in routine tuberculosis diagnosis. The high agreement between PCR method using the laboratory-designed primers and the PCR method used in routine practice will lighten the way for the development of national tuberculosis molecular diagnostic kits with a relevant cost. In this way, it will be possible to perform rapid diagnosis in a more cost-effective manner in routine diagnosis laboratories.

[Comparison of microdilution and disk diffusion methods for the detection of fluconazole and voriconazole susceptibility against clinical Candida glabrata isolates and determination of changing susceptibility with new CLSI breakpoints]. / Klinik Candida glabrata izolatlarinda flukonazol ve vorikonazol duyarliliginin saptanmasinda mikrodilüsyon ve disk difüzyon yöntemlerinin karsilastirilmasi ve yeni CLSI direnç sinir degerleri ile duyarlilik sonuçlarindaki degisimin belirlenmesi.

Candida albicans is the most frequently isolated species as the causative agent of Candida infections. However, in recent years, the isolation rate of non-albicans Candida species have increased. In many centers, Candida glabrata is one of the commonly isolated non-albicans species of C.glabrata infections which are difficult-to-treat due to decreased susceptibility to fluconazole and cross-resistance to other azoles. The aims of this study were to determine the in vitro susceptibility profiles of clinical C.glabrata isolates against fluconazole and voriconazole by microdilution and disk diffusion methods and to evaluate the results with both the previous (CLSI) and current species-specific CLSI (Clinical and Laboratory Standards Institute) clinical breakpoints. A total of 70 C.glabrata strains isolated from clinical samples were included in the study. The identification of the isolates was performed by morphologic examination on cornmeal Tween 80 agar and assimilation profiles obtained by using ID32C (BioMérieux, France). Broth microdilution and disk diffusion methods were performed according to CLSI M27-A3 and CLSI M44-A2 documents, respectively. The results were evaluated according to CLSI M27-A3 and M44-A2 documents and new vs. species-specific CLSI breakpoints. By using both previous and new CLSI breakpoints, broth microdilution test results showed that voriconazole has greater in vitro activity than fluconazole against C.glabrata isolates. For the two drugs tested, very major error was not observed with disk diffusion method when microdilution method was considered as the reference method. Since "susceptible" category no more exists for fluconazole vs. C.glabrata, the isolates that were interpreted as susceptible by previous breakpoints were evaluated as susceptible-dose dependent by current CLSI breakpoints. Since species-specific breakpoints remain yet undetermined for voriconazole, comparative analysis was not possible for this agent. The results obtained at 24 hours by disk diffusion method were evaluated by using both previous and current CLSI breakpoints and the agreement rates for fluconazole and voriconazole were 80% and 92.8% with previous CLSI breakpoint, 87.1% and 94.2% with new breakpoints, respectively. The high agreement rates between the two methods obtained by the new breakpoints in particular suggest that disk diffusion appears as a reliable alternative method in general for in vitro susceptibility testing of fluconazole and voriconazole against C.glabrata isolates.

[Multicenter evaluation of the indirect nitrate reductase assay for the rapid detection of multidrug-resistant tuberculosis]. / Çok ilaca dirençli tüberkülozun hizli tespiti için dolayli nitrat redüktaz testinin çok merkezli degerlendirilmesi.

Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to at least isoniazid (INH) and rifampicin (RIF), and it complicates the implementation of tuberculosis control programmes. The rapid detection of MDR-TB is crucial to reduce the transmission of disease. The nitrate reductase assay (NRA) is one of the colorimetric susceptibility test methods for rapid detection of MDR-TB and based on the ability of reduction of nitrate to nitrite by Mycobacterium tuberculosis. The aim of this study was to evaluate the performance of the NRA for the rapid detection of MDR-TB. A total of 237 M.tuberculosis complex (MTC) isolates that were identified by the same method (BD MGIT(TM) TBc Identification Test, USA) from nine different medical centers in Turkey were included in the study. The susceptibility results of the isolates against INH and RIF obtained by reference test (Bactec MGIT(TM) 960, BD, USA) were then compared with NRA. In order to ensure consistency between centers, Löwenstein-Jensen (LJ) medium with antibiotics and without antibiotics (growth control) and Griess reagent solution were prepared in a single center (Ondokuz Mayis University School of Medicine, Medical Microbiology Department) and sent to all participant centers with the standardized test procedure. After the inoculation of bacteria into the test tubes, the tubes were incubated at 37°C, and after seven days of incubation, 500 µl Griess reagent was added to the LJ medium without antibiotics. If a color change was observed, an equal volume of Griess reagent was added to test LJ media with antibiotics. When a color change was observed in LJ media with antibiotics, it was considered that the isolate was resistant to tested antibiotics. Among 237 MTC isolates, 16 were resistant only to INH and nine were resistant only to RIF; 93 isolates (39.2%) were resistant (MDR) and 119 isolates (50.2%) were susceptible to both of the drugs determined with the reference susceptibility test. In the study, five INH-resistant isolates determined with reference method were found susceptible with NRT and eight INH-susceptible isolates determined with reference method were found resistant with NRT. In contrast, one RIF-resistant isolate determined with reference method was found susceptible with NRT and three RIF-susceptible determined isolates were found resistant with NRT. Accordingly, the concordance rate between the reference method and NRA were estimated as 94.5% for INH and 98.3% for RIF. The sensitivity, specificity, positive and negative predictive values of NRA were detected as 95.4%, 93.7%, 92.8% and 96% for INH, and 99%, 97.8%, 97.1% and 99.2% for RIF, respectively. The results of the 111 isolates were obtained on the seventh day, while the rest of the results were obtained between 10-14 days. In conclusion, the data of this multicenter study showed that NRA is a reliable, relatively inexpensive and practical method to perform for the rapid detection of MDR-TB.

Pulmonary Mycobacterium abscessus Infection in a Patient with Triple A Syndrome.

Gastroesophageal disorders such as achalasia can be associated with pulmonary disorders because of non-tuberculous mycobacteria, frequently masquerading as aspiration pneumonia. The optimal therapeutic regimen and duration of treatment for non-tuberculous mycobacteria lung disease is not well established. Here, we present an 11 year old male patient with Mycobacterium abscessus pulmonary disease and underlying triple A syndrome, who was successfully treated with 2 months of imipenem, amikacin, clarithromycin and continued for long-term antibiotic treatment.

Detection of cagA and vacA genotypes of Helicobacter pylori isolates from a university hospital in Ankara region, Turkey.

AIM: The cagA and vacA profiles and their association with clinical findings show a distinct geographical distribution. In the present study, we aimed to determine the cagA status and vacA allelic subtypes in strains isolated from a university hospital in Ankara and to evaluate their associations with histopathological and endoscopic findings. MATERIALS AND METHODS: A total of 120 H. pylori strains from stock cultures positive for the ureA gene were randomly included in the present study. Of these strains, cagA and vacA allelic subtypes (s1a, s1b, s2, m1, m2) were examined by polymerase chain reaction. RESULTS: Of the 120 strains, 64 (53.3%) were cagA-positive. However, no significant relationship was found between clinical outcomes and cagA positivity. There were 38 (33.6%) strains that had vacA m1 and 74 (65.5%) that had vacA m2 region. Overall, 75 (70.1%) samples were classified as vacA sla, 3 (2.8%) as vacA slb, and 29 (27.1%) as vacA s2. There was no significant relationship between vacA genotypes and endoscopic findings. The predominant vacA genotypes were slam2 (35.6%) and slam1 (33.6%), with almost the same rates. Furthermore, cagA positivity was found to be significantly related with the vacA slam1 genotype. CONCLUSION: The cagA and vacA profiles of our study population are consistent with the Middle Eastern profile.

[The results of Hacettepe University Faculty of Medicine Parasitology Laboratory in 2003-2012: evaluation of 10 years]. / Hacettepe Üniversitesi Tip Fakültesi Parazitoloji Laboratuvari 2003-2012 Yillari Sonuçlari: 10 Yillik Degerlendirme.

