The Problem with False-Positive Blood Cultures

"Blood cultures may be one of the worst tests in all of microbiology."

– Chris Doern, PhD, D(ABMM), Director of Clinical Microbiology, VCU School of Medicine

Blood culture collection is a flawed process...

 

Blood cultures are considered the ‘gold standard’ for diagnosing bloodstream infections, such as sepsis. The problem is that roughly 40% of positive blood cultures are false positive due to blood culture contamination.4 These unreliable test results fail to provide clear direction to clinicians responsible for setting the appropriate treatment pathway for their patients. View this video to learn more.

How does it happen?

Common sources of blood culture contamination

Contamination - Human Factors
Human Factors

Risk of touch-point contamination during assembly of supplies, skin prep and waste tube handling

Contamination - Skin
Skin Flora (microorganisms)

Up to 20% of skin flora remains viable in the keratin layer of the skin even after skin prep¹

Contamination - Plugs
Skin Plugs & Fragments

Can enter the culture specimen bottle and will commonly contain viable microorganisms

Million
Americans impacted by false-positive blood cultures every year

Current 'Standards'

Blood culture contamination is not a new problem- it has been plaguing the healthcare system for decades. The national benchmark for blood culture contamination is 3% in the US.² While that may sound small, the number of patients at risk to the harmful consequences of unnecessary treatment adds up quickly.

Concerned Doctor
Downstream Consequences

Why should you care about false-positive blood cultures?

They can lead to patient harm.

False-positive blood culture results often lead to a misdiagnosis of sepsis. Misdiagnosed patients receive unnecessary broad spectrum antibiotic treatment and can have their length of stay extended by several days. As a result, they are exposed to risks of secondary infections, such as C. diff, MDROs, other antibiotic-associated complications and increased exposure to HAC/HAIs.5

They contribute to antibiotic resistance.

Due to the life threatening nature of bloodstream infections, most sepsis protocols require immediate broad-spectrum antibiotics. Therapy can be de-escalated for patients with a negative blood culture, but typically continued with positive or false-positive blood culture results. In false-positive test instances, these unnecessary antibiotics contribute to the global antibiotic resistance crisis.

They can be expensive.

Every false-positive blood culture results in an additional $4,739 in hospital costs on average.³ With 1.2 million patients impacted by a false-positive blood culture in the United States each year, this equals over $5 billion in unnecessary hospital costs.

They impact the entire hospital.

  • Emergency Department
  • Nursing / Phlebotomy
  • Laboratory
  • Infection Prevention
  • Antimicrobial Stewardship
  • Sepsis Management
  • Quality Outcome Metrics
  • Finance

Make an impact at your hospital by reducing blood culture contamination

Continue Reading
The Challenge

What differentiates Steripath Gen2 from other techniques and methods

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Steripath Gen2

Blood culture collection & contamination prevention system

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The Benefits

The clinical & economic impact of reducing blood culture contamination

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The Evidence

Explore the independent clinical study results using Steripath

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REFERENCES

1) Anjanappa T. H, Arjun A. ”Preparative Skin Preparation and Surgical Wound Infection”. Journal of Evidence based Medicine and Healthcare; Volume 2, Issue 2, January 12, 2015; Page: 131-154
2) Richard G. Patton Blood Culture Contamination Definitions Can Obscure the Extent of Blood Culture Contamination: A New Standard for Satisfactory Institution Performance Is Needed. Infection Control & Hospital Epidemiology, Available on CJO 2016 doi:10.1017/ice.2016.30
3) Skoglund, E., et al. (2018). Estimated clinical and economic impact through use of a novel blood collection device to reduce blood culture contamination in the emergency department: A cost-benefit analysis. J. Clin. Microbiol, Online.
4) Zwang o. Albert RK. Analysis of Strategies to Improve Cost Effectiveness of Blood Cultures. J Hosp Med. 2006 Sep:1(5):272-6.
5) Robert Garcia, et al., American Journal of Infection Control, 2017.