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Determination of antimicrobial susceptibility patterns and inducible clindamycin resistance in Staphylococcus aureus strains recovered from southeastern Turkey

BACKGROUND In this study, we determined the susceptibility patterns of Staphylococcus aureus strains to various antimicrobials and prevalence of inducible clindamycin resistance (ICR) in these isolates. METHODS Two hundred and one S aureus strains, isolated from various clinical samples, were included in the study. Antibiotic susceptibilities were studied by disc diffusion method on the basis of the guidelines by the Clinical and Laboratory Standards Institute. The disc diffusion induction test (D test) was applied to determine ICR resistance among erythromycin-resistant S aureus isolates. RESULTS Of the 201 S aureus strains, 101 (50.2%) were resistant to methicillin. All strains were susceptible to vancomycin, teicoplanin, quinupristin/dalfopristin, and linezolid. It was found that 54 (53.4%) methicillin-resistant S aureus (MRSA) strains were erythromycin resistant, and 40 (39.6%) of them showed constitutive clindamycin resistance. ICR was detected in seven (6.9%) MRSA strains. It was found that 13 (13.0%) methicillin-susceptible S aureus (MSSA) strains were erythromycin resistant. Constitutive clindamycin resistance was seen in one (1.0%) MSSA strain, and ICR was detected in 10 (10.0%) cases. CONCLUSION There was a high rate of methicillin resistance among S aureus strains in our hospital. However, no statistically significant difference of ICR was observed between MRSA and MSSA strains (p=0.434) or between inpatients and outpatients (p=0.804). It was concluded that ICR should be routinely evaluated in each S aureus case to avoid therapy failure among patients.

In Vitro Susceptibility of Candida Species to Four Antifungal Agents Assessed by the Reference Broth Microdilution Method

This study was performed to determine the distribution of Candida species isolated from the blood cultures of the patients hospitalized in our hospital and to investigate their antifungal susceptibility. Candida strains were identified at species level by using classical methods and API ID 32C (bioMerieux, France) identification kits. The susceptibility of the strains to amphotericin B, fluconazole, voriconazole, and caspofungin was evaluated by using the reference broth microdilution method in document M27-A3 of the Clinical and Laboratory Standards Institute. Of the 111 Candida strains isolated, 47.7% were identified as C. albicans and 52.3% as non-albicans Candida strains. The MIC ranges were 0.03–1 μg/mL for amphotericin B, 0.125–≥64 μg/mL for fluconazole, 0.03–16 μg/mL for voriconazole, and 0.015–0.25 μg/mL for caspofungin. All Candida strains were susceptible to amphotericin B and caspofungin. 10.8% isolates were resistant to fluconazole and 8.1% isolates were dose-dependent susceptible. While 0.9% isolate was resistant to voriconazole, 0.9% isolate was dose-dependent susceptible. In our study, C. albicans and C. parapsilosis were the most frequently encountered agents of candidemia and it was detected that voriconazole with a low resistance rate might also be used with confidence in the treatment of infections occurring with these agents, primarily besides amphotericin B and caspofungin.

Prevalence of Hepatitis E Virus Antibodies in Patients with Chronic Hepatitis B and Chronic Hepatitis C

Objectives: To investigate the prevalence of hepatitis E virus (HEV) among patients with chronic hepatitis B and chronic hepatitis C, serum samples were collected between January and December 2004 from patients with chronic hepatitis B and chronic hepatitis C. Methods: There were 190 adult patients with chronic hepatitis B virus (HBV) and 174 with chronic hepatitis C virus (HCV) infection in the study group. As the control group, a cohort of 178 age- and sex-matched individuals without known liver disease was selected. Results: Anti-HEV IgG antibodies were positive in 26/190 (13.7%) of chronic HBV and 94/174 (54%) of chronic HCV patients. In the control group anti-HEV positivity was 15.7% (28/178). There was no difference in the percentage of chronic HBV patients and control group who were positive for anti-HEV antibody, but the presence of HEV infection was significantly higher in chronic HCV patients. Conclusions: Our findings suggest that HEV and HCV might share a common route of transmission in our region. We recommend that preventive measures against HEV should be undertaken in chronic HCV patients as superinfection with HEV can cause a more severe pattern of disease in chronic hepatitis patients.

