Investigation of Metallo Beta Lactamases and Oxacilinases in Carbapenem Resistant Acinetobacter baumannii Strains Isolated from Inpatients.

BACKGROUND: Resistance to beta-lactam antibiotics is widespread among Acinetobacter strains. Plasmid-mediated metallo beta lactamases (MBL) are responsible for carbapenem resistance, as are oxacillinases (OXA). In recent years, MBL producing carbapenem-resistant strains have been reported in the world and in Turkey in increasing rates. In our country, besides the OXA 51-like enzyme which is inherent in A. baumannii strains, OXA 58-like and OXA 23-like carbapenemases producing strains have also been widely detected. In addition, Verona Imipenemase (VIM) and (IMP)-type MBL have been reported in some centers. AIMS: The aim of our study was to investigate the presence of carbapenemases in Acinetobacter strains isolated from hospitalized patients in Edirne. STUDY DESIGN: Cross-sectional study. METHODS: A total of 52 imipenem-resistant A. baumannii strains isolated between January and March 2013 were investigated. The presence of MBL was described phenotypically by the combined disk diffusion test (CDDT), double disk synergy test (DDST), MBL E-test (only performed in 28 strains) and modified Hodge test. blaIMP, blaVIM, blaGIM, blaSIM, blaSPM genes and blaOXA-23, blaOXA-51, blaOXA-40, blaOXA-58 genes were investigated by multiplex polymerase chain reaction (PCR). The blaNDM-1 gene was determined by PCR. RESULTS: By modified Hodge test, 50 strains (96%) were found to be MBL positive. Positivity of MBL was 21% by both CDDT (0.1 M EDTA) and DDST. Twenty-four of 28 strains (85.7%) were positive by MBL E-test. OXA 23-like and OXA 51-like carbapenemases were detected in all strains, but OXA 58-like and OXA 40-like carbapenemases-producing A. baumannii were not detected. Also, MBL genes were not detected by genotypic methods. CONCLUSION: Only OXA 23-like carbapenemase was responsible for carbapenem resistance in carbapenem-resistant Acinetobacter strains in Edirne. The MBL-producing Acinetobacter strain is not yet a problem in our hospital. MBL resistance was found by phenotyping tests, which must be confirmed by genotypic methods; multiplex PCR tests can be easily used for screening MBL.

[Healthcare-associated Neisseria meningitidis W135 conjunctivitis]. / Hastane ile Iliskili Neisseria meningitidis W135 Konjunktiviti.

Neisseria meningitidis is an unusual pathogen among the causes of acute bacterial conjunctivitis. Meningococcal conjunctivitis may present as primary or secondary infection, while primary meningococcal conjunctivitis may emerge as invasive or non-invasive forms. N.meningitidis W135 strain is not common in Turkey, and is rarely reported as the cause of meningitis. Moreover, no cases of conjunctivitis due to N.meningitidis W135 were reported from Turkey. In this report a case of N.meningitidis W135 conjunctivitis has been presented who acquired the infection from another patient with meningococcal meningitis by close contact in the hospital environment. A 2-month-old male infant was admitted to our hospital with poor health condition, feeding difficulty and weight loss. He was hospitalized in intensive care unit and fluid replacement started due to severe dehydration. The infant had stigmata of Down's Syndrome, and since conjunctivitis were detected on physical examination, swab samples were obtained from both eyes for direct microscopic examination and cultivation. Abundant lekocytes and gram-negative diplococci were observed in Gram-stained smears, and bacterial growth were detected in the culture from left eye samples. The isolate have been identified as N.meningitidis by conventional microbiological methods, and serotyping of the isolate yielded W135 strain. The infant was treated with systemic cefotaxime and ampicillin-sulbactam, together with topical tobramycin and gentamycin. Since no symptoms of meningitis appeared during the follow-ups, the case was diagnosed as non-invasive primary meningococcal conjunctivitis. Investigation for a probable source revealed that the infant had close contact with a six-year-old boy with high fever, unconsciousness and vomiting a week ago in the outpatient clinic of Tekirdag State Hospital. N.meningitidis was also isolated from the cerebrospinal fluid culture of probable index case with meningitis and identified as W135 strain by serotyping. Both strains isolated from these cases were found similar according to their phenotypical characteristics, however genotyping could not be performed. Since no other sources of exposure could be found, it was concluded that the infant with conjunctivitis acquired the bacteria from the other patient during their shared hospital visit. This patient is the first N.meningitidis W135 conjunctivitis case reported from Turkey.

[Assessment of efficacies of imipenem, cefoperazone-sulbactam and cefepime in rats with experimental thigh abscess model with multidrug resistant and susceptible Acinetobacter baumannii strains]. / Sefoperazon-sulbaktam, imipenem ve sefepimin antibiyoterapi etkinliklerinin çogul dirençli ve duyarli acinetobacter baumannii ile olusturulan deneysel ikili apse modelinde karsilastirilmasi.

