Continuous blood culture systems that detect changes in headspace pressure in bottles are referred to as

Continuous blood culture systems that detect changes in headspace pressure in bottles are referred to as

• A. Fluorescence methods
• B. 14C detection methods
• C. Colorimetry methods
• D. Manometric methods

Answer: (D)

Manometric detection relies on measuring gas pressure changes in the bottle’s headspace as microorganisms metabolize and produce CO2 and other gases. In a sealed blood culture bottle, this gas buildup increases the internal pressure, and a pressure sensor or manometer continuously monitors this change. When the pressure rises beyond a set threshold, the system signals a positive culture, allowing rapid notification and handling. This approach differs from radiometric methods that track CO2 via radioactivity, or colorimetric/fluorescence methods that infer growth from changes in sensor optics or pH indicators; those do not directly measure headspace pressure.

Manometric detection relies on measuring gas pressure changes in the bottle’s headspace as microorganisms metabolize and produce CO2 and other gases. In a sealed blood culture bottle, this gas buildup increases the internal pressure, and a pressure sensor or manometer continuously monitors this change. When the pressure rises beyond a set threshold, the system signals a positive culture, allowing rapid notification and handling. This approach differs from radiometric methods that track CO2 via radioactivity, or colorimetric/fluorescence methods that infer growth from changes in sensor optics or pH indicators; those do not directly measure headspace pressure.