OBJECTIVE: Parasitic diseases are common throughout the world. Evaluation of regional epidemiological data is needed to determine protective measures and treatment strategies. METHODS: This study evaluates the parasites detected in Hacettepe University Faculty of Medicine Parasitology Laboratory. RESULTS: Of the 87,100 clinical samples evaluated in the study, 85,707 (98.4%) were from stool samples. Parasites were shown in 3,681 (4.2%) of the samples from 2,906 patients. The most common parasites were Giardia intestinalis (40%), Blastocystis spp. (22%), Entamoeba coli (12%), Dientamoeba fragilis (9%), Enterobius vermicularis (5%), Echinococcus spp. (4%) and Taenia spp. (3%) respectively. When distribution among years was evaluated, G. intestinalis, the most common parasite, had a tendency to decrease after 2004 whereas cases with Blastocystis spp. showed a clear increase in 2011 and 2012. The downward trend in parasite-positive cases also stopped in the last two years, in parallel to the increase of Blastocystis spp. During the study, Leishmania spp. and Plasmodium spp. were detected in four patients each. CONCLUSION: This study evaluated the results of a laboratory that scans a large number of patients in our region. Data obtained from different regions will allow to direct strategies to diagnose, treat and implement preventive measures against parasitic diseases in our country.

[Isolation of Scedosporium apiospermum (teleomorph: Pseudallescheria apiosperma) from an acute myeloid leukemia patient]. / Bir akut miyeloid lösemi hastasindan Scedosporium apiospermum (teleomorf: Pseudallescheria apiosperma) izolasyonu.

Scedosporium apiospermum is an emerging opportunistic pathogen that may lead to life-threatening infections especially in immunosuppressive individuals. In this report, S.apiospermum infection in a 62 year old male patient with acute myeloid leukemia was presented. During remission-induction chemotherapy, piperacillin-tazobactam therapy was started for febrile neutropenia. Since fever had continued, treatment was switched to imipenem and also amphotericin B deoxycholate was added to the treatment protocol. Because of allergic reaction to amphotericin B, caspofungin was started at the fifth day of neutropenic fever. Following imaging studies with high resolution computerized thorasic tomography, antifungal therapy was changed to voriconazole due to findings suggestive of invasive aspergillosis. Since galactomannan antigen was found negative at the first day of voriconazole therapy, bronchoalveolar lavage material from apical segment of the left lower lobe was cultured onto various microbiologic media. S.apiospermum (Teleomorph: Pseudallescheria apiosperma) was isolated on the fourth day of cultivation. According to CLSI M38-A2 microdilution procedure, minimum inhibitory concentrations (MIC) of voriconazole, caspofungin, amphotericin B and posaconazole were found as 0.06, 2, 8 and 4 µg/ml, respectively. Since neutropenia was resolved, the patient was discharged with continued voriconazole therapy. It was concluded that antifungal susceptibility tests should be performed for Scedosporium species and the results should be compared to the clinical response. The determination of MIC breakpoints may provide useful information for the recommendation and use of optimal choices for the treatment of Scedosporium infections.

[Evaluation of Tetrazolium Violet and Resazurin Assays for Ciprofloxacin Susceptibility Testing of Resistant Mycobacterium tuberculosis Isolates]. / Dirençli Mycobacterium tuberculosis Izolatlarinda Siprofloksasin Direncinin Saptanmasinda Tetrazolyum Moru ve Resazurin Testlerinin Etkinliginin Degerlendirilmesi.

