Comparison of Blood Culture and Multiplex PCR Results in Patients Prediagnosed with Sepsis

Öz

Aim: Sepsis is a life-threatening infection that affects multiple systems, leading to hemodynamic changes, shock, organ dysfunction, and potentially organ failure. Although blood culture is the gold standard for identifying the causative agent, the pathogen cannot be isolated in some cases, posing significant challenges in diagnosis and treatment, affecting mortality and morbidity rates. The aim of this study is to retrospectively and prospectively evaluate the results of blood cultures and the Multiplex PCR sepsis panel sent to Microbiology laboratory. Material and Method: In this study, 100 samples sent to our laboratory for blood culture and sepsis panel between September 1, 2023, and August 31, 2024, were analyzed retrospectively and prospectively. All bottles with a positive signal were subjected to Gram staining, and simultaneous inoculations were made on 5% sheep blood agar, EMB, SDA, and Chocolate agar. After 24–48 hours of incubation at 37°C, the isolated strains were identified using conventional methods (colony morphology, Gram staining, etc.) and biochemical tests (catalase test, oxidase test, tube and slide coagulase tests). For the sepsis panel, nucleic acid extraction was performed on samples received in the laboratory using a total nucleic acid extraction kit based on magnetic bead technology, following the manufacturer’s instructions. Results: According to the PCR results of the 100 blood samples included in the study, Candida species were detected in 4 samples. Candida species were also identified in the blood culture. The distribution of strains in the sepsis panel included C.tropicalis, C.albicans, C.glabrata, and C.krusei. Among the blood culture samples, three demonstrated results that were consistent with the sepsis panel findings, while one sample was identified as C.glabrata through conventional methods, in contrast to the result from the sepsis panel. Among bacterial pathogens, Staphylococcus spp. was the most frequently identified (56 cases), followed by Escherichia coli. Conclusion: The results of this study demonstrate that PCR is an effective method for diagnosing sepsis; however, some results need to be confirmed by blood culture. PCR testing provides rapid and accurate information, particularly in situations where quick results are essential, such as in intensive care units and emergency departments. However, it should be noted that PCR can amplify DNA from dead bacteria, so results should be interpreted with caution. In clinical practice, the combined use of both tests will contribute to more effective patient management and treatment.

Anahtar Kelimeler

• sepsis
• blood culture
• multiplex PCR

Kaynakça

1. 1. Özdemir YE, Aygün G. Sepsis Tanısı İçin Moleküler Yöntemlerdeki Yenilikler. Klimik Dergisi. 2024;37(2):76–82.
2. 2. Li Y, Ma M, Xu X, Li Q, Ji C. Value of digital PCR in the early diagnosis of sepsis: A systematic review and meta-analysis. Journal of Critical Care. 2022;72:154138.
3. 3. Jiang S, Zhao D, Wang C, Liu X, Yang Q, Bao X, et al. Clinical evaluation of droplet digital PCR in the early identification of suspected sepsis patients in the emergency department: a prospective observational study. Frontiers in Cellular and Infection Microbiology. 2024;14:1358801.
4. 4. Balıkçı A, Belas Z, Topkaya AE. Kan kültürü pozitifliği: etken ya da kontaminasyon mu? Mikrobiyol Bul. 2013;47(1):135–40.
5. 5. Gülhan B, Atmaca S, Özekinci T, Suay A. Kan Kültürlerinde Üreyen Gram-Pozitif Kokların Tanımlanması ve mecA ve van Genlerinin Saptanmasında Hızlı Genotip Testinin Değerlendirilmesi. Mikrobiyol Bul. 2011;45(4):592–601.
6. 6. Ünal Eşiyok A. Sepsis tanısında moleküler yöntemlerin konvansiyonel yöntemler ile karşılaştırılması. Adnan Menderes Üniversitesi Tıp Fakültesi. Uzmanlık tezi. 2016.
7. 7. Çolakoğlu Ş, Coşar Bulat M, Turunç T. Sepsis Şüphesi Olan Hastalarda LightCycler® Septifast Testinin Tanı Değeri. Turk Mikrobiol Cem Derg. 2015;45(2):75–82.
8. 8. Westh H, Lisby G, Breysse F, Böddinghaus B, Chomarat M, Gant V, et al. Multiplex real-time PCR and blood culture for identification of bloodstream pathogens in patients with suspected sepsis. Clinical Microbiology and Infection. 2009;15(6):544–51.

