Diagnostic Performance of Droplet Digital PCR for Detecting Pathogens and Resistance Genes in Patients with Suspected Bloodstream Infections

Purpose: We aimed to evaluate the diagnostic performance and clinical impact of droplet digital PCR (ddPCR) in patients with suspected bloodstream infections (BSIs) and demonstrated how ddPCR can benefit diagnostic and antimicrobial stewardship efforts. Patients and Methods: We conducted a prospective study in a tertiary hospital in China, 50 patients with suspected BSIs were recruited and 50 blood samples were collected for ddPCR and blood culture (BC). Results: In terms of diagnostic performance, ddPCR exhibited a superior detection rate (64% vs 30%), a relatively high sensitivity (86.67%), and less turn-around time (27.16 ± 13.95 hours vs 70.87 ± 15.8 hours, P < 0.0001) compared to BC. The presence of bla KPC and Klebsiella pneumoniae was detected by ddPCR and later confirmed by BC in three patients. Based on the rapid ddPCR results, the antimicrobial therapy was adjusted to ceftazidime/avibactam (2.5 g q8h) to target the pathogen. This case showed that ddPCR could reduce the time to diagnosis and promotes precise antibiotic use. Conclusion: The clinical value of ddPCR is to detect and quantify pathogens and resistance genes early to provide appropriate guidance for therapeutic options. Keywords: droplet digital PCR, antibiotic resistance genes, clinical application, carbapenem resistance