Secondary bacterial infections and antimicrobial resistance in COVID-19: comparative evaluation of pre-pandemic and pandemic-era, a retrospective single center study.

PURPOSE: In this study, we aimed to evaluate the epidemiology and antimicrobial resistance (AMR) patterns of bacterial pathogens in COVID-19 patients and to compare the results with control groups from the pre-pandemic and pandemic era. METHODS: Microbiological database records of all the COVID-19 diagnosed patients in the Ege University Hospital between March 15, 2020, and June 15, 2020, evaluated retrospectively. Patients who acquired secondary bacterial infections (SBIs) and bacterial co-infections were analyzed. Etiology and AMR data of the bacterial infections were collected. Results were also compared to control groups from pre-pandemic and pandemic era data. RESULTS: In total, 4859 positive culture results from 3532 patients were analyzed. Fifty-two (3.59%) patients had 78 SBIs and 38 (2.62%) patients had 45 bacterial co-infections among 1447 COVID-19 patients. 22/85 (25.88%) patients died who had bacterial infections. The respiratory culture-positive sample rate was 39.02% among all culture-positive samples in the COVID-19 group. There was a significant decrease in extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales (8.94%) compared to samples from the pre-pandemic (20.76%) and pandemic era (20.74%) (p = 0.001 for both comparisons). Interestingly, Acinetobacter baumannii was the main pathogen in the respiratory infections of COVID-19 patients (9.76%) and the rate was significantly higher than pre-pandemic (3.49%, p < 0.002) and pandemic era control groups (3.11%, p < 0.001). CONCLUSION: Due to the low frequency of SBIs reported during the ongoing pandemic, a more careful and targeted antimicrobial prescription should be taken. While patients with COVID-19 had lower levels of ESBL-producing Enterobacterales, the frequency of multidrug-resistant (MDR) A. baumannii is higher.

The Utility of Colistin in Multiple Drug-Resistant Pseudomonas aeruginosa Bacterial Keratitis in a Kaposi's Sarcoma Patient

A 71-year-old male patient presented with decreased visual acuity, redness, and discharge in his right eye for 5 days. He had undergone evisceration of his left eye several years earlier. Before presentation, he had received chemotherapeutic agents for Kaposi's sarcoma of the scalp. Slit-lamp examination revealed severe hypopyon and an extensive corneal ulcer with surrounding infiltrate, which extended to the deep stroma. Microbiological evaluation identified the causative agent to be multiple drug-resistant Pseudomonas aeruginosa. Based on culture and susceptibility results, the patient was started on topical colistin 0.19% instilled hourly. Complete resolution of keratitis with residual corneal scarring was observed. In recent years, there has been an increase in drug resistance in P. aeruginosa keratitis. The lack of new antimicrobial agents against these resistant strains has led clinicians to reconsider colistin, which is an old drug. In this report, we aimed to stress the utility of colistin in multiple drug-resistant P. aeruginosa bacterial keratitis in a Kaposi's sarcoma patient.

Investigation of the Antimicrobial Susceptibility Profile, Virulence Genes, and Epidemiologic Relationship of Clinical Salmonella Isolates.

OBJECTIVES: The objectives of this study were to investigate the epidemiologic relationship, prevalence of the beta-lactamase and virulence genes of clinical ampicillin-resistant Salmonella enterica. MATERIALS AND METHODS: In vitro ampicillin susceptibilities of 117 Salmonella enterica isolates obtained between 2011-2012 from Ege University Hospital, Bacteriology Laboratory of Medical Microbiology Department were examined using disc diffusion assays in accordance with the CLSI guidelines. The MIC levels in the ampicillin-resistant bacteria were determined using the broth microdilution method. The resistant strains were serotyped by the Public Health Institution. Epidemiologic relations of resistant strains were evaluated using ERIC-PCR. The presence of beta-lactamase genes and virulence factors were detected using PCR. RESULTS: The 117 S. enterica strains had ten isolates that were resistant to ampicillin, and the MIC range of ampicillin was found as 512-128 µg/mL. Ampicillin-resistant strains were susceptible to nalidixic acid, ciprofloxacin, cefotaxime, sulfamethoxazole/trimethoprim. Four different serotypes were identified and isolates were grouped into seven clusters. Five isolates carried blaTEM , and two carried the blaCTX-M gene. However, it was determined that blaSHV and blaPER genes did not exist in these strains. Virulence genes invA, pipD, and sopB were found in all isolates. sifA, pefA, and sopE genes were found in seven, four, and three isolates, respectively. CONCLUSION: Our data suggest that the rate of ampicillin resistance in S. enterica isolates was 8.5% in the two year period, but this ratio was generally lower than rates abroad. blaCTX-M and blaTEM genes could be responsible for ampicillin resistance. The blaSHV gene, which is highly prevalent in our country, was not found in any strains. sopB and pipD genes, which might be associated with beta-lactam resistance, were found in all strains. It is also noteworthy that the three isolates containing the sopE gene, which is associated with epidemic cases, were of the same serotypes and epidemiologic clusters.

