Outbreaks and deaths caused by infections from ultrasound procedures In recent years, ultrasound use has proliferated across various clinical departments with many invasive procedures now being performed under ultrasound guidance (Figure 1). Ultrasound guided procedures such as line placements and biopsies require the use of sterile gel and appropriately reprocessed ultrasound probes.

Nanosonics Limited

14 Mars Road

Lane Cove NSW 2066

Australia

www.nanosonics.com.au

Clinical Bulletin

Figure 1. Ultrasound is used to guide many invasive procedures.

Ultrasound guided procedure risk

Outbreaks from ultrasound gel

Infection transmission from ultrasound probes

Regulator alerts and recalls

As with many infection control issues, the presence of contaminated gel in these outbreaks has allowed infections to be traced and attributed to the ultrasound procedure. Causality can be established based on the same strain of organism being isolated from each patient and from the gel itself. Such situations provide a window into what is likely a broader problem. The role of ultrasound probes and gel in central line associated bloodstream infections (CLABSI) is likely underappreciated as it is difficult to link a particular infection to the ultrasound process versus

Figure 2. Biopsies are commonly performed under ultrasound guidance. The proximity of the probe and gel to the puncture site can lead to infection risk if precautions are not taken.

While these cases clearly demonstrate that contaminated gel can lead to infections, they also underscore the need to ensure that the ultrasound probe is appropriately reprocessed prior to use in these procedures.

other steps in the line placement procedure.

While ultrasound-guided invasive procedures represent significant risk, endocavitary ultrasound procedures have also been associated with serious infections. The Medicines and Healthcare Products Regulatory Agency (UK) issued an alert in 2012 for all healthcare facilities to review their decontamination policies and procedures related to reusable transoesophageal echocardiography, transvaginal and transrectal ultrasound probes. This was in immediate response

to a patient death from hepatitis B transmission from a procedure with an improperly reprocessed transoesophageal echocardiography probe.5 A further case of a patient contracting hepatitis C infection after undergoing transrectal prostate biopsy was reported in 2013. In this case the source of infection was suspected to be the use of improperly reprocessed ultrasound probes or needle guides that had biofilms deposited on them.6

have been several alerts issued in the past by regulatory agencies including the CDC, FDA and Health Canada on infection risk with contaminated ultrasound gels used in ultrasound guided interventional procedures. These are detailed along with other outbreaks in Appendix 1.

In September 2017, 2 patients died from septic shock following an outbreak traced to contaminated ultrasound gel used in central line placements.1 The source was confirmed by isolation of the same bacterium Burkholderia cepacia from patient blood cultures. The outbreak involved 14 patients in total and was published in the Journal of Hospital Infection. A few months prior, the Australian Therapeutic Goods Administration (TGA) received reports of an outbreak of Burkholderia cenocepacia in 11 patients who had undergone ultrasound guided central line placements or ultrasound-guided fluid drainages. Investigations similarly identified contaminated ultrasound gel as the source and the TGA recalled the gel product. 2,3 This investigation was published in the American Journal of Infection Control.

Several publications now demonstrate that the inadvertent use of contaminated ultrasound gel in ultrasound guided procedures can result in serious outbreaks. There

As the probe and gel may contact the sterile tissue of the puncture site the ultrasound probe is classified as a critical device and must undergo sterilization or high-level disinfection and be used with a sterile sheath (Figure 2).4

1. Abdelfattah R, Aljumaah S, Alqahtani A, Althawadi S, Barron I, Almofada S. Outbreak of Burkholderia cepacia bacteraemia

in a tertiary care centre due to contaminated ultrasound probe gel. Journal of Hospital Infection. 2017; pii:

S0195-6701(17)30516-9.

2. Shaban RZ, Maloney S, Gerrard J, Collignon P, et al. Outbreak of health care-associated Burkholderia cenocepacia

bacteremia and infection attributed to contaminated sterile gel used for central line insertion under ultrasound guidance

and other procedures. American Journal of Infection Control. 2017; 45(9):954-958

3. Therapeutic Goods Administration (TGA). Meditech Ultrasound Gel: Safety Advisory – Risk of Bacterial Contamination.

Safety Information – Alerts. 2017. Available from: https://www.tga.gov.au/alert/meditech-ultrasound-gel

4. Rutala WA, Weber DJ, Healthcare Infection Control Practices Advisory Committee (HICPAC), Centers for Disease Control

and Prevention (CDC). USA. Guideline for Disinfection and Sterilization in Healthcare Facilities. 2008 (Updated 15 February

2017). Available at: https://www.cdc.gov/infectioncontrol/pdf/guidelines/disinfection-guidelines.pdf

5. Medicines and Healthcare products Regulatory Agency UK. Medical Device Alert. 28 June 2012. Reusable

transoesophageal echocardiography, transvaginal and transrectal ultrasound probes (transducers). Document:

MDA/2012/037.