Coryneform Bacteria Isolated from Blood Cultures and Their Antibiotic Susceptibilities

We aimed to determine the types of corynebacteria isolated from the blood of patients at Gaziantep University Hospital, Turkey, and their antibiotic susceptibilities. Between February 1999 and June 2001, 3530 blood samples were cultured, of which 915 were found to be positive, and these were further investigated in the bacteriology laboratory. Among positive blood cultures, coryneform bacteria were identified in 31 (3.4%) isolates. Of these, 16 (51.6%) were Corynebacterium jeikeium, six (19.4%) were Corynebacterium striatum, four (12.9%) were Corynebacterium amycolatum, two (6.5%) were Cellulomonas species, two (6.5%) were Corynebacterium afermentans and one isolate (3.2%) was Corynebacterium propinquum. Antibiotic susceptibility tests showed that C. jeikeium was resistant to various antibiotics, whereas all isolates were susceptible to vancomycin and teicoplanin. This study illustrates the importance of taking coryneform bacteria into consideration when culturing blood samples. The need to identify the species and determine its antibiotic sensitivity is emphasized.

Prevalence and genotype distribution of human papillomavirus in non-neoplastic cervical tissue lesion: cervical erosion.

Human papillomavirus (HPV) infection is the commonest sexually transmitted infection, which is associated with various clinical conditions, ranging from asymptomatic infection to malignant disease of the cervix. The aim of this study was to evaluate the prevalence and genotypic distribution of HPV in women with cervical erosion and to compare the results with those in women with a clinically normal cervix. A further aim was to establish the association between HPV infection and cervical cytology results in women with and without cervical erosion. Cervical samples were collected by liquid‐based method and consecutively evaluated for the presence of HPV DNA and for cervical cytology. HPV DNA was tested by a nested polymerase chain reaction (PCR) and typed by reverse dot blot genotyping. Cytological classification was made according to Bethesda 2001 criteria. The overall HPV prevalence was 16.9%; HPV DNA was positive in 20.2% of women with cervical erosion and 12.8% in women with normal cervix (P < 0.05). Multiple infections were found in 34.1% of the HPV‐positive women. Commonest types were HPV 18 (32.9%), HPV 16 (29.5%), HPV 54 (20.5%), and HPV 6 (17%). Cervical cytology results were abnormal for 5.2% of women with cervical erosion and for 1.3% with clinically normal cervix (P < 0.05). This study detected a high prevalence of HPV infection in women with cervical erosion compared to women with a normal cervix. This data may contribute to the HPV epidemiology in the southeastern Turkey. It is recommended that women with cervical erosion should be given priority in HPV screening programs. J. Med. Virol. 83:1997–2003, 2011.

Demonstration of Chlamydophila pneumoniae, Mycoplasma pneumoniae, Cytomegalovirus, and Epstein-Barr virus in atherosclerotic coronary arteries, nonrheumatic calcific aortic and rheumatic stenotic mitral valves by polymerase chain reaction.

OBJECTIVE The aim of this study was to investigate whether bacterial and viral infectious agents can be demonstrated in atherosclerotic lesions of patients with coronary artery disease (CAD) as well as in stenotic aortic and mitral valves from patients undergoing heart valve replacement. METHODS In this cross-sectional study, the presence of Chlamydophila pneumoniae, Mycoplasma pneumoniae, Cytomegalovirus (CMV), and Epstein-Barr virus (EBV) was investigated by polymerase chain reaction in atherosclerotic and non-atherosclerotic vascular samples taken from patients undergoing coronary artery bypass surgery due to CAD, and from patients undergoing aortic (AVR) and/or mitral valve replacement (MVR) secondary to valvular stenosis. For statistical analyses ANOVA, Chi-square test or Fishers exact test were used. RESULTS The presence of C. pneumoniae, M. pneumoniae, and CMV in atherosclerotic versus non-atherosclerotic samples was as follows: 30% vs. 16.7% (p=0.222), 6.7% vs. 3.3% (p=0.554), and 10% vs. 0% (p=0.076), respectively. In valve group, same pathogens were present in AVR and MVR patients as follows: 24.2% vs. 21.4% (p=0.773), 9.1% vs. 7.1% (p=0.758), and 21.2% vs. 11.9% (p=0.275). EBV DNA was not detected in any of vascular specimens, but in one (3%) patient with AVR (p=0.256). CONCLUSION Our results suggest that C. pneumoniae, M. pneumoniae, and CMV are present with similar frequency both in atherosclerotic and non-atherosclerotic vessels. We conclude that although non-atherosclerotic, vascular samples of CAD patients are invaded by infectious agents as like as atherosclerotic vessels. We further conclude that C. pneumoniae, M. pneumoniae, and CMV are present in stenotic aortic and mitral valves and atherosclerotic tissues with similar frequency indicating that atherosclerosis and valvular stenosis might share a common etiology related to infection.