Antibacterial resistance patterns and incidence of hospital-acquired Staphylococcus aureus bacteremia in a tertiary care educational hospital in Turkey: a perspective from 2001 to 2013

Background/aim: Staphylococcus aureus is an important nosocomial pathogen and a successful antimicrobial-resistance developer. In this study we retrospectively evaluated the resistance patterns and incidence of microbiologically confirmed nosocomial bacteremia (MCNB) related S. aureus strains between 2001 and 2013. Materials and methods: Any patient in whom S. aureus was isolated in at least one set of blood cultures (sent to the bacteriology laboratory 72 h after hospital admission) was considered to have MCNB. Results: The methicillin-resistant S. aureus (MRSA) rate in 2001 was 73.8% whereas it was 36.2% in 2013. When the 2001-2003 and 2011?2013 periods were compared, resistance to oxacillin, levofloxacin, gentamicin, erythromycin, and clindamycin decreased significantly (P < 0.05). When we evaluated the total S. aureus, MRSA, and methicillin-sensitive S. aureus (MSSA) bacteremia rates per 1000 days and 1000 patients, there was an increase in the 2004?2005 period, which was followed by a slight decrease until 2013 (P < 0.05). There was a plateau in MCNB-related S. aureus rates between 2008 and 2011. Conclusion: There was a decrease in overall S. aureus and MRSA bacteremia incidence as well as MRSA rates except for a plateau between 2008 and 2011. This steady decrease in the resistance rates is most probably due to the 2003 budget application and application of antimicrobial stewardship.

[Investigation of bacterial and viral etiology in community acquired central nervous system infections with molecular methods]. / Toplum kökenli santral sinir sistemi enfeksiyonlarinda bakteriyel ve viral etiyolojinin moleküler yöntemlerle degerlendirilmesi.

In this multicenter prospective cohort study, it was aimed to evaluate the bacterial and viral etiology in community-acquired central nervous system infections by standart bacteriological culture and multiplex polymerase chain reaction (PCR) methods. Patients hospitalized with central nervous system infections between April 2012 and February 2014 were enrolled in the study. Demographic and clinical information of the patients were collected prospectively. Cerebrospinal fluid (CSF) samples of the patients were examined by standart bacteriological culture methods, bacterial multiplex PCR (Seeplex meningitis-B ACE Detection (Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Listeria monocytogenes, Group B streptococci) and viral multiplex PCR (Seeplex meningitis-V1 ACE Detection kits herpes simplex virus-1 (HSV1), herpes simplex virus-2 (HSV2), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein Barr virus (EBV) and human herpes virus 6 (HHV6)) (Seeplex meningitis-V2 ACE Detection kit (enteroviruses)). Patients were classified as purulent meningitis, aseptic meningitis and encephalitis according to their clinical, CSF (leukocyte level, predominant cell type, protein and glucose (blood/CSF) levels) and cranial imaging results. Patients who were infected with a pathogen other than the detection of the kit or diagnosed as chronic meningitis and other diseases during the follow up, were excluded from the study. A total of 79 patients (28 female, 51 male, aged 42.1 ± 18.5) fulfilled the study inclusion criteria. A total of 46 patients were classified in purulent meningitis group whereas 33 were in aseptic meningitis/encephalitis group. Pathogens were detected by multiplex PCR in 41 patients. CSF cultures were positive in 10 (21.7%) patients (nine S.pneumoniae, one H.influenzae) and PCR were positive for 27 (58.6%) patients in purulent meningitis group. In this group one type of bacteria were detected in 18 patients (14 S.pneumoniae, two N.meningitidis, one H.influenzae, one L.monocytogenes). Besides, it is noteworthy that multiple pathogens were detected such as bacteria-virus combination in eight patients and two different bacteria in one patient. In the aseptic meningitis/encephalitis group, pathogens were detected in 14 out of 33 patients; single type of viruses in 11 patients (seven enterovirus, two HSV1, one HSV2, one VZV) and two different viruses were determined in three patients. These data suggest that multiplex PCR methods may increase the isolation rate of pathogens in central nervous system infections. Existence of mixed pathogen growth is remarkable in our study. Further studies are needed for the clinical relevance of this result.