6. Ferhi K, Roupret M, Mozer P, Ploussard G, Haertig A, de La Taille A. Hepatitis C transmission after prostate biopsy.

Urology Case Reports. 2013;797248

7. Health Service Executive (HSE) Quality Improvement Division – Decontamination Safety Programme. Ireland, January

2017. HSE Guidance for Decontamination of Semi-critical Ultrasound Probes; Semi-invasive and Non-invasive

Ultrasound Probes. Document: QPSD-GL-028-1.

8. Health Facilities Scotland, NHS National Services Scotland, Health Protection Scotland. Scotland, March 2016. NHS

Scotland Guidance for Decontamination of Semi-Critical Ultrasound Probes; Semi-invasive and Non-invasive Ultrasound

Probes. Document: HPS/HFS Version 1.0.

9. Welsh Health Technical Memorandum WHTM 01-06. Wales, 2014. Decontamination of flexible endoscopes Part C:

Operational management (including guidance on non-channelled endoscopes and ultrasound probes).

10. Australasian College of Infection Prevention and Control and the Australasian Society for Ultrasound in Medicine.

Guidelines for Reprocessing Ultrasound Transducers. Australasian Journal of Ultrasound in Medicine. 2017;20(1):30-40.

11. Canada Standards Association (CSA Group). Canada 2014. CSA Z314.8-14 Decontamination of reusable medical

devices.

12. Canada Standards Association (CSA Group). Canada 2017. Draft Standard for Comments: CSA Z314, Canadian medical

device reprocessing. Edition 1.

MM0493-GLO-FY V03#

References

Given the widespread and broadening use of ultrasound, it is important to review standard procedures to ensure that they are consistent with the latest guidelines for use of ultrasound probes.

Guidelines in USA, Canada, UK and Australia all require a minimum of HLD or sterilization for endocavitary procedures contacting mucous membranes and ultrasound guided surface probe procedures where there is a risk of contact with sterile tissue. These requirements apply even if the probe is used with a sterile sheath.4,7-12

Author, Year Summary Procedure/ Probe Patient population Organism

No of cases

Alerts

TGA alert 2017

TGA (Australia) issued an alert on Meditech gel on 12 May 2017 following reports of 10 Australian patients being infected with Burkholderia cenocepacia. The bacterium was isolated from blood cultures of 9 of these patients who underwent ultrasound guided central line placements.

Ultrasound guided central line placement

Post-procedural ICU patients

Burkholderia cenocepacia

9

FDA alert 2012

FDA issued an alert on Other-Sonic Generic Ultrasound transmission gel in 2012 following reports of 16 patients being infected with Pseudomonas aeruginosa. All these patients had undergone transesophageal ultrasound using the gel which was contaminated with P. aeruginosa and Klebsiella oxytoca.

Transesophageal echocardio- gram ultrasound probes

Cardiovascular surgery patients

Pseudomonas aeruginosa

16

CDC alert 2012

CDC also issued an alert on the FDA recall of Other-Sonic Generic Ultrasound transmission gel in 2012 (see above).

Transesophageal echocardio- gram ultrasound probes

Cardiovascular surgery patients

Pseudomonas aeruginosa

16

MHRA alert 2012

MHRA (UK) issued a medical device alert regarding appropriate decontamination of all reusable transoesophageal echocardiography, transvaginal and transrectal ultrasound probes. This was in response to the death of a patient from hepatitis B infection that was associated with a failure to appropriately decontaminate a transoesophageal echocardiography probe between each patient use.

Transesophageal echocardio- gram ultrasound probes

Cardiology

hepatitis B

1

Health Canada alert 2004 General safety notice to Canadian hospitals on ultrasound and medical gels.

Publications

Abdelfattah et al, 2017

A detailed report of an outbreak of Burkholderia cepacia bacteremia in 14 ICU patients who underwent central line placements under ultrasound guidance, 2 of whom died due to bacteremia associated septic shock. The source of infection was identified to be contaminated ultrasound gels.

Ultrasound guided central line placement ICU patients

Burkholderia cepacia 14

Shaban et al, 2017

Detailed report on Burkholderia cenocepacia outbreak in 11 Australian patients due to contaminated ultrasound transmission gel used in ultrasound guided interventional procedures. The study emphasizes that not only gels but even contaminated ultrasound equipment can be sources of serious infections like septicaemia.

Ultrasound guided central line placement and fluid drainage

ICU patients

Burkholderia cenocepacia

11

Cheng et al, 2016

Study identified a total of 40 cases (28 adults and 12 children) of post-procedural Mycobacterium massiliense infections over a 3 year period where the invasive procedure involved use of ultrasound. The same strain of M. massiliense was isolated from the affected patients and ultrasound transmission gels, revealing ultrasound gel as the source of the outbreak. No new cases were identified after replacing the contaminated ultrasound gel.

