Outbreak of Healthcare-Associated Infections Outbreak Tied to Contaminated Ultrasound Gel

After a 2011 outbreak of Psduomonas aeruginosa, investigators determined contaminated ultrasound gel was the source of bacteria causing the healthcare-associated infection. These new findings emphasize the need for increased scrutiny of contaminated medical products.

This study’s findings were published in the August 2013 issue of Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America. “Ultrasound is a critical healthcare tool used every day in both diagnostic and interventional procedures,” said Paul Chittick, MD, from the Beaumont Health System (Royal Oak, MI, USA), and lead author of the study. “Although contaminated gel has been the cause of several documented outbreaks of infection, its potential role as a vehicle for spreading infections to patients is frequently overlooked.”

Investigators, in December 2011, discovered a unique cluster of P. aeruginosa in the cardiovascular surgery intensive care unit during routine infection control surveillance. The bacteria are known to increase the risk of bloodstream and respiratory infections in immune-compromised individuals. Sixteen patients became colonized or infected with the bacteria, with all cases occurring in the respiratory tract. The outbreak was discovered to have come from bottles of ultrasound transmission gel used during cardiovascular surgery. Following replacement of this gel with a sterile product, no additional cases occurred.

Cultures of gel from a bottle in use in the operating room grew P. aeruginosa that was identical to the outbreak strain. It was initially believed that the gel had probably become contaminated during use. However, sealed bottles of gel grew the same P. aeruginosa strain, proving that the product was contaminated during the manufacturing process at the plant of Pharmaceutical Innovations (Newark, NJ, USA).

As a result of this investigation, the US Food and Drug Administration (FDA) issued a warning about the gel, warming about the risk of infection posed by the product and instructing healthcare providers and systems not to use the infected products.

The Beaumont Health System investigators also recently published proposed guidelines in Infection Control and Hospital Epidemiology for the use of sterile versus nonsterile ultrasound gel. These guidelines include the need for sterile, single-dose ultrasound gel to be used for all invasive procedures and give appropriate storage and warming methods for the gel. Before this, no such guidelines existed in the United States.

Related Links:

Beaumont Health System