[Investigation of carbapenemases in carbapenem-resistant Escherichia coli and Klebsiella pneumoniae strains isolated in 2014 in Turkey]. / Türkiye'de 2014 yili içinde izole edilen karbapeneme dirençli Escherichia coli ve Klebsiella pneumoniae izolatlarinda karbapenemaz varliginin arastirilmasi.

Carbapenems are the choice of treatment in infections caused by multidrug resistant Enterobacteriaceae. In recent years carbapenem-resistant Enterobacteriaceae isolates due to carbapenemases have been increasingly reported worldwide. Multicenter studies on carbapenemases are scarce in Turkey. The aim of this study was to determine the distribution of carbapenemases from different parts of Turkey as a part of the European Survey of Carbapenemase Producing Enterobacteriaceae (EuSCAPE) project. Beginning in November 2013, carbapenem-resistant isolates resistant to at least one of the agents, namely imipenem, meropenem, and ertapenem were sent to the coordinating center. Minimum inhibitory concentrations for these carbapenems were determined by microdilution tests following EUCAST guidelines. Production of carbapenemase was confirmed by combination disk synergy tests. Types of carbapenemases were investigated using specific primers for VIM, IMP; NDM, KPC and OXA-48 genes by multiplex polymerase chain reaction. In a six month period, 155 suspected carbapenemase-positive isolates were sent to the coordinating center of which 21 (13.5%) were E.coli and 134 (86.5%) were K.pneumoniae. Nineteen (90.5%) strains among E.coli and 124 (92.5%) strains among K.pneumoniae were shown to harbour at least one carbapenemase gene by molecular tests, with a total of 92.3% (143/155). Carbapenemases were determined as a single enzyme in 136 strains (OXA-48: 84.6%; NDM: 6.3%; VIM: 2.8%; IMP: 1.4%) and as a combination in seven isolates (OXA-48 + NDM: 2.1%; OXA-48 + VIM: 2.1%; VIM + NDM: 0.7%). KPC was not detected in any of the isolates. According to the microdilution test results, resistance to imipenem, meropenem and ertapenem in OXA-48 isolates were 59.5%, 52.9% and 100%, respectively. The combination disk synergy test was 100% compatible with the molecular test results. As most of the OXA-48 producing isolates were susceptible to meropenem but all were resistant to ertapenem, ertapenem seems to be the most sensitive agent in screening carbapenemases in areas where OXA-48 is prevalent and phenotypic combination tests can be useful in centers where molecular tests are not available.

[Risk factors for gastrointestinal colonization by ESBL-producing Klebsiella pneumoniae and Escherichia coli in anaesthesiology and reanimation intensive care unit]. / Anesteziyoloji ve reanimasyon yogun bakim ünitesinde GSBL üreten Klebsiella pneumoniae ve Escherichia coli kolonizasyonu için risk faktörleri.

In this study it was aimed to investigate the risk factors for gastrointestinal colonization by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli in intensive care unit (ICU) of anaesthesiology and reanimation, Ege University Faculty of Medicine, Izmir, Turkey. This study was performed prospectively on adult patients hospitalized in ICU of anaesthesiology and reanimation and rectal swab cultures were performed in all patients in the first 48 hours of hospitalization and every one week until discharge or death. Samples were transported to the laboratory in Stuart transport medium and were cultured on two EMB agar plates (one including 4 mg/L ceftazidime) and incubated for 48 hours. E.coli and K.pneumoniae isolates were identified by conventional methods. Antibiotic susceptibility tests were performed by disc diffusion method on Mueller Hinton agar and interpreted according to CLSI guidelines. ESBL was confirmed by double disc synergy test. A total of 140 patients (49 female 91 male; age range: 18-83 years, mean age: 56.3 years) were evaluated, and 41 (29.3%) of the patients were found to be colonized with ESBL positive E.coli (n= 39) or K.pneumoniae (n= 2). The mean time for colonization was 11.15 ± 10.91 (range between 2-39) days. Age and gender of the patients and antibiotic consumption before or during the stay in ICU of anaesthesiology and reanimation were not found to be associated with colonization (p> 0.05). However length of ICU of anaesthesiology and reanimation stay in colonized patients was longer than non-colonized patients (27.59 ± 22.52 vs. 17.78 ± 11.74 days; p< 0.05). Infectious episodes developed in 22% (9/41) of the colonized cases and three of the nine strains were isolated from the blood cultures, five from the urine cultures and one from both blood and bronchoalveolar lavage cultures. ESBL-positive E.coli or K.pneumoniae colonization was found as an independent risk factor for the development of infection (9/41 vs. 4/99 cases; p= 0.002). Forward logistic regression analysis revealed that diabetes mellitus, immunosuppresive drug use and length of intubation were associated with ESBL-positive E.coli or K.pneumoniae colonization (p< 0.05). The results of this study indicated that the risk of development of infection was significantly high in intensive care patients colonized by ESBL positive E.coli and K.pneumoniae and the identification of the related risk factors was critically important for the establishment of effective control measures.

