İmmünkompromize hastalarda görülen bakteriyemilerden izole edilen etkenler ve antibiyotik duyarlılık profilleri

Bakteriyemi immünkompromize hastalarda önde gelen morbidite ve mortalite nedenidir. Çalışmamızda Başkent Üniversitesi Tıp Fakültesi Ankara Hastanesi’nde 1 Ocak 2012 ve 30 Temmuz 2013 tarihleri arasında izlenen immünkompromize hastalarda gelişen bakteriyemiler, etken dağılımı ve antibiyotik duyarlılık oranlarının belirlenmesi amaçlanmıştır. Başkent Üniversitesi Tıp Fakültesi Ankara Hastanesi Mikrobiyoloji Laboratuvarı’nda BACTEC 9240 (Becton Dickinson) otomatize kan kültürü sistemi ile kan kültüründe “anlamlı” üreme saptanan hastalardan immünkompromize olanlar çalışmaya dahil edildi. Bu çalışmada immünkompromize olarak tanımlanan hasta grubunu, solid organ nakil hastaları (böbrek-karaciğer) ve bakteriyemiden önceki bir ay içinde kemoterapi almış malignite hastaları (hematoloji-onkoloji) oluşturdu. Her bakteriyemi atağı, hastanın demografik verileri, laboratuvar sonuçları, bakteriyemi türü ve kaynağı, etken bakteri ve antibiyotik duyarlılıkları açısından bir forma kaydedildi. Bakteriyemiler kaynağına göre ve ortaya çıkış şekline göre iki farklı şekilde sınıflandırıldı. Kaynağına göre yapılan sınıflamada bakteriyemiler öncelikle primer ve sekonder olmak üzere ikiye ayrıldı. Primer bakteriyemiler ise kendi içinde kateter ilişkili ve kateter ilişkisiz olmak üzere ikiye ayrıldı. Ortaya çıkış şekline göre bakteriyemiler ilk bakteriyemi, konkomitant, persistan ve polimikrobiyal olarak gruplandırıldı. Bakteriyemiler immünkompromize hasta grupları dikkate alınarak karşılaştırıldı. İstatistiksel analiz için SPSS 11 programı kullanıldı, istatistiksel anlamlılık düzeyi p˂0.05 olarak kabul edildi. Bu prospektif çalışma 130 immünkompromize hastada görülen 167 bakteriyemi atağından oluştu. Hastaların 76’sı (%58.4) kadın, 54’ü (%41.6) erkek idi. Yaş ortalaması 58.5 ± 15.17 olarak saptandı. Atakların 49’u (%29.3) nakil hastalarında, 118’i (%70.7) malignite hastalarında görüldü. Yirmidokuz hastada birden fazla bakteriyemi görüldü. Yüzaltmışyedi bakteriyemi atağının dağılımı, 145 (%86.8) ilk bakteriyemi, 9 (%5.4) konkomitant, 8 (%4.8) persistan ve 5 (%3) polimikrobiyal şeklindeydi. Kaynağa göre yapılan sınıflamada 87 primer bakteriyemi (%30 kateter ilişkili, %70 kateter ilişkisiz) ve 80 sekonder bakteriyemi saptandı. Primer kateter ilişkisiz bakteriyemiler hematolojik malignite hastalarında en sık görülen bakteriyemi türü iken diğer immünsupresyon gruplarının hepsinde (böbrek-karaciğer nakil, onkolojik malignite) en sık görülen tür sekonder bakteriyemi idi (p=0.016). Gram negatif bakteriler sekonder bakteriyemilerde primer bakteriyemilerden daha sık görüldü (p=0.000) ayrıca hem nakil hem malignite hasta grubunda en sık görülen etkenler gram negatif ajanlardı. Çalışmada en sık izole edilen bakteri E.coli (%46.1) idi. E.coli suşlarındaki GSBL pozitifliği %51 idi. İkinci en sık gram negatif etken olan Acinetobacter baumannii suşlarında XDR oranı %73 idi. Çalışmanın sonunda gram negatif bakterilerin hastanemizde immünkompromize hastalarda görülen bakteriyemilerde en sık izole edilen etkenler olduğu saptanmıştır. Tedavisi zor enfeksiyonlara yol açan XDR A.baumannii suşlarının artan sıklığı da dikkat çekicidir. Bacteremia is the leading cause of morbidity and mortality among immunocompromised patients. The aim of this study is to evaluate the etiology of bacteremia and the antibiotic susceptibilities of etiologic agents among immunocompromised patients followed up at Baskent University Ankara Hospital from January 1st 2012 to July 30th 2013. The immunocompromised patients who had ‘significant’ positive blood cultures which were isolated by automatic blood culture system BACTEC 9240 (Becton Dickinson) at the Microbiology Laboratuary of Başkent University Ankara Hospital were included in the study. The definition of “immunocompromised patients” consisted of solid organ transplant recipients (kidney, liver) and hemato-oncologic malignancy patients with a history of chemotherapy in the last month before bacteremia. Each bacteremia episode was recorded on a form regarding the patient’s demographic data, laboratuary results, kind of bacteremia, source of bacteremia, name and antibiotic susceptibility of bacteria. Two classifications were used for bacteremias. First classification was made according to source of bacteremia: as primary and secondary bacteremia. Primary bacteremias were divided into two groups; as catheter-related and catheter-unrelated. Second classification was made according to occurence of bacteremia; first bacteremia episode, concomitant, persistant and polymicrobial. The etiologic agents of bacteremia episodes were compared regarding the immunocompromised patient groups. SPSS version 11.0 was used for statistical analysis and p<0.05 was considered to be statistically significant. This prospective study comprised of 167 bacteremia episodes in 130 consecutive immunocompromised patients. Seventysix (58.4%) patients were female and fiftyfour (41.6%) patients were male. The mean age of patients was 58.5 ± 15.17. Fourty-nine of the episodes (29.3%) were seen in solid organ recipients and 118 episodes (70.7%) were seen in patients with malignancy. Twenty-nine patients had more than one bacteremia episodes. The distribution of 167 bacteremia episodes were: 145 (86.8%) first bacteremia episode, 9 (5.4%) concomitant, 8 (4.8%) persistant, 5 (3%) polymicrobial bacteremia. There were 87 primary (30:cathether-related, 70:cathether-unrelated) and 80 secondary bacteremias according to the source of bacteremias. The primary catheter-unrelated bacteremia was the most common type of bacteremia in patients with hematological malignancy but in all of the other immunsupressive groups (renal-liver transplantation, solid organ malignancy) secondary bacteremia was the most common type of bacteremia (p=0.016). Gram negative microorganisms were more commonly seen in secondary bacteremia episodes than primary bacteremia episodes (p=0.000). Also gram negative bacteria were the most common agents in both transplant and malignancy groups. E.coli was the most commonly isolated (46.1%) bacteria in this study. Fiftyone percent of the E.coli isolates were ESBL positive. Acinetobacter baumannii was the second most common gram negative agent and the ratio of XDR isolates among Acinetobacter isolates was 73%. Gram negative bacteria are the most common causative agents of bacteremia in immunocompromised patients in our hospital. The rising ratio of XDR A.baumannii is a striking problem which causes difficult-to-treat infections