9. 9. Dinc F, Akalin H, Özakin C, Sinirtaş M, Kebabci N, Işçimen R, et al. Comparison of blood culture and multiplex real-time PCR for the diagnosis of nosocomial sepsis. Minerva anestesiologica. 2016;82(3):301–9.
10. 10. Bloos F, Hinder F, Becker K, Sachse S, Mekontso Dessap A, Straube E, et al. A multicenter trial to compare blood culture with polymerase chain reaction in severe human sepsis. Intensive care medicine. 2010;36:241–7.
11. 11. Dierkes C, Ehrenstein B, Siebig S, Linde H-J, Reischl U, Salzberger B. Clinical impact of a commercially available multiplex PCR system for rapid detection of pathogens in patients with presumed sepsis. BMC infectious diseases. 2009;9:1–7.
12. 12. Lucignano B, Ranno S, Liesenfeld O, Pizzorno B, Putignani L, Bernaschi P, et al. Multiplex PCR allows rapid and accurate diagnosis of bloodstream infections in newborns and children with suspected sepsis. Journal of clinical microbiology. 2011;49(6):2252–8.
13. 13. Kesmen Z, Aslan H. Determination of Viable Salmonella Typhimurium Cells in Heat Treated Milk By PMA/Real-Time PCR Method. Turkish Journal of Agriculture. 2017;5(5):51824.
14. 14. Mancini N, Clerici D, Diotti R, Perotti M, Ghidoli N, De Marco D, et al. Molecular diagnosis of sepsis in neutropenic patients with haematological malignancies. Journal of medical microbiology. 2008;57(5):601–4.
15. 15. Avolio M, Diamante P, Zamparo S, Modolo ML, Grosso S, Zigante P, et al. Molecular identification of bloodstream pathogens in patients presenting to the emergency department with suspected sepsis. Shock. 2010;34(1):27–30.
16. 16. Wisplinghoff H, Bischoff T, Tallent SM, Seifert H, Wenzel RP, Edmond MB. Nosocomial bloodstream infections in US hospitals: analysis of 24, 179 cases from a prospective nationwide surveillance study. Clinical infectious diseases. 2004;39(3):309–17.
17. 17. Yertut B. Sepsis tanısında yeni moleküler yöntemlerin kullanılması. Gaziantep Üniversitesi Sağlık Bilimleri Enstitüsü. 2012.
18. 18. Trick W, Fridkin S, Edwards J, Hajjeh R, Gaynes RP, Hospitals NNISS. Secular trend of hospital-acquired candidemia among intensive care unit patients in the United States during 19891999. Clinical infectious diseases. 2002;35(5):627–30.
19. 19. Doğanay M, Alp Meşe EB. In Wilke Topçu A, Söyletir G, Doğanay M, editors. İnfeksiyon Hastalıkları ve Mikrobiyolojisi İstanbul: Nobel Tıp Kitapevleri. 2008:897–909. 20. Duman Y, Kuzucu Ç, Çuğlan SS. Kan kültürlerinden izole edilen bakteriler ve antimikrobiyal duyarlılıkları. Erciyes Tıp Dergisi. 2011;33(3):189–96.
20. 21. Mehli M, Gayyurhan ED, Zer Y, Akgün S, Akın FEÖ, Balcı İ. Gaziantep Üniversitesi Tıp Fakültesi Hastanesi’nde Kan Kültürlerinden İzole Edilen Mikro-Organizmalar Ve Antibiyotik Duyarlılıkları. İnfeksiyon Dergisi. 2007;21(3):141–5.
21. 22. Yüce P, Demidağ K, Kalkan A, Özden M, Denk A, Kılıç SS. Kan Kültürlerinden izole Edilen Mikroorganizmalar ve Antibiyotik Duyarlılıkları. Ankem Derg. 2005;19(1):17–21.
22. 23. Li Y, Ma M, Xu X, Li Q, Ji C. Value of digital PCR in the early diagnosis of sepsis: A systematic review and meta-analysis. J Crit Care. 2022;72:154138.
23. 24. Zhao Z, Wang Y, Kang Y, Wu G, He J, Wang Z, et al. A retrospective study of the detection of sepsis pathogens comparing blood culture and culture-independent digital PCR. Heliyon. 2024;10(6):e27523.