Risk factors for microbial contamination of peripheral blood stem cell products.

BACKGROUND: Despite the well-known contamination rates and presence of microbial agents in stem cell products, the risk factors affecting microbial contamination have not been well described. STUDY DESIGN AND METHODS: In a 12-year period, we retrospectively reviewed culture results of peripheral blood stem cell products with the intent of identifying risk factors for microbial contamination. RESULTS: Microbial contamination was detected in 28 (5.7%) products of the postprocessing period and in 18 (3.66%) products of the postthawing period. Large-volume leukapheresis (LVL; odds ratio [OR], 5.85; 95% confidence interval [CI], 1.52-22.49; p = 0.01) and high numbers of stem cell culture sampling (OR, 1.4; 95% CI, 1.03-1.91; p = 0.03) were found to be risk factors for postprocessing bacterial contamination. The presence of postprocessing bacterial contamination was a risk factor for postthawing (OR, 28.89; 95% CI, 6.67-125.15; p < 0.001) and posttransplant (OR, 3.25; 95% CI, 1.24-8.50; p = 0.01) microbial growth. In transplants that were performed using contaminated products, the same pathogen was detected in 20% of patients and different pathogens were found in 35% of patients. CONCLUSION: Cultures should be carefully monitored in LVL products and in samples with high numbers of cultures performed. Growth of different bacterial pathogens must be considered in transplants that are performed with contaminated products.

[Comparative evaluation of in vitro activities of carbapenems against gram-negative pathogens: Turkish data of COMPACT study]. / Karbapenemlerin Gram-Negatif Patojenlere Karsi In Vitro Aktivitelerinin Karsilastirmali Degerlendirmesi: COMPACT Çalismasi Türkiye Verisi.

The aim of this study was to determine the in vitro activities of doripenem, imipenem, and meropenem against clinical gram-negative isolates. A total of 596 clinical isolates were obtained from intensive care unit (ICU) and non-ICU patients in 10 centers over Turkey between September-December 2008. The origin of the isolates was patients with nosocomial pneumonia (42.4%), bloodstream infections (%40.4), and complicated intraabdominal infections (17.1%). Of the isolates, 51.8% were obtained from ICU patients. The study isolates consisted of Pseudomonas spp. in 49.8%, Enterobacteriaceae in 40.3%, and other gram-negative agents in 9.9%. The minimum inhibitory concentrations (MIC) for doripenem, imipenem and meropenem were determined for all isolates in each center using Etest® strips (AB Biodisk, Solna, Sweden). Of the isolates, 188 (31.5%) were resistant to at least one of the carbapenems. MIC50 of doripenem against Pseudomonas spp. Was 1 mg/L which was similar to that of meropenem and two-fold lower than imipenem. Susceptibility to carbapenems in P.aeruginosa was 64% for doripenem at an MIC level of 2 mg/L, 53.9% and 63% for imipenem and meropenem at an MIC level of 4 mg/L, respectively. Doripenem and meropenem showed similar activity with the MIC90 of 0.12 mg/L whereas imipenem was four-fold less active at 0.5 mg/L. Against other gramnegative pathogens, mostly Acinetobacter spp., MIC50 was 8 mg/L for doripenem and 32 mg/L for other two carbapenems. P.aeruginosa isolates were inhibited 84.2% with doripenem and 72.1% with meropenem at the MIC level of 8 mg/L. Doripenem generally showed similar or slightly better activity than meropenem and better activity than imipenem against pathogens collected in this study. Against Pseudomonas spp., doripenem was the most active of the three carbapenems. Doripenem and meropenem were equally active against Enterobacteriaceae and at least four-fold more active than imipenem. It was concluded that doripenem seemed to be a promising agent in the treatment of nosocomial pneumonia, blood stream infections and intraabdominal infections particularly in patients who were under risk of developing antimicrobial resistance.