Imipenem, cefaperazon-sulbactam and cefepime are the antibiotics of choice for the treatment of soft tissue infections due to Acinetobacter baumannii. In this study, it was aimed to determine the invivo and invitro efficacy of, these antibiotics against drug susceptible and multidrug resistant A.baumannii in an experimental abscess model. Abscess models were established in Wistar-Albino type female rats. Susceptibility tests were performed by E-test. Rats were divided randomly into four groups with eight rats in one group. Standard absorbent paper discs containing 6 log10 CFU microorganisms were used to form an abscess model. The first group was regarded as the control group and the other three groups were the study group each treated with one of the test antibiotics. Cardiac blood samples for serum antibiotic efficacy test, were obtained on the fourth day of treatment and 30 minutes after the last dose. The number of live bacteria at the area of infection was determined by colony count method. All of the three antibiotics reached sufficient concentration in sera of rats and there were no statistically important difference between the efficacies of these antibiotics (p= 0.778). In all of the antibiotic-treated groups, the weight of the abscess material were less, macroscopic views were smaller and the colony counts per gram of abscess tissue were less than the control group (p< 0.001). All antibiotics were effective against susceptible and resistant strains in vitro. No resistance was detected against imipenem, cefaperazon-sulbactam and cefepime in the course of therapy. Cefaperazone-sulbactam and cefepime were as effective as imipenem against susceptible and multi-drug resistant A.baumannii both in vivo and in vitro. Since irrational use of extended spectrum cephalosporins are frequently associated with the emergence of carbapenem resistant strains, the use of relatively narrow spectrum antibiotics should better be considered in the empirical treatment of A.baumannii infections.

[Nocardia spp. isolated from immunocompromised patients in Trakya University Medical Faculty Hospital and their antibiotic susceptibilities]. / Trakya Uuniversitesi Tip Fakültesi Hastanesinde bagisklik sistemi baskilanmis hastalardan izole edilen Nocardia türleri ve antibiyotiklere duyarliliklari.

The aims of this study were the isolation and identification of Nocardia spp. from clinical samples of immunocompromised patients and patients with underlying diseases, and determination of antibiotic susceptibilities of the isolates. A total of 234 patients (172 male, 62 female; mean age: 58.6 +/- 15.9 years) of whom 126 (53.8%) with malignancy and 108 (46.2%) with other underlying diseases (pulmonary diseases, rheumatologic disorders, diabetes mellitus, chronic renal disfunction, cerebrovascular disorders and malnutrition) were included to the study. Biochemical characteristics, growth properties and antibiotic susceptibility patterns were used for the identification of the isolates. The distribution of specimens were as follows; sputum (124), tracheal aspirate (54), pleural fluid (27), bronchoalveolar lavage (23), abscess material (7) and lung biopsy (1) material. Nocardia spp were isolated from four out of 234 patients (1.7%), and two of them were identified as N. farcinica, one as N. asteroides and one as N. otitidiscaviarum. All of the four patients have had predisposing factors (hepatocellular carcinoma/diabetes mellitus; antiphospholipid syndrome/steroid use; nephrotic syndrome/ steroid use; chronic obstructive lung disease/lung cancer?), with a mean age of 52.5 years, and of them two were male. Nocardiosis has been presented as pulmonary infection in two of the cases, and brain and soft tissue abscesses in one of each patient. Kirby-Bauer disk diffusion, E-test and broth microdilution methods were used in order to detect the antibiotic susceptibilities of the strains. All isolates were found susceptible to imipenem and amikacin and resistant to erythromycin and ampicillin. One N. asteroides isolate was found susceptible to trimetoprim-sulphamethoxazole (TMP-SMX), whereas two N. farcinica and one N. otitidiscaviarum strains were resistant. The antibiotics to which N. farcinica isolates were susceptible were ceftriaxone and cefotaxime. As a result, since there is an increase in the number of immunocompromised patients recently, Nocardia spp. should be considered in such patients, and TMP-SMX should be used with care for empirical therapy.

First case report of empyema caused by Beauveria bassiana.

Infections with Beauveria bassiana are extremely rare in humans. A 51-year-old man was admitted to hospital with the diagnosis of lung adenocarcinoma. Thoracic wall resection with lobectomy was applied and empyema has developed after prolonged air leakage. B. bassiana was isolated in pleural fluid. The patient improved without antifungal therapy after thoracotomy with securing of air leakage.

[Species and biovar distribution of Brucella isolates in Trakya University Hospital between 1997-2002]. / Trakya Universitesi Hastanesinde 1997-2002 yillari arasinda saptanan Brucella izolatlarinin tür ve biyovar dagilimi.

The aim of this study was to evaluate the species and biovar distribution of Brucella spp. isolated from blood cultures in Clinical Microbiology Laboratory of Trakya University Hospital, between 1997-2002. A total of 48 Brucella spp. have been isolated from 14.815 patients (0.3%), and the strains were identified according to CO2 requirement, H2S production, basic fuchsin and thionin sensitivity, lysis by Tbilisi phages, and presence of agglutination with monospecific A and M antisera. As a result, 47 (97.9%) isolates were identified as B. melitensis, and one as B. abortus (2.1%). Forty two (89.4%) of B. melitensis isolates were biovar 3, and five (10.6%) were biovar 1, while the single isolate of B. abortus was identified as an atypical strain.