Tuberculosis, caused by Mycobacterium tuberculosis, is still a serious public health concern. Antimycobacterial drug resistance which is in an increasing trend worldwide aids to the importance of tuberculosis problem. Fluoroquinolones which exhibit in vitro and in vivo anti-mycobacterial activity, are being recommended by World Health Organization as alternative drugs particularly for the treatment of multidrug resistant tuberculosis. Rapid detection of antimycobacterial resistance is of great importance for the effective treatment of patients with tuberculosis. In this study, we evaluated the efficiency of tetrazolium violet (TV) and resazurin (RES) assays in terms of rapid detection of bacterial growth and ciprofloxacin resistance in M.tuberculosis clinical isolates. Thirty M.tuberculosis isolates which were resistant to at least one of the first-line anti-tuberculosis drugs were tested using TV and RES assays in addition to gold standard agar proportion test. Standard strain M.tuberculosis H37Ra was also included in each run. The tests were performed in four sets as TV and RES were added on day 5, 7, 10 and 12. For the TV assay, any change in colour from yellow to dark purple was recorded as bacterial growth. For the RES assay, any change in colour from blue to pink was recorded as bacterial growth. The optimal incubation period for detection of growth and resistance was 7 days for 25 of 30 bacteria. However, results for five isolates with low inoculum rates were detected on 10th and 12th days. Any change in colour in drug containing media was recorded as resistance to ciprofloxacin. All the susceptibility results were consistent with those obtained from agar proportion method. As indicated by our results, TV and RES assays are rapid and simple tests which could be used for detection of bacterial growth and ciprofloxacin resistance in M.tuberculosis clinical isolates. Widespread use of such colorimetric tests will help to minimize the need of sophisticated expensive susceptibilty test systems particularly in low income countries.

The efficacy of silver-embedded polypropylene-grafted polyethylene glycol-coated ventricular catheters on prevention of shunt catheter infection in rats.

PURPOSE: Catheter-related infection is a major complication of ventriculoperitoneal shunt in children. The aim of this study is to determine inflammatory response and the efficacy of polypropylene-grafted polyethylene glycol (PP-g-PEG) copolymer and silver nanoparticle-embedded PP-g-PEG (Ag-PP-g-PEG) polymer-coated ventricular catheters on the prevention of catheter-related infections on a new experimental model of ventriculoperitoneal shunt in rats. METHODS: Thirty six Wistar albino rats were divided into six groups: group 1, unprocessed sterile silicone catheter-embedded group; group 2, sterile PP-g-PEG-coated catheter group; group 3, sterile Ag-PP-g-PEG-coated catheter group; group 4, infected unprocessed catheter group; group 5, infected PP-g-PEG-coated catheter group; and group 6, infected Ag-PP-g-PEG-coated catheter group, respectively. In all groups, 1-cm piece of designated catheters were placed into the cisterna magna. In groups 4, 5, and 6, all rats were infected with 0.2 mL of 10 × 10(6) colony forming units (CFU)/mL Staphylococcus epidermidis colonies before the catheters were placed. Thirty days after implantation, bacterial colonization in cerebrospinal fluid and on catheter pieces with inflammatory reaction in the brain parenchyma was analyzed quantitatively. RESULTS: Sterile and infected Ag-PP-g-PEG-covered groups revealed significantly lower bacteria colony count on the catheter surface (ANOVA, 0 ± 0, p < 0.001; 1.08 ± 0.18, p < 0.05, respectively). There was moderate inflammatory response in the parenchyma in group 4, but in groups 5 and 6, it was similar to that of the sterile group (ANOVA, 16.33 ± 3.02, p < 0.001; 4.00 ± 0.68, p < 0.001, respectively). CONCLUSIONS: The PP-g-PEG, especially Ag-PP-g-PEG polymer-coated ventricular catheters are more effective in preventing the catheter-related infection and created the least inflammatory reaction in the periventricular parenchyma.

Critical appraisal of air pouch infection model in rats.

The aim of this study was to assess the efficacy and pharmacokinetic profiles of gentamicin, vancomycin, and levofloxacin in a rat air pouch model, in which Staphylococcus aureus (ATCC 25293) was used as the test organism. Antibiotic treatments (i.p.) were started 1 hour after bacterial inoculation and continued for 5 days. Bacterial counts and antibiotic concentrations were determined in pouch exudates that were obtained on the 5th day of antibiotic treatment. The following observations were made: 1) The concentrations of gentamicin or vancomycin in the exudate were found to be below the detection limit. 2) Levofloxacin and ciprofloxacin exhibited a dose-dependent effect on bacterial counts in the exudate. 3) The antibacterial efficacy of levofloxacin was found to be enhanced when the total daily dose of 10 mg was divided into smaller parts. The present study also showed that the air pouch infection model was a valuable tool to assess the pharmacokinetic and pharmacodynamic properties of antibiotics.