[A case of cerebral abscess due to methicillin-resistant Staphylococcus aureus which is treated with linezolid + rifampin combination]. / Linezolid + rifampisin kombinasyonu ile tedavi edilen metisiline dirençli Staphylococcus aureus'un neden oldugu beyin apsesi olgusu.

Methicillin-resistant Staphylococcus aureus (MRSA) is a rare cause of cerebral abscesses, however it is a relatively more common etiologic agent in post-neurosurgical abscesses and the main antibacterial therapy option is vancomycin. In this report, a case of brain abscess due to MRSA which did not respond neither to moxifloxacin + vancomycin nor vancomycin + rifampin combination therapies, and merely treated by linezolid + rifampin combination, has been presented. Fifty-one years old female patient who was operated 40 days ago for subarachnoid bleeding and aneurysm in middle cerebral artery bifurcation, was hospitalized due to purulent leakage from the operation area. She did not have fever and her physical examination, including the neurologic system, was normal. Computerized tomography revealed an approximately 1 cm lesion compatible with subdural empyema and cerebral abscess in the right frontoparietal area in supratentorial sections. The patient was operated for wound revision and moxifloxacin was initiated. Since the operation materials revealed MRSA growth, vancomycin (4 x 500 mg, IV) was added to the treatment. The isolate was identified by conventional methods, and antibiotic susceptibility test performed by disk diffusion method showed that it was susceptible to levofloxacin, linezolid, rifampin, vancomycin and teicoplanin. Since no clinical response was obtained in two weeks, moxifloxacin was switched to rifampin (300 mg 1 x 2). On the 10th day of vancomycin + rifampin therapy, radiological findings showed development of cerebritis and therefore vancomycin was changed with linezolid (2 x 600 mg, IV). The control CT of the patient revealed regression of the brain lesion and linezolid + rifampin treatment continued for six weeks. The patient did not develop any hematological, liver or renal toxicity during the therapy and the radiological findings regressed. No relapse were detected in the one year follow-up period. This case suggested that linezolid might be a treatment alternative in the therapy of vancomycin-refractory MRSA brain abscess.

[Streptococcus equisimilis associated septic arthritis/prosthetic joint infection]. / Streptococcus equisimilis'e bagli septik artrit/protez enfeksiyonu olgusu.

Group C streptococci are flora members of skin, nasopharynx, gastrointestinal and genitourinary systems. They are rare causes of human pharyngitis, arthritis, pneumonia, meningitis and bacteremia. In this report, a 71-years old male patient with Streptococcus equisimilis arthritis/prosthetic joint infection has been presented. The patient was admitted to the emergency service with the complaints of erythema, swelling and tenderness on right knee which had total knee prosthesis. Examination of synovial fluid punction sample yielded abundant amount of leukocytes (> 1000 cells/mm3). Empirical ampicillin-sulbactam (1 g q6h, parenterally) therapy was initiated. Bacteria which have been cultivated from synovial fluid specimen were identified as S. equisimilis. The isolate was found to be susceptible to penicilin, erythromycin and teicoplanin, and resistant to chloramphenicol and tetracycline. Although clinical presentation improved during the first ten days, symptoms recurred after the 10th day and the therapy was switched to teicoplanin. The recurrence was thought to be the result of antibiotic tolerence. The patient was treated successfully with teicoplanin, and no relapse or reinfection was observed during one year of follow-up. To our knowledge this is the first case of S. equisimilis arthritis reported from Turkey and first case of S. equisimilis associated prosthetic joint infection.

[A rare cause of catheter-related bacteremia: Rhizobium radiobacter]. / Nadir bir katetere bagli bakteriyemi etkeni: Rhizobium radiobacter.