Ultrasound guided procedures

Post-procedural patients

Mycobacte- rium massil- iense

38 patients in hospital A, 1 new- born and her mother in hospital B

Nannini et al, 2015

Study describes a nosocomial polyclonal outbreak of bacteremia caused by Burkholderia cepacia complex (BCC) in a total of 11 patients (7 neonates and 4 adults, 3 of whom had recent cardiovascular surgeries). The 7 neonates and 4 adults had undergone a mean of 5 and 2 ultrasounds (including transthoracic and transfontanellar) respectively. Culture studies of 80 environmental samples detected BCC strains from only ultrasound gel, including unopened bottles. Removal of the contaminated ultrasound gel stocks resulted in abrupt interruption of new cases.

Transthoracic and transfontanellar ultrasound

Preterm neo- nates, cardio- vascular surgery patients and general ward patient.

Burkholderia cepacia complex

11 – 7 neo- nates and 4 adults

Appendix 1: Alerts and publications on outbreaks from ultrasound procedures.

Author, Year Summary Procedure/ Probe Patient population Organism

No of cases

Oleszkowicz et al, 2012

Identified 16 patients with Pseudomonas aeruginosa bacteria in their respiratory tract post cardiovascular surgery where an intraoperative transesophageal echocardiogram (TEE) with ultrasound transmission gel as a conducting agent was used. Culture studies showed that multidose and unopened gel bottles had the same strain of P. aeruginosa as the outbreak strain isolated from 10 out 16 cases.

Transesophageal echocardiogram (TEE)

Cardiovascular surgery patients

Pseudomonas aeruginosa

16

Olshtain-Pops et al, 2011

Reported an outbreak of Achromobacter xylosoxidans in 4 patients post transrectal ultrasound guided prostate biopsy. Culture studies showed that contaminated ultrasound gel was the cause of the outbreak as the same isolates were obtained from patients and the gel.

Transrectal prostate biopsy (TRPB)

Urology patients

Achro- mobacter xylosoxidans

4

Organ et al, 2010

Reported 6 cases of Burkholderia cepacia prostatic infection after transrectal prostate biopsy using non-sterile ultrasound transmission gel. Culture studies showed that the strain of B. cepacia isolated from the contaminated bottles were the same as those isolated from the infected cases.

TRPB Patients with transrectal prostate biopsy

Burkholderia cepacia

6

Jacobson et al, 2006

Study showed that contaminated ultrasound gel contributed to the nosocomial infections due to Burkholderia cepacia complex in a total of 50 patients without cystic fibrosis in Canada over the course of 10 years. Of the 88 gel bottles tested, 42% were contaminated, 92% of which were contaminated with B. cepacia complex.

Urodynamic, Transthoracic echocardiogram (TTE), Doppler blood pressure (BP)

Pediatric patients

Burkholderia cepacia

Sustained endemicity

Hutchinson et al, 2004

Describes an outbreak of nosocomial Burkholderia cepacia infections in a total of 6 patients in Canada post transrectal biopsy. The ultrasound gel used in the procedure in these cases were found to be intrinsically contaminated with the same isolates of B. cepacea as those recovered from the blood of the 6 affected patients.

TRPB

Urology patients

Burkholderia cepacia

6

Weist et al, 2000

Describes an outbreak of methicillin susceptible Staphylococcus aureus (MSSA) pyodermas in 10 neonates after birth who underwent hip-joint sonographies using contaminated ultrasound gel. MSSA was isolated from the ultrasound gel and was identified as the source for MSSA infection.

Hip joint sonography

Neonatal patients

Staphylococ- cus aureus

10

Gaillot et al, 1998

Reports an outbreak of Klebsiella pneumonia colonization in 6 adult women and 2 neonates in France, resulting in 2 adult and 1 neonatal infection. The neonates were colonized by vertical transmission from the mother before or during the delivery. All of the 6 women had undergone a transvaginal ultrasound and K. pneumonia was recovered from the ultrasound coupling gel used in these procedures. Replacing the contaminated gel with single use gel broke the cycle of contamination.

Transvaginal ultrasound

OB/GYN, neona- tal patients

Klebsiella pneumoniae, ESBL producing

6 adults, 2 neonates

Keizur et al, 1993

This study describes urinary tract infection with Pseudomonas cepacia in possibly 9 patients post transrectal ultrasound guided needle biopsy of the prostrate. Environmental investigations revealed ultrasound transmission gel as the source of contamination.

Transvaginal ultrasound, abdominal ultrasound

Urology patients

Burkholderia cepacia

9 possible

Ferhi et al, 2013

This publication is a case report of a patient who contracted hepatitis C infection after undergoing prostate biopsy under ultrasound guidance. The forensic report of the case suspected biofilm contamination of the probe or needle guide as the source of the infection. The publication emphasizes proper adherence to infection control recommendations for these procedures.

TRPB

Healthy patient for individual prostate cancer screening

hepatitis C

1

Appendix 1 continued: Alerts and publications on outbreaks from ultrasound procedures.