Yurdanur Akgun

Optimum Detection Times for Bacteria and Yeast Species with the BACTEC 9120 Aerobic Blood Culture System: Evaluation for a 5-Year Period in a Turkish University Hospital

ABSTRACT We tracked and documented the time of positivity of blood cultures by using the BACTEC 9120 (Becton Dickinson Diagnostic Instrument Systems) blood culture system over a 5-year study period. A 7-day protocol of the incubation period was selected, and a total of 11,156 blood cultures were evaluated. The clinically significant microorganisms (32.95%) were isolated in 3,676 specimens. Gram-positive and -negative bacterial isolation rates were found to be 41.07 and 44.88%, respectively. Yeasts were found in 14.03% of all pathogens. Both the false-positivity and -negativity rates were very low (0.1 and 0.3%, respectively). The mean detection times for all of the pathogens were determined to be 19.45 h. Yeasts, nonfermentative gram-negative bacteria, and Brucella melitensis strains were isolated within 5 days. By taking these data into account, we decided to establish a 5-day-incubation protocol in our laboratory instead of the 7 days that are commonly used.

Frequency and risk factors of dermatophytosis in students living in rural areas in Eskişehir, Turkey.

Our study included 2384 students from five villages around Eskişehir, Turkey. We asked every student for their personal identification and also for their sanitation in order to get an idea about dermatophytosis. Samples taken from suspicious lesion were collected and inoculated onto Sabouraud dextrose agar slants. For identification of fungi which were grown, macroscopic appearance of colonies, microscopic examination and biochemical tests were used. We found suspicious lesions in 245 (10.3%) and diagnosed dermatophytosis in 86 (3.6%) of the students. The dermatophyte species were Trichophyton rubrum 37 (43%) at first, Trichophyton mentagrophytes 17 (19.8%), Microsporum canis 11 (12.8%), Microsporum gypseum 8(9.3%), Epidermophyton floccosum 6 (7%), Trichophyton verrucosum 6 (7%) and Trichophyton violaceum 1 (1.1%). Tinea pedis (59.3%) was the most frequent clinic form of dermatophytosis, followed by tinea corporis (22.1%), tinea capitis (9.3%), tinea manum (7.0%) and tinea unguium (2.3%). Older age, male gender, poor hygiene, living in dormitory, low level mother education, history of dermatophytosis within family and sanitary conditions were computed as independently variables associated with dermatophytosis infection. For prevention and control of dermatophyte infection in children living rural areas, field studies should be done and sanitary conditions should be improved.

Antifungal Activity of Caspofungin in Combination with Amphotericin B against Candida glabrata: Comparison of Disk Diffusion, Etest, and Time-Kill Methods

ABSTRACT The in vitro activities of caspofungin plus amphotericin B against 50 Candida glabrata isolates were evaluated by the time-kill, disk diffusion, and Etest methods. In vitro experiments showed a positive interaction. Even though each of these methods uses different conditions and endpoints, the results of the different methods frequently agreed.

Cigarette Smoking Increases Plasma Concentrations of Vascular Cell Adhesion Molecule-1 in Patients with Coronary Artery Disease

Cigarette smoking adversely affects endothelial function and increases risk of coronary artery disease (CAD). The pathogenesis of coronary atherosclerosis is currently thought to involve interactions between inflammatory cells and vascular endothelium. Adhesion molecules play a pivotal role in the accumulation of inflammatory cells at the endothelium. Little is known about the role of cigarette smoking in this atherosclerotic inflammatory process. The aim of this study was to evaluate the effects of cigarette smoking on the plasma concentrations of soluble vascular cell adhesion molecule-1 (VCAM-1) in patients with CAD. The soluble VCAM-1 level was quantified in smoking CAD patients (n=19) in comparison to those from patients with CAD alone (n=10). Plasma concentrations of soluble VCAM-1 were measured by enzyme-linked immunosorbent assay. The soluble VCAM-1 level was found significantly higher in smokers than in nonsmokers (32.1279 ±21.6421 vs 9.4570 ±7.8138 ng/mL, p<0.01), and in patients with previous myocardial infarction (MI) than in those without previous MI, but not significant statistically (27.7279 ±22.8813 vs 17.8170 ±15.9172 ng/mL, p>0.05). No significant difference was observed for soluble VCAM-1 levels between hypertensive and nonhypertensive patients, multivessel and one-vessel disease, or anterior and inferior MI localizations. The present study suggests that in patients with CAD, smoking leads to elevated levels of soluble VCAM-1 that may clarify one of the mechanisms of its accelerating effect on the atherosclerotic process.

Lymphadenitis Caused by Scedosporium apiospermum in an Immunocompetent Patient

A case of lymphadenitis caused by Scedosporium apiospermum in a 25-year-old immunocompetent woman had been misdiagnosed as tuberculous lymphadenitis. Clinical response to itraconazole therapy was obtained in 6 months; to our knowledge, this is the first report of lymphadenitis caused by S. apiospermum in humans.

Case Report. Rhodotorula rubra fungaemia due to use of indwelling venous catheters

Rhodotorula has been an infrequent cause of infection in humans but there have been some case reports about this systemic yeast infection. In this article, a Rhodotorula rubra fungaemia due to an indwelling catheter in a 23‐year‐old woman who had been diagnosed with non‐Hodgkins lymphoma grade IV B is described.

Evaluation of the GenoType Mycobacteria Direct assay for direct detection of the Mycobacterium tuberculosis complex obtained from sputum samples.