Rhizobium spp. (R. radiobacter, R. rhizogenes, R. rubi, R. vitis) are aerobic, motile, non-spore forming, oxidase-positive, gram-negative bacilli. Although they are mostly plant pathogens, R. radiobacter may cause human infections. The aim of this report was to present a case of R. radiobacter bacteremia treated with levofloxacin. Twenty-seven year old male patient had fever after receiving chemotherapy due to osteosarcoma. The infection focus could not be detected in the initial physical examination. Blood cultures were obtained from peripheral veins and central catheter and levofloxacin (500 mg/day) was started as empirical therapy. His fever resolved on the next day. Meanwhile cultures of blood (Bact/Alert automated systems, bioMerieux, Durham, NC) obtained from peripheral veins and central catheters yielded bacteria which were identified as R. radiobacter by VITEK 2 (bioMerieux Inc, Mercy L'etoil, France). The strain was resistant to amikacin and sensitive to ceftazidime, ciprofloxacin, imipenem, meropenem and piperacillin/tazobactam. The patient was diagnosed as catheter-related bacteremia and the treatment was continued for 14 days. His catheter was not removed since subsequent cultures did not reveal any bacterial growth. In conclusion this case suggests that R. radiobacter may cause infections especially in immunocompromised patients with catheters or prosthetic devices. To our knowledge this is the first R. radiobacter case reported from Turkey and the first case of R. radiobacter bacteremia reported to be treated with levofloxacin in the literature.

[Extended-spectrum beta-lactamase production and antimicrobial resistance patterns of Klebsiella pneumoniae strains isolated from nosocomial bacteremic patients: evaluation of the results of 2001-2005 period]. / Hastane kökenli bakteriyemi etkeni olan Klebsiella pneumoniae suslarinin direnç paternleri ve genislemis spektrumlu beta laktamaz uretimi: 2001-2005 yillarinin degerlendirilmesi.

Extended spectrum beta-lactamase (ESBL) producing Klebsiella pneumoniae is a global health problem. This study was aimed to retrospectively evaluate the resistance patterns of K. pneumoniae strains, microbiologically proven as agents of nosocomial bacteremia, between 2001-2005 and also to compare the 2001-2002 and 2004-2005 data to investigate the effect of 2003 budget application on antimicrobial resistance in our country. Data of antimicrobial resistance and hospital admission dates were extracted from the hospital patient record database. 2003 data was excluded to better evaluate the probable effect of governmental antibiotic restriction policy, which was started in March 2003. Blood cultures were performed on Bact/Alert (bioMerieux, Durham, NC) automated system and bacterial identifications were done by conventional methods. Double or more isolates during each episode were counted as one episode. Antibacterial susceptibility testing was done by disc diffusion method according to the recommendations of Clinical Laboratory Standards Institute. Resistance patterns in the 2001-2002 and 2004-2005 periods were compared by chi-square test. No resistance to carbapenems were detected in the strains. The comparison of 2001-2002 and 2004-2005 periods revealed that resistance to amikacin (30% and 19%, respectively), cefuroxime (55% and 37%, respectively), amoxycillin/clavulonate (59% and 46%, respectively), piperacillin/tazobactam (51% and 39%, respectively) and cotrimoxazole (53% and 35%, respectively) were decreased significantly (p < 0.05). The rate of ESBL K. pneumoniae strains was 49% in 2001-2002 period while it decreased to 35% in 2004-2005 period (p < 0.025). The decrease in the resistance rates after the 2003 budget application suggested that this success could be attributed to the evaluation of each patient to be given an extended spectrum antibiotic, by an infectious disease specialist and also more active use of the clinical microbiology laboratory.

A survey of antibiotic resistance in Streptococcus pneumoniae and Haemophilus influenzae in Turkey, 2004 2005.

OBJECTIVES: To determine the prevalence of antimicrobial resistance among Streptococcus pneumoniae and Haemophilus influenzae isolated in Turkey as part of Survey Of Antibiotic Resistance, a surveillance programme in the Africa and Middle East region examining the antimicrobial susceptibility of key bacterial pathogens involved in community-acquired respiratory tract infections (CARTIs). METHODS: Susceptibility was evaluated against a range of antimicrobial agents using disc diffusion and Etest methods. RESULTS: Six centres in five cities collected 301 S. pneumoniae and 379 H. influenzae isolates between October 2004 and November 2005. Among S. pneumoniae, the prevalence of isolates with intermediate susceptibility (MICs 0.12-1 mg/L) and resistance to penicillin (MICs >or=2 mg/L) was 24.6% and 7.6%, respectively; there was a wide variation between cities (2.4% to 36.9% intermediate and 0% to 23.8% resistant phenotypes). Macrolide-azalide resistance rates exceeded those of penicillin resistance in all cities. Overall, 5.0% of isolates were co-resistant to penicillin and erythromycin and 10.0% were multidrug-resistant (joint resistance to erythromycin, co-trimoxazole and tetracycline). Agents tested to which over 90% of countrywide S. pneumoniae isolates remained susceptible were amoxicillin/clavulanate (98.7%), chloramphenicol (94.7%) and cefprozil (90.6%). Overall, the percentage of H. influenzae isolates producing beta-lactamase was 5.5%, differing widely across the country with the highest prevalence of beta-lactamase production detected in Trabzon (14.0%) and no beta-lactamase-positive isolates found in Izmir. H. influenzae had the highest per cent susceptibility to amoxicillin/clavulanate (99.5%) and ofloxacin (99.2%) while >20% were resistant to co-trimoxazole. CONCLUSIONS: Prevalence of penicillin and macrolide-azalide resistance among S. pneumoniae appears to be on the increase in Turkey while overall beta-lactamase production in H. influenzae remains relatively low. To adequately monitor the spread of drug-resistant phenotypes among these two important CARTI pathogens, ongoing collection of resistance surveillance data is required-where possible locally as resistance patterns can vary substantially between cities and institutions.