Evaluation of Two Different Hand Hygiene Procedures during Routine Patient Care

In this study, the antimicrobial efficacy of hand washing (HW) and hand washing plus rubbing with an alcohol-based solution (HWR) on numbers of total and transient flora colonies on the hands of healthcare workers (HCWs) during routine patient care was assessed. Samples were collected, using a standard bag broth technique, from the hands of 154 HCWs, before and immediately after carrying out a hand hygiene procedure. The numbers of total and transient flora colonies per plate were counted and transient pathogens were identified. A significant statistical difference between ward speciality was detected with respect to the isolation rate of transient flora. Transient hand flora were recovered from 25.3% of HCWs before carrying out the hand hygiene procedure. With respect to the disappearance and prevention of regrowth of transient flora after hand hygiene, the HWR technique was significantly more effective than HW. In conclusion, a disinfectant should be added to the hand washing process to achieve optimum protection against nosocomial infections in routine hospital practice.

In vitro efficacy of various antibiotic combinations against Pseudomonas aeruginosa isolates

Objective Pseudomonas aeruginosa is one of the leading causes of nosocomial infection. The present study tested the in vitro efficacy of ceftazidime or imipenem combined with amikacin, levofloxacin and colistin in P.aeruginosa isolates. Methods P.aeruginosa strains, isolated from clinical samples, were assessed for antibiotic susceptibility using the disc diffusion method. Antibiotic combination tests were performed using minimum inhibitory concentration (MIC) test strips and the sum of the Fractional Inhibitory Concentration (ΣFIC) index was used to assess synergy. Results Out of 60 isolated P.aeruginosa strains, 100% were susceptible to colistin and 26.7% (16 strains) were multidrug resistant. MIC50 and MIC90 values were 2 and 32 µg/ml for imipenem; 1.5 and 24 µg/ml for ceftazidime; 3 and 8 µg/ml for amikacin; 0.38 and 32 µg/ml for levofloxacin; 1 and 1.5 µg/ml for colistin, respectively. Antagonism was not found in any of the antibiotic combinations tested. The amikacin–ceftazidime combination was found to have a synergistic effect in 15% of the strains, but no synergistic effect was detected for other combinations. Conclusions In Pseudomonas infection, alternative treatment options using different antibiotic combinations should be tested in vitro and findings should be confirmed by clinical studies.

Genotyping Leishmania promastigotes isolated from patients with cutaneous leishmaniasis in south-eastern Turkey

Objective Cutaneous leishmaniasis (CL) is a significant disease in south-eastern Anatolia because it is prevalent among Syrian refugees. We identified the causative Leishmania species in CL patients using molecular methods. Methods Novy–MacNeal–Nicolle medium was inoculated with aspirated fluid from suspected CL lesions and tested for amastigotes with Giemsa staining. PCR amplified the internal transcribed spacer 1 (ITS1) of the Leishmania genome in cultures containing Leishmania promastigotes from 100 patients, which were genotyped with a restriction fragment length polymorphism (RFLP) analysis. A phylogenetic tree was constructed from ITS1 sequences of 95 culture fluid samples from these patients. Results Leishmania amastigotes were detected in 92% of cultures with growth. Leishmania promastigotes were typed as Leishmania tropica with both PCR–RFLP and sequencing. Conclusions Identification of L. tropica as the causative agent of CL in our region allows the clinical course to be predicted, and guides treatment decisions and preventive measures.

Investigating the presence of fungal agents in febrile neutropenic patients using different microbiological, serological, and molecular methods

This study aimed to investigate fungal agents in febrile neutropenic patients with hematological malignancies. Direct microscopy and cultures were performed on clinical samples collected from febrile neutropenic episodes. The galactomannan (GM) antigen was tested using enzyme-linked immunosorbent assays, and Aspergillus fumigatus and Candida albicans deoxyribonucleic acid (DNA) assessed using real-time polymerase chain reaction (PCR) in consecutive serum samples. Of the 199 episodes investigated, 1.5% were classified as definite invasive aspergillosis (IA), 4.0% as IA with high probability, and 4.0% as IA with low probability. Additionally, candidaemia was detected in eight episodes (4.1%). The GM antigen was found negative for 86.4% of episodes, as one positive for 7.0% of episodes, as two or more consecutive positives for 5.5% of episodes, and as positive in any two serum samples in 1.0% of episodes. While no C. albicans DNA was detected in 98.5% of 199 episodes, one positive result was obtained in 1.0% of episodes, and two or more consecutive positives in 0.5% of episodes. A. fumigatus PCR results were found negative in 81.9% of episodes, as one positive in 16.1% of episodes, as positive in any two serum samples in 1.0% of episodes, and consecutively positive in 1.0% of episodes. GM antigen tests were found consecutively positive in all three patients diagnosed as having definite IA. These findings indicate that conventional, serological, and molecular methods should be used in combination to detect fungal agents in febrile neutropenic patients.