The Distribution and Antimicrobial Susceptibility Profiles of Etiologic Agents Isolated From Bacteremia Episodes Among Immunocompromised Patients

Objective: Bacteremia is the leading cause of morbidity and mortality among immunocompromised patients. The aim of this study is to evaluate the etiology of bacteremia and the antibiotic susceptibilities of etiologic agents among immunocompromised patients followed up from January 1, 2012 to July 30, 2013. Methods: Immunocompromised patients, both inpatient and outpatient treated in our hospital, were followed prospectively. The definition of "immunocompromised patients" consisted of solid organ (kidney, liver) transplantation recipients and hemato-oncologic malignancy patients with a history of chemotherapy in the previous month before bacteremia. Results: This prospective study comprised of 167 bacteremia episodes of 130 consecutive immunocompromised patients. The most isolated group of bacteria was Gram-negative bacteria. Escherichia coli was the most commonly (30.8%) isolated bacteria and the second was coagulase-negative staphylococci (15.1%). Fifty one percent of the E. coli isolates were extended-spectrum beta-lactamasepositive. Acinetobacter baumannii was the second most common bacteria of Gram-negative agents and the ratio of multiple drug-resistant (MDR) isolates among Acinetobacter isolates was 73%. Conclusions: Gram-negative bacteria are the most common causative agents of bacteremia in immunocompromised patients in our hospital. The rising ratio of MDR A. baumannii is a striking problem which causes difficult-to-treat infections

Bloodstream Infections among Solid Organ Transplant Recipients: Eight Years’ Experience from a Turkish University Hospital

Background: Bloodstream infections (BSI) are frequently seen after solid organ transplantation. The incidence of bloodstream infections differs among the types of transplantation. The microbiological features and antimicrobial resistance patterns change from centre to centre. Aims: To evaluate the incidence and spectrum of aetiological agents of bloodstream infections among solid organ transplantation recipients. Study Design: Retrospective descriptive study. Methods: Medical records of solid organ transplant recipients in the period between January 1st 2004 and August 15th 2012 were assessed retrospectively. The study population comprised 927 (64 heart, 556 kidney, 307 liver) consecutive recipients. Bloodstream infections were divided into three groups according to the onset time of bloodstream infections after transplantation: early, mid-term and late. The incidence and microbiological features of bloodstream infections were evaluated. Results: The number of bloodstream infection episodes was 317 in 191 recipients which was distributed as 228 (72%) in liver, 70 (22%) in kidney and 19 (6%) in heart transplantation. Ninety-eight 98 (30.9%) of the episodes were diagnosed within the early period, 134 (42.3%) within the mid-term and 85 (26.8%) in the late period. Early and mid-term bloodstream infections were seen statistically more often in liver than in kidney or heart transplantation (p=0.01 and p=0.031, respectively). Late bloodstream infections were also common in liver transplant recipients which was not statistically significant (p=0.229). Conclusion: Liver transplant recipients are at the highest risk for developing BSI after transplantation in early, mid-term and late periods

Changes in antimicrobial resistance and outcomes of health care-associated infections

To describe the change in the epidemiology of health care-associated infections (HAI), resistance and predictors of fatality we conducted a nationwide study in 24 hospitals between 2015 and 2018. The 30-day fatality rate was 22% in 2015 and increased to 25% in 2018. In BSI, a significant increasing trend was observed for Candida and Enterococcus. The highest rate of 30-day fatality was detected among the patients with pneumonia (32%). In pneumonia, Pseudomonas infections increased in 2018. Colistin resistance increased and significantly associated with 30-day fatality in Pseudomonas infections. Among S. aureus methicillin, resistance increased from 31 to 41%