An increase in the prevalence of tuberculosis (TB) in recent years has accelerated the search for novel tools for the rapid diagnosis of TB infection. This study evaluated the GenoType Mycobacteria Direct (GTMD) assay (Hain Lifescience) for direct detection of the Mycobacterium tuberculosis complex (MTBC) from sputum samples and compared it with conventional methods. The GTMD test is a commercial assay produced using strip techniques and works based on a nucleic acid sequence-based amplification technique. This test allows 23S rRNA amplification-based detection of MTBC, Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium kansasii and Mycobacterium malmoense directly from decontaminated clinical samples within 6 h. In the present study, 115 sputum samples were processed to detect acid-fast bacilli (AFB) using two microscopy methods (carbol fuchsin and fluorescent staining), two culture methods [Löwenstein-Jensen (LJ) and BACTEC 12B media] and the GTMD test. The results showed that 86 of the samples were positive by direct microscopy, 84 were positive by BACTEC 12B culture, 73 were positive by LJ culture and 95 were positive by the GTMD test. All of the isolates turned out to be MTBC. Moreover, the sensitivity and specificity of the GTMD test for MTBC in patients were 97 and 58 %, respectively, taking the culture combination as the gold standard. When the test was compared with culture of samples from anti-TB-treated patients, the sensitivity and specificity for the test were 100 and 15 %, respectively. Low specificity in treated people might arise from depressed proliferation of AFB. As the two methods target the same living bacilli, the difference is obviously notable. When the culture results and clinical findings of the patients were evaluated together (true-positive specimens), the sensitivity and specificity values of the GTMD test for all patients were 97 and 90 %, respectively. However, both of these values increased to 100 % for the patients receiving anti-TB treatment. These results implied that, to determine whether the patients sputum contains living AFB, more sensitive techniques should be employed during the follow-up of the patients. These observations suggest that the GTMD method can be useful for early diagnosis of clinically and radiologically suspicious TB cases where smears are negative for Mycobacterium. In addition, the use of a GTMD test in smear-positive cases is helpful and practical in order to identify MTBC quickly. This allows more rapid treatment decisions and infection control precautions.

The investigation of parvovirus B19 infection in patients with haematological disorders by using PCR and ELISA techniques

Parvovirus B19 has a marked tropism for erythroid progenitor cells. This may lead to chronic anemia in predisposed individuals. The purpose of the study was to investigate the frequency of parvovirus B19 infections in patients with diagnosis of haematological disorders. In order to determine the diagnostic use of different markers of parvovirus B19 infection, serum specimens obtained from 79 patients with haematological disorders were tested for specific antibodies and viral DNA through the use of ELISA and PCR techniques. Evidence of parvovirus B19 infection was found in 23/79 (29.1%) patients by demonstrating viral DNA and/or specific IgM antibody. B19 infection was established in 3 of 11 patients with chronic myeloid leukemia, in 3 of 11 acute myeloid leukemia, in 2 of 11 patients with multiple myeloma, in 3 of 8 patients with Hodgkins lymphoma, in 5 of 10 patients with non-Hodgkins lymphoma, in 1 of 6 patients with myelodysplastic syndrome, in 4 of 11 patients with chronic lymphocytic leukemia, and in 2 of 11 patients with acute lymphocytic leukemia. In 4 of 23 positive patients, only parvovirus B19 DNA could be detected, while 7 patients were tested positive for both parvovirus B19 DNA and specific IgM. Nine patients were tested positive for both B19 DNA and specific IgG. In the remaining 3 positive patients only specific IgM could be detected. Due to the discrepancies between DNA and IgM results, the diagnostic procedures should include a search for specific DNA by PCR methods if specific IgM has been found to be negative.

Antibiotic prescribing patterns for sore throat infections in a university-based primary care clinic.

BACKGROUND Recent studies reveal that a high percentage (over 50%) of episodes for URTIs are treated with antibiotics, regardless of appropriateness or the necessity for prescription. We identified antibiotic prescriptions in a primary health care centre (PHC) and evaluated their suitability for sore throat infections. We also to explored whether symptoms, signs, diagnosis and antibiotics prescribed differed by gender. PATIENTS AND METHODS We collected data on all patients visiting the centre over a period of 12 weeks with a main complaint of sore throat who were prescribed antibiotics after taking a blood count and throat culture. Patients older than 16 years of age were included in the study irrespective of sex, nationality, marital status, occupation or location of residence. The chi square (χ2) statistical test was used in comparing categorical variables. A P value of <0.05 was considered significant. RESULTS During the period of study, 579 patients with upper respiratory tract infections (URTIs) presented to the health centre, from which 339 patients with a sore throat were enrolled. Of the study group, 48.7% (165) were male and 51.3% (174) female, with the majority of patients being under 30 years old (54.3%). Throat cultures were positive in 56 patients (16.5%). Most of patients were diagnosed as having pharyngitis (22.7%), and the most frequently prescribed medicine was an oral penicillin (39.1%). Two hundred eight-six patients (84.4%) had 2 or fewer Centor criteria. CONCLUSIONS Throat cultures were positive in only 16.5% of the patients prescribed antibiotics. This indicates that physicians in the health centre of the university are prescribing antibiotics inappropriately and inconsistently. This also highlights the need for more prescriber education, especially as the range of medications available to the general practitioner for prescribing increases.

Candida norvegensis fungaemia in a neutropenic patient with acute non-lymphoblastic leukaemia

We report a case of fungaemia resulting from Candida norvegensis in a patient with acute non‐lymphoblastic leukaemia‐M4 from Turkey. Candida norvegensis was isolated from two different peripheral blood samples that were taken at 2‐day intervals. Despite treatment with liposomal amphotericin B, the patient died of multi‐organ system failure.