Improved blood culture technique based on centrifugation: clinical evaluation

Area of Science:

• Medical Microbiology
• Clinical Diagnostics
• Infectious Diseases

Background:

• Bacteremia diagnosis relies on effective blood culture methods.
• Traditional broth methods have limitations in sensitivity and speed.
• Optimizing blood culture techniques is crucial for patient outcomes.

Purpose of the Study:

• To compare the efficacy of lysis centrifugation versus supplemented peptone broth for bacteremia detection.
• To evaluate the speed of detection and contamination rates for both methods.
• To assess the utility of quantitative data from lysis centrifugation.

Main Methods:

• Analysis of 3,335 blood samples from 1,180 patients using two concurrent methods.
• Method 1: Supplemented peptone broth with sodium polyanethanol sulfonate and CO2.
• Method 2: Lysis centrifugation at 3,000 x g for 30 min onto a hydrophobic cushion.

Main Results:

• Lysis centrifugation recovered 80% of positive cultures, compared to 67% for broth.
• Faster detection times were observed with lysis centrifugation.
• Increased isolation of Staphylococcus aureus, Pseudomonas, and yeasts was noted with centrifugation.
• Comparable contamination rates (1.4%) for both methods.
• Quantitative data from centrifugation aided in differentiating infections and assessing therapy.

Conclusions:

• Lysis centrifugation is a more sensitive and rapid method for detecting bacteremia.
• The quantitative aspect of lysis centrifugation provides additional diagnostic value.
• This technique enhances the diagnosis and management of bloodstream infections.