Distribution of spoligotyping defined genotypic lineages among drug-resistant Mycobacterium tuberculosis complex clinical isolates in Ankara, Turkey.

BACKGROUND: Investigation of genetic heterogeneity and spoligotype-defined lineages of drug-resistant Mycobacterium tuberculosis clinical isolates collected during a three-year period in two university hospitals and National Tuberculosis Reference and Research Laboratory in Ankara, Turkey. METHODS AND FINDINGS: A total of 95 drug-resistant M. tuberculosis isolates collected from three different centers were included in this study. Susceptibility testing of the isolates to four major antituberculous drugs was performed using proportion method on Löwenstein-Jensen medium and BACTEC 460-TB system. All clinical isolates were typed by using spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) methods. Seventy-three of the 95 (76.8%) drug resistant M. tuberculosis isolates were isoniazid-resistant, 45 (47.4%) were rifampicin-resistant, 32 (33.7%) were streptomycin-resistant and 31 (32.6%) were ethambutol-resistant. The proportion of multidrug-resistant isolates (MDR) was 42.1%. By using spoligotyping, 35 distinct patterns were observed; 75 clinical isolates were grouped in 15 clusters (clustering rate of 79%) and 20 isolates displayed unique patterns. Five of these 20 unique patterns corresponded to orphan patterns in the SITVIT2 database, while 4 shared types containing 8 isolates were newly created. The most prevalent M. tuberculosis lineages were: Haarlem (23/95, 24.2%), ill-defined T superfamily (22/95, 23.2%), the Turkey family (19/95, 20%; previously designated as LAM7-TUR), Beijing (6/95, 6.3%), and Latin-America & Mediterranean (LAM, 5/95 or 5.3%), followed by Manu (3/95, 3.2%) and S (1/95, 1%) lineages. Four of the six Beijing family isolates (66.7%) were MDR. A combination of IS6110-RFLP and spoligotyping reduced the clustering rate from 79% to 11.5% among the drug resistant isolates. CONCLUSIONS: The results obtained showed that ill-defined T, Haarlem, the Turkey family (previously designated as LAM7-TUR family with high phylogeographical specifity for Turkey), Beijing and LAM were predominant lineages observed in almost 80% of the drug-Resistant M. tuberculosis complex clinical isolates in Ankara, Turkey.

Influence of serum on in vitro susceptibility testing of echinocandins for Candida parapsilosis and Candida guilliermondii.

Echinocandins are antifungal drugs used for the treatment of invasive candidiasis and aspergillosis. They bind to serum proteins within a rate of 96 to >99%. The effect of serum on in vitro echinocandin susceptibility tests of certain Candida and Aspergillus species was reported. This study was performed to determine the effect of human serum on in vitro susceptibility testing of echinocandins for clinical isolates of Candida parapsilosis and Candida guilliermondii, the species which generally have higher minimum inhibitor concentrations compared with other Candida species. One hundred C. parapsilosis and 20 C. guilliermondii isolates were included in the study. The susceptibility tests of caspofungin, micafungin and anidulafungin were performed using microdilution method, either in the presence or absence of 50% human serum, according to the Clinical and Laboratory Standards Institute (CLSI) M27-A3 guidelines. It was demonstrated that human serum significantly affects the in vitro susceptibility results of echinocandins for C. parapsilosis and C. guilliermondii isolates, mostly yielding an increase in MICs. The most prominent fold changes were for micafungin and anidulafungin in C. parapsilosis, and for anidulafungin in C. guilliermondii isolates. Serum influences the in vitro echinocandin susceptibility in C. parapsilosis and C. guilliermondii. The mechanism and clinical significance of this in vitro change need to be clarified.