Short-term effect of antibiotic control policy on the usage patterns and cost of antimicrobials, mortality, nosocomial infection rates and antibacterial resistance.

OBJECTIVES: In 2003 Turkish government released a new budget application instruction for regulating the usage of parenteral antibiotics inside and outside of the hospitals. In this study it was aimed to evaluate the effect of this instruction on the overall usage of restricted antibiotics, their cost, overall mortality, bacterial resistance patterns and nosocomial infection rates in intensive care units (ICUs) of our setting for March-October 2002 and March-October 2003 periods. METHODS AND RESULTS: Overall daily defined dose/1000 patients/day of restricted drugs decreased, whereas unrestricted drugs increased significantly after the instruction. The cost of all analysed drugs in 2003 period was 540,303USD (-19.6%) less than 2002 period. Nosocomial infection rates in ICUs decreased significantly (p<0.05). When all microbiologically confirmed nosocomial bacteremia cases during the study period were analysed, amoxycilline/clavulanate, ciprofloxacin, cefuroxime, cefotaxime, piperacilline/tazobactam resistance and ESBL rate in Klebsiella pneumoniae decreased significantly (p<0.05). Amikacin resistance in Escherichia coli and Acinetobacter baumannii increased significantly (p<0.05). CONCLUSION: Antibiotic control is one of the most important and significant ways to save money, and to prevent antibacterial resistance.

Neonatal nosocomial sepsis in a level-III NICU: evaluation of the causative agents and antimicrobial susceptibilities.

Despite advances in supportive care and use of antibiotics, sepsis preserves its importance due to its high mortality and morbidity for neonates. Identifying the causative agents and antibiotic resistance yearly in a neonatal intensive care unit (NICU) helps the physician to choose the most appropriate empirical therapy. In this study we aimed to evaluate positive blood cultures and antibiotic susceptibilities of newborns with proven sepsis during the years 2000-2002 in our NICU. The charts of babies with sepsis were evaluated for clinical characteristics, positive cultures and antimicrobial susceptibilities, retrospectively. Although most of the admitted patients were premature (76.5%), the frequency of proven sepsis was quite low, at 9.1% among 909 newborns. Mortality rate in sepsis was 16%. The most commonly isolated micro-organisms were coagulase-negative staphylococci (CoNS) (31.3%), fungi (19.2%), Staphylococcus aureus (13%) and Klebsiella pneumoniae (10.5%). Methicillin resistance for CoNS was 92.3% and for S. aureus was 72.7%. In the last year, a significant increase in the frequency of Klebsiella pneumoniae (8.3 vs 14.2%), CoNS (27.1 vs 37.1%), Pseudomonas aeruginosa (2.1 vs 8.6%) and fungal infections (18.8 vs 20%) was observed compared to the previous years. An initial empirical antibiotic therapy for late-onset sepsis was designed with teicoplanin + piperacillin-tazobactam/meropenem + antifungal (fluconazole or amphotericin B) as the best combination to cover this spectrum until the culture results arrive. However, this combination is only compatible with our results and may not be applied in all units. Every unit must follow the bacterial spectrum and antibacterial resistance patterns to choose their specific empirical treatment strategy for nosocomial infections.

In vitro activities of various antimicrobials against Brucella melitensis strains in the Aegean region in Turkey.

