IMMATURE GRANULOCYTES; CAN IT SEPARATE TRUE BACTERIA FROM CONTAMINATION?

Öz

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.

Anahtar Kelimeler

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

İMMATÜR GRANÜLOSİTLER; GERÇEK BAKTERİYEMİYİ KONTAMİNASYONDAN AYIRABİLİR Mİ?

Öz

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. 

Anahtar Kelimeler

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

Kaynakça

1. 1. García-Vázquez E, Fernández-Rufete A, Hernández-Torres A et al. When is coagulase-negative Staphylococcus bacteraemia clinically signifi cant? Scandinavian Journal of Infectious Diseases 2013; 45: 664–671.
2. 2. Morioka S, Ichikawa M, Mori K et al. Coagulase-negative staphylococcal bacteraemia in cancer patients. Infect Dis 2018; 50: 660-665.
3. 3. L. Elzi, B. Babouee, Vögeli N et al. How to discriminate contamination from bloodstream infection due tocoagulase-negative staphylococci: a prospective study with 654 patients. Clinical Microbiology and Infection.2012; 18: 9.
4. 4. Al Wohoush I, Rivera J, Cairo J, et al. Comparing clinical and microbiological methods for the diagnosis of true bacteraemia among patients with multiple blood cultures positive for coagulase-negative staphlococci. Clin Microbiol Infect 2011; 17: 569-571
5. 5. R. Krause, R. Haberl, A. Wölfler, et al. Molecular typing of Coagulase-Negative Staphylococcal Blood and Skin Culture Isolates to Differentiate Between Bacteremia and Contamination. Eur J Clin Microbiol Infect Dis 2003; 22: 760–763.
6. 6. Senthilnayagam B, Kumar T, Sukumaran J, et al. Automated measurement of immature granulocytes: performance characteristics and utility in routine clinical practice. Pathol Res Int 2012; 2012: 483670. doi: 10.1155/2012/483670.
7. 7. Park JH, Byeon HJ, Lee KH, et al. Delta neutrophil index (DNI) as a novel diagnostic and prognostic marker of infection: a systematic review and meta-analysis. Inflamm Res 2017; 66: 863–870.
8. 8. Ayres LS, Sgnaolin V, Munhoz TP. Immature granulocytes index as early marker of sepsis. Int J Lab Hematol 2019; 41(3): 392-396.

9. 9. Shin DH, Cho YS, Cho GC, et al. Delta neutrophil index as an early predictor of acute appendicitis and acute complicated appendicitis in adults. World J Emerg Surg 2017; 12: 32.
10. 10. Jong Wan Kim, Jun Ho Park, Doo Jin Kim, et al. The delta neutrophil index is a prognostic factor for postoperative mortality in patients with sepsis caused by peritonitis. PLoS ONE 2017; 12(8): e0182325.
11. 11. Ha SO, Park SH, Park SH et al. Fraction of immature granulocytes refrects severity but not mortality in sepsis. Scand J Clin Lab Invest 2015; 75(1): 36-43.
12. 12. Cha YS, Lee KH, Lee JW, et al. The use of delta neutrophil index and myeloperoxidase index as diagnostic predictors of strangulated mechanical bowel obstruction in the emergency department. Medicine 2016; 95: 48.
13. 13. Ünal Y. A new and early marker in the diagnosis of acute complicated appendicitis: immature granulocytes. Ulus Travma Acil Cerrahi Derg 2018; 24: 434-439.
14. 14. Lee SM, Eun HS, Namgung R, et al. Usefulness of the delta neutrophil index for assessing neonatal sepsis. Acta Paediatr 2013; 102: 13-16.
15. 15. Seok Y, Choi JR, Kim J, et al. Delta neutrophil index: a promising diagnostic and prognostic marker for sepsis. Shock 2012; 37: 242-246.
16. 16. Park BH, Kang YA, Park MS, et al. Delta neutrophil index as an early marker of disease severity in critically ill patients with sepsis. BMC Infect Dis 2011; 11: 299.
17. 17. Lee CH, Jim K, Park Y, et al. Delta neutrophil index discriminates true bacteremia from blood culture contamination. Clinica Chimica Acta 2014; 427: 11-14.
18. 18. Sarıkaya ZT, Akıncı Ö. Persistant İnflamasyon, İmmunsupresyon ve Katabolizma Sendromu (PİCS). Turk J Intensive Care 2019; DOI:10.4274/tybd.galenos.2019.19484.