IMMATURE GRANULOCYTES; CAN IT SEPARATE TRUE BACTERIA FROM CONTAMINATION?

Abstract

Immature granulocyte (IG) has been reported to be useful in the diagnosis of sepsis and in distinguishing true bacteremia from contamination. In this study, we aimed to evaluate the role of IG level in distinguishing true bacteremia and contamination from Coagulase Negative Staphylococci (CNS) and to compare IG value with previously accepted markers such as WBC (White Blood Cell), procalcitonin (PCT) and C-reactive protein (CRP). The blood culture CNS positive group was divided into true bacteremia (n = 71, Group I) and contamination (n = 66, Group II). Blood cultures were incubated in the BacT-ALERT 3D Microbial Identification System (BioMérieux, France). Blood culture vials giving positive (reproduction) signals in the device were passaged to appropriate media. Staphylococcal colonies grown on the media were evaluated by Gram staining, catalase, and coagulase tests. Whole blood cell count data were obtained from the Automatic Hematological Auto analyzer (Sysmex XN 3000). We found IG concentration higher in the group with true CNS bacteremia compared to the contamination group, but this elevation was not statistically significant. In addition, WBC, PCT, and CRP values were higher in CNS bacteremia, but WBC and PCT were statistically significant, whereas CRP was not significant. Due to the limitations stated in our study, IG values indicate that there is no discriminating power for CNS with true bacteremia and contamination. In the future, this comparison should be confirmed by a prospective study, taking into account the existing limitations.

Keywords

• Bacteremia
• C-reactive protein
• contamination
• immature granulocyte
• procalcitonin.

İMMATÜR GRANÜLOSİTLER; GERÇEK BAKTERİYEMİYİ KONTAMİNASYONDAN AYIRABİLİR Mİ?

Abstract

Immatür granülosit (IG) sepsis tanısında ve gerçek bakteri yeminin kontaminasyondan ayırımında yararlı olduğu bildirilmiştir. Bu çalışmada, Koagülaz Negatif Stafilokok (KNS) için gerçek bakteriyemi ile kontaminasyon ayırt edilmesinde IG düzeyinin rolünü değerlendirmeyi ve IG değerini WBC (White Blood Cell), prokalsitonin (PCT) ve C-reaktif protein (CRP) gibi daha önce kabul görmüş belirteçler ile karşılaştırmayı amaçladık. Kan kültürü KNS pozitif grubu gerçek bakteriyemi (n = 71, Grup I) ve kontaminasyon (n = 66, Grup II) olarak ayrıldı. Kan kültürleri BacT-ALERT 3D Mikrobiyal İdentifikasyon Sistemi (BioMérieux, France)’inde inkübe edildi. Cihazda pozitif (üreme) sinyali veren kan kültürü şişeleri uygun besiyerlerine pasajlandı. Besiyerlerinde üreyen stafilokok görünümlü koloniler, Gram boyama, katalaz ve koagulaz testleri ile değerlendirildi. Tam kan hücresi sayımı verileri, Otomatik Hematolojik Otoanalizör (Sysmex XN 3000 )'den elde edildi. IG konsantrasyonlarını kontaminasyon grubuna kıyasla gerçek KNS bakteriyemisi olan grupta daha yüksek bulduk ancak bu yükseklik istatistiksel olarak anlamlı değildi. Ayrıca WBC, PCT ve CRP değerleri de KNS bakteriyemisinde daha yüksekti ancak WBC ve PCT’deki yükseklik istatistiksel olarak anlamlı iken CRP’deki yükseklik anlamsızdı.Çalışmamızda belirtilen kısıtlılıklar nedeniyle IG değerlerinin KNS için gerçek bakteriyemi ile kontaminasyonu ayırt edici gücü olmadığına işaret etmektedir. 

Keywords

• İmmatür granülosit
• bakteriyemi
• kontaminasyon
• prokalsitonin
• C-reaktif protein

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