OBJECTIVE: To study in vitro activities of three quinolones (ciprofloxacin, levofloxacin, moxifloxacin), four macrolides (erythromycin, dirithromycin, azithromycin, clarithromycin) and doxycycline against 44 clinical isolates of Brucella melitensis. MATERIALS AND METHODS: Forty-four B. melitensis strains were isolated from blood cultures of adult patients with acute brucellosis who were hospitalized in the clinical ward of the Department of Clinical Microbiology and Infectious Diseases. The minimum inhibitory concentrations (MICs) of the tested antimicrobials were measured by the agar dilution method. MIC90 and MIC50 values were defined as the lowest concentration of the antibiotic at which 90 and 50% of the isolates were inhibited, respectively. RESULTS: Doxycycline (MIC50: 0.25 microg/ml, MIC90: 0.50 microg/ml) had the lowest MIC in vitro against the B. melitensis strains. Among the quinolones, ciprofloxacin and levofloxacin had similar activities (MIC50: 0.5 microg/ml, MIC90: 2 microg/ml), whereas MIC of moxifloxacin (MIC50: 1 microg/ml, MIC90: 8 microg/ml) was higher than both antibiotics in this group. Clarithromycin and azithromycin were the most active macrolides (MIC50: 8 microg/ml and MIC90: 32 microg/ml), followed by erythromycin (MIC50: 16 microg/ml, MIC90: 32 microg/ml) and dirithromycin (MIC50: 64 microg/ml and MIC90: 64 microg/ml). CONCLUSION: The results indicate that the conventional agent doxycycline is more active than quinolones and macrolides against the B. melitensis in vitro.

[Bacterial contamination in blood and blood products]. / Kan ve kan urünlerinde bakteriyel kontaminasyon.

Skin disinfection during phlebotomy is a critical step for bacterial contamination of blood and blood products. The aim of this study was to investigate the bacterial contamination rates during phlebotomy and to detect the probable microorganisms present. Skin disinfections of 100 blood donors were performed by using povidone iodine solution with standard procedure. Fifteen mililiters of blood samples were drawn from the transfusion set and inoculated into culture flasks of automated Bact/Alert (BioMerieux) system. Blood cultures were monitorized for one week, and bacteria in positive cultures were identified by using classical microbiological methods in addition with API identification system (BioMerieux; ID32 Staph, 20 Strep). As a result, bacterial growth was detected in four (4%) of the blood samples, whereas 96% of the samples were found sterile. Staphylococcus epidermidis was the microorganism which had been grown in three of the samples, and Streptococcus mutans in one. The positivity rate detected in our study was considered high, since expected bacterial contamination rates in blood transfusions were between 0.2-0.5%. This data indicated that the procedures used in phlebotomy such as the choice of phlebotomy region, disinfectant use and disinfection time should be re-evaluated in our blood centre.

[Salmonella enterica serotypes and Salmonella infections: a multicenter study covering ten provinces in Turkey]. / Salmonella enterica serotipleri ve Salmonella enfeksiyonlari: Türkiye'de on ili kapsayan çok merkezli bir çalisma.

In order to find the distinctive features of Salmonellae and Salmonella infections in Turkey, 620 Salmonellae strains, isolated from various clinical samples (481 stool, 108 blood, 12 urine, 3 bone marrow, 3 cerebrospinal fluid, 9 pus, and one from each of the bile, pleural fluid, wound, catheter samples) in 13 clinical microbiology laboratories of 10 provinces in Turkey (Ankara, Antalya, Bursa, Edirne, Eskisehir, Istanbul, Izmir, Kayseri, Konya and Trabzon) between July 1, 2000 and June 30, 2002, were serotyped. Among the patients 43% were female, 57% were male, 63.2% were from outpatient clinics and 36.8% were hospitalized patients. Seventy eight percent of the patients had gastroenteritis, 10.7% had septicemia/local infection, 9.8% had typhoid/paratyphoid fever and 1.5% were carriers. Incidence of gastroenteritis was higher in 0-5 years age group (p<0.001). Of the 620 Salmonella enterica isolates, 47.7% were S. Enteritidis, 34.7% S. Typhimurium, 6% S. Paratyphi B, 2.9% S. Typhi, 0.2% S. paratyphi A, 6.1% serogroup C1, and 2.4% serogroup C2. S. Enteritidis was the most common serotype in all provinces except for Kayseri, where S. Typhimurium was found to be the most common serotype (68.2%). Overall, the most frequently isolated serotype was S. Enteritidis, also being the most common serotype in stool and blood cultures. During the surveillance period two outbreaks have occurred, the first one by S. Enteritidis strains in Edirne, and the second one by S. Typhimurium strains in Kayseri. As a result, Salmonella infections are still a common health problem in Turkey, and active surveillance of Salmonella infections has vital importance.